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1.
Biochem Mol Biol Educ ; 49(3): 320-322, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33835679

RESUMO

The COVID-19 pandemic led to an abrupt suspension of face-to-face teaching activities in higher education institutions across the globe. The instructors and faculty at most institutions have had to adapt, invent, and implement adjustments quickly to adopt an online learning environment. This has been an extraordinarily challenging time for both students and instructors, particularly as many were not aware of the affordances and weaknesses of the online learning environment before it was uptaken. Particularly for chemistry and related disciplines, this change in delivery mode is even more disruptive in courses that have laboratory components due to loss of access to laboratories. As a teaching community, it was our responsibility to respond quickly and effectively to students' learning needs during this unprecedented global crisis. In our course, we provided succinct pre-recorded lecture-videos by topic rather than live-streaming of lectures. The recordings were made available to students a minimum of 24 h before the scheduled lecture time. Students were then provided opportunities to attend live tutorial sessions (held on Zoom and live Q&A feature on Piazza) if they had any questions that they wanted to ask the lecturer directly. We believe that the asynchronous sessions were more equitable than synchronous ones. This meant that students with difficult and challenging home/learning environments (i.e., disruptions at home, work/family schedules, poor internet, limited access to devices, etc.) were minimally disadvantaged. The approach worked well in general for teaching chemistry to pharmacy students and we believe that it can be adopted for other subjects.


Assuntos
Química/educação , Educação a Distância , /epidemiologia , Química Farmacêutica/educação , Currículo , Educação em Farmácia/métodos , Humanos , Nova Zelândia/epidemiologia , Pandemias , Universidades
2.
Molecules ; 26(3)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535612

RESUMO

Sonochemistry can be broadly defined as the science of chemical and physical transformations produced under the influence of sound. The use of sound energy is rather a young branch of chemistry and does not have the clear definitive rules of other, more established, divisions such as those in cycloaddition reactions or photochemistry. Nevertheless, there are a few guidelines which can help to predict what is going to happen when a reaction mixture is submitted to ultrasonic irradiation. Jean-Louis Luche, formulated some ideas of the mechanistic pathways involved in sonochemistry more than 30 years ago. He introduced the idea of "true" and "false" sonochemical reactions both of which are the result of acoustic cavitation. The difference was that the former involved a free radical component whereas only mechanical effects played a role the latter. The authors of this paper were scientific collaborators and friends of Jean-Louis Luche during those early years and had the chance to discuss and work with him on the mechanisms of sonochemistry. In this paper we will review the original rules (laws) as predicted by Jean-Louis Luche and how they have been further developed and extended in recent years.


Assuntos
Química/instrumentação , Radicais Livres/química , Radicais Livres/metabolismo , Marcadores de Spin , Ultrassom/instrumentação , Ultrassom/métodos , Humanos
3.
Carbohydr Polym ; 258: 117688, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593561

RESUMO

Since shelf life of perishable foods is short, a compelling challenge is to prolong the freshness of foods with a cost-effective strategy. A perishable fruit, the strawberry, is chosen as a model perishable food and an edible film coating is applied to it using carboxymethylated cellulose nanofibers (CM-CNFs) stabilized by cationic salts. A transparent and impermeable CM-CNF film is formed at the strawberry surface using a dip coating process. The formation of the film is dependent on the electrostatic interaction between anionic CM-CNF and salt cations. Physical properties of the film are characterized and the effectiveness of edible film coating on the freshness of perishable fruit is evaluated by the measurement of weight loss, CO2 release, firmness, total solid sugar and acidity. Cellulose nanofiber is a promising cost-effective material appropriate for use as an edible coating that contributes to the long-term storage and prolonged freshness of foods.


Assuntos
Celulose/química , Reagentes para Ligações Cruzadas/química , Filmes Comestíveis , Conservação de Alimentos/instrumentação , Fragaria/metabolismo , Nanofibras/química , Cálcio/química , Dióxido de Carbono/química , Cátions , Química/métodos , Conservação de Alimentos/métodos , Íons , Eletricidade Estática
4.
Molecules ; 25(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371263

RESUMO

In this tribute to John B. Goodenough I will describe how John's talk on the metal-to-nonmetal transition of vanadium oxide VO2, presented at the Bordeaux Conference (September 1964) attended by inorganic chemists, metallurgists, crystallographers, thermodynamicists and physicists, provided a pioneering vision of interdisciplinary research to come. John gave a complete description of the paradigm on how the physical properties of a solid depend on its structure and bonding, by employing the chemical notions as local distortions and interatomic distances as well as the physics notions such as band width and the Hubbard on-site repulsion U. I will illustrate how inspiring John's ideas were, by discussing the research examples of my own research group in the sixties-seventies. The fundamental approach of John B. Goodenough to Solid State Chemistry, leading particularly to lithium battery applications, is at the heart of the 2019 Nobel Prize awarded to John.


Assuntos
Óxidos/química , Vanádio/química , Química/métodos , Humanos , Fenômenos Físicos
5.
PLoS One ; 15(12): e0243913, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332441

RESUMO

We analyse academic success using a genealogical approach to the careers of over 95,000 scientists in mathematics and associated fields in physics and chemistry. We look at the effect of Ph.D. supervisors (one's mentors) on the number of Ph.D. students that one supervises later on (one's mentees) as a measure of academic success. Supervisors generally provide important inputs in Ph.D. projects, which can have long-lasting effects on academic careers. Moreover, having multiple supervisors exposes one to a diversity of inputs. We show that Ph.D. students benefit from having multiple supervisors instead of a single one. The cognitive diversity of mentors has a subtler effect in that it increases both the likelihood of success (having many mentees later on) and failure (having no mentees at all later on). We understand the effect of diverse mentorship as a high-risk, high-gain strategy: the recombination of unrelated expertise often fails, but sometimes leads to true novelty.


Assuntos
Sucesso Acadêmico , Escolha da Profissão , Matemática/estatística & dados numéricos , Ciência/estatística & dados numéricos , Química/estatística & dados numéricos , Feminino , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Masculino , Matemática/história , Mentores/história , Física/história , Física/estatística & dados numéricos , Pesquisadores/história , Pesquisadores/psicologia , Estudantes/história , Estudantes/estatística & dados numéricos
6.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321988

RESUMO

Materials chemistry has been one of the most talked-about areas of materials research over the past decades [...].


Assuntos
Química , Ciência dos Materiais , Química/métodos , Ciência dos Materiais/métodos
7.
Postepy Biochem ; 66(3): 287-293, 2020 09 30.
Artigo em Polonês | MEDLINE | ID: mdl-33315319

RESUMO

Medical students' active involvement in the process of learning and acquiring the knowledge allow to develop passions and skills. The aim of learning should be to increase the number of students involved and satisfied with the learning process. Positive results can be achieved by creating attractive and accessible conditions for students to learn. The search for techniques that increase student involvement, the introduction of new teaching methods and student-oriented education should be a permanent element of modern teaching. Short courses, particularly with a small number of participants, pose certain organizational challenges. The students start the course often with significantly different initial basic knowledge and background. Additionally small number of students highlights their different expectations. In order to interest all students, a number of modern, active teaching methods should be implemented and applied. Thus we ultimately will achieve the result in increased students satisfaction with the simultaneous achievement of the intended learning outcomes within the course. Moreover one of the most important goals of the course is for the student to acquire such skills and knowledge that will be future-job useful for them. The aim of this article is to describe the changes planned in the course "Biochemistry with Elements of Chemistry" for Emergency Medical Services. The article focuses on presenting proposals for educational techniques, the application of which will create conditions for improving and equalizing student learning experience. The planned modifications are expected to increase the satisfaction of educators from teaching and students from learning. The basic change in the course concept will be the transition from the general transfer of knowledge in form of information presentation, to student centered learning and their active participation in the learning process. It is planned to introduce remote (on-line) teaching using e-learning platforms, and available online interactive teaching tools such as polleverywhere (https://www.polleverywhere.com/) or perusall (https://perusall.com/inactivity). Moreover, Case based learning, activation techniques embedded in the context of the future emergency services profession, such as role-playing, critical analysis of results or reporting, will be introduced.


Assuntos
Bioquímica/educação , Química/educação , Aprendizagem , Estudantes de Medicina/psicologia , Ensino , Humanos
9.
An Real Acad Farm ; 86(4): 301-310, oct.-dic. 2020.
Artigo em Espanhol | IBECS | ID: ibc-199665

RESUMO

Las investigadoras Emmanuelle Charpentier y Jennifer Doudna han recibido el Premio Nobel de Química del año 2020 por "el desarrollo de un método de edición genética", tal y como proclama la escueta pero suficiente justificación aportada por la Academia Sueca de Ciencias, responsable de la selección y elección de los premiados en esta categoría. La palabra CRISPR (acrónimo en inglés de Clustered Regularly Interspaced Short Palindromic Repeats) que corresponde, en español, a las repeticiones cortas palindrómicas agrupadas y regularmente espaciadas, descritas por el microbiólogo español de la Universidad de Alicante, Francisco Juan Martínez Mojica, no aparece en la frase resaltada del galardón pero, inmediatamente, el mundo entero supo que este premio Nobel de Química se lo llevaban las "CRISPR", las famosas herramientas de edición genética, descritas inicialmente por Mojica como elementos de un complejo y eficaz sistema de defensa en procariotas y que, gracias al talento y la visión de estas dos investigadoras, fueron propuestas para ser utilizadas, fuera de contexto, para la edición de cualquier gen de cualquier ser vivo. En esta revisión señalaré los puntos clave que permitieron a Charpentier y Doudna obtener, merecidamente, este premio y, por supuesto, subrayaré el papel que han jugado muchos otros investigadores, como el propio Mojica


Two researchers, Emmanuelle Charpentier and Jennifer Doudna, have received the 2020 Nobel Prize in Chemistry for "the development of a genetic editing method", as proclaimed by the brief but sufficient justification provided by the Swedish Academy of Sciences, responsible for the selection and election of the winners in this category. The word CRISPR (acronym for Clustered Regularly Interspaced Short Palindromic Repeats), described by the Spanish microbiologist at the University of Alicante, Francisco Juan Martínez Mojica, does not appear in the highlighted phrase of the award but, immediately, the whole world knew that this Nobel Prize in Chemistry was won by the "CRISPR", the famous gene editing tools, initially described by Mojica as elements of a complex and effective defense system in prokaryotes. And, thanks to the talent and vision of these two researchers, CRISPR were proposed to be used, out of context, for editing any gene of any living organism. In this review I will point out the key points that allowed Charpentier and Doudna to deserve this award and of course I will underline the role that many other researchers have played, including that of Mojica himself


Assuntos
Humanos , Congressos como Assunto , Prêmio Nobel , Química/história , Edição de Genes , Terapia Genética , Sistemas CRISPR-Cas , Espanha
11.
PLoS One ; 15(7): e0234612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726312

RESUMO

We aimed to assess whether Nobel prizes (widely considered the most prestigious award in science) are clustering in work done in a few specific disciplines. We mapped the key Nobel prize-related publication of each laureate awarded the Nobel Prize in Medicine, Physics, and Chemistry (1995-2017). These key papers mapped in only narrow sub-regions of a 91,726-cluster map of science created from 63 million Scopus-indexed published items. For each key Nobel paper, a median of 435 (range 0 to 88383) other Scopus-indexed items were published within one year and were more heavily cited than the Nobel paper. Of the 114 high-level domains that science can be divided into, only 36 have had a Nobel prize. Five of the 114 domains (particle physics [14%], cell biology [12.1%], atomic physics [10.9%], neuroscience [10.1%], molecular chemistry [5.3%]) have the lion's share, accounting in total for 52.4% of the Nobel prizes. Using a more granular classification with 849 sub-domains shows that only 71 of these sub-domains (8.3%) have at least one Nobel-related paper. Similar clustering was seen when we mapped all the 40,819 Scopus-indexed publications representing the career-long output of all the Nobel laureates. In conclusion, work resulting in Nobel prizes is concentrated in a small minority of scientific disciplines.


Assuntos
Prêmio Nobel , Ciência/história , Distinções e Prêmios , Bibliometria/história , Química/história , História da Medicina , História do Século XIX , História do Século XX , Humanos , Medicina , Física/história
12.
J Hist Biol ; 53(3): 451-484, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32524311

RESUMO

In 1869, Johann Friedrich Miescher discovered a new substance in the nucleus of living cells. The substance, which he called nuclein, is now known as DNA, yet both Miescher's name and his theoretical ideas about nuclein are all but forgotten. This paper traces the trajectory of Miescher's reception in the historiography of genetics. To his critics, Miescher was a "contaminator," whose preparations were impure. Modern historians portrayed him as a "confuser," whose misunderstandings delayed the development of molecular biology. Each of these portrayals reflects the disciplinary context in which Miescher's work was evaluated. Using archival sources to unearth Miescher's unpublished speculations-including an analogy between the hereditary material and language, and a speculation that a series of asymmetric carbon atoms could account for hereditary variation-this paper clarifies the ways in which the past was judged through the lens of contemporary concerns. It also shows how organization, structure, function, and information were already being considered when nuclein was first discovered nearly 150 years ago.


Assuntos
DNA/história , Genética/história , Historiografia , Biologia Molecular/história , Química/história , Cromatina/isolamento & purificação , DNA/isolamento & purificação , História do Século XIX , Humanos , Relações Interprofissionais , Supuração/história , Suíça
14.
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
16.
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
18.
Ann Sci ; 77(2): 155-168, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32419638

RESUMO

The Scottish Enlightenment has long been identified with abolitionism because of the writings of the moral and economic philosophers and the absence of slaves in Scotland itself. However, Scots were disproportionately represented in the ownership, management, and especially medical treatment of slaves in the British Caribbean. Sugar and cotton flowed into Glasgow and young, educated Scots looking for work as traders, bookkeepers, doctors made the return trip back to the Caribbean to manage the plantations. Chemically trained doctors and agriculturalists tested their theories in the plantations and developed new theories based on their experimentation on the land and slaves. In foregrounding the participation of Scottish trained chemists in the practice of slavery, I argue that the development of eighteenth-century chemistry and the broader intellectual Enlightenment were inextricably entangled with the economic Improvement Movement and the colonial economy of the British slave trade.


Assuntos
Química/história , Escravização/história , Região do Caribe , Colonialismo/história , História do Século XVIII , Escócia
19.
Ann Sci ; 77(2): 189-214, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32375567

RESUMO

From 1797 to 1801 a controversy played out on the pages of the Medical Repository, the first scientific journal published in the United States. At its centre was the well-known feud between the followers of Antoine Lavoisier and Joseph Priestley, the lone supporter of the phlogiston model. The American debate, however, had more than two sides. The Americans chemists, Samuel Latham Mitchill and Benjamin Woodhouse, who rushed to support Priestley did not defend his scientific views. Rather, as citizens of a republic, they defended his right to have them. They also castigated the assertions of the "French chemists," whose claims that the new chemistry obviated debate seemed unsettlingly similar to the dictatorial ambitions of the French state. Using the Medical Repository, Mitchill and Woodhouse sought a compromise that validated the new chemistry, but united it with a more egalitarian form of discourse. The desired balance eluded them. Priestley proved too stubborn, and as the French Revolution descended into dictatorship and war, Mitchill and Woodhouse came more to realize that truly prising French chemistry from the culture of the revolutionary era. The episode left Mitchill and Woodhouse disillusioned with chemistry and hoping to redirect scientific enthusiasm to more pious ends.


Assuntos
Química/história , Filosofia/história , Ciência/história , França , Revolução Francesa , História do Século XVIII , História do Século XIX , New York , Estados Unidos
20.
Ann Sci ; 77(2): 215-252, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32375584

RESUMO

Eighteenth-century events, replete with Dickensian dualities, brought two Enlightenment families to America. Pierre-Samuel du Pont and Joseph Priestley contemplated relocating their families decades before immigrating. After arriving, they discovered deficiencies in education and chemistry. Their experiences were indicative of the challenges in transmitting transatlantic chemistry. The Priestleys were primed to found an American chemical legacy. Science connected Priestley to British manufacturers, Continental chemists, and American statesmen. Priestley's marriage into the Wilkinson ironmaster dynasty, and Lunar Society membership, helped his sons apprentice, and befriend manufacturer-chemist Thomas Cooper. However, ideological persecution forced them from England. Priestley's plans for his sons to inherit Wilkinson's ironworks evaporated; in America, efforts to establish manufactories, colonies, farms, and a college miscarried. Cooper taught college chemistry, but his materialism provoked dismissals. The Du Ponts were unlikely founders of an industrial-chemistry empire. Du Pont's philosophy promulgated that agriculture, not industry, produced wealth. Eleuthère-Irénée apprenticed in France's gunpowder administration, however, plans for his succession died and director Antoine Lavoisier, a family friend, was executed. E.-I. and Du Pont's arrest precipitated relocation to America. Du Pont's utopian colony and schemes proved unrealistic. Nevertheless, E.-I.'s gunpowder manufactory-utilizing transatlantic contacts and privileged knowledge of advanced French chemistry-succeeded through practical application.


Assuntos
Química/história , França , História do Século XVIII , História do Século XIX , Reino Unido , Estados Unidos , Utopias/história
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