Reactivity

Belmont, CA, United States

Reactivity

Belmont, CA, United States

Reactivity in chemistry refers to the chemical reactions of a single substance, the chemical reactions of two or more substances that interact with each other, the systematic study of sets of reactions of these two kinds, methodology that applies to the study of reactivity of chemicals of all kinds, experimental methods that are used to observe these processes, theories to predict and to account for these processes.The chemical reactivity of a single substance covers its behaviour in which it: Decomposes Forms new substances by addition of atoms from another reactant or reactants Interacts with two or more other reactants to form two or more productsThe chemical reactivity of a substance can refer to the variety of circumstances in which it reacts, in combination with the: Variety of substances with which it reacts, Equilibrium point of the reaction Rate of the reactionThe term reactivity is related to the concepts of chemical stability and chemical compatibility. Wikipedia.

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News Article | December 9, 2015
Site: news.mit.edu

Are you a doodler or a scribe? Do you prefer pen and paper, or keyboard and mouse? Do you outline your thoughts, or let them flow freely? Maria Yang, an associate professor of mechanical engineering at MIT, believes the ways in which people formulate ideas — particularly when designing new products — can significantly influence those products’ success. “People’s strategies are so fascinating,” says Yang, who studies the creative strategies of designers in the very early stages of product development. “We observe them, and try to understand what their thought process is. Do different approaches work better than others? Because we want people to design better products and systems — that’s the bottom line.” As founder and director of MIT’s Ideation Lab, Yang helps designers — including architects, planners, designers, and engineers — improve their creative process by measuring the activities they engage in. She’s helped designers work toward a wide range of goals: developing software interfaces, coordinating complex space systems, and establishing infrastructure for residential solar power. In one of her recent papers, she says her research team explored the question, “If you sketch, or build prototypes, or explore using CAD [computer-aided design] models, can we measure if certain tools mean are linked with a better design result?” Yang says, “It’s not easy to change people. But if we give them better tools or processes, they can design better.” She also teaches students how to uncover ways to improve design in the world around them. In her course 2.00 (Introduction to Design), she tells students to look for “pain points” — situations in which users have difficulty in using a product, which are usually a ripe opportunity for better design. In one class, she recalls a student team came up with an idea for a product based on the experience of slicing a block of cheese with a chef’s knife. The pressure applied to the knife left a long indentation on the palm. As a solution, the team designed a device to distribute the force across the palm. “That was literally a pain point!” Yang exclaims. “The world tells you what it needs — it’s just not always obvious.” Yang was born and raised in West Lafayette, Indiana, where her father was a professor of aeronautics and astronautics at Purdue University. Her mother stayed home with Yang and her sister, and eventually earned a master’s degree in higher education administration, going on to teach Chinese calligraphy at the university. Looking back on her childhood, Yang now recognizes a design theme to her interests, though she didn’t realize it at the time. “As a kid, I liked a toy called ‘The Sunshine Family’ — a family of plastic dolls, not the glamorous kind,” Yang recalls. “The goal of the toy was to get kids to make products for dolls, so you would make an old toothpaste cap into a cup, and so forth. That’s basically the little kid version of what I do now.” In high school, she excelled in math and science, although she also took college courses in psychology and sociology. “That was my high school way of trying to understand users, though I didn’t know it at the time,” Yang says. When it came time for college, Yang applied and was accepted to MIT, where she remembers her undergraduate years as a mix of attitudes and ideas. “I went from living in Senior House, which was a little counterculture, to McCormick, which was a little more traditional,” Yang says. “I experienced the full spectrum.” She wound up majoring in mechanical engineering, and was instantly drawn to the design courses. Not surprisingly, she now teaches design courses like 2.00b (Toy Product Design) and 2.739 (Product Design and Development). After graduating from MIT, Yang headed to Stanford University, where she earned a master’s and PhD from the mechanical engineering department’s design division. During graduate school, she worked at Apple, developing software for collaborative interaction design teams, and at Lockheed Martin, designing software interfaces for design collaboration. The experience with industry prompted Yang to take a break from academia. After earning her PhD, she went to work for Reactivity, Inc., a consultancy and incubator in the Bay Area that helped startups with the design of first-generation prototypes. The experience was equal parts exhausting and exhilarating, although Yang increasingly felt the pull of academia. “I had always had this tension of whether I wanted to do design, or study design,” Yang says. “I missed academia, and the idea of being able to research the things I wanted to.” To ease back into academic life, Yang took a postdoctoral position at Caltech, which eventually led to a faculty position at MIT. “At MIT there are so many different viewpoints on design, all exciting, and I thought this would be a great place for me to find the right cohort of people to work with,” Yang recalls. In her product design research, a typical project might see Yang invite practicing Boston-area designers to her lab, where she gives them a design task, along with several tools to work with, such as sketching, CAD models, and foam blocks. She then records each designer as they work with a tool. Afterwards, she posts the designers’ final products, and crowdsources with hundreds of people to see which products they perceive as most user-friendly or desirable. “We found that with fast, lower-fidelity methods, like foam and sketching, people came up with more ideas — there’s a higher volume,” Yang says. Ultimately, quantity may be the key to a good product design. When faced with a blank page or computer screen, Yang advises students to defer judgment, and instead, write down any and every idea that comes to them — plausible or not. “If I have a room of 20 people with the same design problem, say a new kind of coffee cup for commuters, I can guarantee you that most of those 20 people will come up with many of the same first five ideas,” Yang says. “Once you get past 10, 20, 100 ideas — that’s the long tail, and those are ideas that have not been farmed before. So you just want to get your motor running.”


News Article | October 26, 2016
Site: www.eurekalert.org

DETROIT - A team led by Wayne State University School of Medicine researcher Mark Greenwald, Ph.D., will use a four-year, $2,279,723 competitively renewed grant from the National Institute on Drug Abuse (NIDA) of the National Institutes of Health to explore whether the opioid addiction treatment medication buprenorphine can decrease the magnitude and/or duration of responses to stressors faced by recovering addicts. The results of the study could reveal a new therapeutic feature of the drug, possibly helping drug-abstinent individuals avoid relapse. Greenwald is a professor and associate chair of research in Wayne State's Department of Psychiatry and Behavioral Neurosciences. He also directs the department's Substance Abuse Research Division. "Biobehavioral Studies of Opioid Seeking: Effect of Buprenorphine/Naloxone Dose on Experimental Stress Reactivity and Opioid Abstinence" is the third phase of a project initially funded by the NIDA in 2003. "We first developed and validated our experimental methods, then made changes over the course of the project to tackle more challenging questions," Greenwald said. "We want to address the terrible epidemic of opioid abuse, overdose and deaths that our society is witnessing." Opioids such as hydrocodone, oxycodone, morphine, codeine and heroin relieve pain by activating pain receptors in the brain; however, they also have high abuse potential. "Stress is a major contributor to all drug addictions and other behavioral health problems, so improving our understanding of the neurochemistry of stress and its effects on behavior have broader significance," Greenwald said. "Research on stress and addiction is a major growth area, but much of it has been done with laboratory animals. It's also important to recognize that although our research participants are generally healthy - because we screen them to exclude those with medical and psychiatric problems - in the real world, opioid abusers often have co-occurring psychiatric problems that reflect extraordinary challenges of stress and poverty." To promote the generalizability and clinical relevance of their findings, the researchers expanded study recruitment in this current cycle to all individuals with opioid use disorder, including those with prescription opioid use problems. More than 28,000 Americans died of an opioid-induced drug overdose in 2014, the most recent year for which data are available. About four people a day overdose from opioids in Michigan. "Without exaggeration, the current opioid epidemic is unprecedented. Regrettably, we see reports of opioid overdoses and deaths nearly every day in the media. The White House, Congress, Drug Enforcement Administration, Food and Drug Administration, Centers for Disease Control and Prevention, and the NIDA are all focused on this complex problem," Greenwald said. "This project is one piece of that challenging puzzle. Our longer-term objectives are to identify new therapies, for example, adjunctive medications, that attenuate stress reactivity. These could cut across all addictions and behavioral health problems to have a tremendous impact." Greenwald serves on the Wayne State University Task Force for Prescription Drug and Opioid Abuse, which last month proposed curriculum changes that would better prepare health professions students to work with persons who have substance abuse disorders, including more treatment education and tools to address increased challenges in prescribing controlled substances. "I'm interested in addressing problems that addiction treatment professionals face: What knowledge and tools can we bring to bear when a patient presents with a chronic, relapsing history of drug use? Most of my studies have focused on opioid addiction, and this grant project has specifically examined multiple determinants of opioid addiction," he said. From 2011 to 2015, the project team examined the effects of stress exposure on those seeking opioids. "We were first to translate an animal model into the human laboratory setting using a pharmacological stressor to investigate its effects on drug seeking," he said. "This stressor involves administering controlled doses of two drugs that can co-activate the brain's noradrenergic and glucocorticoid systems - yohimbine and hydrocortisone." The stressor can increase subjective and physiological markers of stress such as blood pressure, cortisol and anxiety, which are related to increased drug seeking, Greenwald explained. In the current cycle, the researchers will manipulate the buprenorphine dose across different weeks for each participant to determine whether the medication can dose-dependently blunt the effects of the stressor. They will also investigate whether stress responses during the initial part of the study predict subsequent relapse as they reduce the buprenorphine dose and for up to three months afterward. Naloxone overdose protection kits will be provided to enrolled participants. "I'm also excited to have added collaborations with two investigators who will significantly expand our array of biomarkers. The first is to measure chronic stress using cortisol levels in hair samples. The second is to measure indices of inflammation in blood samples. These will be quite innovative," he said. Wayne State University is one of the nation's pre-eminent public research universities in an urban setting. Through its multidisciplinary approach to research and education, and its ongoing collaboration with government, industry and other institutions, the university seeks to enhance economic growth and improve the quality of life in the city of Detroit, state of Michigan and throughout the world. For more information about research at Wayne State University, visit research.wayne.edu.


(Phys.org)—A team of researchers from Belgium and the U.S. has identified the active site of an iron-containing catalyst that has raised hopes for designing a practically useful catalyst that might make converting methane to methanol a possibility. In their paper published in the journal Nature, the researchers describe their efforts, what they discovered and why they believe their findings may lead to a practical way to convert methane to a more efficient energy resource. Jay Labinger, with the California Institute of Technology offers a News & Views piece outlining the work done by the team in the same journal issue. Scientists would very much like to find a way to convert methane (the primary component in natural gas) to methanol at room temperature. Doing so would offer a new source of liquid fuel that would be readily available due to the abundance of methane. Unfortunately, researchers have found it difficult going due to the unreactive nature of methane. In this new effort, the researchers report on progress they believe they have made in achieving that goal. As Labinger reports, that progress has come in two forms. The first was developing an aid for picking out the active site of a heterogeneous catalyst from a host of candidates. The second involved creating a design for converting methane to ethanol that would be both efficient and achievable at room temperature. To create their design, the team looked at an iron-containing structure generated via a zeolite (a type of mineral) that had been reported back in 1997. Since that time, researchers have used various techniques to ascertain that such structures contain another structure known as the α-Fe(ii) center, an important component in converting methane to methanol at room temperature. The new design involved proposing a means of describing a structure with an unusual monometallic iron center. They then conducted experiments using Mössbauer spectroscopy that indicated they were on the right track, which could lead eventually to finding the catalyst they are seeking. The finding by the team is good news, Labinger suggests, though he cautions that it is unlikely that the same approach could be used for solving other catalytic problems. More information: Benjamin E. R. Snyder et al. The active site of low-temperature methane hydroxylation in iron-containing zeolites, Nature (2016). DOI: 10.1038/nature19059 Abstract An efficient catalytic process for converting methane into methanol could have far-reaching economic implications. Iron-containing zeolites (microporous aluminosilicate minerals) are noteworthy in this regard, having an outstanding ability to hydroxylate methane rapidly at room temperature to form methanol. Reactivity occurs at an extra-lattice active site called α-Fe(II), which is activated by nitrous oxide to form the reactive intermediate α-O; however, despite nearly three decades of research, the nature of the active site and the factors determining its exceptional reactivity are unclear. The main difficulty is that the reactive species—α-Fe(II) and α-O—are challenging to probe spectroscopically: data from bulk techniques such as X-ray absorption spectroscopy and magnetic susceptibility are complicated by contributions from inactive 'spectator' iron. Here we show that a site-selective spectroscopic method regularly used in bioinorganic chemistry can overcome this problem. Magnetic circular dichroism reveals α-Fe(II) to be a mononuclear, high-spin, square planar Fe(II) site, while the reactive intermediate, α-O, is a mononuclear, high-spin Fe(IV)=O species, whose exceptional reactivity derives from a constrained coordination geometry enforced by the zeolite lattice. These findings illustrate the value of our approach to exploring active sites in heterogeneous systems. The results also suggest that using matrix constraints to activate metal sites for function—producing what is known in the context of metalloenzymes as an 'entatic' state—might be a useful way to tune the activity of heterogeneous catalysts.


News Article | December 14, 2016
Site: www.prweb.com

Whitehouse Laboratories, a division of AMRI, announces the addition of Disinfectant Efficacy testing capability to its Microbiology Laboratory. Clients will now have the opportunity to test their disinfectants for effectiveness based on AOAC and USP 1072 Disinfectants and Antiseptics. "The cleaning and disinfection process in any manufacturing environment should be well-defined and validated," said Brandon Zurawlow, associate director of container closure integrity testing. "Whitehouse Labs is pleased to offer this service to our customers as part of our mission of providing unrivaled analytical support of API to finished product packaging." This addition follows the recent additions of Endotoxin Testing per USP 85, Water for Pharmaceutical Purposes USP 1231, and Biological Reactivity Testing per USP 87. Whitehouse labs plans to introduce genotoxicity testing per OECD 471 and ISO 10993-4 AMES assays, as well as viral and microbial ingress and viral and bacterial filter retention testing in the near future. About Whitehouse Laboratories The leader in testing, Whitehouse Labs, a division of Albany Molecular Research Inc., offers comprehensive analytical services providing support for manufacturing from development to market. From analytical chemistry and material qualification to packaging optimization, Whitehouse Laboratories is the testing partner for the world's leading Pharmaceutical, Biotechnology, Medical Device, Life Sciences and Consumer Products organizations.


News Article | December 17, 2015
Site: phys.org

Historically, the way to alter the performance in reactive materials (i.e. thermites) has been to either change the formulation, or to change parameters, such as particle size, within a formulation. However, through 3D printing, a team of scientists and engineers at Lawrence Livermore National Laboratory and Harvard University has found that the architecture can play a strong role in exerting more control over the energy release rate of reactive composites. The team's findings are published in the December issue of the journal Advanced Materials, scheduled to be released online Dec.16. "3D printing has allowed us to make high-quality parts with the feature sizes commensurate with the length scales of dynamic phenomena," said Kyle Sullivan, a staff scientist and the paper's lead author. "It's allowed us to make precision geometries, with careful control over several length scales. With this spatial control, we wanted to examine how, and to what extent, this translates into controlling dynamic behavior." Through a 3D printing process called direct ink writing, researchers first constructed 3D conductive electrodes. Then, through another printing process called electrophoretic deposition (EPD), the team coated the surface of the conductive micro-architectures with a composite film of thermite nanoparticles. The researchers found that by creating the reactive material architectures, or RMAs, they could direct and manipulate the energy released by the material in ways never possible before. "The big message here is we're showing 3D printing can be used to change the dynamic behavior of materials," Sullivan said. "It's very promising moving forward." One advantage of 3D printing, said Lab engineer Eric Duoss, is that the process allowed the team to place a very precise amount of the materials onto a surface. "Traditional thermites are random mixtures of materials," Duoss said. "EPD gives you a tool to fix the mixing scale at the nanoscale. The film thickness, micro- and macroscale geometry can then be examined to elucidate the role of architecture on reactivity." Duoss, a materials scientist, engineer and co-author on the paper, said the team worked with several types of micro-architectures—flats, hurdles and channels—to tailor the thermite's energy release rates. Eventually, he said, the team plans to move to more complex structures, such as lattices, to see if there is a more dramatic impact. The findings, Sullivan said, could lead to new structural energetics, the discovery of previously unknown functions for reactive materials, and improve the safety and reliability of air bags, ejector seats or other items requiring a quick burst of energy. "If you look at the history of energetic materials, the scary part is that the performance is slowly plateauing," Sullivan said. "While it's only a matter of time for new formulations to be developed, this technique gives us an additional knob of using material architecture to tailor, and improve, the energetic materials we already have." Explore further: New light on novel additive manufacturing approach More information: Kyle T. Sullivan et al. Controlling Material Reactivity Using Architecture, Advanced Materials (2015). DOI: 10.1002/adma.201504286


Latest Environmental Trigger Test Evaluates 29 Pathogens that May be Lurking in a Patient's Body PHOENIX, AZ--(Marketwired - November 15, 2016) - Cyrex Laboratories, a clinical laboratory specializing in functional immunology and autoimmune reactivity, has announced the availability of its latest test available to Canadian patients, the Array 12 Pathogen Associated Immune Reactivity Screen. This test examines latent pathogens in the body that may be eliciting an immune response; negatively impacting health long after exposure and acute infection have occurred. Array 12 assesses the immune load from 29 viral, bacterial, fungal, parasitic and stealth organism antigens that may be latent in the body. The test is able to identify well-known pathogenic antigens -- such as the gingivitis bacteria that contributes to tooth decay, penicillium used to make antibiotics, and giardia parasites found in lakes and streams, to much lesser known pathogens such as the borrelia bacteria transmitted by ticks that causes lupus and cryptosporidium, a parasite identified in instances of municipal water supply contamination. "With the Array 12 screen, Cyrex is adding a key piece of the environmental triggers puzzle," said Jean Bellin, president of Cyrex Laboratories. "Array 12 is the most thorough test available for environmental triggers related to viral, bacterial, fungal, parasitic and stealth organism pathogens that may be latent in the body. This test offers physicians and patients unparalleled insight into the health of patients who may have fallen ill due to a pathogen encounter years prior to testing, or who may not have even experienced any symptoms and are unaware that any exposure occurred." Array 12 is available for $379 and is not intended for use as a diagnostic tool to confirm acute infection. Array 12 was developed with proprietary technology to look for IgG antibodies to pathogens that demonstrate immune reactivity long after initial symptoms or exposure occurred. This panel augments the environmental triggers testing offered at Cyrex; from the extensive foods, food additives and proteins/peptides on Arrays 3, 4 and the 10 series, to assessing reactivity to toxic chemicals and metals on Array 11, now Array 12 completes the environmental trigger puzzle by gauging the ongoing immune response to pathogenic exposure. Patients who may be suffering from immune reactivity or sensitivity as a result of latent pathogens in their body are encouraged to ask their physicians about Array 12. Also, as with all Cyrex testing, healthcare providers may request a clinical consultation to discuss Array 12 results with a member of our clinical consulting team. Physicians and other licensed healthcare professionals, as well as patients, interested in learning more about Array 12 or any of the Cyrex Arrays that are part of the Cyrex System, are encouraged to visit www.joincyrex.com for additional information. About Cyrex Laboratories Cyrex is a clinical immunology laboratory specializing in functional immunology and autoimmune reactivity. Cyrex offers multi-tissue antibody testing for the early detection and monitoring of today's complex autoimmune conditions. Cyrex develops innovative testing arrays through continuous collaboration with leading experts in medical research and clinical practice. Cyrex technology is built on four pillars of excellence, including the antigen purification system, optimized antigen concentration, antigen-specific validation and parallel testing technology. Cyrex is a CLIA licensed laboratory based in Phoenix, Arizona and holds a Medical Device Establishment License in Canada.


Latest Environmental Trigger Test Evaluates 29 Pathogens that May be Lurking in a Patient's Body PHOENIX, AZ--(Marketwired - November 15, 2016) - Cyrex Laboratories, a clinical laboratory specializing in functional immunology and autoimmune reactivity, has announced the availability of its latest test, the Array 12 Pathogen Associated Immune Reactivity Screen. This test examines latent pathogens in the body that may be eliciting an immune response; negatively impacting health long after exposure and acute infection have occurred. Array 12 assesses the immune load from 29 viral, bacterial, fungal, parasitic and stealth organism antigens that may be latent in the body. The test is able to identify well-known pathogenic antigens -- such as the gingivitis bacteria that contributes to tooth decay, penicillium used to make antibiotics, and giardia parasites found in lakes and streams, to much lesser known pathogens such as the borrelia bacteria transmitted by ticks that causes lupus and cryptosporidium, a parasite identified in instances of municipal water supply contamination. "With the Array 12 screen, Cyrex is adding a key piece of the environmental triggers puzzle," said Jean Bellin, president of Cyrex Laboratories. "Array 12 is the most thorough test available for environmental triggers related to viral, bacterial, fungal, parasitic and stealth organism pathogens that may be latent in the body. This test offers physicians and patients unparalleled insight into the health of patients who may have fallen ill due to a pathogen encounter years prior to testing, or who may not have even experienced any symptoms and are unaware that any exposure occurred." Array 12 is available for $379 and is not intended for use as a diagnostic tool to confirm acute infection. Array 12 was developed with proprietary technology to look for IgG antibodies to pathogens that demonstrate immune reactivity long after initial symptoms or exposure occurred. This panel augments the environmental triggers testing offered at Cyrex; from the extensive foods, food additives and proteins/peptides on Arrays 3, 4 and the 10 series, to assessing reactivity to toxic chemicals and metals on Array 11, now Array 12 completes the environmental trigger puzzle by gauging the ongoing immune response to pathogenic exposure. Patients who may be suffering from immune reactivity or sensitivity as a result of latent pathogens in their body are encouraged to ask their physicians about Array 12. Also, as with all Cyrex testing, healthcare providers may request a clinical consultation to discuss Array 12 results with a member of our clinical consulting team. Physicians and other licensed healthcare professionals, as well as patients, interested in learning more about Array 12 or any of the Cyrex Arrays that are part of the Cyrex System, are encouraged to visit www.joincyrex.com for additional information. About Cyrex Laboratories Cyrex is a clinical immunology laboratory specializing in functional immunology and autoimmune reactivity. Cyrex offers multi-tissue antibody testing for the early detection and monitoring of today's complex autoimmune conditions. Cyrex develops innovative testing arrays through continuous collaboration with leading experts in medical research and clinical practice. Cyrex technology is built on four pillars of excellence, including the antigen purification system, optimized antigen concentration, antigen-specific validation and parallel testing technology. Cyrex is a CLIA licensed laboratory based in Phoenix, Arizona and holds a Medical Device Establishment License in Canada.


Moreau J.,Reactivity | Marchand-Brynaert J.,Reactivity
European Journal of Organic Chemistry | Year: 2011

A practical synthesis of α,ω-bifunctional linkers is described that is based on three building blocks, namely, thioctic acid, a spacer-arm of seven ethylene glycol units, and a functional motif dedicated to the selective immobilization of purposely tagged proteins. Such representative motifs are biotin, haloacetamide, maleimide, and nitrilotriacetic acid derivatives. The building blocks are connected through alkyl, amide, and/or carbamate linkages. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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