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1.
Nat Chem Biol ; 18(5): 438-439, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35301480
2.
JAMA ; 327(11): 1095, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35289888
4.
Regul Toxicol Pharmacol ; 128: 105093, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34864125

RESUMO

The European Commission's Green Deal is a major policy initiative aiming to achieve a climate-neutral, zero-pollution, sustainable, circular and inclusive economy, driving both the New Industrial Strategy for Europe and the Chemicals Strategy for Sustainability. Innovative materials can help to reach these policy goals, but they need to be safe and sustainable themselves. Thus, one aim is to shift the development of chemicals to Safe- and Sustainable-by-Design, and define a new systems approach and criteria for sustainability to achieve this. An online workshop was organised in September 2020 by the Joint Research Centre and the Directorate-General Research and Innovation of the European Commission, with participants from academia, non-governmental organisations, industry and regulatory bodies. The aims were to introduce the concept of Safe- and Sustainable-by-Design, to identify industrial and regulatory challenges in achieving safer and more sustainable Smart Nanomaterials as an example of innovative materials, and to deliver recommendations for directions and actions necessary to meet these challenges. The following needs were identified: (i) an agreed terminology, (ii) a common understanding of the principles of Safe- and Sustainable-by-Design, iii) criteria, assessment tools and incentives to achieve a transition from Safe-by-Design to Safe- and Sustainable-by-Design, and (iv) preparedness of regulators and legislation for innovative chemicals/nanomaterials. This paper presents the authors' view on the state of the art as well as the needs for future activities, based on discussions at the workshop and further considerations. The case of Smart Nanomaterials is used to illustrate the Safe- and Sustainable-by-Design concept and challenges for its implementation. Most of the considerations can be extended to other advanced materials and to chemicals and products in general.


Assuntos
Química/normas , Meio Ambiente , Regulamentação Governamental , Nanoestruturas/química , Nanotecnologia/organização & administração , Desenvolvimento Sustentável/tendências , União Europeia , Humanos , Nanotecnologia/normas , Políticas
5.
Chem Asian J ; 17(4): e202101219, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-34942037

RESUMO

ESIPT active PBI-keto/enol assemblies have been developed which show 'on-on' optical response towards 2,6-dichloro-4-nitroaniline (DCN) due to a combined ESIPT-AIEE phenomenon with a detection limit of 1.65 nM. The potential of PBI-keto/enol assemblies to detect DCN has also been explored in grape juice/grape residue and soil for six consecutive days. Further, the biological applications of PBI-keto/enol assemblies to detect DCN in blood serum, in MG-63 cell lines and their ability to restrict the DCN-induced cell death have been demonstrated.


Assuntos
Química , Compostos de Anilina
6.
Acta Chim Slov ; 68(4): 1016-1026, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34918761

RESUMO

Studies on students' problem-solving skills worldwide suggest there is a room for improvement. This study aimed at improving upper-secondary school students' problem-solving skills in chemistry lessons. They were given a problem tasks pre-test focused on their conceptual knowledge regarding the periodic table, ability to apply knowledge on the factors affecting chemistry reaction rate and compounds' properties. Most students (72 out of 112) did not succeed to solve the tasks. For this reason, an intervention was designed based on a study using eye-tracking combined with think-aloud. It consisted of students' working on (PISA-like) context-based chemistry problem tasks with a special scaffolding. A teacher provided formative assessment promoting students' expansive strategies. The intervention's effect was again assessed using problem tasks in two post-tests. The results showed the action plan was successful in helping the majority of students reach above-average test score. The ratio of successful solvers also rose and unsuccessful significantly declined.


Assuntos
Aprendizagem , Estudantes/psicologia , Química/educação , Tecnologia de Rastreamento Ocular , Humanos , Resolução de Problemas , Instituições Acadêmicas
8.
Chem Rec ; 21(11): 2928-2929, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34766718
10.
J Chem Inf Model ; 61(11): 5305-5306, 2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34668709
13.
ACS Chem Biol ; 16(11): 2042-2046, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34523912

RESUMO

Despite decades of progress toward a more equitable society, gender representation in the sciences continues to be heavily skewed toward men. We were interested in gender representation in chemistry through the lens of scientific publishing. Publications are a central academic currency and are critical for funding, recruiting, and promotion in academia. Here we report the results of an analysis that compared the percentage of female first and last authors across 10 chemistry, 3 chemical biology, and 3 general journals from 2005 to 2020. We show that women are substantially underrepresented in chemistry authorship even when compared with their relative populations in academia and are not predicted to achieve parity within the next 50 years at the current rate in any journal. Our findings highlight the need for changes to the publishing process to achieve a more equitable publishing environment.


Assuntos
Autoria , Química/estatística & dados numéricos , Publicações Seriadas/estatística & dados numéricos , Química/organização & administração , Feminino , Equidade de Gênero , Humanos , Masculino , Editoração/organização & administração , Distribuição por Sexo
14.
Ciênc. cogn ; 26(1): 66-76, 10 set. 2021. ilus
Artigo em Português | LILACS | ID: biblio-1292983

RESUMO

O objetivo deste estudo interdisciplinar foi usar curtas metragens produzidos por estudantes do ensino médio sobre temas da Química para o ensino de Sociologia. Neste sentido, foram produzidos mapas conceituais pelos estudantes, após a discussão dos curtas metragens, sob uma perspectiva sociológica. Nossos resultados mostram que os mapas conceituais podem atuar como instrumentos facilitadores para a aprendizagem, capazes de estimular a pesquisa e promover a autonomia dos estudantes durante o processo de construção do conhecimento.


The aimof this interdisciplinary study was useshort films produced by high school students about chemical themes to Sociology teaching. In this way, conceptual maps were constructedby students after short films discussion under a social perspective. Our results showed that conceptual maps could act as facilitating learning instrument, able to stimulate research and to promote student autonomy during the knowledge construction process.


Assuntos
Humanos , Adolescente , Ensino , Ensino Fundamental e Médio , Sociologia , Estudantes , Química
15.
Chimia (Aarau) ; 75(5): 442, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34016241
16.
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
COVID-19 , Química/educação , Educação à Distância , COVID-19/epidemiologia , Química Farmacêutica/educação , Currículo , Educação em Farmácia/métodos , Humanos , Nova Zelândia/epidemiologia , Pandemias , SARS-CoV-2 , Universidades
17.
Biochem Mol Biol Educ ; 49(4): 619-624, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33913586

RESUMO

Every branch of science needs visitors' attention during the poster presentation session at conferences, symposiums, seminars, etc. In particular, participants in the chemistry and biochemistry conference need more visual tools to explain their research work in detail. Presence of smartphones and the ability of 2D barcodes will allow chemical reactions or processes to be shown in the form of a movie, animation or augmented reality (AR). Therefore, the next generation of posters will be more interested in this view. Here, the ability of 2D barcodes or QR codes to help researchers to catch more attention in their research work was presented during a poster presentation session. In this way, the visitors showed positive attitudes to the applicability of such tools. Also, some information including the number of poster visitors and interesting topics in the conference can be collected easily which is useful for the scientific and organizing committee of conferences. As a result, biochemistry conference posters can be presented in new ways, based on animation images or video, to capture the attention of viewers and deepen their understanding of poster concepts.


Assuntos
Recursos Audiovisuais/estatística & dados numéricos , Realidade Aumentada , Bioquímica/educação , Química/educação , Comunicação , Disseminação de Informação/métodos , Gravação em Vídeo/métodos , Congressos como Assunto , Humanos , Pôsteres como Assunto
18.
Ann Sci ; 78(2): 221-245, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33888042

RESUMO

Between 1920 and 1922, the University of Bristol biochemist, Maximilian Nierenstein, published four papers in a series exploring the structure of catechin in the Journal of the Chemical Society. The Society then abruptly refused to accept any more of his papers on catechin, or any other subject. It provided him with no reasons for the embargo until 1925. It then transpired that Nierenstein was boycotted because it was deemed that he had not responded adequately to criticisms of his work made by his rival in catechin research, the German natural products chemist, Karl Freudenberg. It was not until 1929 that, as a result of a petition by a group of his former Bristol pupils and friends, that Nierenstein was again permitted to publish in the Society's journal. The paper explores the Chemical Society's treatment of Nierenstein in detail, sheds new light on his career and his reaction to the Society's unprecedented boycott, examines some of the structural chemistry involved in the disputes, and discusses whether Nierenstein's research deserves the label of 'bad science'.


Assuntos
Catequina/história , Química/história , Pesquisadores/história , Sociedades Científicas/história , Catequina/química , Inglaterra , História do Século XX , Pesquisadores/normas
19.
Pharmacol Ther ; 225: 107837, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33753133

RESUMO

Vaping is the process of inhaling and exhaling an aerosol produced by an e-cigarette, vape pen, or personal aerosolizer. When the device contains nicotine, the Food and Drug Administration (FDA) lists the product as an electronic nicotine delivery system or ENDS device. Similar electronic devices can be used to vape cannabis extracts. Over the past decade, the vaping market has increased exponentially, raising health concerns over the number of people exposed and a nationwide outbreak of cases of severe, sometimes fatal, lung dysfunction that arose suddenly in otherwise healthy individuals. In this review, we discuss the various vaping technologies, which are remarkably diverse, and summarize the use prevalence in the U.S. over time by youths and adults. We examine the complex chemistry of vape carrier solvents, flavoring chemicals, and transformation products. We review the health effects from epidemiological and laboratory studies and, finally, discuss the proposed mechanisms underlying some of these health effects. We conclude that since much of the research in this area is recent and vaping technologies are dynamic, our understanding of the health effects is insufficient. With the rapid growth of ENDS use, consumers and regulatory bodies need a better understanding of constituent-dependent toxicity to guide product use and regulatory decisions.


Assuntos
Vaping , Química , Humanos , Toxicologia , Vaping/efeitos adversos
20.
Int J Mol Sci ; 22(3)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535426

RESUMO

The free volume fraction of a macromolecular structure can be assessed theoretically by using a suitable model; however, it can also be evaluated from experimental data obtained from dilatometry and positron annihilation lifetime spectra. In this second case, a regular geometry of the sub-nanometric cavities forming the free volume has to be assumed, although in fact they are irregularly shaped. The most popular approach is to guess spherical holes, which implies an isotropic growth of these last with temperature. In this work, we compared the free volume fraction, as obtained from experiments in a set of polybutadiene and polyisoprene cured rubbers and their blends, with the analogous quantity expected by using the lattice-hole model. The results allowed us to obtain insights on the approximate shape of the holes. Indeed, a cylindrical flattened geometry of the cavities produced a better agreement with the theory than the spherical shape. Furthermore, the best fit was obtained for holes that expanded preferentially in the radial direction, with a consequent decrease of the aspect ratio with temperature.


Assuntos
Butadienos/química , Química/métodos , Elastômeros/química , Hemiterpenos/química , Borracha/química , Teste de Materiais , Estrutura Molecular , Pressão , Temperatura , Termodinâmica
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