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1.
J Anesth Hist ; 6(1): 1-7, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32473760

RESUMO

When teenaged Henry Jacob Bigelow was an undergraduate at Harvard College in 1833-1837, he prepared nitrous oxide gas for demonstrations to other students. Bigelow's son, William Sturgis Bigelow, related the claim, and there is an eyewitness account from Augustus Goddard Peabody, a fellow Harvard undergraduate with Bigelow. Peabody wrote to Henry David Thoreau about a nitrous frolic. College chemistry primed Bigelow to support the concept of inhaled surgical anesthesia when the idea came to Boston in 1845-1846. Bigelow's chemistry professor was John White Webster. According to Harvard alumnus Edward Everett Hale, in addition to demonstrating effects of nitrous oxide, Webster presciently treated two cases of carbon monoxide poisoning with copious volumes of synthetic oxygen gas. The career of Webster was inhibited by financial difficulties that were suspected to be contributory when he was convicted of the 1849 murder of physician George Parkman at the Harvard Medical School, then adjacent to Massachusetts General Hospital and its Ether Dome. Webster suffered the death penalty in 1850.


Assuntos
Anestésicos Inalatórios/história , Óxido Nitroso/história , Boston , Química/educação , Química/história , Éter/história , Docentes/história , História do Século XIX , Hospitais de Ensino/história , Humanos , Universidades/história
2.
PLoS One ; 15(5): e0233431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437417

RESUMO

It is well-documented that the representation of women and racial/ethnic minorities diminishes at higher levels of academia, particularly in science, technology, engineering, and math (STEM). Sense of belonging-the extent to which an individual believes they are accepted, valued, and included in a community-is often emphasized as an important predictor of retention throughout academia. While literature addressing undergraduate sense of belonging is abundant, there has been little investigation of sense of belonging in graduate communities. Because graduate training is required to generate new scientific leaders, it is important to understand and address sense of belonging at the graduate level-paying explicit attention to devising strategies that can be used to increase representation at higher levels of academia. Here, a visual narrative survey and item response modeling are used to quantify sense of belonging among graduate students, postdoctoral researchers, and faculty within the Department of Chemistry at the University of California, Berkeley. Results suggest that graduate students, postdoctoral researchers, and faculty all experience impostor phenomenon. Respondents struggle most with maintaining positive self-perceptions of their productivity, capabilities as a scientist, and success-particularly in comparison to their peers. Communicating about science with peers, talking about teaching hurdles, and engaging in mentoring relationships also contribute significantly to sense of belonging. Faculty members have the highest sense of belonging, while senior graduate students and postdoctoral researchers are least likely to feel a sense of belonging. Additionally, graduate students and postdoctoral researchers who identify as underrepresented, as well as those who submit manuscripts for publication less than their peers, are less likely to feel a sense of belonging. This is the first study to generate a quantitative, nuanced understanding of sense of belonging within the entire graduate academic community of an R1 STEM department. We envision that these methods can be implemented within any research-focused academic unit to better understand the challenges facing community members and identify factors to address in promoting positive culture change. Furthermore, these methods and results should provide a foundation for devising interventions that academic stakeholders can use to directly improve graduate education.


Assuntos
Química/educação , Educação de Pós-Graduação , Autoimagem , Estudantes/psicologia , Adulto , Docentes , Feminino , Humanos , Masculino , Tutoria , Pessoa de Meia-Idade , Grupos Minoritários
3.
Acta bioeth ; 26(1): 101-106, mayo 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1114603

RESUMO

As declared by the United Nations, 2019 is the International Year of the Periodic Table of Chemical Elements. Accordingly, an innovative new Periodic Table of Chemical Elements and Ethics [PETE] has been developed as an educational tool for secondary and university STEM (Science, Technology, Engineering and Mathematics) education. The tool is designed to be used in a case-based approache that is feasible to both individual and small group learners. Specifically, with the new periodic table, STEM becomes aligned with STSE (Science and Technology on Society and Environment), laying a curricular pathway for integrating discussions of ethics into the teaching of chemistry. Presented is the table, as well as sources for pairable ethics cases, and guidance for teachers to create curriculum which facilitates connections between ethics, chemistry, and society.


Según lo declarado por las Naciones Unidas, 2019 es el Año Internacional de la Tabla Periódica de Elementos Químicos. En consecuencia, se ha desarrollado una nueva e innovadora tabla periódica de elementos químicos y ética [PETE] como una herramienta educativa para la educación secundaria y universitaria STEM (Ciencia, Tecnología, Ingeniería y Matemáticas). La herramienta está diseñada para usarse en un enfoque basado en casos que sea factible tanto para estudiantes individuales como para grupos pequeños. Específicamente, con la nueva tabla periódica, STEM se alinea con STSE (Ciencia y Tecnología en Sociedad y Medio Ambiente), estableciendo una vía curricular para integrar las discusiones de ética en la enseñanza de la química. Se presenta la tabla, así como las fuentes de casos de ética que se pueden pactar, y orientación para que los maestros creen un plan de estudios que facilite las conexiones entre la ética, la química y la sociedad.


Como declarado pelas Nações Unidas, 2019 é o Ano Internacional da Tabela Periódica de Elementos Químicos. Portanto, uma inovadora e nova Tabela Periódica de Elementos Químicos e Ética (PETE, sigla em inglês) foi desenvolvida como uma ferramenta educacional para educação STEM (sigla em inglês para Ciência, Tecnologia, Engenharia e Matemática) secundária e universitária. A ferramenta é elaborada para ser usada em uma abordagem baseada em casos, viável tanto para aprendizagem individual como de pequenos grupos. Especificamente, com a nova tabela periódica, STEM se alinha com STSE (sigla em inglês para Ciência e Tecnologia na Sociedade e Ambiente), estabelecendo uma via curricular para integrar discussões de ética no ensino de química. Apresenta-se a tabela, bem como fontes de casos éticos pareados, e orientação para professores criarem um currículo que facilite conexões entre ética, química e sociedade.


Assuntos
Ciência/educação , Química/educação , Química/ética , Tecnologia Educacional , Educação/ética , Periodicidade , Ciência/ética , Currículo , Ensino Fundamental e Médio , Educação Superior
5.
Proc Natl Acad Sci U S A ; 117(16): 8794-8803, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32253310

RESUMO

Multiple-choice examinations play a critical role in university admissions across the world. A key question is whether imposing penalties for wrong answers on these examinations deters guessing from women more than men, disadvantaging female test-takers. We consider data from a large-scale, high-stakes policy change that removed penalties for wrong answers on the national college entry examination in Chile. The policy change reduced a large gender gap in questions skipped. It also narrowed gender gaps in performance, primarily among high-performing test-takers, and in the fields of math, social science, and chemistry.


Assuntos
Teste de Admissão Acadêmica/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Universidades/normas , Química/educação , Química/normas , Química/estatística & dados numéricos , Chile , Comportamento de Escolha , Feminino , Humanos , Masculino , Matemática/educação , Matemática/normas , Matemática/estatística & dados numéricos , Políticas , Ciências Sociais/educação , Ciências Sociais/normas , Ciências Sociais/estatística & dados numéricos , Estudantes/psicologia , Universidades/estatística & dados numéricos
6.
PLoS Biol ; 18(4): e3000650, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32298254

RESUMO

Encouragement of students across all communities through scientific outreach programs is critical to engaging the next generation, exciting young minds to pursue careers in science and medicine. Herein, we present a uniquely structured and widely influential science outreach program. Founded in 2005, the Duke Chemistry Outreach (DCO) employs a pedagogical approach to outreach that aims to teach its audience a new scientific concept, while instilling a pure enjoyment of science. DCO has performed 583 events reaching over 70,000 participants throughout 2,270 hours, with the majority of events in Durham, the surrounding North Carolinian communities, and across 8 other states. The flexibility and diversity of this outreach program creates a framework amendable for others to adopt in both secondary and higher education settings.


Assuntos
Química/educação , Relações Comunidade-Instituição , Ciência/educação , Universidades , Relações Comunidade-Instituição/economia , Humanos , North Carolina , Pesquisadores , Estudantes
7.
Yakugaku Zasshi ; 140(1): 43-46, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-31902884

RESUMO

After finishing my Ph.D., I had the opportunity to work as a postdoc in the Division of Redox Regulation (laboratory of Tobias Dick) at the German Cancer Research Center in Heidelberg for almost three years. Although cultural differences between Japan and Germany made my time in Germany hectic, the experience expanded my worldview as well as my research expertise. Here I would like to share my experience in conducting research abroad and give my opinion about its significance. I hope that this symposium review will be helpful to students interested in researching abroad and will give them a positive impression and encouragement.


Assuntos
Academias e Institutos , Biologia/educação , Química/educação , Educação de Pós-Graduação , Pesquisa , Diversidade Cultural , Alemanha , Humanos , Japão
8.
Mol Cell ; 77(3): 441-442, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-31978321
10.
Phys Chem Chem Phys ; 22(3): 1392-1399, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31859314

RESUMO

Detailed knowledge of intramolecular hydrogen bonds, including their nanomechanics, in a peptide secondary structure is crucial for understanding mechanisms of numerous biochemical processes. Single-molecule force spectroscopy has become a powerful tool to study directly the mechanical properties of single biopolymers and monitoring the hydrogen bonds. However, the interpretation of such experiments, due to their poor temporal resolution relative to the rate of intramolecular dynamics, requires the support of molecular simulations. In this work, we provide a methodology for determining the kinetic and energetic characteristics of hydrogen bonds in a template model of the protein secondary structure. Our approach, based on the steered molecular dynamics method, employs dynamic force spectroscopy calculations and uses two advanced theoretical models of force-induced unbinding. A systematic analysis of the simulated data with these models allowed for quantitative characterization of a single hydrogen bond in the α-helix of the AAKA(AEAAKA)5AC peptide model and detailed explanation of the mechanism of the α-helix unfolding. The methodology proposed here may be extended to other molecular structures stabilized by internal hydrogen bonds.


Assuntos
Química/métodos , Ligação de Hidrogênio , Modelos Químicos , Peptídeos/química , Simulação por Computador , Estrutura Secundária de Proteína , Análise Espectral
12.
Interdiscip Sci ; 11(4): 738-747, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31486019

RESUMO

BACKGROUND: Computational prediction of inhibition efficiency (IE) for inhibitor molecules is a crucial supplementary way to design novel molecules that can efficiently inhibit corrosion onto metallic surfaces. PURPOSE: Here we are dedicated to developing a new machine learning-based predictor for the inhibition efficiency (IE) of benzimidazole derivatives. METHODS: First, a comprehensively numerical representation was given on inhibitor molecules from all aspects of energy, electronic, topological, physicochemical and spatial properties based on 3-D structures and 150 valid structural descriptors were obtained. Then, a thorough investigation of these structural descriptors was implemented. The multicollinearity-based clustering analysis was performed to remove the linear correlated feature variables, so 47 feature clusters were produced. Meanwhile, Gini importance by random forest (RF) was used to further measure the contributions of the descriptors in each cluster and 47 non-linear descriptors were selected with the highest Gini importance score in the corresponding cluster. Further, considering the limited number of available inhibitors, different feature subsets were constructed according to the Gini importance score ranking list of 47 descriptors. RESULTS: Finally, support vector machine (SVM) models based on different feature subsets were tested by leave-one-out cross validation. Through comparisons, the optimal SVM model with the top 11 descriptors was achieved based on Poly kernel. This model yields a promising performance with the correlation coefficient (R) and root-mean-square error (RMSE) of 0.9589 and 4.45, respectively, which indicates that the method proposed by us gives the best performance for the current data. CONCLUSION: Based on our model, 6 new benzimidazole molecules were designed and their IE values predicted by this model indicate that two of them have high potential as outstanding corrosion inhibitors.


Assuntos
Benzimidazóis/síntese química , Biologia Computacional/métodos , Aprendizado de Máquina , Relação Quantitativa Estrutura-Atividade , Máquina de Vetores de Suporte , Algoritmos , Química/métodos , Análise por Conglomerados , Conservação dos Recursos Naturais , Corrosão , Hidrazinas/química , Imageamento Tridimensional , Modelos Lineares , Metais/química , Valor Preditivo dos Testes , Eletricidade Estática
14.
Internist (Berl) ; 60(10): 1014-1020, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31541280

RESUMO

Combinatorial procedures have become established in recent years as alternatives to rational design in drug research, particularly when no structural information is available. This article presents the principle that was originally developed by three scientists and was honored with the Nobel Prize for Chemistry in 2018. Furthermore, the application in the field of monclonal antibodies is discussed.


Assuntos
Anticorpos Monoclonais , Técnicas de Visualização da Superfície Celular , Química/história , Técnicas de Química Combinatória , Desenho de Fármacos , Biologia Molecular , Prêmio Nobel , História do Século XX , História do Século XXI , Humanos
16.
Anal Bioanal Chem ; 411(25): 6531-6532, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31506718
17.
Nat Methods ; 16(10): 933, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31562477
18.
Chimia (Aarau) ; 73(7): 637-638, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31431224
20.
Orig Life Evol Biosph ; 49(3): 111-145, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31399826

RESUMO

In this review, we describe some of the central philosophical issues facing origins-of-life research and provide a targeted history of the developments that have led to the multidisciplinary field of origins-of-life studies. We outline these issues and developments to guide researchers and students from all fields. With respect to philosophy, we provide brief summaries of debates with respect to (1) definitions (or theories) of life, what life is and how research should be conducted in the absence of an accepted theory of life, (2) the distinctions between synthetic, historical, and universal projects in origins-of-life studies, issues with strategies for inferring the origins of life, such as (3) the nature of the first living entities (the "bottom up" approach) and (4) how to infer the nature of the last universal common ancestor (the "top down" approach), and (5) the status of origins of life as a science. Each of these debates influences the others. Although there are clusters of researchers that agree on some answers to these issues, each of these debates is still open. With respect to history, we outline several independent paths that have led to some of the approaches now prevalent in origins-of-life studies. These include one path from early views of life through the scientific revolutions brought about by Linnaeus (von Linn.), Wöhler, Miller, and others. In this approach, new theories, tools, and evidence guide new thoughts about the nature of life and its origin. We also describe another family of paths motivated by a" circularity" approach to life, which is guided by such thinkers as Maturana & Varela, Gánti, Rosen, and others. These views echo ideas developed by Kant and Aristotle, though they do so using modern science in ways that produce exciting avenues of investigation. By exploring the history of these ideas, we can see how many of the issues that currently interest us have been guided by the contexts in which the ideas were developed. The disciplinary backgrounds of each of these scholars has influenced the questions they sought to answer, the experiments they envisioned, and the kinds of data they collected. We conclude by encouraging scientists and scholars in the humanities and social sciences to explore ways in which they can interact to provide a deeper understanding of the conceptual assumptions, structure, and history of origins-of-life research. This may be useful to help frame future research agendas and bring awareness to the multifaceted issues facing this challenging scientific question.


Assuntos
Biologia/história , Química/história , Historiografia , Informática/história , Origem da Vida , Paleontologia/história , Filosofia/história , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Biologia Molecular/história
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