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This study analyzes factors of sexual harassment in the workplace based on sample survey data on women working in the Korean film industry (n = 449) using logistic regression analysis. It finds higher education, younger age, and union membership increase harassment risk, suggesting backlash against feminism post-#MeToo. A higher proportion of men at shooting locations raises harassment likelihood, reflecting the industry's unique conditions. Longer work hours also increase harassment probability. The findings highlight the importance of considering industrial context in addressing workplace harassment. They emphasize the need for policies improving gender representation in film.
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BACKGROUND: Traditional medicines based on herbal extracts have been proposed as affordable treatments for patients suffering from coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Teas and drinks containing extracts of Artemisia annua and Artemisia afra have been widely used in Africa in efforts to prevent SARS-CoV-2 infection and fight COVID-19. METHODS: The plant extracts and Covid-Organics drink produced in Madagascar were tested for plaque reduction using both feline coronavirus and SARS-CoV-2 in vitro. Their cytotoxicities were also investigated. RESULTS: Several extracts as well as Covid-Organics inhibited SARS-CoV-2 and FCoV infection at concentrations that did not affect cell viability. CONCLUSIONS: Some plant extracts show inhibitory activity against FCoV and SARS-CoV-2. However, it remains unclear whether peak plasma concentrations in humans can reach levels needed to inhibit viral infection following consumption of teas or Covid-Organics. Clinical studies are required to evaluate the utility of these drinks for COVID-19 prevention or treatment of patients.
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Antivirais/farmacologia , Artemisia/química , Extratos Vegetais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Coronavirus Felino/efeitos dos fármacos , Coronavirus Felino/crescimento & desenvolvimento , Extratos Vegetais/química , SARS-CoV-2/crescimento & desenvolvimento , Ensaio de Placa ViralRESUMO
It has been reported that fragments produced by glycosidic bond breakage in mass spectrometry-based experiments can retain a memory of their anomeric configuration, which has major implications for glycan sequencing. Herein, we use cryogenic vibrational spectroscopy and ion mobility-mass spectrometry to study the structure of B-type fragments of protected galactosides. Cationic fragments were generated from glycosyl donors carrying trichloroacetimidate or thioethyl leaving groups of different anomeric configuration. The obtained infrared signatures indicate that the investigated fragments exhibit an identical structure, which suggests that there is no anomeric memory in B-type ions of fully protected monosaccharides.
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The stereoselective formation of 1,2-cis-glycosidic bonds is challenging. However, 1,2-cis-selectivity can be induced by remote participation of C4 or C6 ester groups. Reactions involving remote participation are believed to proceed via a key ionic intermediate, the glycosyl cation. Although mechanistic pathways were postulated many years ago, the structure of the reaction intermediates remained elusive owing to their short-lived nature. Herein, we unravel the structure of glycosyl cations involved in remote participation reactions via cryogenic vibrational spectroscopy and first principles theory. Acetyl groups at C4 ensure α-selective galactosylations by forming a covalent bond to the anomeric carbon in dioxolenium-type ions. Unexpectedly, also benzyl ether protecting groups can engage in remote participation and promote the stereoselective formation of 1,2-cis-glycosidic bonds.
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Predicting the stereochemical outcome of chemical reactions is challenging in mechanistically ambiguous transformations. The stereoselectivity of glycosylation reactions is influenced by at least eleven factors across four chemical participants and temperature. A random forest algorithm was trained using a highly reproducible, concise dataset to accurately predict the stereoselective outcome of glycosylations. The steric and electronic contributions of all chemical reagents and solvents were quantified by quantum mechanical calculations. The trained model accurately predicts stereoselectivities for unseen nucleophiles, electrophiles, acid catalyst, and solvents across a wide temperature range (overall root mean square error 6.8%). All predictions were validated experimentally on a standardized microreactor platform. The model helped to identify novel ways to control glycosylation stereoselectivity and accurately predicts previously unknown means of stereocontrol. By quantifying the degree of influence of each variable, we begin to gain a better general understanding of the transformation, for example that environmental factors influence the stereoselectivity of glycosylations more than the coupling partners in this area of chemical space.
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Reliable glycosylation reactions that allow for the stereo- and regioselective installation of glycosidic linkages are paramount to the chemical synthesis of glycan chains. The stereoselectivity of glycosylations is exceedingly difficult to control due to the reaction's high degree of sensitivity and its shifting, simultaneous mechanistic pathways that are controlled by variables of unknown degree of influence, dominance, or interdependency. An automated platform was devised to quickly, reproducibly, and systematically screen glycosylations and thereby address this fundamental problem. Thirteen variables were investigated in as isolated a manner as possible, to identify and quantify inherent preferences of electrophilic glycosylating agents (glycosyl donors) and nucleophiles (glycosyl acceptors). Ways to enhance, suppress, or even override these preferences using judicious environmental conditions were discovered. Glycosylations involving two specific partners can be tuned to produce either 11:1 selectivity of one stereoisomer or 9:1 of the other by merely changing the reaction conditions.
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A mild and efficient synthesis of N-arylcarbamates was achieved by reacting azidoformates with boronic acids in the presence of 10 mol % of copper chloride catalyst. The reaction proceeds readily in an open flask at room temperature without additional base, ligand, or additive. Rapid access to urea analogues via a two-step one-pot procedure is enabled by reacting N-arylcarbamates with aluminum-amine complexes. In addition, among several boronic acid derivatives prepared, dimethylphenyl boronate was found to react rapidly in its reaction with benzyl azidoformate, invoking in situ generation of this species in the catalytic cycle.
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Azidas/química , Ácidos Borônicos/química , Carbamatos/síntese química , Cobre/química , Carbamatos/química , Catálise , Ligantes , Estrutura Molecular , TemperaturaRESUMO
A mild and efficient method for the synthesis of N-arylsulfonamides in the presence of 10 mol % of CuCl is demonstrated. The reaction proceeds readily at room temperature in an open flask using a variety of sulfonyl azides and boronic acids without any base, ligand, or additive.
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Azidas/química , Ácidos Borônicos/química , Cobre/química , Sulfonamidas/química , Sulfonamidas/síntese química , Catálise , Técnicas de Química Combinatória , Estrutura Molecular , TemperaturaRESUMO
The present study investigated the effect of transverse vibration on the hemo-rheological characteristics of blood flow using a newly designed pressure-scanning capillary viscometer. As a transverse vibration was applied, aggregated blood cells become disaggregated. Frequency of vibration was found to be the main parameter causing hemo-rheological changes. For RBC suspension in a non-aggregating medium (Dextran 40), increasing frequency of vibration caused decreased flow resistance. Meanwhile, flow resistance for whole blood increased with frequency of vibration. These seemingly contradictory results could be interpreted without conflict when a comprehensive mechanism of cell migration under vibration is elucidated. The present study confirmed that vibration diminishes RBC aggregation, which triggers two different cell migration mechanisms and subsequently resulted in either increasing or decreasing the flow resistance.