The shrinkage is all the more perturbing because its dynamics are not well understood.
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As speech technology continues to improve, there will be new, compelling and possibly perturbing applications.
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Those ripples move outward from the source, perturbing the space-time around various objects, including Earth.
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More perturbing than the children who shriek at the bombardment around them are those who barely flinch.
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It's a type of (perhaps unconventional) white noise: light ambient hums that muffle perturbing or bothersome sounds.
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Their missives—cruel, tender, perturbing—are sketches of life in the provincial town where Tiller grew up.
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The Bank of England was, however, more specific about one of the problems perturbing policymakers around the world.
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It goes without saying that the termination of a particular experience carries with it the perturbing sting of mortality.
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If a black hole came by, or we came by it, we would notice its gravity perturbing planets and spacecraft.
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Equally perturbing is a confrontation documented in the exclusive clip below, which takes place outside the L.A. studio where they're filming.
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Yes. What's perhaps more perturbing for people is that these companies haven't been transparent about saying what they're doing and why.
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New research suggests Scholz's Star, as it's known, left traces of this interstellar encounter by perturbing some comets in the outer Oort Cloud.
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The gnarly winds rock the ice, perturbing the water beneath, and blow directly through cracks, hollows, and gaps in the sea ice, he explained.
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At the same time, from privileging matter and form alone, his sculptures are prickly with ideas, some in the form of perturbing conceptual ambushes.
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In a disturbed and perturbing time, one that calls out for some — any — form of revolt, the show hunkers down, cautions wait-and-see.
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Far more perturbing is the vague, elusive memory she has of once turning away from Aislinn's pleas, way back when Antoinette was still in uniform.
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It was perturbing to be discussing the relative merits of gassing New Yorkers with what was in effect Zyklon B or the equally nasty cyanogen chloride.
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Meanwhile, Assad's regime has used chemical weapons on its own people and planned to confiscate the property of those forced to flee, seemingly without perturbing Putin.
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This perturbing Japanese drama — the feature debut of Yui Kiyohara — had its North American premiere at the New Directors/New Films festival in New York last year.
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What might be more surprising — and even perturbing to other applicants — was that the winner, the poet Brian Sonia-Wallace, has also won a highly publicized Amtrak residency.
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Bringing together the processed voices of industrial machines, human voices, and animals—for a result that sounds alternately revving, piercing, and shattering—it's a slow burn, innervating yet viscerally perturbing.
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Sensors and cameras throughout it track people's positions and movements and relay them to the robots, and it's this, rather than my box-shaped companion, that I find more perturbing.
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He would also use our internal messaging channels to send me messages about his favorite animals having sex, asking me about my sex life and other perturbing and intrusive questions.
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Instead, I want to point out the incredible force of Ferrante's prose (beautifully translated by Ann Goldstein), which harbors so much perturbing nuance beneath a surface of such apparent directness.
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"Every high cloud doesn't indicate a new storm, of course, but what this does tell us is that something was perturbing the atmosphere before we could see a new storm," she said.
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To believe Meachem, Adams was not much more than a familiar, if perturbing, presence to Jefferson prior to the election of 210 — even though one was president and the other vice-president.
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Shade raises a perturbing question: Do you root for the planet-skipping alien who snatched a teenage girl's body or sympathize with the trauma-inducing bully who terrorized her friends and family?
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The effect, while not devoid of humor, is perturbing; the whispered chorus in "Vampiro" and the dissonant key change in "El Pozo" (the hook: "Uno dos tres/cuatro cinco seis") prickle the skin.
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Even if someone is doing something that you find perturbing, as long as nobody's getting hurt or encroaching on someone else's space, then your part is just to make sure the individual is okay.
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The restless career of one of the great provocateurs of early modernism finally gets its due from MoMA, healthfully perturbing that institution's emphasis on linear progress and creative genius with radically shifting styles and tones.
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His drawings of prepubescent and adolescent boys and girls, made concurrently with the emergence of Sigmund Freud's theories of psychosexual development, are clear-eyed if perturbing reflections of an artist being ruthlessly honest with himself.
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A referendum held before Britain leaves the EU would not be held on a clear strategy for future relations with the EU. What is most perturbing is the perils another referendum could impose upon our democracy.
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"It's perturbing to me to see that most of the renegotiation of labor agreements is done through strikes, and it doesn't have to be that way," said Arnaud Soirat, chief executive of Rio's Copper & Diamonds unit.
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It's difficult to calculate exactly where and when an asteroid will strike because these flying rocks interact with the solar wind and the distant gravitational pull of objects like Jupiter, steadily perturbing their orbits all the time.
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It's made even more perturbing in 2019, since his robot companion GERTY is voiced by Kevin Spacey, who is in the midst of legal proceedings around a slew of alleged assaults that came to light in 2017.
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The trailer raised another perturbing question: In a world where cats have human faces and loosely human physiques, where do actual humans, owners of the colossal beds and sofas and chandeliers the cats play on, fit in?
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Syeh expressed her displeasure to her 232,000 Instagram followers in a story that relayed her perturbing treatment in captions: "Yesterday at the Louvre, I was stopped at the entrance by a guard for my outfit," wrote Syeh.
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If only we had a model that could tell us the result of this experiment without having to do the experiment, because it's costly or complicated or even impossible [because it would involve perturbing a living human's gene].
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The restless career of one of the great provocateurs of early modernism finally gets its due from the Museum of Modern Art, healthfully perturbing that institution's emphasis on linear progress and creative genius with radically shifting styles and tones.
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We witness Abu Osama go into a fit of rage about infidels in the same breath as he tenderly coddles his younger son; the contrast between such outbursts against more domestic, almost heart-warming scenes yields a perturbing degree of emotional whiplash.
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Eventually, it will recurve out into the North Pacific, where some of its energy will interact with the jet stream (the river of fast-flowing air at high altitudes that helps steer weather systems), perturbing what has been a rather straight west-to-east airflow into a series of upper level waves or undulations.
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A theory called "spectrum broadcasting," for example, developed by Pawel Horodecki at the Gdańsk University of Technology in Poland and collaborators, attempts to generalize QD. Spectrum broadcast theory (which has only been worked through for a few idealized cases) identifies those states of an entangled quantum system and environment that provide objective information that many observers can obtain without perturbing it.
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Precise details about how drones pick up body temperature and the slightest change in the environment from 5,000 feet above are followed by the operator's perturbing account of an innocent family that walked away incredulously after being badly injured in the fury of a drone attack meant to target other suspects (who were immediately incinerated while planting a pipe in the ground).
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This was especially perturbing for Korolova, as she recounts on Medium, because she has studied the privacy harms that come from Facebook advertising, including how it could be previously used to gather data about an individual's likes, estimated income and interests (for which she and her co-author Irfan Faizullabhoy got a $2,000 bug bounty from Facebook), and how it can currently be used to target ads at a single house or building, if, say, an anti-choice group wanted to target women at a Planned Parenthood with an ad for baby clothes.
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Such extreme trans-Neptunian objects (ETNOs) can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine.
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These extreme trans-Neptunian objects (ETNOs) can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine.
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These extreme trans- Neptunian objects (ETNOs) can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine.
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It produces effects indicative of antidepressant, anxiolytic, antiobsessional, antiaggressive, and cognitive- and sleep-enhancing properties in animal models, all while not perturbing body weight or sexual behavior.
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The inferred orbital timescale is of the same order as the activity of the primary source, suggesting the secondary may be perturbing the primary and causing the outflows.
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Instead, kasugamycin mimics the codon nucleotides at the P and E sites by binding within the path of the mRNA, thus perturbing the mRNA-tRNA codon-anticodon interaction.
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The semimajor axis of any additional nontransiting outer gas giant must be larger than 30 AU to keep from perturbing the observed planetary system out of the transiting plane.
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The perturbing forces of the Sun on the Moon at two places in its orbit. The blue arrows represent the direction and magnitude of the gravitational force on the Earth. Applying this to both the Earth's and the Moon's position does not disturb the positions relative to each other. When it is subtracted from the force on the Moon (black arrows), what is left is the perturbing force (red arrows) on the Moon relative to the Earth.
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This also allows the use of electroporation for studying the effect of adding or silencing a gene. Other tools for perturbing their genetic makeup are chicken embryonic stem cells and viral vectors.
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While meiotic homologous pairing subsequently became well studied, somatic pairing remained neglected due to what has been described as "limitations in cytological tools for measuring pairing and genetic tools for perturbing pairing dynamics".
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Furthermore, a renderer using micropolygons can support displacement mapping simply by perturbing micropolygon vertices during shading. This displacement is usually not limited to the local surface normal but can be given an arbitrary direction.
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Perturbing forces cause orbits to become perturbed from a perfect Keplerian orbit. Models for each of these forces are created and executed during the orbit simulation so their effects on the orbit can be determined.
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Intracellular accumulation of betaines permits water retention in cells, thus protecting from the effects of dehydration. This accumulation is non-perturbing to enzyme function, protein structure, and membrane integrity. Betaine is also a methyl donor of increasingly recognised significance in biology.
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At this stage, it is difficult to measure nanoparticle properties in situ without perturbing the system. Post mortem or histological examination provides a way to measure these changes in the material, although the tissue itself can interfere with the measurements.
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Most orbit modeling approaches model the two-body problem and then add models of these perturbing forces and simulate these models over time. Perturbing forces may include gravitational attraction from other bodies besides the primary, solar wind, drag, magnetic fields, and propulsive forces. Analytical solutions (mathematical expressions to predict the positions and motions at any future time) for simple two-body and three-body problems exist; none have been found for the n-body problem except for certain special cases. Even the two-body problem becomes insoluble if one of the bodies is irregular in shape.
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The galaxy has a dark matter halo that has an estimated 3.5 times the mass of the gaseous and stellar components. There is a dwarf elliptical companion to the north of the galaxy, designated Arp 1981, that may be having a perturbing influence.
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To explain the abundance of binary and rapidly rotating TNOs, the rate of collisions among TNOs had likely increased as a result of Neptune's outward migration perturbing the orbits of TNOs, thus increasing the frequency of collisions which may have led to Varuna's rapid rotation.
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It is one a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more. Such objects can not reach such orbits without some perturbing object, which lead to the speculation of planet nine.
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The nuclear clock approach proposed by Campbell et al. slightly differs from the original one proposed by Peik and Tamm. Instead of exciting an electronic shell state in order to obtain the highest insensitivity against external perturbing fields, the nuclear clock proposed by Campbell et al.
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For decades physicists had been trying to incorporate the effect of microscopic quantum mechanical interactions between electrons in the theory of matter. Bohm and Pines' RPA accounts for the weak screened Coulomb interaction and is commonly used for describing the dynamic linear electronic response of electron systems. In the RPA, electrons are assumed to respond only to the total electric potential V(r) which is the sum of the external perturbing potential Vext(r) and a screening potential Vsc(r). The external perturbing potential is assumed to oscillate at a single frequency ω, so that the model yields via a self-consistent field (SCF) method a dynamic dielectric function denoted by εRPA(k, ω).
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In celestial mechanics, the expression tidal force can refer to a situation in which a body or material (for example, tidal water) is mainly under the gravitational influence of a second body (for example, the Earth), but is also perturbed by the gravitational effects of a third body (for example, the Moon). The perturbing force is sometimes in such cases called a tidal force"On the tidal force", I. N. Avsiuk, in "Soviet Astronomy Letters", vol. 3 (1977), pp. 96–99. (for example, the perturbing force on the Moon): it is the difference between the force exerted by the third body on the second and the force exerted by the third body on the first.
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Perturbing the Organism: The Biology of Stressful Experience. Chicago: University of Chicago Press, 1992. As members of a couple, they became external regulators for one another. They were attuned on many levels: their pupils dilated in synchrony, they echoed one another's speech patterns, movements, and even cardiac and EEG rhythms.
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It's coming from mainly George's angle again [the Boy is writing the music for the show] and that's slightly perturbing to me.' You talk about George like he has some real hold over you? 'I love George, we're friends and we've got a history together. The thing is, he's more famous than me.
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However, the length of any one synodic month can vary from 29.26 to 29.80 days due to the perturbing effects of the Sun's gravity on the Moon's eccentric orbit. In a lunar calendar, each month corresponds to one lunation. Each lunar cycle can be assigned a unique lunation number to identify it.
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It is one of a small group of extreme trans- Neptunian objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more. Such objects can not have reached their present-day orbits without the gravitational influence of some perturbing object, which lead to the speculation of planet nine.
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As mentioned above, the uplink and downlink carriers played a critical role in spacecraft tracking. Sidebands generated by the information also carried by the system had to be kept away from the carriers to avoid perturbing the phase locked loops used to track them. This was done through the use of various subcarriers. The uplink had two subcarriers.
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It must be noted that a variety of errors must be taken into consideration while perturbing the a priori, such as the error on the a priori, the instrumental error or the expected error. Alternatively, the IASI Level 1 data can be processed by least square fit algorithms. Again, the expected error must be taken into consideration.
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Beamforming is a signal processing technique used to spatially select propagating waves (most notably acoustic and electromagnetic waves). In order to implement beamforming on digital hardware the received signals need to be discretized. This introduces quantization error, perturbing the array pattern. For this reason, the sample rate must be generally much greater than the Nyquist rate.
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Because the perturbing force is different in direction and magnitude on opposite sides of the orbit, it produces a change in the shape of the orbit. In astronomy, perturbation is the complex motion of a massive body subject to forces other than the gravitational attraction of a single other massive body.Bate, Mueller, White (1971): ch. 9, p. 385.
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In 1821, Alexis Bouvard had published astronomical tables of the orbit of Uranus, making predictions of future positions based on Newton's laws of motion and gravitation.Bouvard, A. (1821) Tables astronomiques publiées par le Bureau des Longitudes de France, Paris, FR: Bachelier Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesise some perturbing body.[Anon.] (2001) "Bouvard, Alexis", Encyclopædia Britannica, Deluxe CDROM edition Adams learnt of the irregularities while still an undergraduate and became convinced of the "perturbation" theory. Adams believed, in the face of anything that had been attempted before, that he could use the observed data on Uranus, and utilising nothing more than Newton's law of gravitation, deduce the mass, position and orbit of the perturbing body. On 3 July 1841, he noted his intention to work on the problem.
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This myosin group has been found in the Apicomplexa phylum. The myosins localize to plasma membranes of the intracellular parasites and may then be involved in the cell invasion process. This myosin is also found in the ciliated protozoan Tetrahymena thermaphila. Known functions include: transporting phagosomes to the nucleus and perturbing the developmentally regulated elimination of the macronucleus during conjugation.
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The motions of the host star displayed Keplerian variation, indicating a perturbing body in orbit. The best fit model suggests a body having a minimum mass of and showing a 158-day orbital period with a semimajor axis of and a low eccentricity of 0.085. This is one of the two least massive planets known around clump giants, as of 2012.
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In 2008 Grinin et al. invoke the possible presence of a substellar object to explain peculiar and periodic eclipses occurring to the young star every 4.7 years. The presence of a planetary object is still invoked in a recent research. They infer a maximum mass of 6 times that of Jupiter for the perturbing object and an orbital separation of 3.3 astronomical units.
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The relative levels of the alternate forms may be regulated and involved in the normal control of planar cell polarity. Mutations in Prickle genes can cause epilepsy in humans by perturbing Prickle function. One mutation in Prickle1 gene can result in Prickle1-Related Progressive Myoclonus Epilepsy- Ataxia Syndrome. This mutation disrupts the interaction between prickle-like 1 and REST, which results in the inability to suppress REST.
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Another research trend is to try and alleviate premature convergence (that is, optimization stagnation), e.g. by reversing or perturbing the movement of the PSO particles, another approach to deal with premature convergence is the use of multiple swarms (multi-swarm optimization). The multi-swarm approach can also be used to implement multi-objective optimization. Finally, there are developments in adapting the behavioural parameters of PSO during optimization.
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Orbit models are typically propagated in time and space using special perturbation methods. This is performed by first modeling the orbit as a Keplerian orbit. Then perturbations are added to the model to account for the various perturbations that affect the orbit. Special perturbations can be applied to any problem in celestial mechanics, as it is not limited to cases where the perturbing forces are small.
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Tisserand's parameter (or Tisserand's invariant) is a value calculated from several orbital elements (semi-major axis, orbital eccentricity and inclination) of a relatively small object and a larger "perturbing body". It is used to distinguish different kinds of orbits. The term is named after French astronomer Félix Tisserand, and applies to restricted three-body problems in which the three objects all differ greatly in mass.
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This slice is a Poincaré section. After the information about the section has been gathered, one allows the system to run and waits until it comes near a desired periodic orbit in the section. Next, the system is encouraged to remain on that orbit by perturbing the appropriate parameter. When the control parameter is actually changed, the chaotic attractor is shifted and distorted somewhat.
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Orbital period variations suggest the presence of one more perturbing unseen object around the eclipsing binary. Several publications have tried to set constrains to putative orbital period and minimum mass for unseen component. The most recent article proposes an orbital period of 29.8 years for a stellar object with roughly three fourths the Sun's mass and high orbital eccentricity (e=0.66). Inclination is assumed being 33.6 degrees.
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It was discovered by the Cassini Imaging Team in images taken on 30 May 2007. Once the discovery was made, a search of older Cassini images revealed it in observations from as far back as June 2004. It was first announced on 18 July 2007. Discovery images of Anthe Anthe is visibly affected by a perturbing 10:11 mean-longitude resonance with the much larger Mimas.
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Albert Libchaber made major contributions in experimental condensed matter physics.Mukerjee, M. (1996) Profile: Albert Libchaber - Seeing the World in a Snowflake, Scientific American 274(3), 36-42. In particular, he carried out the first experimental observation of the bifurcation cascade that leads to chaos and turbulence in convective Rayleigh–Bénard systems. Using microbolometers engraved in the convective cell he was able to observe temperature fluctuations without perturbing the environment.
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Methone's orbit is visibly affected by a perturbing 14:15 mean-longitude resonance with the much larger Mimas. This causes its osculating orbital elements to vary with an amplitude of about in semi-major axis, and 5° in longitude of its periapsis on a timescale of about 450 days. Its eccentricity also varies on different timescales between 0.0011 and 0.0037, and its inclination between about 0.003° and 0.020°.
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The results demonstrated that ADEP is perturbing bacterial cell division. To identify the reason why ADEP inhibited cell division, researchers monitored septum formation and nucleoid segregation in ADEP B. subtilis and ADEP S. aureus. The S. aureus and B. subtilis samples gave equivalent results. This part showed the importance of wild type of ClpP and inhibition of septum formation is by direct interference of ADEP with the cell division components.
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A significant quantity of fibrils resulting from primary nucleation and fibril elongation may be formed during the lag phase and secondary steps, rather than only fibril elongation, can be the dominant processes contributing to fibril growth during the exponential phase. With this new model, any perturbing agents of amyloid fibril formation, such as putative drugs, metabolites, mutations, chaperones, etc., can be assigned to a specific step of fibril formation.
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Le Verrier sent his position to Johann Gottfried Galle, asking him to verify. The same night, Galle spotted Neptune near the position Le Verrier had predicted. By the end of the 19th century, Le Verrier showed that the orbit of Mercury could not be accounted for entirely under Newtonian gravity, and all searches for another perturbing body (such as a planet orbiting the Sun even closer than Mercury) were fruitless.
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A promising approach to studying these structures is near field scanning optical microscopy (NSOM). Like AFM, NSOM relies on the scanning of a micromachined tip to give a highly localized signal. But unlike AFM, NSOM uses an optical rather than physical interaction with the sample, potentially perturbing delicate structures to a lesser extent. Fluorescence micrograph of a supported bilayer on a substrate that has been patterned with a corral.
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As attention on interoception increases among the scientific community, new research methods and treatment tactics are beginning to emerge. Ongoing research in interoception has shown the importance of perturbing interoceptive systems. This allows researchers the ability to document the effects of non-baseline states, which occur during times of panic or anxiety. It also provides the participant the ability to gauge the intensity of sensations within the body.
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In their paper of 2003, Grinin et al. invoke the possible presence of a substellar object to explain peculiar and periodic eclipses occurring to the young star every 8.3 days. They infer a mass of 20 times that of Jupiter for the perturbing object and an orbital separation of 0.08 Astronomical Units. Later studies find no evidence for a planet, instead finding multiple rings with accretion streams between them.
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IX Special perturbations can be applied to any problem in celestial mechanics, as it is not limited to cases where the perturbing forces are small. Once applied only to comets and minor planets, special perturbation methods are now the basis of the most accurate machine-generated planetary ephemerides of the great astronomical almanacs.See, for instance, Jet Propulsion Laboratory Development Ephemeris. Special perturbations are also used for modeling an orbit with computers.
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A PageRank-based algorithm could identify important protein targets in the pathogen organism better than a method considering only the number of incoming edges (in-degree) of a node in the metabolic network. The reason for this is that some already known, important protein targets do not have a high degree (are not hubs) and also, perturbing some hubs could result in unwanted physiological effects.Russell RB, Aloy P (2008). "Targeting and tinkering with interaction networks".
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The overall gain spectrum can be derived analytically, as is shown below. Random perturbations will generally contain a broad range of frequency components, and so will cause the generation of spectral sidebands which reflect the underlying gain spectrum. The tendency of a perturbing signal to grow makes modulation instability a form of amplification. By tuning an input signal to a peak of the gain spectrum, it is possible to create an optical amplifier.
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LHS 6343 may have a massive planet within the system. In 2012, transit-timing variation was analyzed for any possible substellar companions that may be perturbing the brown dwarf from its normal orbit. Such an object would be less massive than Jupiter and its orbital period would be 3.5 to 8 times larger than that of the brown dwarf. However, the hypothetical perturber's existence has not been confirmed and warrants more observations of the system.
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Hence, most experiments on the ionosphere give only small pieces of information. HAARP approaches the study of the ionosphere by following in the footsteps of an ionospheric heater called EISCAT near Tromsø, Norway. There, scientists pioneered exploration of the ionosphere by perturbing it with radio waves in the 2–10 MHz range, and studying how the ionosphere reacts. HAARP performs the same functions but with more power and a more flexible and agile HF beam.
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Consequently, we rely on the stronger definition above which implies that the irrationals are typical and the rationals are not. For applications, if a property holds on a residual set, it may not hold for every point, but perturbing it slightly will generally land one inside the residual set (by nowhere density of the components of the meagre set), and these are thus the most important case to address in theorems and algorithms.
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Pallene is visibly affected by a perturbing mean-longitude resonance with the much larger Enceladus, although this effect is not as large as Mimas's perturbations on Methone. The perturbations cause Pallene's osculating orbital elements to vary with an amplitude of about 4 km in semi-major axis, and 0.02° in longitude (corresponding to about 75 km). Eccentricity also changes on various timescales between 0.002 and 0.006, and inclination between about 0.178° and 0.184°.
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He could not observe Uranus from Pulkovo because it was too far south. In 1888, Struve discovered libration of Hyperion (the seventh moon of Saturn) and explained it by the perturbing action of the largest Saturn's moon, Titan. The same year, he introduced an intersatelite method of correcting orbital position of satellites. The method was rather successful because systematic errors in visual observations of some planets, such as Mars, were unacceptably large.
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Radial velocity variations of Theta Cygni have been detected by the ELODIE team while searching of extrasolar planets. Desort et al. (2009) infer these variations are not caused by a dim stellar companion roughly 80 Astronomical Units away from the star, but suggest instead the presence of a perturbing planetary object, twice as massive as Jupiter and orbiting around the primary star in roughly 150 days. This extrasolar planet has yet to be confirmed.
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Return, Reclamation, Rehabilitation banned voter registration for incoming elections from taking place in Koui and Ngaoundaye.Central African Republic: 3R Rebels In Accused Of Perturbing Electoral Registration On 6 August 2020 UPC banned voter registration from taking in place in Bambouti in Haut-Mbomou demanding ransom. As of 15 October only 700 people were able to register to vote in Haut-Mbomou prefecture as a result of UPC and LRA presence in region.
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With the release of Gaia DR2, the presence of any stellar companions was ruled out.The recorded excess noise for the stars is 0.398 ± 0.008 mas, which corresponds to an angular size of 0.0106 ± 0.0002 AU at the stars' distance. This rules out any bodies capable of perturbing the stars by more than 0.0106 AU from their current velocities over the 2-year observation period. The stars, for comparison, orbit each other 0.0083 AU apart.
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Orbital period variations suggest the presence of one more perturbing unseen object. The authors He & Qian have estimated two possible orbital periods and minimum masses for unseen companions: the former cyclic oscillation would occur every 51.22 years (with amplitude of 0.0218 days) being caused by a low-mass stellar companion (likely a M dwarf star), whereas the latter would consist in a 32.1 years period and the unseen object could likely be substellar.
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After his retirement, Wulf did research with Seth Nicholson, working with the solar telescope and other equipment at the Mount Wilson observatory. Wulf and Nicholson published several articles based upon their study of the relation between solar activity, geomagnetic activity, and Earth’s magnetic field. They also studied the Moon's effects in perturbing recurrent geomagnetic activity induced by the Sun. In one project Wulf and Nicholson studied global atmospheric tides induced by the Moon and the Sun.
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This perturbing object, designated HD 167665 b, has an orbital period of twelve years with an eccentricity of 0.337. The semimajor axis of this orbit is more than 5.47 AU and the object has a mass of at least . Since the inclination of the orbit is unknown, the exact mass can not yet be determined. However, there is a 79% chance that the mass of the object constrains it to be a brown dwarf with a mass less than .
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This coupling introduces additional energy states and, in turn, multi- lined spectra. In such cases, the spacing between the EPR spectral lines indicates the degree of interaction between the unpaired electron and the perturbing nuclei. The hyperfine coupling constant of a nucleus is directly related to the spectral line spacing and, in the simplest cases, is essentially the spacing itself. Two common mechanisms by which electrons and nuclei interact are the Fermi contact interaction and by dipolar interaction.
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The precession of the equinox The equinox moves, in the sense that as time progresses it is in a different location with respect to the distant stars. Consequently, star catalogs over the years, even over the course of a few decades, will list different ephemerides. This is due to precession and nutation, both of which can be modeled, as well as other minor perturbing forces which can only be determined by observation and are thus tabulated in astronomical almanacs.
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The star is drifting closer with a radial velocity of −77 km/s, and is predicted to come to within in 334,000 years. At that distance the star can have a relatively small perturbing effect on comets in the Oort cloud. This is an ordinary G-type main-sequence star with a stellar classification of G0V, indicating that it is generating energy through core hydrogen fusion. It is roughly 8 billion years old and appears metal- deficient.
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HAT-P-1b is located in a very close orbit to its star, taking only 4.47 days to complete. It therefore falls into the category of hot Jupiters. At only 8.27 million kilometers from the star, tidal forces would circularise the orbit unless another perturbing body exists in the system. At the present time, the existing measurements are not sufficient to determine the orbital eccentricity, so a perfectly circular orbit has been assumed by the discoverers.
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Molecular dynamics simulations allow scientists to study the time evolution of a chemical system in discrete time intervals. These simulations often utilize molecular mechanics force fields which are generally empirical, parametrized functions which can efficiently calculate the properties and motions of large system., Parametrization is often to a higher level theory or experimental data. MC simulations allow one to explore the potential energy surface of a system by perturbing the system and calculating the energy after the perturbation.
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On September 17, 2002, this star was found to have a planetary companion, designated Rho Indi b. The discovery was made by measuring variations in the host star's radial velocity, thereby indicating the presence of a perturbing object. Based upon the data, the object is orbiting the host star with a period of about 3.7 years at an eccentricity of 0.32. The semimajor axis for this orbit is around 2.5 times the distance from the Earth to the Sun.
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The Meyer-Overton rule predicts the constant increase of anaesthetic potency of n-alkanols with increasing chain length. However, above certain length the potency vanishes. If general anaesthetics disrupt ion channels by partitioning into and perturbing the lipid bilayer, then one would expect that their solubility in lipid bilayers would also display the cutoff effect. However, partitioning of alcohols into lipid bilayers does not display a cutoff for long-chain alcohols from n-decanol to n-pentadecanol.
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Gargi Vachaknavi is one of the earliest known woman sage from the Vedic period. Gargi composed several hymns that questioned the origin of all existence.Gargi - The Virgin Philosopher Swami Sivananda She is mentioned in the Sixth and the Eighth Brahmana of Brihadaranyaka Upanishad, where the brahmayajna, a philosophic congress organized by King Janaka of Videha is described, she challenged the sage Yajnavalkya with perturbing questions on the atman (soul). Bhairavi Brahmani is a guru of Sri Ramakrishna.
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Equilibrium system states are much easier to describe in a deterministic manner than non- equilibrium states. For a process to be reversible, each step in the process must be reversible. For a step in a process to be reversible, the system must be in equilibrium throughout the step. That ideal cannot be accomplished in practice because no step can be taken without perturbing the system from equilibrium, but the ideal can be approached by making changes slowly.
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In methods of general perturbations, general differential equations, either of motion or of change in the orbital elements, are solved analytically, usually by series expansions. The result is usually expressed in terms of algebraic and trigonometric functions of the orbital elements of the body in question and the perturbing bodies. This can be applied generally to many different sets of conditions, and is not specific to any particular set of gravitating objects.Bate, Mueller, White (1971): p.
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Further afield, some tropical records report a cooling, based on cores drilled into an ancient coral reef in Indonesia. The event also caused a global CO2 decline of about 25 ppm over about 300 years. However, dating and interpretation of other tropical sites are more ambiguous than the North Atlantic sites. In addition, climate modeling work shows that the amount of meltwater and the pathway of meltwater are both important in perturbing the North Atlantic thermohaline circulation.
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On May 17, 2005, this asteroid occulted a faint star (magnitude 8.5) and the event was observed and timed in a number of locations within the U.S. and Mexico. As a result, a silhouette profile was produced, yielding a roughly oval cross- section with dimensions of 160 × 135 km (± 1 km).D.W. Dunham, "Upcoming Asteroid Occultations", Sky & Telescope, June, 2006, p. 63. The mass of the asteroid can be estimated based upon the mutually perturbing effects of other bodies, yielding an estimate of .
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Perturbing, harming or killing any life form, including any human being, is considered a sin in Jainism, with negative karmic effects. Souls begin their journey in a primordial state, and exist in a state of consciousness continuum that is constantly evolving through Saṃsāra. Some evolve to a higher state; some regress asserts the Jain theory, a movement that is driven by the karma. Further, Jain traditions believe that there exist Abhavya (incapable), or a class of souls that can never attain moksha (liberation).
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As the soul cycles, states Padmanabh Jaini, Jainism traditions believe that it goes through five types of bodies: earth bodies, water bodies, fire bodies, air bodies and vegetable lives. With all human and non-human activities, such as rainfall, agriculture, eating and even breathing, minuscule living beings are taking birth or dying, their souls are believed to be constantly changing bodies. Perturbing, harming or killing any life form, including any human being, is considered a sin in Jainism, with negative karmic effects.
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Aqueous solutions of manganese(II) chloride are used in 31P-NMR to determine the size and lamellarity of phospholipid vesicles. When manganese chloride is added to a vesicular solution, Mn2+ paramagnetic ions are released, perturbing the relaxation time of the phospholipids' phosphate groups and broadening the resulting 31P resonance signal. Only phospholipids located in the outermost monolayer exposed to Mn2+ experience this broadening. The effect is negligible for multilamellar vesicles, but for large unilamellar vesicles, a ~50% reduction in signal intensity is observed.
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Schematic of bump-and-hole method. The bump-and-hole method is a tool in chemical genetics for studying a specific isoform in a protein family without perturbing the other members of the family. The unattainability of isoform- selective inhibition due to structural homology in protein families is a major challenge of chemical genetics. With the bump-and-hole approach, a protein–ligand interface is engineered to achieve selectivity through steric complementarity while maintaining biochemical competence and orthogonality to the wild type pair.
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The protein crowding mechanism hypothesizes that proteins can bend membrane without directly perturbing membrane structures like the above mechanisms. When a high enough local concentration of protein is present on membrane surface, repulsion between protein molecules on the membrane surface can induce membrane curvature. Although contribution of this mechanism remains unclear, multiple experimental and computation evidences have shown its potential in bending membrane. A recent study even shows that protein crowding can cause membrane bending and leads to membrane fission.
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Safranal is an effective anticonvulsant in animal models, shown to act as an agonist at GABAA receptors. Safranal also exhibits high antioxidant and free radical scavenging activity, along with cytotoxicity towards cancer cells in vitro.. One of its anticancer mechanisms of action involves disruption of the normal assembly dynamics of cellular microtubules Cheriyamundath S, Choudhary S, and Lopus M (2017) Safranal inhibits HeLa cell viability by perturbing the reassembly potential of microtubules. Phytother Res, 32, 170-173. doi: 10.1002/ptr.5938.
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An article by Gomes, Soares, and Brasser was published in 2015, detailing their arguments. In 2014, astronomers Chad Trujillo and Scott S. Sheppard noted the similarities in the orbits of Sedna and and several other eTNOs. They proposed that an unknown planet in a circular orbit between 200 and 300 AU was perturbing their orbits. Later, in 2015, Raúl and Carlos de la Fuente Marco argued that two massive planets in orbital resonance were necessary to produce the similarities of so many orbits.
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The apparent motion of the Sun along the ecliptic (red) as seen on the inside of the celestial sphere. Ecliptic coordinates appear in (red). The celestial equator (blue) and the equatorial coordinates (blue), being inclined to the ecliptic, appear to wobble as the Sun advances. The celestial equator and the ecliptic are slowly moving due to perturbing forces on the Earth, therefore the orientation of the primary direction, their intersection at the Northern Hemisphere vernal equinox, is not quite fixed.
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This class of graphs was first suggested by Michael Fellows in 1988, motivated by the fact that it is closed under edge contraction and induced subgraph operations.. A polygon-circle graph can be represented as an "alternating sequence". Such a sequence can be gained by perturbing the polygons representing the graph (if necessary) so that no two share a vertex, and then listing for each vertex (in circular order, starting at an arbitrary point) the polygon attached to that vertex.
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In the Solar System, this is usually the case; Jupiter, the second largest body, has a mass of about 1/1000 that of the Sun. General perturbation methods are preferred for some types of problems, as the source of certain observed motions are readily found. This is not necessarily so for special perturbations; the motions would be predicted with similar accuracy, but no information on the configurations of the perturbing bodies (for instance, an orbital resonance) which caused them would be available.
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In celestial mechanics, the eccentricity vector of a Kepler orbit is the dimensionless vector with direction pointing from apoapsis to periapsis and with magnitude equal to the orbit's scalar eccentricity. For Kepler orbits the eccentricity vector is a constant of motion. Its main use is in the analysis of almost circular orbits, as perturbing (non-Keplerian) forces on an actual orbit will cause the osculating eccentricity vector to change continuously. For the eccentricity and argument of periapsis parameters, eccentricity zero (circular orbit) corresponds to a singularity.
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He then adjusted the characteristics of the perturbing body in a way suggested by the residuals and repeated the process, a process similar to regression analysis. On 13 February 1844, James Challis, director of the Cambridge Observatory, requested data on the position of Uranus, for Adams, from Astronomer Royal George Biddell Airy at the Royal Observatory, Greenwich. Adams certainly completed some calculations on 18 September 1845. Supposedly, Adams communicated his work to Challis in mid-September 1845 but there is some controversy as to how.
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A number of algorithms are therefore used to search among the possible trees. Many of these involve taking an initial tree (usually the favored tree from the last iteration of the algorithm), and perturbing it to see if the change produces a higher score. The trees resulting from parsimony search are unrooted: They show all the possible relationships of the included taxa, but they lack any statement on relative times of divergence. A particular branch is chosen to root the tree by the user.
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For most spacecraft, changes to orbits are caused by the oblateness of the Earth, gravitational attraction from the sun and moon, solar radiation pressure, and air drag. These are called "perturbing forces". They must be counteracted by maneuvers to keep the spacecraft in the desired orbit. For a geostationary spacecraft, correction maneuvers on the order of 40–50 m/s per year are required to counteract the gravitational forces from the sun and moon which move the orbital plane away from the equatorial plane of the Earth.
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Alternatively, if the sun lies in the orbital plane, the vehicle will always pass over places where it is midday on the north-bound leg, and places where it is midnight on the south-bound leg (or vice versa). These are called "Noon-Midnight" orbits. Such orbits are desirable for many Earth observation missions such as weather, imagery, and mapping. The perturbing force caused by the oblateness of the Earth will in general perturb not only the orbital plane but also the eccentricity vector of the orbit.
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Examples are the Sun, Earth and a spacecraft, or Saturn, Titan and the Cassini spacecraft (using the semi-major axis of the perturbing body instead of a_J). This imposes a constraint on how a gravity assist may be used to alter a spacecraft's orbit. The Tisserand parameter will change if the spacecraft makes a propulsive maneuver or a gravity assist of some fourth object, which is one reason that many spacecraft frequently combine Earth and Venus (or Mars) gravity assists or also perform large deep space maneuvers.
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A machine-tweaked image of a dog was shown to look like a cat to both computers and humans. A 2019 study reported that humans can guess how machines will classify adversarial images. Researchers discovered methods for perturbing the appearance of a stop sign such that an autonomous vehicle classified it as a merge or speed limit sign. McAfee attacked Tesla's former Mobileye system, fooling it into driving 50 mph over the speed limit, simply by adding a two-inch strip of black tape to a speed limit sign.
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This means that when Pluto is closest to the Sun, it is at its farthest above the plane of the Solar System, preventing encounters with Neptune. This is a consequence of the Kozai mechanism, which relates the eccentricity of an orbit to its inclination to a larger perturbing body—in this case Neptune. Relative to Neptune, the amplitude of libration is 38°, and so the angular separation of Pluto's perihelion to the orbit of Neptune is always greater than 52° . The closest such angular separation occurs every 10,000 years.
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', also known as , is a trans-Neptunian object from the outermost region of the Solar System, approximately in diameter. It was first observed on 24 May 2015, by astronomers of the Outer Solar System Origins Survey using the Canada–France–Hawaii Telescope at Mauna Kea Observatories, Hawaii, United States. It is one a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 250 AU or more. Such objects can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine.
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Pierre-Simon Laplace had given an explanation in 1787 in terms of changes in the eccentricity of the Earth's orbit. He considered only the radial gravitational force on the Moon from the Sun and Earth but obtained close agreement with the historical record of observations. In 1820, at the insistence of the Académie des sciences, Damoiseau, Plana and Francesco Carlini revisited Laplace's work, investigating quadratic and higher-order perturbing terms, and obtained similar results, again addressing only a radial, and neglecting tangential, gravitational force on the Moon. Hansen obtained similar results in 1842 and 1847.
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Molecular imaging emerged in the mid twentieth century as a discipline at the intersection of molecular biology and in vivo imaging. It enables the visualisation of the cellular function and the follow-up of the molecular process in living organisms without perturbing them. The multiple and numerous potentialities of this field are applicable to the diagnosis of diseases such as cancer, and neurological and cardiovascular diseases. This technique also contributes to improving the treatment of these disorders by optimizing the pre-clinical and clinical tests of new medication.
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This could also explain why an object responsible for perturbing the orbits of the eTNOs, if it exists, has yet to be seen. A detection method was proposed in the paper, stating that the black hole is too cold to be detected over the CMB, but interaction with surrounding dark matter would produce gamma rays detectable by the FERMILAT. Konstantin Batygin commented on this, saying while it is possible for Planet Nine to be a primordial black hole, there is currently not enough evidence to make this idea more plausible than any other alternative.
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' has a similar size and orbit as . ' belongs to a small group of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more. These extreme trans-Neptunian objects (ETNOs) can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine. It is also denoted at extended detached disc object or extreme distant detached object (EDDO). It orbits the Sun at a distance of 45.6–788 AU once every 8512 years (3,109,107 days; semi-major axis of 417 AU).
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' is a member of the centaurs, a population of inward-moving bodies transiting from the Kuiper belt to the group of Jupiter-family comets. Orbiting mainly between Jupiter and Neptune, they typically have a semi-major axis of 5.5 to 30.1 AU. Centaurs are cometary-like bodies with an eccentric orbit. Their short dynamical lifetime is due to the perturbing forces exerted on them by the outer planets of the Solar System. The object is on a retrograde orbit as it has an inclination of more than 90°.
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' is a member of the centaurs, a population of inward-moving bodies transiting from the Kuiper belt to the group of Jupiter-family comets. Orbiting mainly between Jupiter and Neptune, they typically have a semi-major axis of 5.5 to 30.1 AU. Centaurs are cometary-like bodies with an eccentric orbit. Their short dynamical lifetime is due to the perturbing forces exerted on them by the outer planets of the Solar System. The object is on a retrograde orbit as it has an inclination of more than 90°.
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The laser wavelength is known to ±0.025 ppb and the clock is stable to ±0.03 ppb as well. Great care must be taken to minimize the effects of perturbing forces such as residual air resistance (even in vacuum), vibration, and magnetic forces. Such instruments are capable of an accuracy of about two parts per billion or 0.002 mGal and reference their measurement to atomic standards of length and time. Their primary use is for calibrating relative instruments, monitoring crustal deformation, and in geophysical studies requiring high accuracy and stability.
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A sheet of aufeis in a glacial valley in Mongolia Aufeis accumulates during winter along stream and river valleys in arctic and subarctic environments. It forms by upwelling of river water behind ice dams, or by ground-water discharge. The latter mechanism prevails in high-gradient alpine streams as they freeze solid. Ground-water discharge is blocked by ice, perturbing the steady-state condition and causing a small incremental rise in the local water table until discharge occurs along the bank and over the top of the previously formed ice.
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In chemical biology, bioorthogonal chemical reporter is a non-native chemical functionality that is introduced into the naturally occurring biomolecules of a living system, generally through metabolic or protein engineering. These functional groups are subsequently utilized for tagging and visualizing biomolecules. Jennifer Prescher & Carolyn R. Bertozzi, the developers of bioorthogonal chemistry, defined bioorthogonal chemical reporters as "non- native, non-perturbing chemical handles that can be modified in living systems through highly selective reactions with exogenously delivered probes." It has been used to enrich proteins and to conduct proteomic analysis.
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' belongs to a small group of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more. Such extreme trans-Neptunian objects (ETNOs) can not reach such orbits without some perturbing object, which lead to the speculation of Planet Nine. It orbits the Sun at a distance of 39–270 AU once every 1923 years and 10 months (702,689 days; semi-major axis of 154.68 AU). Its orbit has an eccentricity of 0.75 and an inclination of 20° with respect to the ecliptic.
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A propagation diagram for a standard solar model showing where oscillations have a g-mode character (blue) or where dipole modes have a p-mode character (orange). Between about 100 and 400 µHz, modes would potentially have two oscillating regions: these are known as mixed modes. The dashed line shows the acoustic cut-off frequency, computed from more precise modelling, and above which modes are not trapped in the star, and roughly-speaking do not resonate. By linearly perturbing the equations defining the mechanical equilibrium of a star (i.e.
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Spiral arms also have the ability to cause climatic changes on a planet. Passing through the dense molecular clouds of galactic spiral arms, stellar winds may be pushed back to the point that a reflective hydrogen layer accumulates in an orbiting planet's atmosphere, perhaps leading to a snowball Earth scenario. A galactic bar also has the potential to affect the size of the galactic habitable zone. Galactic bars are thought to grow over time, eventually reaching the corotation radius of the galaxy and perturbing the orbits of the stars located there.
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The salt bridge most often arises from the anionic carboxylate (RCOO−) of either aspartic acid or glutamic acid and the cationic ammonium (RNH3+) from lysine or the guanidinium (RNHC(NH2)2+) of arginine (Figure 2). Although these are the most common, other residues with ionizable side chains such as histidine, tyrosine, and serine can also participate, depending on outside factors perturbing their pKa's. The distance between the residues participating in the salt bridge is also cited as being important. The distance required is less than 4 Å (400 pm).
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Oursler's early installation works are immersive dark-room environments with video, sound, and language mixed with colorful constructed sculptural elements. In these projects, Oursler experimented with methods of removing the moving image from the video monitor using reflections in water, mirrors, glass and other devices. The early installation Son of Oil, presented at MoMA PS1 in 1982, links the dystopian feelings brought about by conspiracy theories with the perturbing politics of the oil industry. The large-scale installation L7-L5 deals with science fiction as entertainment in contradiction to the terror of first-hand accounts of alien encounters.
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Pressure and shock waves released by electric discharges are capable of perturbing the air in their vicinity up to 80%. This, however, has immediate consequences on the motion and properties of secondary streamer discharges in perturbed air: Depending on the direction (relative to the ambient electric field), air perturbations change the discharge velocities, facilitate branching or trigger the spontaneous initiation of a counter discharge. Recent simulations have shown that such perturbations are even capable to facilitate the production of X-rays (with energies of several tens of keV) from such streamer discharges, which are produced by run-away electrons through the Bremsstrahlung process.
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Its disk of stars can be traced out to a radius of around . This disk begins to warp at a radius of around , suggesting the perturbing effect of in-falling matter from the surrounding medium. The rotational behavior of the galaxy suggests there is a massive nuclear bulge, with a low-ionization nuclear emission-line region (LINER) at the core; a type of region that is characterized by spectral line emission from weakly ionized atoms. A prominent molecular ring is orbiting at a radius of , which is providing a star-forming region of gas and dust.
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Electrospray ionization mass spectrometry is a very versatile technique, consisting in a transfer of the formed complexes from the injected solution to the gas phase by a soft ionization process without strongly perturbing the complex stability. In addition, a small amount of the prepared solution needs to be injected to obtain the speciation spectra. Speciation of several metal ions can be investigated in monophasic solutions at increasing ligand concentration in order to explore all potential complexes. Collision Induced Dissociation (CID) analysis can be also performed to assess the kinetic stability of the formed complexes by discovering the main fragmentation pathway of the ligand.
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Haret’s major scientific contribution was made in 1878, in his Ph.D. thesis Sur l’invariabilité des grandes axes des orbites planétaires. At the time it was known that planets disturb each other’s orbits, thus deviating from the elliptic motion described by Johannes Kepler’s First Law. Pierre Laplace (in 1773) and Joseph Louis Lagrange (in 1776) had already studied the problem, both of them showing that the major axes of the orbits are stable, by using a first degree approximation of the perturbing forces. In 1808 Siméon Denis Poisson had proved that the stability also holds when using second degree approximations.
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Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesise that an unknown body was perturbing the orbit through gravitational interaction. In 1843, John Couch Adams began work on the orbit of Uranus using the data he had. He requested extra data from Sir George Airy, the Astronomer Royal, who supplied it in February 1844. Adams continued to work in 1845–46 and produced several different estimates of a new planet. Urbain Le Verrier In 1845–46, Urbain Le Verrier, independently of Adams, developed his own calculations but aroused no enthusiasm in his compatriots.
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Although a periodicity of 73.26 days has been observed in the star's radial velocity, it seems likely to be bound more to stellar activity than to a planetary object in close orbit. No substellar companion has been detected so far around Pi³ Orionis and the McDonald Observatory team has set limits to the presence of one or more planets with masses between 0.84 and 46.7 Jupiter masses and average separations spanning between 0.05 and 5.2 astronomical units. Thus, so far it appears that planets could easily orbit in the habitable zone without any complications caused by a gravitationally perturbing body.
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Leon Glass and Michael Mackey (1988) developed the theory behind limit cycle oscillators to observe the effects of perturbing oscillating neurons under the assumption the stimulus applied only affected the phase cycle and not the amplitude of response. Phase resetting plays a role in promoting neural synchrony in various pathways in the brain, from regulating circadian rhythms and heartbeat via cardiac pacemaker cells to playing significant roles in memory, pancreatic cells and neurodegenerative diseases such as epilepsy. Burst of activity in patterns of behaviors occur through coupled oscillators using pulsatile signals, better known as pulse-coupled oscillators.
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The reverse is true at b, where the perturbation retards the orbital motion of Uranus. John Couch Adams learned of the irregularities while still an undergraduate and became convinced of the "perturbation" hypothesis. Adams believed, in the face of anything that had been attempted before, that he could use the observed data on Uranus, and utilising nothing more than Newton's law of gravitation, deduce the mass, position and orbit of the perturbing body. After his final examinations in 1843, Adams was elected fellow of his college and spent the summer vacation in Cornwall calculating the first of six iterations.
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John Couch Adams In modern terms, the problem is an inverse problem, an attempt to deduce the parameters of a mathematical model from observed data. Though the problem is a simple one for modern mathematics after the advent of electronic computers, at the time it involved much laborious hand calculation. Adams began by assuming a nominal position for the hypothesised body, using the empirical Bode's law. He then calculated the path of Uranus using the assumed position of the perturbing body and calculated the difference between his calculated path and the observations, in modern terms the residuals.
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' is a member of the centaurs, an inward-moving population of bodies transiting from the Kuiper belt to the group of Jupiter- family comets. Their eccentric orbits are often in between those of Jupiter and Neptune, that is, they have a semi-major axis of typically 5.5 to 30.1 AU. Centaurs are cometary-like bodies. They have a short dynamical lifetime due to the perturbing forces exerted on them by the Solar System's outer planets. It orbits the Sun at a distance of 11.2–35.1 AU once every 111 years and 4 months (40,670 days; semi-major axis of 23.15 AU).
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The enhancers comprising super-enhancers share the functions of enhancers, including binding transcription factor proteins, looping to target genes, and activating transcription. Three notable traits of enhancers comprising super-enhancers are their clustering in genomic proximity, their exceptional signal of transcription-regulating proteins, and their high frequency of physical interaction with each other. Perturbing the DNA of enhancers comprising super-enhancers showed a range of effects on the expression of cell identity genes, suggesting a complex relationship between the constituent enhancers. Super-enhancers separated by tens of megabases cluster in three-dimensions inside the nucleus of mouse embryonic stem cells.
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Figure 4: The Moon's gravity differential field at the surface of the Earth is known (along with another and weaker differential effect due to the Sun) as the Tide Generating Force. This is the primary mechanism driving tidal action, explaining two tidal equipotential bulges, and accounting for two high tides per day. In this figure, the Earth is the central blue circle while the Moon is far off to the right. The outward direction of the arrows on the right and left indicates that where the Moon is overhead (or at the nadir) its perturbing force opposes that between the earth and ocean.
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', also known as , is a trans-Neptunian object from the scattered disc of the outermost reaches of the Solar System, approximately 78 kilometers in diameter. It was discovered on 9 September 2015, by the Outer Solar System Origins Survey using the Canada–France–Hawaii Telescope at Mauna Kea Observatories, Hawaii, United States. It is one a small number of detached objects with perihelion distances of 30 AUs or more, and semi-major axes of 200 AU or more.minorplanetcenter.net: q>30, a>200 Such objects can not reach such orbits without some perturbing object, which lead to the speculation of planet nine.
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VW Cephei (VW Cep) is an eclipsing contact binary of W Ursae Majoris-type located roughly at 90.6 light years from the Sun, whose two component stars share a common outer layer. Because the two components share their outer layers, as the components of W Ursae Majoris do, they have the same stellar classification, and are classified as yellow G-type main sequence dwarfs. The components take 0.2783 days (roughly 6.7 hours) to revolve around a common barycentre. Orbital period variations suggest the presence of one more additional perturbing objects of likely low-mass stellar nature.
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Y Sextantis (abbreviated as Y Sex) is a W Ursae Majoris variable eclipsing contact binary star system located roughly at 360 light years from the Sun, whose two component stars share a common outer layer. Because the two components share their outer layers as the components of W Ursae Majoris do, they have the same stellar classification, and are classified as yellow F-type main sequence dwarfs. The components take 0.419822800 days (roughly 10 hours) to revolve around common barycentre. Orbital period variations would suggest the presence of additional perturbing objects, one of them likely substellar.
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Returning spacecraft (including all potentially manned craft) have to find a way of slowing down as much as possible while still in higher atmospheric layers and avoid hitting the ground (lithobraking) or burning up. For many orbital space flights, initial deceleration is provided by the retrofiring of the craft's rocket engines, perturbing the orbit (by lowering perigee down into the atmosphere) onto a suborbital trajectory. Many spacecraft in low-Earth orbit (e.g., nanosatellites or spacecraft that have run out of station keeping fuel or are otherwise non-functional) solve the problem of deceleration from orbital speeds through using atmospheric drag (aerobraking) to provide initial deceleration.
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As a result, the 1254 Ma dates remain the best estimate for the age of initial deposition of the Unkar Group. Geologists have attempted to date the Cardenas Basalt for many years. On the basis of other geologic criteria, geologists have found that the dates, which range from 1,000 to 700 million years ago, obtained for the age of the Cardenas Basalt and upper age of the Unkar Group, were too young, and something was clearly perturbing the dating systematics. The current interpretation is that the deposition of the overlying Chuar Group, in a marine setting, disrupted the potassium-argon (K-Ar) radiometric system.
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Geologists have attempted to date the Cardenas Basalt for many years. On the basis of other geologic criteria, geologists have found that the dates, which range from 700 to 1,000 million years ago, obtained for the age of the Cardenas Basalt and upper age of the Unkar Group were too young and something was clearly perturbing the dating systematics. The current interpretation is that the deposition of the overlying Chuar Group in a marine setting disrupted the potassium-argon (K-Ar) radiometric system. Apparently, fluids associated with the deposition of the Chuar Group have altered the older Cardenas Basalt, partially degraded the minerals, and therefore disrupted the K-Ar systematics.
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Shortly after, a trough situated along 50°W steered Betsy to a more northerly course. Another low- pressure area later formed in the trough, perturbing the ridge to the north of Betsy for much of its initial stages, causing the hurricane's central pressure to rise, despite an increase in sustained winds. However, on September 5, a shortwave forced the low northeastward, allowing for Betsy to strengthen further. Later on September 5, Betsy attained Category 4 hurricane strength, before subsequently reaching peak intensity the following day with winds of and a central pressure of 945 mbar (hPa; 27.91 inHg), based on reconnaissance flights into the system.
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In most practical problems such as planetary motion, however, the interaction potential energy between two bodies is not exactly an inverse square law, but may include an additional central force, a so-called perturbation described by a potential energy . In such cases, the LRL vector rotates slowly in the plane of the orbit, corresponding to a slow apsidal precession of the orbit. By assumption, the perturbing potential is a conservative central force, which implies that the total energy and angular momentum vector L are conserved. Thus, the motion still lies in a plane perpendicular to L and the magnitude is conserved, from the equation .
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As the soul cycles, states Padmanabh Jaini, Jainism traditions believe that it goes through five types of bodies: earth bodies, water bodies, fire bodies, air bodies and vegetable lives. With all human and non-human activities, such as rainfall, agriculture, eating and even breathing, minuscule living beings are taking birth or dying, their souls are believed to be constantly changing bodies. Perturbing, harming or killing any life form, including any human being, is considered a sin in Jainism, with negative karmic effects. A liberated soul in Jainism is one who has gone beyond Saṃsāra, is at the apex, is omniscient, remains there eternally, and is known as a Siddha.
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It is radiating 32% of the luminosity of the Sun from its photosphere at an effective temperature of 4,980 K. In August 2009, this star was found to have a planet via the radial velocity method. The orbital solution shows it to be a Super-Jupiter body in an elliptical orbit with a period of and a typical separation of . A relatively high deviation on the model fit suggests there may be an additional planetary companion in a close, perturbing orbit of the star. The orbital parameters of the known planet does not preclude the existence of an Earth-mass planet with a dynamically-stable orbit in the habitable zone.
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Early in the 19th century, the methods of predicting the motions of the planets were somewhat scattered, having been developed over decades by many different researchers. In 1847, Le Verrier took on the task to "... embrace in a single work the entire planetary system, put everything in harmony if possible, otherwise, declare with certainty that there are as yet unknown causes of perturbations...", a work which would occupy him for the rest of his life. Le Verrier began by re-evaluating, to the 7th order, the technique of calculating the planetary perturbations known as the perturbing function. This derivation, which resulted in 469 mathematical terms, was complete by 1849.
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The fluorophore transduces the recognition event into a measurable optical signal. The use of extrinsic fluorophores, whose emission properties differ widely from those of the intrinsic fluorophores of proteins, tryptophan and tyrosine, enables one to immediately detect and quantify the analyte in complex biological mixtures. The integration of the fluorophore must be done in a site where it is sensitive to the binding of the analyte without perturbing the affinity of the receptor. Antibodies and artificial families of Antigen Binding Proteins (AgBP) are well suited to provide the recognition module of RF biosensors since they can be directed against any antigen (see the paragraph on bioreceptors).
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Planetesimals within the region which would become the asteroid belt were too strongly perturbed by Jupiter's gravity to form a planet. Instead, they continued to orbit the Sun as before, occasionally colliding. In regions where the average velocity of the collisions was too high, the shattering of planetesimals tended to dominate over accretion, preventing the formation of planet-sized bodies. Orbital resonances occurred where the orbital period of an object in the belt formed an integer fraction of the orbital period of Jupiter, perturbing the object into a different orbit; the region lying between the orbits of Mars and Jupiter contains many such orbital resonances.
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After 1978, a number of astronomers kept up the search for Lowell's Planet X, convinced that, because Pluto was no longer a viable candidate, an unseen tenth planet must have been perturbing the outer planets. In the 1980s and 1990s, Robert Harrington led a search to determine the real cause of the apparent irregularities.Croswell, pp. 56–71 He calculated that any Planet X would be at roughly three times the distance of Neptune from the Sun; its orbit would be highly eccentric, and strongly inclined to the ecliptic—the planet's orbit would be at roughly a 32-degree angle from the orbital plane of the other known planets.
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Besides the galactic tide, the main trigger for sending comets into the inner Solar System is thought to be interaction between the Sun's Oort cloud and the gravitational fields of nearby stars or giant molecular clouds. The orbit of the Sun through the plane of the Milky Way sometimes brings it in relatively close proximity to other stellar systems. For example, it is hypothesized that 70 thousand years ago, perhaps Scholz's Star passed through the outer Oort cloud (although its low mass and high relative velocity limited its effect). During the next 10 million years the known star with the greatest possibility of perturbing the Oort cloud is Gliese 710.
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In this context commensurability means that the ratio of the two planets' mean motions is very nearly equal to a ratio between a pair of small whole numbers. Two periods of Saturn's orbit around the Sun almost equal five of Jupiter's. The corresponding difference between multiples of the mean motions, , corresponds to a period of nearly 900 years, and it occurs as a small divisor in the integration of a very small perturbing force with this same period. As a result, the integrated perturbations with this period are disproportionately large, about 0.8° degrees of arc in orbital longitude for Saturn and about 0.3° for Jupiter.
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Investigations in 2010 and 2011 found that the orbital period of the two stars in UZ Fornacis varied cyclically. Researchers attributed this to two possible gas giant sized planets around the two stars, perturbing their orbits and causing the orbital period to vary. As of 2019, there is not enough information to explain all of the period variations, since the planets would have to be in eccentric orbits to fit the data, and that would cause the orbits to be dynamically unstable. It is possible that there are even more planets causing additional perturbation, or some physical effect such as the Applegate mechanism is responsible for the eclipse timing variations.
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', is a trans-Neptunian object discovered by Cerro Tololo Observatory, La Serena, Chile on September 28, 2003. It is one of a small number of detached objects with perihelion distances of 30 AUs or more, and semi-major axes of 200 AU or more.minorplanetcenter.net: q>30, a>150 It is thought that objects cannot reach such orbits without some perturbing object outside the eight planets, which has led to the speculation of Planet Nine. A search of SDSS images of the region where would have been in 2001 turned up no conclusive detections of the object, indicating it is either much dimmer than expected or on a very different orbit.
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This minor planet is one a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 200 AU or more.minorplanetcenter.net: q>30, a>150 Such objects can not reach such orbits without some perturbing object, which lead to the speculation of planet nine. Based on an absolute magnitude of approximately 7.95 and an assumed albedo of 0.09, the Johnston's Archive calculated a mean-diameter of 117 kilometers. is located very near the 1:12 Neptune resonance of 157.8 AU (compared to its 157.2 ± 0.6 AU), meaning that it completes roughly 1 orbit for every 12 orbits Neptune makes.
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Plant's lab goals include to measure the kinetic constants for those fluctuations, and the correlations between them, to provide a thermodynamic basis for understanding which cellular measurands are the most important for controlling a particular phenotype. This work is motivated by a critical challenge in characterizing cell-based therapies, namely what should be measured that will provide predictive information about the cell product to assure desirable functionality. Carrying out this study involves a large number of NIST collaborators to address challenges in rapid non-perturbing quantitative imaging, CRISPR-Cas genome editing of reporter iPSC lines, image analysis including the use of CNN inference, and theoretical modeling.
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This is an A-type main sequence star with a stellar classification of A3 V. It has an estimated 2.9 times the mass of the Sun and around 2.2 times the Sun's radius. With an age of 403 million years, it has a high rate of spin with a projected rotational velocity of 133 km/s. It is radiating 23 times the solar luminosity from its photosphere at an effective temperature of 8,917 K. Upsilon Serpentis is a suspected astrometric binary, which means an undetected companion is perturbing the motion of the visible star. An X-ray emission has been detected from this system with a luminosity of .
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In 2018, analysis of the Gaia (spacecraft) second data release (DR2) revealed significant proper motion anomalies in the orbits of the binary stars around each other; the stars were not quite orbiting around their centre of mass with 61 Cygni B also orbiting too slowly for its assumed mass. These anomalies taken together are indicative of the possible presence of a perturbing third object in orbit around 61 Cygni B. The habitable zone for 61 Cygni A, defined as the locations where liquid water could be present on an Earth-like planet, is 0.26–0.58 AU. For 61 Cygni B, the habitable zone is 0.24–0.50 AU.
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This, he believes, is structured around three narrative solutions, the first of which is a "perturbing situation"—here, the "extremely difficult journey" undertaken by the boy prince. The initial event is closely followed by a set of challenges invoking the action of forces larger than human life, "a whirlpool of events whose onset [the hero] cannot control, but which he dominates with support from supernatural beings and magical objects". A third element, the happy ending, consecrates the victory of good over evil, and often distributes justice in an uncompromising and violent form. Braga also sees "Harap Alb" as a peak among its author's literary contributions, ranking it above writings with similar pretexts such as The Story of the Pig.
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In most situations, it is convenient to set each of these curves tangent to the trajectory at the point of intersection. Curves that obey this condition (and also the further condition that they have the same curvature at the point of tangency as would be produced by the object's gravity towards the central body in the absence of perturbing forces) are called osculating, while the variables parameterising these curves are called osculating elements. In some situations, description of orbital motion can be simplified and approximated by choosing orbital elements that are not osculating. Also, in some situations, the standard (Lagrange-type or Delaunay-type) equations furnish orbital elements that turn out to be non-osculating.
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Let us now consider small departures from the circular motion of the orbiting mass element caused by some perturbing force. We transform variables into a rotating frame moving with the orbiting mass element at angular velocity \Omega(R_0)=\Omega_0\ , with origin located at the unperturbed, orbiting location of the mass element. As usual when working in a rotating frame, we need to add to the equations of motion a Coriolis force -2\boldsymbol\Omega_0\times\boldsymbol v plus a centrifugal force R\Omega_0^2\ . The velocity v is the velocity as measured in the rotating frame. Furthermore, we restrict our attention to a small neighborhood near R_0\ , say R_0+x\ , with x much smaller than R_0\ .
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However the accuracy of the lunar theory was low, due to the perturbing effect of the Sun and planets on the motion of the Moon around the Earth. Jean le Rond d'Alembert and Alexis Clairaut, who developed a longstanding rivalry, both attempted to analyze the problem in some degree of generality; they submitted their competing first analyses to the Académie Royale des Sciences in 1747.The 1747 memoirs of both parties can be read in the volume of Histoires (including Mémoires) of the Académie Royale des Sciences for 1745 (belatedly published in Paris in 1749) (in French): : Clairaut: "On the System of the World, according to the principles of Universal Gravitation" (at pp.
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A planet massive enough to open a gap in a gaseous disk undergoes a regime referred to as Type II disk migration. When the mass of a perturbing planet is large enough, the tidal torque it exerts on the gas transfers angular momentum to the gas exterior of the planet's orbit, and does the opposite interior to the planet, thereby repelling gas from around the orbit. In a Type I regime, viscous torques can efficiently counter this effect by resupplying gas and smoothing out sharp density gradients. But when the torques become strong enough to overcome the viscous torques in the vicinity of the planet's orbit, a lower density annular gap is created.
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It is one a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 250 AU or more. Such objects cannot reach such orbits without some perturbing object, which has led to the Planet Nine hypothesis, that a massive trans-Neptunian planet is the perturber. However is an interesting outlier of these trans- Neptunian objects that make one of the lines of evidence for Planet Nine. Unlike the others, the shape of whose orbits (longitudes of perihelion) either cluster in anti-alignment with the modeled orbit of Planet Nine or cluster in alignment with it, 's major axis is almost at a right angle to that of the putative planet.
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In this model, the assumption is made that the interaction between the conduction electrons and the ion cores can be modeled through the use of a "weak" perturbing potential. This may seem like a severe approximation, for the Coulomb attraction between these two particles of opposite charge can be quite significant at short distances. It can be partially justified, however, by noting two important properties of the quantum mechanical system: #The force between the ions and the electrons is greatest at very small distances. However, the conduction electrons are not "allowed" to get this close to the ion cores due to the Pauli exclusion principle: the orbitals closest to the ion core are already occupied by the core electrons.
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Thus the use of stable isotopes became commonplace with the increasing availability of isotopically-enriched materials and inorganic mass spectrometers. The use of stable isotopes instead of radioisotopes does have several drawbacks: larger quantities of tracer are required, having the potential of perturbing the naturally existing mineral; analytical sample preparation is more complex and mass spectrometry instrumentation more costly; the presence of tracer in whole bodies or particular tissues cannot be measured externally. Nonetheless, the advantages have prevailed making stable isotopes the standard in human studies. Most of the minerals that are essential for human health and of particular interest to nutrition researchers have stable isotopes, some well- suited as biological tracers because of their low natural abundance.
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Bump mapping, normal mapping and parallax mapping are techniques applied to textures in 3D rendering applications such as video games to simulate bumps and wrinkles on the surface of an object without using more polygons. To the end user, this means that textures such as stone walls will have more apparent depth and thus greater realism with less of an influence on the performance of the simulation. Bump mapping is achieved by perturbing the surface normals of an object and using a grayscale image and the perturbed normal during illumination calculations. The result is an apparently bumpy surface rather than a perfectly smooth surface although the surface of the underlying object is not actually changed.
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The cure then involved a process of opposition, of struggle and domination, of the patient's troubled will by the healthy will of the physician. It was thought the confrontation would lead not only to bring the illness into broad daylight by its resistance, but also to the victory of the sound will and the renunciation of the disturbed will. We must apply a perturbing method, to break the spasm by means of the spasm.... We must subjugate the whole character of some patients, subdue their transports, break their pride, while we must stimulate and encourage the others (Esquirol, J.E.D., 1816De la Folie. Chapter 5: Traitement de la folie, pp 132-133: in Foucault (1997), p. 43).
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Book 1 contains some proofs with little connection to real-world dynamics. But there are also sections with far-reaching application to the solar system and universe: Propositions 57–69 deal with the "motion of bodies drawn to one another by centripetal forces". This section is of primary interest for its application to the Solar System, and includes Proposition 66 along with its 22 corollaries: here Newton took the first steps in the definition and study of the problem of the movements of three massive bodies subject to their mutually perturbing gravitational attractions, a problem which later gained name and fame (among other reasons, for its great difficulty) as the three-body problem. Propositions 70–84 deal with the attractive forces of spherical bodies.
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Adams certainly gave Challis no detailed calculations and Challis was unimpressed by the description of his method of successively approximating the position of the body, being disinclined to start a laborious observational programme at the observatory, remarking "while the labour was certain, success appeared to be so uncertain." Urbain Jean-Joseph Le Verrier. Meanwhile, Urbain Le Verrier, on November 10, 1845, presented to the Académie des sciences in Paris a memoir on Uranus, showing that the pre-existing theory failed to account for its motion. Unaware of Adams's work, he attempted a similar investigation, and on June 1, 1846, in a second memoir presented to a public meeting of the Académie, gave the position, but not the mass or orbit, of the proposed perturbing body.
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The galaxy shows an enhanced rate of star formation that may have been triggered by a collision with a dwarf galaxy, or by the gravitational interaction with its neighbor compressing gas and dust. It was discovered by Friedrich August Theodor Winnecke in 1876. In the Atlas of Peculiar Galaxies, the galaxy is mentioned twice, once as Arp 25, in the category spiral galaxies with one heavy arm, and one more time as Arp 114, in the category elliptical galaxies close to and perturbing spiral galaxies, in pair with NGC 2300. NGC 2276 has been home to six supernovae in the last 60 years; SN 1962Q (mag 16.9), SN 1968V (mag 15.7), SN 1968W (mag 16.6), SN 1993X (type II, mag.
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Early computer-generated models of planetary formation predicted the existence of terrestrial planets around both Alpha Centauri A and B,See Lissauer and Quintana in references below. but most recent numerical investigations have shown that the gravitational pull of the companion star renders the accretion of planets difficult. Despite these difficulties, given the similarities to the Sun in spectral types, star type, age and probable stability of the orbits, it has been suggested that this stellar system could hold one of the best possibilities for harbouring extraterrestrial life on a potential planet. In the Solar System, Jupiter and Saturn were probably crucial in perturbing comets into the inner Solar System, providing the inner planets with a source of water and various other ices.
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Although other reflectivity techniques (in particular optical reflectivity, x-ray reflectometry) operate using the same general principles, neutron measurements are advantageous in a few significant ways. Most notably, since the technique probes nuclear contrast, rather than electron density, it is more sensitive for measuring some elements, especially lighter elements (hydrogen, carbon, nitrogen, oxygen, etc.). Sensitivity to isotopes also allows contrast to be greatly (and selectively) enhanced for some systems of interest using isotopic substitution, and multiple experiments that differ only by isotopic substitution can be used to resolve the phase problem that is general to scattering techniques. Finally, neutrons are highly penetrating and typically non-perturbing: which allows for great flexibility in sample environments, and the use of delicate sample materials (e.g.
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By analogy, the subset of the Cartesian product X×X of any set X with itself, consisting of all pairs (x,x), is called the diagonal, and is the graph of the equality relation on X or equivalently the graph of the identity function from X to x. This plays an important part in geometry; for example, the fixed points of a mapping F from X to itself may be obtained by intersecting the graph of F with the diagonal. In geometric studies, the idea of intersecting the diagonal with itself is common, not directly, but by perturbing it within an equivalence class. This is related at a deep level with the Euler characteristic and the zeros of vector fields.
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Keefe also complained that the program suggested that Saakashvili had held discussions with the British Prime Minister Gordon Brown about the "non-existent events described", and stated that neither he, nor the British government had any involvement in or previous knowledge of, what he called, Imedi's irresponsible programme. The Ambassador also demanded that Imedi apologise and make it clear that it used his image without his consent or permission. United States Ambassador to Georgia John Bass called the broadcast irresponsible and perturbing, and said it was not helpful in improving the security situation in the region. The European Union Monitoring Mission in Georgia stated that the airing of the program was irresponsible and had the potential to further destabilise the region, with the possibility of a resumption of military actions between Russian and Georgian troops.
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In astronomy, an equinox is either of two places on the celestial sphere at which the ecliptic intersects the celestial equator. Although there are two intersections of the ecliptic with the celestial equator, by convention, the equinox associated with the Sun's ascending node is used as the origin of celestial coordinate systems and referred to simply as "the equinox". In contrast to the common usage of spring/vernal and autumnal equinoxes, the celestial coordinate system equinox is a direction in space rather than a moment in time. In a cycle of about 25,700 years, the equinox moves westward with respect to the celestial sphere because of perturbing forces; therefore, in order to define a coordinate system, it is necessary to specify the date for which the equinox is chosen.
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Signature of M. LeVerrier Le Verrier's most famous achievement is his prediction of the existence of the then unknown planet Neptune, using only mathematics and astronomical observations of the known planet Uranus. Encouraged by physicist Arago,Arago summary Director of the Paris Observatory, Le Verrier was intensely engaged for months in complex calculations to explain small but systematic discrepancies between Uranus's observed orbit and the one predicted from the laws of gravity of Newton. At the same time, but unknown to Le Verrier, similar calculations were made by John Couch Adams in England. Le Verrier announced his final predicted position for Uranus's unseen perturbing planet publicly to the French Academy on 31 August 1846, two days before Adams's final solution was privately mailed to the Royal Greenwich Observatory.
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The CLS was the first light source to use a superconducting RF (SRF) cavity in the storage ring from the beginning of operations. The niobium cavity is based on the 500 MHz design used at the Cornell Electron Storage Ring (CESR) which allows potentially beam-perturbing high order modes to propagate out of the cavity where they can be very effectively damped. The superconducting nature of the niobium cavity means only 0.02% of the RF power put into the cavity is wasted in heating the cavity as compared to roughly 40% for normal-conducting (copper) cavities. However, a large portion of this power saving - about 160 kW out of the 250 kW saved - is needed to power the cryogenic plant required to supply liquid helium to the cavity.
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In 1821, Alexis Bouvard had published astronomical tables of the orbit of Uranus, making predictions of future positions based on Newton's laws of motion and gravitation.Bouvard (1821) Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesize some perturbing body.[Anon.] (2001) "Bouvard, Alexis", Encyclopædia Britannica, Deluxe CDROM edition These irregularities or "residuals", both in the planet's ecliptic longitude and in its distance from the Sun, or radius vector, might be explained by a number of hypotheses: the effect of the Sun's gravity, at such a great distance might differ from Newton's description; or the discrepancies might simply be observational error; or perhaps Uranus was being pulled, or perturbed, by an as-yet undiscovered planet. At position a, Neptune gravitationally perturbs the orbit of Uranus, pulling it ahead of the predicted location.
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This is done by repeatedly randomly perturbing the structure of the proteins around specified design positions, identifying the lowest energy combination of rotamers, and determining whether the new design has a lower binding energy than prior ones.The iterative nature of this process allows IPRO to make additive mutations to a protein sequence that collectively improve the specificity toward desired substrates and/or cofactors. Details on how to download the software, implemented in Python, and experimental testing of predictions are outlined in this paper: Computation-aided design has also been used to engineer complex properties of a highly ordered nano-protein assembly. A protein cage, E. coli bacterioferritin (EcBfr), which naturally shows structural instability and an incomplete self-assembly behavior by populating two oligomerization states, is the model protein in this study.
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The N-terminal EF-hand domain of RLC binds calcium/magnesium at activating concentrations, however the dissociation rate is too slow to modulate cardiac contractility on a beat- by-beat basis. Perturbing the calcium binding region of RLC through site- directed mutagenesis (D47A) decreased tension and stiffness in isolated, skinned skeletal muscle fibers, suggesting that the conformational change induced by calcium binding to RLC is functionally important. Another mode of RLC modulation lies in its ability to be modified by phosphorylation and deamidation in the N-terminal region, resulting in significant charge alterations of the protein. RLC is phosphorylated by a cardiac-specific myosin light chain kinase (MYLK3), which was recently cloned. Studies have supported a role for myosin phosphatase targeting subunit 2 (MYPT2,PPP1R12B) in the dephosphorylation of RLC.
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In these methods, it is considered that the body is always moving in a conic section, however the conic section is constantly changing due to the perturbations. If all perturbations were to cease at any particular instant, the body would continue in this (now unchanging) conic section indefinitely; this conic is known as the osculating orbit and its orbital elements at any particular time are what are sought by the methods of general perturbations. General perturbations takes advantage of the fact that in many problems of celestial mechanics, the two-body orbit changes rather slowly due to the perturbations; the two-body orbit is a good first approximation. General perturbations is applicable only if the perturbing forces are about one order of magnitude smaller, or less, than the gravitational force of the primary body.
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337 All preambles contain the following phrase: Damen comments that here the treason definition from the treason statutes of the States of Holland and the States General of the late 1580s and early 1590s is extended from "perturbation of the public order" to "perturbation of the stance of the religion" and hence of the Church. In other words, the court could have convicted the defendants for "perturbing public order" as a consequence of "sustaining pernicious maxims" (the Remonstrant theses that had at the time recently been condemned as "heretical" by the Synod of Dort), but instead the court opted for declaring the "perturbation" of the Church as itself "treasonous." This amounted to "legislating from the bench" as this was an entirely new element of the Dutch law of treason as it existed since the 1590s.Damen, p.
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Learning implies that the previous history, for example the memory about the previously found local minima, is mined to produce better and better starting points for local search. The implicit assumption is that of a clustered distribution of local minima: when minimizing a function, determining good local minima is easier when starting from a local minimum with a low value than when starting from a random point. The only caveat is to avoid confinement in a given attraction basin, so that the kick to transform a local minimizer into the starting point for the next run has to be appropriately strong, but not too strong to avoid reverting to memory-less random restarts. Iterated Local Search is based on building a sequence of locally optimal solutions by: # perturbing the current local minimum; # applying local search after starting from the modified solution.
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Observational evidence for this galaxy was presented in 2015, based on the claimed discovery of four Cepheid variable stars by Sukanya Chakrabarti (RIT) and collaborators. Search for the stars was motivated by an earlier study that linked a warp in the HI (atomic hydrogen) disk of the Milky Way Galaxy to the tidal effects of a perturbing galaxy. The unseen perturber's mass was calculated to be about 1%approximately 10 billion solar masses of that of the Milky Way, which would make it the third heaviest satellite of the Milky Way, after the Magellanic Clouds (Large Magellanic Cloud and Small Magellanic Cloud, each some 10x larger than Galaxy X). In this hypothetical model, the putative satellite galaxy would have interacted with the Milky Way some 600 million years ago, coming as close as , and would now be moving away from the Milky Way.
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It was further proposed to excite an electronic shell state, to achieve 'good' quantum numbers of the total system of the shell plus nucleus that will lead to a reduction of the influence induced by external perturbing fields. A central idea is to probe the successful laser excitation of the nuclear state via the hyperfine- structure shift induced into the electronic shell due to the different nuclear spins of ground- and excited state. This method is known as the double- resonance method. The expected performance of a single-ion nuclear clock was further investigated in 2012 by C. Campbell et al. with the result that a systematic frequency uncertainty (accuracy) of the clock of 1.5·10−19 could be achieved, which would be by about an order of magnitude better than the accuracy achieved by the best optical atomic clocks today.
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Several elliptical rings of material have been observed in the outer regions of the debris disk between 500 and 800 AU: these may have formed as a result of the system being disrupted by a passing star. Astrometric data from the Hipparcos mission reveal that the red giant star Beta Columbae passed within 2 light years of Beta Pictoris about 110,000 years ago, but a larger perturbation would have been caused by Zeta Doradus, which passed at a distance of 3 light years about 350,000 years ago. However computer simulations favor a lower encounter velocity than either of these two candidates, which suggest that the star responsible for the rings may have been a companion star of Beta Pictoris on an unstable orbit. The simulations suggest a perturbing star with a mass of 0.5 solar masses is likely to blame for the structures.
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Just as the Moon raises two water tides on opposite sides of the Earth, so a galactic tide produces two arms in its galactic companion. While a large tail is formed if the perturbed galaxy is equal to or less massive than its partner, if it is significantly more massive than the perturbing galaxy, then the trailing arm will be relatively minor, and the leading arm, sometimes called a bridge, will be more prominent. Tidal bridges are typically harder to distinguish than tidal tails: in the first instance, the bridge may be absorbed by the passing galaxy or the resulting merged galaxy, making it visible for a shorter duration than a typical large tail. Secondly, if one of the two galaxies is in the foreground, then the second galaxy — and the bridge between them — may be partially obscured.
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Newton's theorem of revolving orbits was his first attempt to understand apsidal precession quantitatively. According to this theorem, the addition of a particular type of central force—the inverse-cube force—can produce a rotating orbit; the angular speed is multiplied by a factor k, whereas the radial motion is left unchanged. However, this theorem is restricted to a specific type of force that may not be relevant; several perturbing inverse- square interactions (such as those of other planets) seem unlikely to sum exactly to an inverse-cube force. To make his theorem applicable to other types of forces, Newton found the best approximation of an arbitrary central force F(r) to an inverse-cube potential in the limit of nearly circular orbits, that is, elliptical orbits of low eccentricity, as is indeed true for most orbits in the Solar System.
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In relativistic cosmology using the Lagrangian threading dynamics of Ehlers (1971)Ehlers J (1971) General Relativity and Cosmology (Varenna), R K Sachs (Academic Press NY) and Ellis (1971)Ellis G F R, (1971) General Relativity and Cosmology(Varenna), R K Sachs (Academic Press NY) it is usual to use the gauge-invariant covariant perturbation theory developed by Hawking (1966)Hawking S W (1966) ApJ. 145, 44 and Ellis and Bruni (1989). Here rather than starting with a background and perturbing away from that background one starts with full general relativity and systematically reduces the theory down to one that is linear around a particular background. The approach is local and both covariant as well as gauge invariant but can be non-linear because the approach is built around the local comoving observer frame (see frame bundle) which is used to thread the entire space-time.
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Variational orbit: nearly an ellipse, with the Earth at the center. The diagram illustrates the perturbing effect of the Sun on the Moon's orbit, using some simplifying approximations, e.g. that in the absence of the Sun, the Moon's orbit would be circular with the Earth at its center In 1687 Newton published, in the 'Principia', his first steps in the gravitational analysis of the motion of three mutually-attracting bodies. This included a proof that the Variation is one of the results of the perturbation of the motion of the Moon caused by the action of the Sun, and that one of the effects is to distort the Moon's orbit in a practically elliptical manner (ignoring at this point the eccentricity of the Moon's orbit), with the centre of the ellipse occupied by the Earth, and the major axis perpendicular to a line drawn between the Earth and Sun.
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With the narrow-field mode, MUSE will be able to zoom in on the region around the super-massive black hole at the centre of massive galaxies. It is hoped that this will help astronomers understand the process by which these giants formed - likely through a merging process whereby two black holes coalesce to form a more massive end product and at the same time perturbing the stellar orbits in the centre of the galaxy. At higher redshift MUSE will provide the power to construct maps of the distribution of metals in galaxies and at the same time provide constraints on the dynamical structure of these objects. Combining this with environmental information due to the wide field of view (1 arcminute corresponds to 430 kilo-parsec at a redshift of 0.7) it will be possible to study how the properties of galaxies are affected by the environment they find themselves in a very powerful, and mostly new, way.
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The gravitational problem of three bodies in its traditional sense dates in substance from 1687, when Isaac Newton published his Principia (Philosophiæ Naturalis Principia Mathematica). In Proposition 66 of Book 1 of the Principia, and its 22 Corollaries, Newton took the first steps in the definition and study of the problem of the movements of three massive bodies subject to their mutually perturbing gravitational attractions. In Propositions 25 to 35 of Book 3, Newton also took the first steps in applying his results of Proposition 66 to the lunar theory, the motion of the Moon under the gravitational influence of the Earth and the Sun. The physical problem was addressed by Amerigo Vespucci and subsequently by Galileo Galilei; in 1499, Vespucci used knowledge of the position of the Moon to determine his position in Brazil. It became of technical importance in the 1720s, as an accurate solution would be applicable to navigation, specifically for the determination of longitude at sea, solved in practice by John Harrison's invention of the marine chronometer.
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The Laplace or Laplacean plane, as discussed here, relates to the orbit of a planetary satellite. It is to be distinguished from another and quite different plane, also discovered by Laplace, and which is also sometimes called the "Laplacian" or "Laplace plane", but more often the invariable plane (or the "invariable plane of Laplace"). The invariable plane is simply derived from the sum of angular momenta, and is "invariable" over the entire system, while the Laplace plane may be different for different orbiting objects within a system. Confusingly, a satellite's Laplace plane (as defined here) is also sometimes called its "invariable plane". The Laplace plane is a result of perturbational effects, which were discovered by Laplace while he was investigating the orbits of Jupiter’s principal moons (the Galilean satellites of Jupiter). Laplace found that the effects of the solar perturbing force, and of the planet’s oblateness (its equatorial bulge), together gave rise to an "inclinaison propre", an "own inclination", in the plane of the satellite orbits, relative to the plane of Jupiter’s equator.
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Călinescu, p.481-482 In his view, the work became "a drama of maternity" and a fable using characteristic anthropomorphism ("the devices of La Fontaine").Călinescu, p.482 In this context, he noted, the tale also provided a comedic "analogy between the animal and the human worlds", with "symbols-caricatures": the goat "with many utters and a bleating voice" as "a caricature of motherhood which nature itself has provided", but also as "the garrulous and whiny woman"; the wolf as a "man without scruples." Literary historian Mircea Braga explored the narrative in order to locate themes he argues are characteristic for both Creangă's work and Romanian folklore: the "perturbing situation" (in this case, the departure of the goat and the unusual responsibility bestowed on her sons), the rite of passage trial (testing the kids' ability to hide from the path of danger) and the happy ending as a triumph of the good, which often involves a positive reply to each of the evil deeds preceding it (the mock- feast organized by goat).Mircea Braga, postface to Ion Creangă, Poveşti şi povestiri, Editura Minerva, 1987, p.
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On the purely visual level, Hoolboom notes Cockburn's montage consists of deliberately banal images, "indifferently shot and largely illustrative of the voice-over" to emphasize the fact that, to all appearances and for all practical purposes, nothing has changed. Norman Wilner notes that as is typical of him, Cockburn's narrator is both prankster and serious inquisitor, calmly offering philosophical and metaphysical insights while his thesis plays out on the screen; "there's no way anything he's talking about is even plausible, let alone probable, but he's going to explore the possibilities as if it were." Treating the narrator exclusively as a persona, Martinson remarks that he is both rattled by and curious about the uniquely private and perturbing knowledge that he has mysteriously acquired, and, if we take the narrator at his word, a universal expansion is reducible to "a blip in the order of things, barely perceptable." The narrator is certain about what happened and yet nervous about it at the same time, aware that the "residue" of the event exists "only in this mind" in the form of a "barely sensed sense" which, having happened once, may happen again.
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