568 research outputs found

    Solid-State Forms of β-Resorcylic Acid: How Exhaustive Should a Polymorph Screen Be?

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    An extensive experimental screen, coupled with a computational study, revealed seven new solid-state forms of β-resorcylic acid. The known, stable polymorph II° shows a reversible phase transformation to the new, kinetically stable, probably disordered high temperature form I. The study provides a consistent picture of the solid-state of β-resorcylic acid

    The Mechanism Design Approach to Student Assignment

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    The mechanism design approach to student assignment involves the theoretical, empirical, and experimental study of systems used to allocate students into schools around the world. Recent practical experience designing systems for student assignment has raised new theoretical questions for the theory of matching and assignment. This article reviews some of this recent literature, highlighting how issues from the field motivated theoretical developments and emphasizing how the dialogue may be a road map for other areas of applied mechanism design. Finally, it concludes with some open questions.National Science Foundation (U.S.

    Accelerated discovery of two crystal structure types in a complex inorganic phase field

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    The discovery of new materials is hampered by the lack of efficient approaches to the exploration of both the large number of possible elemental compositions for such materials, and of the candidate structures at each composition1. For example, the discovery of inorganic extended solid structures has relied on knowledge of crystal chemistry coupled with time-consuming materials synthesis with systematically varied elemental ratios2,3. Computational methods have been developed to guide synthesis by predicting structures at specific compositions4,5,6 and predicting compositions for known crystal structures7,8, with notable successes9,10. However, the challenge of finding qualitatively new, experimentally realizable compounds, with crystal structures where the unit cell and the atom positions within it differ from known structures, remains for compositionally complex systems. Many valuable properties arise from substitution into known crystal structures, but materials discovery using this approach alone risks both missing best-in-class performance and attempting design with incomplete knowledge8,11. Here we report the experimental discovery of two structure types by computational identification of the region of a complex inorganic phase field that contains them. This is achieved by computing probe structures that capture the chemical and structural diversity of the system and whose energies can be ranked against combinations of currently known materials. Subsequent experimental exploration of the lowest-energy regions of the computed phase diagram affords two materials with previously unreported crystal structures featuring unusual structural motifs. This approach will accelerate the systematic discovery of new materials in complex compositional spaces by efficiently guiding synthesis and enhancing the predictive power of the computational tools through expansion of the knowledge base underpinning them

    The role of P2X7 in pain and inflammation

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    The P2X7 purinoceptor is unique amongst the P2X receptor family in that its activation is able to stimulate the release of mature, biologically active interleukin-1β (IL-1β), as well as a variety of other proinflammatory cytokines. Coupled with the predominate localisation of this receptor to immunocytes of haemopoetic origin, this receptor is an obvious candidate to play a major and pivotal role in processes of pain and inflammation. Using genetically modified animals that lack the P2X7 receptor, several investigators have shown that these mice do indeed demonstrate a blunted inflammatory response, and fail to develop pain following both inflammatory and neuropathic insult. These animals also show altered cytokine production in response to inflammatory stimulus, which is far broader than merely modulation of IL-1β release. In this short article, we review the role of the P2X7 receptor in modulating the release of cytokines and other mediators, and discuss the findings made from P2X7 receptor-deficient animals. As well as highlighting outstanding questions regarding this intriguing receptor, we also speculate as to the potential therapeutic benefit of P2X7 receptor modulation

    Vaccine hesitancy for COVID19: what is the role of statistical literacy?

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    IntroductionVaccination is an important measure used to control the spread of COVID19. The estimation of risk versus benefit of vaccination is based on the understanding of information about the vaccine. Statistics are frequently part of communications about COVID19. Individuals that do not have an adequate foundation of statistical knowledge may not be able to properly assess associated risks and benefits. This study aims to assess the association between statistical literacy and hesitation to receive the COVID19 vaccine.MethodsA nationally representative sample of 2,138 adults, recruited through CINT United States, Inc., (Lawrenceville, NJ; http://www.cint.com), completed an internet survey in the summer of 2021. This survey collected demographic measures and information about COVID19 vaccination status. The competency of respondents on various basic statistical concepts was assessed along with the corresponding confidence of respondents in their answers. A multivariable logistic regression model was constructed to assess the relationship between vaccine hesitancy and statistical literacy while controlling for covariates of interest.ResultsStatistical literacy was found to have a negligible association with COVID19 vaccine hesitancy (OR 1.01; 95% CI 1.00–1.02). In addition, differences in the proportion receiving the COVID19 vaccine between political affiliations, income levels, race groups, and ethnicities were observed.DiscussionThe statistical knowledge of the general American public is not commensurate with the need to be literate in basic statistical concepts in the data-driven world in which we live. An effective way to stem vaccine hesitancy may rely on increased statistical knowledge to not be biased by preconceived beliefs shaped by misinformation
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