Doação de sangue durante a pandemia da Covid-19: conhecimentos, práticas e atitudes dos estudantes de medicina / Blood donation during the Covid-19 pandemic: knowledge, practices and attitudes of medical students

Doação voluntária de sangue é um ato desafiador, em especial, durante períodos de crise sanitária. O propósito deste estudo transversal foi analisar os conhecimentos, práticas e atitudes dos estudantes de medicina, do ciclo básico ao internato, quanto à doação de sangue durante a pandemia da Covid-19. O trabalho foi realizado entre maio e dezembro de 2021, via Google forms. Para motivo de comparação, a amostra (n=327) foi dividida em do-adores (n=183) e não doadores (n=144) de sangue e utilizado teste qui-quadrado e teste exato de Fisher, sendo considerado estatisticamente significantes perguntas que obtiveram valores com p<0,05. Os resultados indicam que, mesmo sendo a minoria de ambos os grupos, ainda há uma quantidade significativa de estudantes de medicina que apresentam pouco domínio sobre o processo de doação de sangue, além de estarem permeados por medo e desinformação sobre a segurança da coleta. Fatos estes, ainda mais perceptíveis durante o período da pandemia, no qual o percentual de doadores foi de 30,6%. Desta forma, ressalta-se a necessidade de estratégias educacionais criativas e contextualizadas para esclarecer e sensibilizar melhor os jovens para este ato de solidariedade (AU).

Voluntary blood donation is a challenging act, especially during a health crisis. The purpose of this cross-sectional study was to analyze the knowledge, practices, and attitudes of medical students, from the basic cycle to the internship, regarding blood donation during the Covid-19 pandemic. The work was carried out between May and December 2021 via Google Forms. For comparison, the sample (n=327) was divided into blood donors (n=183) and non-donors (n=144). The chi-square and Fisher's exact tests were used, considering statistically significant questions with p<0.05 p-value. The results indicate that, even though they are a minority of both groups, there is still a significant number of medical students who do not know much about the blood donation process and are permeated by fear and misinformation about blood collection safety. These facts were even more noticeable during the pandemic, in which the percentage of donors was 30.6%. In this way, the need for creative and contextualized educational strategies is highlighted to clarify and better sensitize young people to this act of solidarity (AU).

Where do leaf water leaks come from? Trade-offs underlying the variability in minimum conductance across tropical savanna species with contrasting growth strategies.

Plants continue to lose water from their leaves even after complete stomatal closure. Although this minimum conductance (gleaf-res ) has substantial impacts on strategies of water use and conservation, little is known about the potential drivers underlying the variability of this trait across species. We thus untangled the relative contribution of water leaks from the cuticle and stomata in order to investigate how the variability in leaf morphological and anatomical traits is related to the variation in gleaf-res and carbon assimilation capacity across 30 diverse species from the Brazilian Cerrado. In addition to cuticle permeance, water leaks from stomata had a significant impact on gleaf-res . The differential pattern of stomata distribution in the epidermis was a key factor driving this variation, suggesting the existence of a trade-off between carbon assimilation and water loss through gleaf-res . For instance, higher gleaf-res , observed in fast-growing species, was associated with the investment in small and numerous stomata, which allowed higher carbon assimilation rates but also increased water leaks, with negative impacts on leaf survival under drought. Variation in cuticle structural properties was not linked to gleaf-res . Our results therefore suggest the existence of a trade-off between carbon assimilation efficiency and dehydration tolerance at foliar level.

Anthropogenic litter on Brazilian beaches: Baseline, trends and recommendations for future approaches.

Beaches are fundamental habitats that regulate the functioning of several coastal processes and key areas contributing to national and local budgets. In this study we provide the first large-scale systematic survey of anthropogenic litter on Brazilian beaches, covering a total of 35 degrees of latitude, recording the litter type, its use and size. Plastic comprised the most abundant litter type, followed by cigarette butts and paper. Small pieces (<5 cm) were dominant among litter size-classes and food-related use was associated to most litter recorded types. Generalized additive models showed that proximity to estuarine run-offs was the main driver to beach litter accumulation, reinforcing river drainages as the primary route of litter coastal pollution. Also, the Clean-Coast Index evidenced there was not a pattern of beach litter pollution among regions, which denotes that actions regarding marine pollution must be taken by all state governances of the country.