Aplicação da Calorimetria Exploratória Diferencial (DSC) para Determinação da Pureza de Fármacos

O trabalho aborda um estudo comparativo entre a técnica de Cromatografia a Líquido de Alta Eficiência e a técnica de Calorimetria Exploratória Diferencial, visando avaliar a aplicação desta para a determinação direta da pureza de fármacos candidatos a materiais de referência certificados

Avaliação de laboratórios brasileiros na determinação de alguns parâmetros de qualidade de biocombustíveis

This work shows the results of a Proficiency Testing performed by a partnership between INMETRO and ANP. The performance of 49 Brazilian laboratories (using the z-score statistical test) in determining 10 quality parameters of ethanol fuel and biodiesel was evaluated. The certified reference values were provided by INMETRO, allowing a more rigorous assessment of the laboratories. For hydrous ethanol, the acidity parameter showed the lowest number of laboratories with satisfactory results (48%), while 85% of the laboratories presented satisfactory results for ethanol content. For biodiesel, the percentage of laboratories with satisfactory results ranged from 46% (kinematic viscosity) to 92% (acid number)

Ansiedade dos estudantes diante da expectativa do exame vestibular

Este estudio investigó la ansiedad de los estudiantes en las escuelas privadas en un estado de Brasil en el examen de ingreso. La muestra fuese compuesta de 124 estudiantes de la escuela secundaria participantes del PISM (Proceso de Admisión Común), siendo 66 mujeres e 58 hombres, 69 alumnos del 1er año de escuela secundaria y 55 del 3er año. Los estudiantes respondieron a un cuestionario socio-demográfico y al Inventario de Ansiedad Rasgo-Estado (IDATE), en sus propias aulas. Hubo una diferencia significativa en relación con el género (p=0,036) que se encontró un mayor nivel de ansiedad estado en el 1er año de las mujeres en comparación con los hombres del 1er año (p = 0,004). El mismo resultado se encontró con respecto a la ansiedad-rasgo: las mujeres de 1er año son más ansiosas que los hombres del 1er año (p=0,000).O presente estudo investigou a ansiedade dos jovens estudantes de escolas particulares de um estado do Brasil em relação ao exame vestibular. A amostra foi composta por 124 estudantes do ensino médio participantes do vestibular seriado PISM (Processo de Ingresso Seletivo Misto), sendo 66 do gênero feminino e 58 do gênero masculino, 69 alunos do 1º ano do ensino médio e 55 do 3º ano. Os estudantes responderam a um questionário sócio-demográfico e ao Inventário de Ansiedade Traço-Estado (IDATE) na suas próprias salas de aula. Foi observada uma diferença significativa quanto ao gênero (p=0,036) sendo que foi encontrado um maior nível de ansiedade-estado nas mulheres do 1º ano comparativamente aos rapazes do 1ºano (p=0,004). O mesmo resultado foi encontrado com relação à ansiedade-traço: moças do 1º ano são mais ansiosas do que rapazes do 1º ano (p=0,000).This study investigated the anxiety of private schools students at the expectation of attending colleges' entrance examination in one Brazilian state. The sample consisted of 124 high school students participating in the PISM series of examination (Joint Selective Admission Process). They were 66 females and 58 males, 69 students from the 1st year and 55 from the 3rd year. Students answered a sociodemographic questionnaire and the State-Trait Anxiety Inventory in their respective classrooms. A significant difference regarding gender (p=0.036) was found, women from the 1st year presented higher levels of state-anxiety compared to men from the 1st year (p=0.004). The same result was found with respect to the trait-anxiety, women from the 1st year were more anxious than men from the 1st year (p=0.000)

Local hydrological conditions influence tree diversity and composition across the Amazon basin

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio