There are multistep tests and the weighing of various factors.
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Applicants must pass a highly competitive, multistep process to become a PAL.
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According to Ms. Cho, a multistep skin-care routine is the secret.
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Previously, installing a custom font onto iOS devices was a painstaking multistep process.
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Me Time Why the multistep Japanese scalp facial could become your new obsession.
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The first area relates to what the Treasury refers to as multistep acquisitions.
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The auction will be a multistep process aimed for completion in the late fall.
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At WeWork, Ms. Berrent said, arbitration is part of a multistep process to resolve disputes.
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To make a memory requires completing a multistep process: attention, perceiving, encoding, consolidation and recalling.
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Multistep transactions are often "stepped together" and treated as a single transaction for tax purposes.
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Clyburn said that, like the civil rights movement, criminal justice reform would be a multistep process.
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Some patients died during laborious, multistep transfers, and some doctors felt the ship left too soon.
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It's something of an art form -- a timed, multistep process that can involve some light singing.
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But the decision to require a multistep opt-in process has alarmed some of Alaska's state employees.
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Receiving reparations in cases like these is a multistep process that the S.E.C. details on the site.
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The mechanism is a far cry, he noted, from the complicated, multistep process by which modern cells divide.
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Google initially announced it was following the footsteps of Amazon and adding multistep smart home routines last October.
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Still, he has kept one foot in Korea, which is now known worldwide for its multistep skin care.
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In a multistep process, PBT fibers are taped, cut, and curled into a ready-to-glue lash extension.
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In the new study, the authors conducted a multistep investigation that brought together biology, computer science, mathematics and physics.
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It's a complicated multistep process, with molds and models needed to recreate the actual thumb print once they're digitally lifted.
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It seems like a simple question, but answering it required a multistep investigation by a trio of Caltech graduate students.
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It's getting a new feature called Shortcuts, which is basically a way to get Siri to go through a multistep routine.
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"This is an important first step on the multistep road to developing a universal flu vaccine," institute Director Dr. Anthony Fauci.
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Once a complaint has been made, a multistep timeline steers the process that follows: First, CWG is notified of the complaint immediately.
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It can't handle the sort of multistep logic that connects Qualcomm's success on NXP to U.S. dominance in 5G to ZTE's survival.
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"There is a multistep procedure before a state might lose federal funding," said Jon W. Davidson, the legal director of Lambda Legal.
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Still, Mr. Monteiro and Mr. Sibley described Facebook's reporting process as a cumbersome multistep procedure that can change from day to day.
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"This is a multistep process," Senator Patrick J. Leahy of Vermont, the senior Democrat on the Senate Appropriations Committee, said on Monday.
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You can save even more steps by setting up macros: multistep sequences you can trigger with a single command, even a spoken one.
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"For tasks with a multistep sequence, talking to yourself out loud can help you keep out distractions and remind yourself where you are."
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It's a multistep procedure where a medical team removes eggs from a woman's ovaries, and then fertilizes the eggs with sperm in a laboratory.
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That's because getting the phone going requires a multistep process: After unfolding the device, you scan a fingerprint or your face to unlock it.
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He argued that some players could be pushed to return a little sooner from the multistep rehabilitation process that is standard across the sport.
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But dreamers, named for the failed DREAM Act, which had proposed a multistep process to permanent residency, are dealing with those fears in different ways.
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Once the lander hits the top of Mars' atmosphere, it will perform a complicated multistep landing routine that will last between six and seven minutes.
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In light of these upgrades, maybe Siri can start to feel relevant again, especially as its rivals already have the ability to perform multistep routines.
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The guidance on multistep acquisition relates to a new trend that was hard to predict in advance: Many inverted companies have proved to be recidivists.
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One step in a multistep cleaning process was missed by a technician, possibly contaminating the surgical equipment, said Liz Fisher, marketing specialist for Goshen Health.
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It's a combination of six to eight steps that I've perfected over the past year, undeniably rooted in the multistep skin-care practices of Korean beauty.
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Alexa doesn't really have an answer to Google's multiple actions, apart from multistep routines, in which a specific phrase, like "good morning" can trigger multiple actions.
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Attorney General William Barr needs to follow a multistep redaction process before he can release additional details from Robert Mueller's report on the Russia probe, Sen.
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Even though platinum requires a ton of bleach and rainbow is a multistep process, becoming a redhead always felt like the most extreme hair color transformation possible.
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Oh, and every time I try and sift through the phone it freezes, to the point where even making a quick call is a complicated, multistep process.
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Even when it can be done, it can be a multistep process of downloading new data to a flash drive and then transferring it to the vehicle.
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Homework is a drag for any high schooler, but for the class of 2006's Laura Palmaro Allen, even starting an assignment required a laborious, multistep process.
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That said, while Disney has a tremendous library of content to pull from across its long history, moving everything to the service will be a multistep, gradual process.
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Similar to Homewise, the Texas nonprofit offers a multistep program, from financial education to building and selling property at roughly cost, or no more than 10 percent profit.
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Siri's new Shortcuts feature is now available to download for iOS 12 users, and it allows iPhone and Apple Watch users to use Siri to step through multistep routines.
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The Treasury's new administrative guidance that was released on Monday tackles a wide range of tax issues related to inversions, including new approaches to multistep acquisitions and earnings-stripping.
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Trends have changed, too — skin-care routines have become so much more complicated and multistep, but I remain skeptical that we need to layer so many products onto our skin.
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The multistep Dendrite test calls for courts, in the final step of their analysis, to balance the First Amendment rights of anonymous posters against the necessity of exposing their identities.
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Monotypes are all surface, all skin, quickly brushed onto metal or glass before the ink dries — no labor-intensive carving, no multistep acid bath as required by other printmaking techniques.
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Beyond that, the disease usually involves a decline in other cognitive abilities: planning a schedule, following multistep directions, carrying out familiar logistical tasks like balancing a checkbook or cooking a meal.
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It's not always perfect — some laptops still have multistep boots even with a sensor, or a fingerprint won't read and you'll have to lift and press again, which ruins the magic.
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"The fact that this was a multistep malicious intrusion, a downloading of data, and extortionate demands means this wasn't consistent with the way that [the bug bounty] program normally operates," Flynn testified.
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"The idea is to orient your body to the ground so when you hit, there's a multistep process of hitting and shifting your body weight to break up that impact," said Sgt.
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Along an assembly line made of three segments, an engineered knit fabric was laser-cut (by robots), shaped and sewn (by humans), and fused into soles (a collaborative, multistep, human-and-machine process).
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But the idea is it's a multistep process to attain more leverage with which to force China to allow American companies to sell their goods and operate freely, without having their technology stolen.
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No. Republicans have embarked on a fragile, multistep process to repeal major parts of the health care law, one that is on pace to at least take weeks, even without any big stumbles.
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You'll get familiarized with the ICE method (Impact, Confidence, Ease), a multistep technique for scrutinizing a brand's marketing needs and discover the many ways in which you can communicate with online consumers effectively.
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Google has shown it's thinking along these lines with its Duplex tech, and Apple is pursuing greater complexity through its new Shortcuts app, which allows users to set up complex, multistep instructions using Siri.
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As he opened a long-awaited trade action against China, Mr. Trump used uncharacteristically restrained language and a multistep bureaucratic process that will likely put off punitive steps against Beijing for months, if not forever.
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Symmetry doesn't yet exist on the desktop app — there are workarounds to do this on the desktop through multistep processes or third-party plug-ins, but it's one of the most requested features in Illustrator.
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My partner was so stymied by the multistep, incredibly (and purposefully) confusing process of submitting insurance reimbursement forms for every single week of therapy that for months he just didn't send them — and ate over $1,000.
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On Monday, the Lloyd D. Nabors Demolition team, which initially imploded the building with explosives, began "a multistep process that is both safe and effective," using a large crane and wrecking ball to topple the tower.
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It is a complicated multistep procedure that requires up to five people working together for an extended period of time with a number of safety risks due to the size and weight of the tires and tools.
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All these activities, each part of the multistep process, center around a vast field, where fabrics — in indigo, madder, saffron and hot pink — are laid out to dry or hung from the rooftops of the surrounding buildings.
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"As is always the case, we listened to the advice of our national security agencies throughout the multistep national security review process under the Investment Canada Act," Navdeep Bains, the Canadian minister of innovation, said in a statement.
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The districts vary in size and operation, and they must be authorized by the city through a multistep process that typically takes two years and requires support from property owners, businesses and residents in that area, officials said.
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Twitch Studio was designed to hide the traditional multistep process it takes to stream — to hide the complexities of configuring your hardware, software, and network connection — in order to allow potential streamers to get started as soon as possible.
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"I feel equipped to help you against the Roses of the world, because I have represented so many of them," Ms. Bloom wrote, before laying out a multistep playbook for how to intimidate accusers or paint them as liars.
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He laid out a multistep plan: converting all energy to electricity and heat, and generating both solely with wind, solar and water resources; heating and cooling buildings with electric heat pumps; and powering factories with furnaces that use electricity.
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This multistep process includes: imagining her outside work, perhaps interacting with her children or taking a walk in the woods; imagining her insecurities, her disappointments; thinking about the people who care for her or a family member who needs her.
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Mr. Fender then tracked down Jill Goldman, a genetic counselor specializing in dementia at the Taub Institute at Columbia University Medical Center, who described a multistep process of counseling and confirmatory testing that's been the standard of care for 260 years.
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As part of her multistep skin care routine before bed, Ms. Panton does facial cupping, for better circulation, and ends with the facial-massage technique gua sha, pushing a hard, curved tool around the contours of her face for lymphatic drainage.
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Previously, importing photos to Lightroom was a multistep process that required users to import photos to their iPad camera roll first, transferring it to Lightroom, and then deleting them from the camera roll to free up space on their iPads.
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"I think it's going to bring more people in," said Kai Libby, 55, a retired Border Patrol agent who became the town's first assessor last year to help shepherd the deorganization effort through the multistep process (and thus eliminate his own position).
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However, they said that the risk of infection is "extremely low," as the tools were almost fully sterilized — "during this time, one step in a multistep cleaning process was not completed with certain surgical instruments in a limited number of cases," the letter reads.
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"By combining the intuitiveness of learning from demonstration with the precision of motion-planning algorithms, this approach can help robots do new types of tasks that they haven't been able to learn before, like multistep assembly using both of their arms," noted Pérez-D'Arpino in MIT News.
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When a woman takes any of Sema4's tests she is walked through a multistep consent process that make it clear how the company would like to use the genetic information from both her and her unborn child for research and provides opportunities for opting out.
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The students outlined their thoughts using a multistep design process that could have been lifted straight from a start-up's business plan: blue-sky thinking (thinking outside the box), scope (the work and resources required to get something done), MVP (minimum viable product), delivery and launch.
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Mr. House has been hearing from angry voters from across the state and country who say they think the will of the people was ignored because Colorado's system of caucuses, a multistep process that ended on Saturday, left the selection of the state's presidential nominating delegates to party activists.
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We had practiced the multistep process of creating topographic models at Clark, but Sicily was our first time using the technique for the O.S.S. We had spent weeks covering sheets of cardboard with maps of the island's terrain — flowing lines marking the land area at each progressive altitude above sea level.
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Tom Price, the secretary of health and human services, suggested the report offered an incomplete picture because it did not take into account regulatory steps he intends to take, as well as other legislation that Republicans plan as part of their multistep strategy to repeal and replace the health law.
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The changes are sweeping, and they come as part of a multistep effort from Facebook these past two weeks to repair its image with politicians and the public, assuage critics condemning the company's privacy track record, and crack down on the misuse of its platform by third-party companies and foreign governments.
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I've tried just about every new solution that comes my way; "hair dusting" — a pro trick to remove fried ends — and a multistep technique my colorist performs that allows me to take my brown hair to an incredibly light place without going full-on platinum are just two of the most recent.
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Decades of experience treating young people from inner-city communities ravaged by drugs has shown us that recovery is a multistep, time-consuming process that, for the fortunate ones who are helped quickly enough, starts with overdose-prevention injections and detox, and continues with medically assisted treatment, behavior therapy and continuing community-based support.
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After six and a half months of traveling through space, InSight hit the top of Mars' atmosphere a little before 3PM ET. It then made a daring descent to the surface, performing a complex multistep routine that slowed the lander from more than 12,000 miles per hour to just 5 miles per hour before it hit the ground.
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"By demonstrating the multistep synthesis of baclofen in this integrated, benchtop device, the door has been opened to making complex molecules, such as APIs, on demand in nontraditional manufacturing environments such as hospitals or even doctors' offices, bringing manufacturing closer to the point of use," writes Christian Hornung, an Australian chemical engineering researcher, in a separate Science commentary.
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Chlorpyrifos is produced via a multistep synthesis from 3-Methylpyridine, eventually reacting 3,5,6-trichloro-2-pyridinol with diethylthiophosphoryl chloride.
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For numerical simulation of solution of the above equations, Kai Diethelm has suggested fractional linear multistep Adams–Bashforth method or quadrature methods.
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This multi-value (multistep) mutation at STR marker DYS464a to the value of 9 is found so far only in Swiss and German men.
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This multi-value (multistep) mutation at STR marker DYS391 to the value of 7 from the original 10 is found in a group of Hispanic men.
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S. Jezierski, L. Gitlin, S. Nagl, D. Belder, Multistep liquid-phase lithography for fast prototyping of microfluidic free-flow-electrophoresis chips, Anal. Bioanal. Chem., 2011, 401, 2651-2656.
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MupH is a Hydroxymethylglutaryl-Coenzyme A synthase, MupJ and MupK are Enoyl-CoA hydratases. Figure 4. The pyran ring of mupirocin is generated in this proposed multistep reaction.
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The definition of the global truncation error is also unchanged. The relation between local and global truncation errors is slightly different from in the simpler setting of one-step methods. For linear multistep methods, an additional concept called zero-stability is needed to explain the relation between local and global truncation errors. Linear multistep methods that satisfy the condition of zero-stability have the same relation between local and global errors as one-step methods.
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Carbomethoxymethylenetriphenylphosphorane can be made via a multistep reaction using bromoacetic acid, dicyclohexylcarbodiimide, and triphenylphosphine. This make a phosphonium salt, which is converted to the final product by sodium carbonate in water.
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In order to reach gram amounts in the multistep synthesis of this low solubility ring-closed carbazole (FICZ) the final purification by column chromatography was replaced by a crystallization step instead.
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PPO in avocados causes rapid browning upon exposure to oxygen, a multistep process involving oxidation reactions of both monophenols and polyphenols, resulting in o-quinone products subsequently converted irreversibly into brown polymeric pigments (melanins).
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In a multistep reaction, the rate-determining step does not necessarily correspond to the highest Gibbs energy on the reaction coordinate diagram.Keith J. Laidler. Chemical Kinetics (3rd ed., Harper and Row 1987) p. 283–285. .
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Isoleucine can be synthesized in a multistep procedure starting from 2-bromobutane and diethylmalonate. Synthetic isoleucine was originally reported in 1905 by French chemist Louis Bouveault. German chemist Felix Ehrlich discovered isoleucine in hemoglobin in 1903.
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Bicyclo[6.2.0]decapentaene can be synthesised in a multistep process from bicyclo[4.2.0]octa-3,7-diene-2,5- dione. This is irradiated with ultraviolet producing a tricyclo decadiendione. This is then reduced to a diol with lithium aluminium hydride.
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The stability region of the higher-order BDF methods contain a large part of the left half-plane and in particular the whole of the negative real axis. The BDF methods are the most efficient linear multistep methods of this kind.
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Santonic acid is an organic compound containing both carboxylic acid and ketone functionality. It was synthesized from santonin by base-mediated hydrolysis of a lactone followed by a multistep rearrangement process by R. B. Woodward.Reusch, William (1999). "Base-catalyzed rearrangements ".
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It is prepared from pentaerythritol via a multistep procedure, beginning with the partial chlorination. The compound reacts with diiron nonacarbonyl to give the complex of trimethylenemethane Fe(η4-C(CH2)3)(CO)3. It is also a precursor to [1.1.1]-propellane.
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Researchers in the Netherlands have succeeded in building nanoreactors that can perform one-pot multistep reactions - the next step towards artificial cell-like devices in addition for applications involving the screening and diagnosis of a disease or illness.Another nanotechnology example of mimicking nature: nanoreactors for one-pot multistep reactions at NanoWerk A biochemical nanoreactor is created simply by unwrapping a biological virus through scientific methods, eliminating its harmful contents, and re-assembling its protein coat around a single molecule of enzyme.Viral nanoreactor captures single molecules at RSC.org The kinetic isotope effect is trapped in a single molecule within a membrane-based nanoreactor.
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For example, there is a limit to how well paper devices can control the rate and direction of flow of the sample. This introduces limitations regarding the handling of complex chemical compounds or managing multistep assays, depending on the biosensor in question.
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Hydroxylation has also been reported using solvent-free NaOH / hydrogen peroxide. C60(OH)8 was prepared using a multistep procedure starting from a mixed peroxide fullerene. The maximum number of hydroxyl groups that can be attached (hydrogen peroxide method) stands at 36–40.
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The algorithm can be applied wherever we can train a model as we receive data using Baum-WelchZhang, Yanxue, Dongmei Zhao, and Jinxing Liu. "The Application of Baum-Welch Algorithm in Multistep Attack." The Scientific World Journal 2014. or any general EM algorithm.
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For certain nucleophiles, solvolysis reaction are classified. Solvolysis involving water is called hydrolysis. Related terms are alcoholysis (alcohols) and specifically methanolysis (methanol), acetolysis, ammonolysis (ammonia), and aminolysis (alkyl amines). Glycolysis is however an older term for the multistep conversion of glucose to pyruvate.
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Several synthetic routes exist to corannulene. Flash vacuum pyrolysis techniques generally have lower chemical yields than solution- chemistry syntheses, but offer routes to more derivatives. Corannulane was first isolated in 1966 by multistep organic synthesis. In 1971, the synthesis and properties of corannulane were reported.
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The parent triptycene was first prepared in 1942 by a multistep method. It can also be prepared in one step in 28% yield from the Diels–Alder reaction of anthracene and benzyne. In this method, benzyne is generated by the reaction of magnesium and 2-bromofluorobenzene.
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Functional DNA walkers: Additionally, a linear walker has been demonstrated that performs DNA- templated synthesis as the walker advances along the track, allowing autonomous multistep chemical synthesis directed by the walker.Functional DNA walkers: The synthetic DNA walkers' function is similar to that of the proteins dynein and kinesin.
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One important application are the many macrocyclic antibiotics, the macrolides, e.g. clarithromycin. Many metallocofactors are bound to macrocyclic ligands, which include porphyrins, corrins, and chlorins. These rings arise from multistep biosynthetic processes that also feature macrocycles. Macrocycles often bind ions and facilitate ion transport across hydrophobic membranes and solvents.
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She has served as a visiting professor at Moscow State University (1992), Beijing Institute of Technology (2004), and University of Xi'an (2004). She was awarded a fellowship at the Japan Society for the Promotion of Science in 2012. Her research focuses on palladium as a catalyst for multistep organic reactions.
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In numerical analysis and scientific computing, the trapezoidal rule is a numerical method to solve ordinary differential equations derived from the trapezoidal rule for computing integrals. The trapezoidal rule is an implicit second-order method, which can be considered as both a Runge–Kutta method and a linear multistep method.
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The catalytic mechanism of FGE is well studied. A multistep redox reaction with a covalent enzyme:substrate intermediate is proposed. The role of the cysteine residue for the occurring conversion was studied by mutating the cysteine to alanine. No conversion was found using mass spectrometry when the mutated peptide tag was used.
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DNA‐templated organic synthesis (DTS) is a way to control the reactivity of synthetic molecules by using nature's molarity‐based approach. Historically, DTS was used as a model of prebiotic nucleic acid replication. Now however, it is capable of translating DNA sequences into complex small‐molecule and polymer products of multistep organic synthesis.
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Madder was also used to dye the "hunting pinks" of Great Britain. Turkey red was a strong, very fast red dye for cotton obtained from madder root via a complicated multistep process involving "sumac and oak galls, calf's blood, sheep's dung, oil, soda, alum, and a solution of tin".Goodwin (1982), p. 65.
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Acetal protection of a ketone with ethylene glycol during reduction of an ester, vs. reduction to a diol when unprotected. A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis.
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The kinetic order of any elementary reaction or reaction step is equal to its molecularity, and the rate equation of an elementary reaction can therefore be determined by inspection, from the molecularity. The kinetic order of a complex (multistep) reaction, however, cannot be equated to molecularity since molecularity only describes elementary reactions or steps.
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Metastasis of Paget cells from the epidermis to distant regions is a multistep process that involves: # Invasion of local lymph nodes and venous system # Movement out from lymph nodes and venous system # Proliferation at new site Protein molecules HER2 and mTOR expressed in Paget cells are responsible for providing characteristics of proliferation and survival.
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Then it is solved by multistep methods such as the Euler method, midpoint method or Gragg's modified Midpoint method. These all require solution of a large system of linear equations; accomplished by sparse matrix techniques. Richardson extrapolation is used to improve accuracy. The final result is an accurate solution of the original non-linear equations.
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Dynamic programming is an approach to optimization that restates a multiperiod or multistep optimization problem in recursive form. The key result in dynamic programming is the Bellman equation, which writes the value of the optimization problem at an earlier time (or earlier step) in terms of its value at a later time (or later step).
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SPR imaging is used to study the multiple adsorption interactions in an array format under same experimental conditions. Nelson and his coworkers introduced a multistep procedure to create DNA arrays on gold surfaces for use with SPR imaging. Affinity interactions can be studied for a variety of target molecules e.g. proteins and nucleic acids.
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Urist made the key discovery that demineralized, lyophilized segments of bone induced new bone formation when implanted in muscle pouches in rabbits. This discovery was published in 1965 by Urist in Science. Urist proposed the name "Bone Morphogenetic Protein" in the scientific literature in the Journal of Dental Research in 1971. Bone induction is a sequential multistep cascade.
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The electron or arrow pushing method is often used in illustrating a reaction mechanism; for example, see the illustration of the mechanism for benzoin condensation in the following examples section. A reaction mechanism must also account for the order in which molecules react. Often what appears to be a single-step conversion is in fact a multistep reaction.
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Piperonal can be prepared by oxidizing isosafrole or by using a multistep sequence from catechol or 1,2-methylenedioxybenzene. Synthesis from the latter chemical is accomplished through a condensation reaction with glyoxylic acid followed by cleaving the resulting α-hydroxy acid with an oxidizing agent. Synthesis from catechol requires an additional step, Williamson ether synthesis using dichloromethane.
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Jensen's research revolves around reaction and separation techniques for on- demand multistep synthesis, methods for automated synthesis, and microsystems biological discovery and manipulation. He is considered one of the pioneers of flow chemistry. Jensen, Armon Sharei and Robert S. Langer were the founders of SQZ Biotech. The trio, together with Andrea Adamo, developed the cell squeezing method in 2012.
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Professor Reddi discovered that bone induction is a sequential multistep cascade involving chemotaxis, mitosis, and differentiation. Early studies in his laboratory at the University of Chicago and National Institutes of Health unraveled the sequence of events involved in bone matrix-induce bone morphogenesis.Reddi, A. H.; Huggins, C. (1972). "Biochemical Sequences in the Transformation of Normal Fibroblasts in Adolescent Rat".
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This causes cryptic translocation and therefore deletes the putative tumor suppressor gene CDKN2A (INK4A). At the same time, TLX1 and NOTCH1 may also be activated at higher frequency than usual. The multistep prognosis of T-ALL has hence been said to intensify and rapidly progress due to accumulation of effects resulting from dysregulation of multiple signaling pathways.
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Aromatic sulfonic acids are intermediates in the preparation of dyes and many pharmaceuticals. Sulfonation of anilines lead to a large group of sulfa drugs. Allura Red AC, a food coloring agent, is made by a multistep process that includes two sulfonations. Sulfonation of polystyrene is used to make sodium polystyrene sulfonate, a common ion exchange resin for water softening.
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It can be produced in a multistep process from phenol, which is converted to its 4-sulfonic acid derivative. The resulting phenol sulfonic acid chlorinates at the positions flanking the phenol. Hydrolysis releases the sulfonic acid group. An alternative synthesis starts with the ethyl ester of 4-hydroxybenzoic acid, which chlorinates at the positions flanking the phenolic center.
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Racemic tartaric acid (i.e.: a 50:50 mixture of D-(−)-tartaric acid and L-(+)-tartaric acid molecules, racemic acid) can be prepared in a multistep reaction from maleic acid. In the first step, the maleic acid is epoxidized by hydrogen peroxide using potassium tungstate as a catalyst. :HO2CC2H2CO2H + H2O2 → OC2H2(CO2H) 2 In the next step, the epoxide is hydrolyzed.
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Atomic commits in database systems fulfil two of the key properties of ACID, atomicity and consistency. Consistency is only achieved if each change in the atomic commit is consistent. As shown in the example atomic commits are critical to multistep operations in databases. Due to modern hardware design of the physical disk on which the database resides true atomic commits cannot exist.
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Multigrid methods have also been adopted for the solution of initial value problems. Of particular interest here are parallel-in-time multigrid methods: in contrast to classical Runge–Kutta or linear multistep methods, they can offer concurrency in temporal direction. The well known Parareal parallel-in-time integration method can also be reformulated as a two-level multigrid in time.
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The ability to invade surrounding tissue and metastasise is a hallmark of cancer. The hallmarks of cancer comprise six biological capabilities acquired during the multistep development of human tumors. The hallmarks constitute an organizing principle for rationalizing the complexities of neoplastic disease. They include sustaining proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis.
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Numerov's method (also called Cowell's method) is a numerical method to solve ordinary differential equations of second order in which the first-order term does not appear. It is a fourth-order linear multistep method. The method is implicit, but can be made explicit if the differential equation is linear. Numerov's method was developed by the Russian astronomer Boris Vasil'evich Numerov.
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Multistep tandem reactions (or cascade reactions) are a sequence of chemical transformations (usually more than two steps) that happens consecutively to convert a starting material to a complex product.Nicolaou, K. C.; Edmonds, David J.; Bulger, Paul G. Angew. Chem. Int. Ed. 2006, 45, 7134-7186. This kind of organic reactions are designed to construct difficult structures encountered in natural product total synthesis.
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Histidine phosphotransfer proteins transfer the phosphate in the multistep phosphorelay signaling pathway from cytokinin sensor kinases to their final target, cytokinin response regulators. In Arabidopsis thaliana, most histidine phosphotransfer proteins are redundant, positive regulators in cytokinin signaling. Most of the Arabidopsis thaliana histidine phosphotransfer proteins have functional overlap and affect many aspects of plant development. AHP4, however, might play a negative role in cytokinin responses.
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Bacterial cell growth necessitates synthesis of peptidoglycan. Assembly of peptidoglycan is a multistep process starting in the cytoplasm and ending in the exterior cell surface. The intracellular part of the pathway results in the production of the membrane-anchored cell wall precursor, Lipid II. After synthesis, this lipid intermediate is translocated across the cell membrane. The translocation (flipping) step of Lipid II requires a specific protein (flippase).
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This guarantees that no short- circuiting of an input line-to-line voltage can occur. Additionally a current path must be continuously provided. Therefore multistep commutation schemes, using voltage independent and current independent commutation as known for the Conventional Direct Matrix Converter P. Wheeler, J. Rodriguez, J. Clare, L. Empringham, A. Weinstein, “Matrix converters: A technology review”, IEEE Transactions on Industrial Electronics, Vol. 49, No. 2, pp.
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Staple nonwovens are made in 4 steps. Fibers are first spun, cut to a few centimeters length, and put into bales. The staple fibers are then blended, "opened" in a multistep process, dispersed on a conveyor belt, and spread in a uniform web by a wetlaid, airlaid, or carding/crosslapping process. Wetlaid operations typically use long fibers, but sometimes longer if the fiber is stiff or thick.
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This was in the late 1970s, when HIV was yet unknown to medicine. In addition to the sought-after hepatitis B surface proteins, the blood samples likely contained HIV. Hilleman devised a multistep process to purify this blood so that only the hepatitis B surface proteins remained. Every known virus was killed by this process, and Hilleman was confident that the vaccine was safe.
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Mediator of RNA polymerase II transcription subunit 26 is an enzyme that in humans is encoded by the MED26 gene. It forms part of the Mediator complex. The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus.
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TAP-mediated peptide transport is a multistep process. The peptide-binding pocket is formed by TAP-1 and TAP-2. Association with TAP is an ATP-independent event, ‘in a fast bimolecular association step, peptide binds to TAP, followed by a slow isomerisation of the TAP complex’. It is suggested that the conformational change in structure triggers ATP hydrolysis and so initiates peptide transport.
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Fixation is usually the first stage in a multistep process to prepare a sample of biological material for microscopy or other analysis. Therefore, the choice of fixative and fixation protocol may depend on the additional processing steps and final analyses that are planned. For example, immunohistochemistry uses antibodies that bind to a specific protein target. Prolonged fixation can chemically mask these targets and prevent antibody binding.
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Dehydrosecodine is a terpene indole alkaloid. The compound is believed to be an unstable O-acetylated secodine type intermediate in the formation of catharanthine and tabersonine from stemmadenine.Qu, Y., Easson, M. E., Simionescu, R., Hajicek, J., Thamm, A. M., Salim, V., & De Luca, V. (2018). Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine.
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The stability of numerical methods for solving stiff equations is indicated by their region of absolute stability. For the BDF methods, these regions are shown in the plots below. Ideally, the region contains the left half of the complex plane, in which case the method is said to be A-stable. However, linear multistep methods with an order greater than 2 cannot be A-stable.
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The initiation of the transcription is a multistep sequential process that involves several mechanisms: promoter location, initial reversible binding of RNA polymerase, conformational changes in RNA polymerase, conformational changes in DNA, binding of nucleoside triphosphate (NTP) to the functional RNA polymerase-promoter complex, and nonproductive and productive initiation of RNA synthesis. The promoter binding process is crucial in the understanding of the process of gene expression.
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In his 2016 Handbook of Synthetic Organic Chemistry, Michael Pirrung wrote that yield is one of the primary factors synthetic chemists must consider in evaluating a synthetic method or a particular transformation in "multistep syntheses." He wrote that a yield based on recovered starting material (BRSM) or (BORSM) does not provide the theoretical yield or the "100% of the amount of product calculated", that is necessary in order to take the next step in the multistep systhesis. Purification steps always lower the yield, through losses incurred during the transfer of material between reaction vessels and purification apparatus or imperfect separation of the product from impurities, which may necessitate the discarding of fractions deemed insufficiently pure. The yield of the product measured after purification (typically to >95% spectroscopic purity, or to sufficient purity to pass combustion analysis) is called the isolated yield of the reaction.
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Collagen VI (ColVI) is a type of collagen primarily associated with the extracellular matrix of skeletal muscle. ColVI maintains regularity in muscle function and stabilizes the cell membrane. It is synthesized by a complex, multistep pathway that leads to the formation of a unique network of linked microfilaments located in the extracellular matrix (ECM). ColVI plays a vital role in numerous cell types, including chondrocytes, neurons, myocytes, fibroblasts, and cardiomyocytes.
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Triethylaluminium can be formed via several routes. The discovery of an efficient route was a significant technological achievement. The multistep process uses aluminium metal, hydrogen gas, and ethylene, summarized as follows: :2 Al + 3 H2 \+ 6 C2H4 → Al2Et6 Because of this efficient synthesis, triethylaluminium is one of the most available organoaluminium compounds. Triethylaluminium can also be generated from ethylaluminium sesquichloride (Al2Cl3Et3), which arises by treating aluminium powder with chloroethane.
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Na(silox) is usually prepared by deprotonation of the silanol (t-Bu)3SiOH, which is prepared by a multistep route via the intermediacy of (t-Bu)2SiF2.Edward M. Dexheimer and Leornard Spialter, Lee D. Smithson "Tri-t-butylsilane: synthesis, physical properties, derivatives, and reactivity towards ozonolysis, chlorination, fluorination, and hydrolysis" Journal of Organometallic Chemistry 102, 1975, 21-27.. It is also obtained by treatment of tBu3SiNa with nitrous oxide.
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During the research revealed information about the psychological and social processes that influence voting decisions. The study also uncovered an influence process that Lazarsfeld called "opinion leadership." He concluded that there is a multistep flow of information from the mass media to persons who serve as opinion leaders which then is passed on to the general public. He called this communication process the "two-step flow of communication".
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Effectively, this results in a higher concentration of drug to be in contact with the tumor for a longer period of time. Park et al. conceptualized carcinogenesis of hepatocellular carcinoma (HCC) as a multistep process involving parenchymal arterialization, sinusoidal capillarization, and development of unpaired arteries (a vital component of tumor angiogenesis). All these events lead to a gradual shift in tumor blood supply from portal to arterial circulation.
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Acta hydrochimica et hydrobiologica, 26(3), 152-157. In biofilms, nanowires and multistep electron hopping (in which electrons jump from cell to cell towards the mineral) have also been suggested as methods for reducing metals without requiring direct cell contact. It has been proposed that cytochromes c are involved in both of these mechanisms. In nanowires, for instance, cytochromes c function as the final component that transfers electrons to the metal oxide.
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Fig 4: Multistep commutation of the Sparse Matrix Converter rectifier input stage. This is a commutation scheme, depicted in Fig. 4. For a given switching state of the rectifier input stage, the commutation of the inverter output stage has to be performed in an identical manner to the commutation of a conventional voltage dc-link converter. The basic structure of the commutating bridge legs of the Sparse Matrix Converter is shown in Fig. 4(a).
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The use of the amino acid glutamine as an energy source is facilitated by the multistep catabolism of glutamine called glutaminolysis. This energy pathway is upregulated in cancer, which may represent a therapeutic target as cancer cells are thought to be more dependent on glutamine than healthy cells. This especially holds true for specific tumor types that are metabolically dysregulated, such as malignant brain tumors (i.e. glioblastoma) that carry mutations in the IDH1 gene.
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In the cave, situated near Rignano Garganico, there are more than 45,000 individual finds, including Paleolithic tools, human and animal bones. They are currently housed in Rignano Garganico's Museum. Evidence of paleolithic oat harvesting dating to 30,600 BC was linked to a pestle recovered from the cave. Multistep food plant processing at Grotta Paglicci (Southern Italy) around 32,600 cal B.P. The cave contains also some Paleolithic mural paintings, depicting horses and handprints.
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Hammond's postulate is especially important when looking at the rate-limiting step of a reaction. However, one must be cautious when examining a multistep reaction or one with the possibility of rearrangements during an intermediate stage. In some cases, the final products appear in skewed ratios in favor of a more unstable product (called the kinetic product) rather than the more stable product (the thermodynamic product). In this case one must examine the rate-limiting step and the intermediates.
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51, 574-579 (2006). Recently a multistep nucleic acid extraction procedure was introduced to provide DNA lysates of highest quality.Nature Methods “Differential lysis in a single-tube extraction process for accurate forensic profiling”, 8 May 2012 A self-sealing membrane allows a stepwise release and separation of DNA from mixed specimens. Implemented in a spin-column system, it is ideally suitable for DNA extraction procedures involving differential extraction of forensic samples such as epithelium, saliva or blood vs. sperms.
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Hammond's postulate is especially important when looking at the rate-limiting step of a reaction. However, one must be cautious when examining a multistep reaction or one with the possibility of rearrangements during an intermediate stage. In some cases, the final products appear in skewed ratios in favor of a more unstable product (called the kinetic product) rather than the more stable product (the thermodynamic product). In this case one must examine the rate- limiting step and the intermediates.
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The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1. This protein is also a component of other multisubunit complexes e.g.
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Many metal forming operation require too much deformation of the blank to be performed in a single step. Multistep or progressive stamping operations are used to incrementally form the blank into the desired shape through a series of stamping operations. Incremental forming simulation software platforms addresses these operations with a series of one-step stamping operations that simulate the forming process one step at a time.Tim Stephens, “Incremental Forming Simulation Software,” Metal Forming Magazine, June 2013.
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The backward differentiation formula (BDF) is a family of implicit methods for the numerical integration of ordinary differential equations. They are linear multistep methods that, for a given function and time, approximate the derivative of that function using information from already computed time points, thereby increasing the accuracy of the approximation. These methods are especially used for the solution of stiff differential equations. The methods were first introduced by Charles F. Curtiss and Joseph O. Hirschfelder in 1952.
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The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co- activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1. This protein is also a component of other multisubunit complexes e.g.
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This reaction was studied by Farrington Daniels and coworkers, and initially assumed to be a true unimolecular reaction. However it is now known to be a multistep reaction whose mechanism was established by Ogg as: :N2O5 NO2 \+ NO3 :NO2 \+ NO3 -> NO2 \+ O2 \+ NO :NO + N2O5 -> 3 NO2 An analysis using the steady-state approximation shows that this mechanism can also explain the observed first-order kinetics and the fall-off of the rate constant at very low pressures.
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The presence of Mycoplasma was first reported in samples of cancer tissue in the 1960s. Since then, several studies tried to find and prove the connection between Mycoplasma and cancer, as well as how the bacterium might be involved in the formation of cancer. Several studies have shown that cells that are chronically infected with the bacteria go through a multistep transformation. The changes caused by chronic mycoplasmal infections occur gradually and are both morphological and genetic.
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Santonin can be converted to santonic acid (C15H20O4) via based-catalyzed hydrolysis followed by a multistep rearrangement process.Base-catalyzed rearrangements Santonin dissolves in alkalies with formation of salts of this carboxylic acid. Santonin, in acetic acid solution, when exposed to sunlight for about a month, is converted into (colorless) photosantonic acid (C15H22O5) which is generally regarded as less toxic. The ethyl ester of the latter is obtained when an alcoholic solution of santonin is exposed to sunlight (Sestini).
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In the total synthesis of spiroketal ionophore antibiotic routiennocin 1 (Fig. 1), the central spiroketal skeleton was constructed by a multistep tandem reaction (Fig. 2).Diez-Martin, D. Kotecha, N. R.; Ley, S. V.; Mantegani, S.; Menendez, J. C.; Organ, H. M.; White, A. D., Tetrahedron, 1992, 48, 1899-7938. Fragment A and fragment B were coupled in a single step to form the key intermediate G that could be further elaborated to afford the final product routiennocin. Fig.
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In the usual aldol addition, a carbonyl compound is deprotonated to form the enolate. The enolate is added to an aldehyde or ketone, which forms an alkoxide, which is then protonated on workup. A superior method, in principle, would avoid the requirement for a multistep sequence in favor of a "direct" reaction that could be done in a single process step. One idea is to generate the enolate using a metal catalyst that is released after the aldol addition mechanism.
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Multistep-feedback loop mechanism also leads to ultrasensitivity. There is paper introducing that engineering synthetic feedback loops using yeast mating mitogen-activated protein (MAP) kinase pathway as a model system. In Yeast mating pathway: alpha-factor activates receptor, Ste2, and Ste4 and activated Ste4 recruits Ste5 complex to membrane, allowing PAK-like kinase Ste20 (membrane-localized) to activate MAPKKK Ste11. Ste11 and downstream kinases, Ste7 (MAPKK) and Fus3 (MAPK), are colocalized on the scaffold and activation of cascade leads to transcriptional program.
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The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The mediator of RNA polymerase II transcription subunit 1 protein is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1. This protein is also a component of other multisubunit complexes [e.g.
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Researchers are exploring the creation of 'smart' organisms such as bacteriophages and bacteria that can perform complex immunological tasks. Such strategies could produce organisms that perform multistep immune functions such as presenting antigen to and co-stimulating helper T cells in a specific manner, or providing integrated signals to B cells to induce affinity maturation and isotype switching during antibody production. Such engineered organisms have the potential be as safe and as inexpensive as probiotics but precise in carrying out targeted interventions.
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For some differential equations, application of standard methods—such as the Euler method, explicit Runge–Kutta methods, or multistep methods (for example, Adams–Bashforth methods)—exhibit instability in the solutions, though other methods may produce stable solutions. This "difficult behaviour" in the equation (which may not necessarily be complex itself) is described as stiffness, and is often caused by the presence of different time scales in the underlying problem.Miranker, A. (2001). Numerical Methods for Stiff Equations and Singular Perturbation Problems: and singular perturbation problems (Vol. 5).
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In general, on the typical laboratory scale, the direct reaction of a haloalkane with sodium hydrosulfide is inefficient owing to the competing formation of sulfides. Instead, alkyl halides are converted to thiols via an S-alkylation of thiourea. This multistep, one-pot process proceeds via the intermediacy of the isothiouronium salt, which is hydrolyzed in a separate step:. : CH3CH2Br + SC(NH2)2 → [CH3CH2SC(NH2)2]Br : [CH3CH2SC(NH2)2]Br + NaOH → CH3CH2SH + OC(NH2)2 \+ NaBr The thiourea route works well with primary halides, especially activated ones.
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Expansion microscopy is a multistep process that, depending on the protocol, has different requirements for gelation and expansion. The sequence of steps are stain, link, digest, and expand The staining process can take many different forms, and only requires that the fluorophores used can attach to the polymer in the next step. Linking is the process of adding a polymer gel to the cells, which permeabilize through the cell. The linking step also includes, as the name suggests, the process of linking the fluorophores to the gel.
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Mediator of RNA polymerase II transcription subunit 7 is an enzyme that in humans is encoded by the MED7 gene. The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1.
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3D printing has found its place in soft sensors and actuators manufacturing inspired by 4D printing concept.< The majority of the conventional soft sensors and actuators are fabricated using multistep low yield processes entailing manual fabrication, post- processing/assembly, and lengthy iterations with less flexibility in customization and reproducibility of final products. 3D printing has been a game changer in these fields with introducing the custom geometrical, functional, and control properties to avoid the tedious and time-consuming aspects of the earlier fabrication processes.
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Fig 5: Zero DC link current commutation shown for the Sparse Matrix Converter. The drawback of the multistep commutation describe before is its complexity. Indirect matrix converters like the Sparse Matrix Converter provide a degree of control freedom that is not available for the Conventional Direct Matrix Converter. This can be used to simplify the complex commutation problem. It has been proposed J. Holtz, U. Boelkens, “Direct frequency converter with sinusoidal line currents for speed-variable ac motors”, IEEE Transactions on Industrial Electronics, Vol.
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Before the crude materials (e.g. municipal or commercial waste) are introduced into the incineration unit, these resources are mechanically treated at an external station. The treatment intensity is significantly linked to the quality and composition of the primary material. So the treatment process can be very different – from an ordinary crushing and a rough sortation to a multistep milling process with various product streams and a finishing briquetting. The final product of this step – the Refuse derived fuel – is used in the “RDF- Powerstation”.
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The compound has been prepared in a multistep process starting with the base hydrolysis of phosphorus pentasulfide:R. Klement "Phosphorus" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 571-2. :P2S5 \+ 6 NaOH → 2 Na3PO2S2 \+ H2S + 2 H2O The salt is isolated as the hydrate Na3PO2S2.(H2O)11. It is prone to hydrolysis, especially when it is heated as an aqueous solutions: :Na3PO2S2 \+ 2 H2O → Na3PO3S + H2S Its structure has been examined by X-ray crystallography.
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Mediator of RNA polymerase II transcription subunit 17 is an enzyme that in humans is encoded by the MED17 gene. The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1.
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Trimethylaniline is a building block to a variety of bulky ligands. Condensation with glyoxal gives the 1,2-diimine ligands. An example is glyoxal-bis(mesitylimine), a yellow solid that is synthesized by condensation of 2,4,6-trimethylaniline and glyoxal. The diimine is a useful precursor to popular NHC ligands including IMes.Elon A. Ison, Ana Ison "Synthesis of Well-Defined Copper N-Heterocyclic Carbene Complexes and Their Use as Catalysts for a “Click Reaction”: A Multistep Experiment That Emphasizes the Role of Catalysis in Green Chemistry" J. Chem. Educ.
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In July 2015, the board of regents announced their intention to name the medical school after the late WSU president Elson Floyd; the name was officially changed to the Elson S. Floyd College of Medicine that September. After a national search, Dr. John Tomkowiak was selected as dean. In February 2016, the Liaison Committee on Medical Education granted the school candidate status, the first in a multistep process toward accreditation. In October 2016, Washington State University announced that the LCME had granted preliminary accreditation to the school.
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In most cases, when two cells collide they attempt to move in a different direction to avoid future collisions; this behavior is known as contact inhibition of locomotion. As the two cells come into contact, their locomotive process is paralyzed. This is accomplished via a multistep, multi- faceted mechanism that involves the formation of a cell-cell adhesion complex upon collision. The disassembly of this complex is thought to be driven largely by tension in the cells and ultimately results in the colliding cells' changing directions.
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Mediator of RNA polymerase II transcription subunit 14 is an enzyme that in humans is encoded by the MED14 gene. The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1.
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Synaptic vesicles dock and fuse in the active zone of the plasma membrane at chemical synapses. The presynaptic cytoskeletal matrix (PCM), which is associated with the active zone and is situated between synaptic vesicles, is thought to be involved in maintaining the neurotransmitter release site in register with the postsynaptic reception apparatus. The cycling of synaptic vesicles is a multistep process involving a number of proteins (see MIM 603215). Among the components of the PCM that orchestrate these events are Bassoon (BSN; MIM 604020), RIM (RIMS1; MIM 606629), Oboe (RIMS2; MIM 606630), and Piccolo (PCLO).
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The structure shows that the group I intron binds across the two subunits of the homodimeric protein with a newly evolved RNA-binding surface distinct from that which binds tRNA(Tyr). This RNA binding surface provides an extended scaffold for the phosphodiester backbone of the conserved catalytic core of the intron RNA, allowing the protein to promote the splicing of a wide variety of group I introns. The group I intron-binding surface includes three small insertions and additional structural adaptations relative to non- splicing eubacterial YARSs, indicating a multistep adaptation for splicing function.
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General linear methods (GLMs) are a large class of numerical methods used to obtain numerical solutions to differential equations. This large class of methods in numerical analysis encompass multistage Runge–Kutta methods that use intermediate collocation points, as well as linear multistep methods that save a finite time history of the solution. John C. Butcher originally coined this term for these methods, and has written a series of review papers a book chapter and a textbook on the topic. His collaborator, Zdzislaw Jackiewicz also has an extensive textbook on the topic.
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IUPAC Gold Book definition Many other terminologies are used for stepwise reactions: overall reaction, global reaction, apparent reaction, operational reaction, complex reaction, composite reaction, multiple step reaction, multistep reaction, etc. In contrast to elementary reactions which follow the law of mass action, the rate law of stepwise reactions is obtained by combining the rate laws of the multiple elementary steps, and can become rather complex. Moreover, when speaking about catalytic reactions, the diffusion may also limit the reaction. In general, however, there is one very slow step, which is the rate-determining step, i.e.
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Sucralose is manufactured by the selective chlorination of sucrose in a multistep synthesis, which substitutes three of the hydroxyl groups of sucrose with chlorine atoms. This chlorination is achieved by selective protection of a primary alcohol group, followed by chlorination of the partially acetylated sugar with excess chlorinating agent, and then by removal of the acetyl groups to give the desired sucralose product.Bert Fraser-Reid, 2012, "From Sugar to Splenda: A Personal and Scientific Journey of a Carbohydrate Chemist and Expert Witness," Berlin:Springer, pp. 199-210, and passim, see , accessed 2 November 2014.
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In addition to the narrowness of the actives site resulting from the enzyme's dimeric structure, this additional functionality is thought to be facilitated by two histidine residues (TAA His-122 and TAA His-296) that interact with the glycan bond to be cleaved. As these histidines are present in the other alpha-amylase enzymes it is thought the functional difference arises from a difference in transition state stabilization energy contributions from the side chains of adjacent residues which vary from enzyme to enzyme. This allows for neopullulanase's multistep breakdown of pullulan.
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Modern CISC implementations, such as the x86 family, decode instructions into dynamically buffered micro-operations ("μops") with an instruction encoding similar to RISC or traditional microcode. A hardwired instruction decode unit directly emits μops for common x86 instructions, but falls back to a more traditional microcode ROM for more complex or rarely used instructions. For example, an x86 might look up μops from microcode to handle complex multistep operations such as loop or string instructions, floating point unit transcendental functions or unusual values such as denormal numbers, and special purpose instructions such as CPUID.
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This function was discovered through the examination of mutants, whose nanowires could attach to the iron, but would not reduce it. However, Shewanella nanowires are not pili, but extensions of the outer membrane that contain the decaheme outer membrane cytochromes MtrC and OmcA. The reported presence of outer membrane cytochromes, and lack of conductivity in nanowires from the MtrC and OmcA- deficient mutant directly support the proposed multistep hopping mechanism for electron transport through Shewanella nanowires. Additionally, nanowires can facilitate long-range electron transfer across thick biofilm layers.
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In chemistry, a catalytic cycle is a multistep reaction mechanism that involves a catalyst.Kinetics of catalytic reactions 2005 M. Albert Vannice The catalytic cycle is the main method for describing the role of catalysts in biochemistry, organometallic chemistry, bioinorganic chemistry, materials science, etc. Since catalysts are regenerated, catalytic cycles are usually written as a sequence of chemical reactions in the form of a loop. In such loops, the initial step entails binding of one or more reactants by the catalyst, and the final step is the release of the product and regeneration of the catalyst.
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A particular RAFT agent is only suitable for a limited set of monomers and the synthesis of a RAFT agent typically requires a multistep synthetic procedure and subsequent purification. RAFT agents can be unstable over long time periods, are highly colored and can have a pungent odor due to gradual decomposition of the dithioester moiety to yield small sulfur compounds. The presence of sulfur and color in the resulting polymer may also be undesirable for some applications; however, this can, to an extent, be eliminated with further chemical and physical purification steps.
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The common method for the production of DMT from p-xylene (PX) and methanol consists of a multistep process involving both oxidation and esterification. A mixture of p-xylene (PX) and methyl p-toluate is oxidized with air in the presence of a cobalt and manganese catalysts. The acid mixture resulting from the oxidation is esterified with methanol to produce a mixture of esters. The crude ester mixture is distilled to remove all the heavy boilers and residue produced; the lighter esters are recycled to the oxidation section.
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The isotope 89Zr has been applied to the tracking and quantification of molecular antibodies with positron emission tomography (PET) cameras (a method called "immuno-PET"). Immuno-PET has reached a maturity of technical development and is now entering the phase of wide-scale clinical applications. Until recently, radiolabeling with 89Zr was a complicated procedure requiring multiple steps. In 2001–2003 an improved multistep procedure was developed using a succinylated derivative of desferrioxamine B (N-sucDf) as a bifunctional chelate, and a better way of binding 89Zr to mAbs was reported in 2009.
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Clopidol is an organic compound that is used as in veterinary medicine as a coccidiostat. It is prepared industrially by a multistep process from dehydroacetic acid. The US National Institute for Occupational Safety and Health has set a recommended exposure limit (REL) for clopidol at 10 mg/m3 TWA (time-weighted average) for total exposure, 5 mg/m3 TWA for respiratory exposure, and 20 mg/m3 for short-term exposure. The Occupational Safety and Health Administration has set a permissible exposure limit (PEL); the respiratory PEL is the same as the REL, but the total exposure limit is 15 mg/m3.
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This reaction product is very unstable with initial loss of carbon dioxide and followed by many secondary reactions. This is believed to be due to steric strain resulting from the methyl group and the carboxylic group in the cis-dienoid structure. Isoprenetricarboxylic acid Occasionally, an aldol condensation is buried in a multistep reaction or in catalytic cycle as in the following example: Ru Catalyzed Cyclization of Terminal Alkynals to Cycloalkenes In this reaction an alkynal 1 is converted into a cycloalkene 7 with a ruthenium catalyst and the actual condensation takes place with intermediate 3 through 5.
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The epidermis- type lipoxygenases are now regarded as a distinct subclass within the multigene family of mammalian lipoxygenases with mouse Aloxe3 (also termed e-Lox-3) being the ortholog to human ALOXE3, mouse Alox12b being the ortholog to human ALOX12B (MIM 603741), and mouse Alox8 being the ortholog to human ALOX15B (MIM 603697)[supplied by OMIM]. ALOX12B and ALOXE3 in humans, Alox12b and Aloxe3 in mice, and comparable orthologs in other in other species are proposed to act sequentially in a multistep metabolic pathway that forms products that are structurally critical for creating and maintaining the skin's water barrier function.
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The multistep reaction mechanism begins with deprotonation of the alcohol, followed by the oxygen-anion attacking the adjacent trichloromethyl position to form an epoxide. The azide then opens this ring by an SN2 reaction to give a 2-azido structure whose stereochemistry is inverted compared to the original 2-hydroxy. The oxygen, having become attached to the first carbon of the chain during the epoxide formation, simultaneously displaces a second chlorine atom there to form an acyl chloride. An additional nucleophilic reactant, such as hydroxide or an alkoxide, then triggers an acyl substitution there to produce a carboxylic acid or ester.
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The biosynthesis of macrophomic acid is catalyzed by the enzyme macrophomate synthase. The unusual multistep conversion of 5-acetyl-4-methoxy-6-methyl-2-pyrone (3) to macrophomic acid is thought to proceed by either a concerted Diels-Alder reaction or a recently proposed 2-step Michael-aldol sequence. The Michael- aldol sequence involves a Michael addition reaction and an aldol condensation. The actual pathway is not yet understood completely. In the conversion of the 2-pyrone (3), oxaloacetate (1) is decarboxylated to form an enolate that coordinates to a Mg2+ metal center (2) found in the active site of the enzyme.
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The exchange of GDP for GTP induces a conformational change of RAS to allow it to bind to Raf-1. Raf-1 is then activated through another multistep mechanism in which dephosphorylation of inhibitory sites by protein phosphatase 2A (PP2A), as well as the phosphorylation of activating sites by p21 activated kinase (PAK) occurs. After this, Raf-1 activates MAPK/ERK kinase (MEK), which then goes on to activate extracellular-signal-regulated kinase (ERK). ERK is then able to enter the cell nucleus and control gene expression by phosphorylating various transcription factors, such as Elk-1.
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The research base on children' mathematical thinking upon which CGI is based shows that children are able to solve problems without direct instruction by drawing upon informal knowledge of everyday situations. For example, a study of kindergarten childrenCarpenter, et al., 1993 showed that young children can solve problems involving what are normally considered advanced mathematics such as multiplication, division, and multistep problems, by using direct modeling. Direct modeling is an approach to problem solving in which the child, in the absence of more sophisticated knowledge of mathematics, constructs a solution to a story problem by modeling the action or structure.
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In March, the WHO initiated the "SOLIDARITY Trial" in 10 countries, enrolling thousands of people infected with COVID‑19 to assess treatment effects of four existing antiviral compounds with the most promise of efficacy. A dynamic, systematic review was established in April 2020 to track the progress of registered clinical trials for COVID‑19 vaccine and therapeutic drug candidates. Drug development is a multistep process, typically requiring more than five years to assure safety and efficacy of the new compound. Several national regulatory agencies, such as the EMA and the FDA, approved procedures to expedite clinical testing.
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Biochemical processes that use kinetic proofreading to improve specificity implement the delay-inducing multistep ratchet by a variety of distinct biochemical networks. Nonetheless, many such networks result in the times to completion of the molecular assembly and the proofreading steps (also known as the first passage time) that approach a near-universal, exponential shape for high proofreading rates and large network sizes. Since exponential completion times are characteristic of a two-state Markov process, this observation makes kinetic proofreading one of only a few examples of biochemical processes where structural complexity results in a much simpler large-scale, phenomenological dynamics.
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Glioblastoma multiforme is a form of malignant, grade IV tumor of the central nervous system. Most of diagnosed glioblastoma multiforme cases (around 90% are in fact primary gliomas) arise from normal glial cells by following a multistep oncogenesis process. The remaining of diagnosed glioblastomas are originated from lower grade tumors, and the expansion rate of these is distinctly slower than for primary gliomas. Glioblastoma has been linked to certain genetic alterations and deregulations, but it mostly occurs spontaneously and its progression is associated with deregulation of the G1/S checkpoints, as well as other genetic abnormalities commonly associated with tumor cells.
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99mTc is conveniently available in high radionuclidic purity from molybdenum-99, which decays with 87% probability to 99mTc. The subsequent decay of 99mTc leads to either 99Tc or 99Ru. 99Mo can be produced in a nuclear reactor via irradiation of either molybdenum-98 or naturally occurring molybdenum with thermal neutrons, but this is not the method currently in use today. Currently, 99Mo is recovered as a product of the nuclear fission reaction of 235U, separated from other fission products via a multistep process and loaded onto a column of alumina that forms the core of a 99Mo/99mTc radioisotope "generator".
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Impaired verbal comprehension can be the result a number of causes such as failure of speech sound discrimination, word recognition, auditory working memory, or syntactic structure building. When clinically examined, patients with TSA will exhibit poor comprehension of verbal commands. Based on the extent of the comprehension deficiency, patients will have difficulty following simple commands, e.g. “close your eyes.” Depending on the extent of affected brain area, patients are able to follow simple commands but may not be able to comprehend more difficult, multistep commands, e.g. “point to the ceiling, then touch your left ear with your right hand.
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If L is small as compared with Lmfp, which normally is the case for very small vias, the technological parameters to optimize are primarily the contact resistance and the tube density. Initial works have been focused on CNT vias connecting two metallic lines. Low temperature (400 °C) chemical vapor deposition growth of CNT on titanium nitride catalysed by cobalt particles has been optimized by the Fujitsu group. The catalyst particles obtained by laser ablation of a cobalt target sorted by size ultimately allow to grow a CNT density around 1012 CNT cm−2 using a multistep process using plasma and catalyst particles around 4 nm.
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By optimizing each step for the intended purpose and arranging them that minimizes inter step treatments, the number of steps will be minimized. A typical multistep purification protocol starts with a preliminary capture step which often utilizes ion exchange chromatography (IEC). The media (stationary phase) resin consists of beads, which range in size from being large (good for fast flow rates and little to no sample clarification at the expense of resolution) to small (for best possible resolution with all other factors being equal). Short and wide column geometries are amenable to high flow rates also at the expense of resolution, typically because of lateral diffusion of sample on the column.
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Many strategies exist in chemical synthesis that go beyond converting reactant A to reaction product B in a single step. In multistep synthesis, a chemical compound is synthesised though a series of individual chemical reactions, each with their own work-up.Advanced Organic Chemistry Part B: Reactions and Synthesis Francis A. Carey,Richard J. Sundberg Springer 2013 For example, a laboratory synthesis of paracetamol can consist of three individual synthetic steps. In cascade reactions multiple chemical transformations take place within a single reactant, in multi-component reactions up to 11 different reactants form a single reaction product and in a telescopic synthesis one reactant goes through multiple transformations without isolation of intermediates.
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The building block approach to drug discovery changed the landscape of chemical industry which supports medicinal chemistry. Major chemical suppliers for medicinal chemistry like Maybridge, Chembridge, Enamine adjusted their business correspondingly. By the end of the 1990th the use of building block collections prepared for fast and reliable construction of small-molecule sets of compounds (libraries) for biological screening became one of the major strategies for pharmaceutical industry involved in drug discovery; modular, usually one-step synthesis of compounds for biological screening from building blocks turned out to be in most cases faster and more reliable than multistep, even convergent syntheses of target compounds. There are online web-resources.
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It causes repetitive firing and prolongation of action potentials, particularly in the central nervous system of insects. The increase in signaling is what causes the intense pain from bullet ant stings. Poneratoxin is in an inactive state when stored in the ant venom reservoir due to the reservoir's acidic conditions, but it becomes toxic when activated via a multistep process. The combination of poneratoxin binding to a cell membrane (in order to act upon a voltage-gated sodium channel) and the movement from acidic conditions in the ant venom reservoir to basic conditions at the target site leads to poneratoxin undergoing a conformational change that activates it.
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These are consistent with experimental data, supporting an ordered, concerted transition state for the former and a multistep radical process for the latter. Several equivalent approaches, outlined below, lead to the same predictions. The aromatic transition state theory assumes that the minimum energy transition state for a pericyclic process is aromatic, with the choice of reaction topology determined by the number of electrons involved. For reactions involving (4n + 2)-electron systems (2, 6, 10, ... electrons; odd number of electron pairs), Hückel topology transition states are proposed, in which the reactive portion of the reacting molecule or molecules have orbitals interacting in a continuous cycle with an even number of nodes.
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More typical, however, is that a two-stage approach that will employ benefits and organizational psychographics and purchasing criteria will be needed to provide complete market profiles. Firmographics play crucial role in one of the most significant developments in business segmentation theory came in 1984 with the work of Bonoma and Shapiro who were the first to propose a truly multistep basis for segmenting business markets. They proposed the use of five general segmentation criteria which they arranged in a nested hierarchy. The set of segmentation bases captures from macro-level to micro-level, and firmographics belong to the macro approach and comprise from industry, company size, customer location.
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Fundamental (or rudimentary) numeracy skills include understanding of the real number line, time, measurement, and estimation. Fundamental skills include basic skills (the ability to identify and understand numbers) and computational skills (the ability to perform simple arithmetical operations and compare numerical magnitudes). More sophisticated numeracy skills include understanding of ratio concepts (notably fractions, proportions, percentages, and probabilities), and knowing when and how to perform multistep operations. Two categories of skills are included at the higher levels: the analytical skills (the ability to understand numerical information, such as required to interpret graphs and charts) and the statistical skills (the ability to apply higher probabilistic and statistical computation, such as conditional probabilities).
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Iodolactonization has been used in the synthesis of many biologically important products such as the tumor growth inhibitors vernolepin and vernomenin, the pancreatic lipase inhibitor vibralactone, and prostaglandins, a lipid found in animals. The following total syntheses all use iodolactonization as a key step in obtaining the desired product. In 1977, Samuel Danishefsky and coworkers were able to synthesize the tumor growth inhibitors dl-vernolepin and dl-vernomenin via a multistep process in which a lactonization was employed. This synthesis demonstrates the use of iodolactonization to preferentially form a five- membered ring over a four- or six-membered ring, as expected from Baldwin's Rules.
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In the Arrhenius equation, the term activation energy (Ea) is used to describe the energy required to reach the transition state, and the exponential relationship k = A exp(-Ea/RT) holds. In transition state theory, a more sophisticated model of the relationship between reaction rates and the transition state, a superficially similar mathematical relationship, the Eyring equation, is used to describe the rate of a reaction: k = (kBT / h) exp(–ΔG‡ / RT). However, instead of modeling the temperature dependence of reaction rate phenomenologically, the Eyring equation models individual elementary step of a reaction. Thus, for a multistep process, there is no straightforward relationship between the two models.
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Since the cylindrocyclophanes have such a unique structure and exciting biological possibilities due to their cytotoxicity, there have been numerous efforts to create them synthetically in the laboratory. One of the first attempts was the total synthesis of cylindrocyclophane F, which was accomplished in 20 steps with an 8.3% yield. This, along with other syntheses of cylindrocyclophanes, relies on multistep reaction mechanisms, typically employing Myers reductive coupling and Kowalski ester homologation to obtain the beginning resorcinol fragments and Danheiser benzannulation to construct the aromatic rings with multiple functional groups. After the first total synthesis of cylindrocyclophane F, total synthesis of cylindrocyclophanes A and F were accomplished using a new olefin metathesis dimerization cascade.
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The most common lymphomas are salivary extranodal marginal zone B cell lymphomas (MALT lymphomas in the salivary glands) and diffuse large B-cell lymphoma. Lymphomagenesis in primary SS patients is considered as a multistep process, with the first step being chronic stimulation of autoimmune B cells, especially B cells that produce rheumatoid factor at sites targeted by the disease. This increases the frequency of oncogenic mutation, leading to any dysfunction at checkpoints of autoimmune B-cell activation to transform into malignancy. A study's finding has concluded the continuous stimulation of autoimmune B cells, leading to subtle germinal abnormalities in genes having specific consequences in B cells, which underlies the susceptibility to lymphoma.
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According to Artemio De La Vega, CEO of De La Vega Development, "The core settled into the basement probably, approximately...I'd say 35 to 40 feet down into the basement, which is basically what is holding the tower." After the demolition, Dallas-based Lloyd D. Nabors Demolition, said they had a multistep plan to bring down the rest of the building. They planned on using a combination of a wrecking ball to destroy the upper portion of the core and a high-reach excavator to knock down the rest of it.. On February 24 they began the new phase of demolition. When the wrecking ball hit the building it appeared to do no damage at all.
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Although the procedure for the synthesis of the C60 fullerene is well established (generation of a large current between two nearby graphite electrodes in an inert atmosphere) a 2002 study described an organic synthesis of the compound starting from simple organic compounds.The numbers in image correspond to the way the new carbon carbon bonds are formed. :Multistep fullerene synthesis In the final step a large polycyclic aromatic hydrocarbon consisting of 13 hexagons and three pentagons was submitted to flash vacuum pyrolysis at 1100 °C and 0.01 Torr. The three carbon chlorine bonds served as free radical incubators and the ball was stitched up in a no-doubt complex series of radical reactions.
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Some proteins function as receptors and can be detected during purification steps by a ligand binding assay, often using a radioactive ligand. In order to evaluate the process of multistep purification, the amount of the specific protein has to be compared to the amount of total protein. The latter can be determined by the Bradford total protein assay or by absorbance of light at 280 nm, however some reagents used during the purification process may interfere with the quantification. For example, imidazole (commonly used for purification of polyhistidine-tagged recombinant proteins) is an amino acid analogue and at low concentrations will interfere with the bicinchoninic acid (BCA) assay for total protein quantification.
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Garrell's scientific research examines the behavior of molecules at liquid- liquid and liquid-solid interfaces, focusing in particular on how they control complex phenomena such as adsorption, adhesion, emulsification, wetting and liquid flow. She has worked on synthesizing new types of superparamagnetic nanoparticle catalysts as well as creating “lab-on-a-chip” devices that utilize droplet microfluidics for multistep chemical reactions. These applications include proteomics, the synthesis of millimeter-scale polymer particles and shells for inertial confinement fusion energy technology, and diagnostics and high-throughput drug discovery. Garrell is a member of the UCLA Biomedical Engineering faculty and the California NanoSystems Institute (CNSI) and has served on the Advisory Boards of C&EN; and Applied Spectroscopy, among other journals.
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After two years, Glidden abandoned production of cortisone to concentrate on Substance S. Julian developed a multistep process for conversion of pregnenolone, available in abundance from soybean oil sterols, to cortexolone. In 1952, Glidden, which had been producing progesterone and other steroids from soybean oil, shut down its own production and began importing them from Mexico through an arrangement with Diosynth (a small Mexican company founded in 1947 by Russell Marker after leaving Syntex). Glidden's cost of production of cortexolone was relatively high, so Upjohn decided to use progesterone, available in large quantity at low cost from Syntex, to produce cortisone and hydrocortisone. In 1953, Glidden decided to leave the steroid business, which had been relatively unprofitable over the years despite Julian's innovative work.
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Carcinogenesis is a multistep process; tumours also contain activated Ras, as well as mutation or downregulation of the tumour suppressor genes p53 in alimentary tract cancers and fragile histidine tetrads (FHIT) in urinary bladder cancers. Viral particles are not produced in either alimentary tract or urinary bladder tumours. Cows feeding on bracken are at risk of developing BPV-associated cancers These bracken-associated tumours might form a model for some types of human oesophageal cancer. Human papillomavirus DNA has been detected in around 18% of squamous cell carcinomas of the oesophagus, and there is an association between exposure to or consumption of bracken (which is used as a foodstuff and herbal remedy in South America, China, Japan, Korea and other countries) and risk of developing oesophageal cancer.
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Definition of Fine Chemicals (as opposed to Commodities and Specialties) Fine chemicals are complex, single, pure chemical substances, produced in limited quantities in multipurpose plants by multistep batch chemical or biotechnological processes. They are described by exacting specifications, used for further processing within the chemical industry and sold for more than $10/kg (see the comparison of fine chemicals, commodities and specialties). The class of fine chemicals is subdivided either on the basis of the added value (building blocks, advanced intermediates or active ingredients), or the type of business transaction, namely standard or exclusive products. Fine chemicals are produced in limited volumes (< 1000 tons/year) and at relatively high prices (> $10/kg) according to exacting specifications, mainly by traditional organic synthesis in multipurpose chemical plants.
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EVcort The EVcort was an experimental electric car produced from 1981 to 1994 by Electric Vehicle Associates of Cleveland OH and later by Soleq Corp. of Chicago IL.J. E. Francfort, R. R. Bassett, S. Briasco, W. Culliton, E. F. Duffy, R. A. Emmert, J. R. Hague. R. Hobbs, B. Graziano, I. J. Kakwan, S. Neal, L. Stefanakos and T. G. Ware: Site Operator Program Final Report for Fiscal Years 1992 through 1996 Lockheed Idaho Technologies Co., Idaho Falls, ID (United States), 1998 It consisted of a stock body and transmission from the Ford Escort, refitted with an electric propulsion system, every component of which was engineered and manufactured specifically for the car. It incorporated features such as regenerative braking and a multistep charging algorithm, that are common on modern electric vehicles but were quite innovative at the time.
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After secondary education at the Bundesrealgymnasium in Innsbruck, Lubich studied mathematics at the University of Innsbruck from 1977 to graduation with Magister degree in 1981. He was from 1979 to 1981 a student assistant in Innsbruck and from 1981 to 1983 a research associate in the Sonderforschungsbereich 123 Stochastische mathematische Modelle at the University of Heidelberg. He received his doctorate in 1983 from the University of Innsbruck with dissertation Zur Stabilität linearer Mehrschrittverfahren für Volterra-Gleichungen (On stability of linear multistep methods for Volterra equations) under Ernst Hairer and habilitated there in 1987. Lubich was from 1983 to 1987 a university assistant in Innsbruck, in 1986/87 an assistant at the University of Geneva, in 1987/88 a visiting professor at the IRMAR at the University of Rennes, and in 1988 a visiting professor at the University of Geneva.
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Reactions are known where the deuterated species reacts faster than the undeuterated analogue, and these cases are said to exhibit inverse kinetic isotope effects (IKIE). IKIE's are often observed in the reductive elimination of alkyl metal hydrides, e.g. (Me2NCH2CH2NMe2)PtMe(H). In such cases the C-D bond in the transition state, an agostic species, is highly stabilized relative to the C–H bond. An inverse effect can also occur in a multistep reaction if the overall rate constant depends on a pre- equilibria prior to the rate-determining step which has an inverse equilibrium isotope effect. For example, the rates of acid-catalyzed reactions are usually 2-3 times greater for reactions in D2O catalyzed by D3O+ than for the analogous reactions in H2O catalyzed by H3O+ This can be explained for a mechanism of specific hydrogen-ion catalysis of a reactant R by H3O+ (or D3O+). :H3O+ \+ R RH+ \+ H2O :RH+ \+ H2O → H3O+ \+ P The rate of formation of products is then d[P]/dt = k2[RH+] = k2K1[H3O+][R] = kobs[H3O+][R].
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