O tema cidadania na política brasileira de distribuição de livros didáticos de ciências

Neste trabalho apresentamos uma análise da categoria cidadania e ética presente no Programa Nacional do Livro Didático (PNLD), a política de avaliação e distribuição de livros didáticos do governo brasileiro para a educação pública. Para tanto, realizamos uma análise do conteúdo das questões propostas pelo programa, com base em modelos de cidadania científica disponíveis na literatura. Nossos resultados apontam para um predomínio do modelo procedimentalista na proposta de avaliação do programa, e para a valorização das virtudes de respeito à diversidade e da formação de uma opinião pública sobre a ciência

Carrapato e vermes: inimigos do gado e do produtor.

bitstream/item/65290/1/CT-95-Carrapato-e-vermes.pd

Anak Krakatau triggers volcanic freezer in the upper troposphere

Volcanic activity occurring in tropical moist atmospheres can promote deep convection and trigger volcanic thunderstorms. These phenomena, however, are rarely observed to last continuously for more than a day and so insights into the dynamics, microphysics and electrification processes are limited. Here we present a multidisciplinary study on an extreme case, where volcanically-triggered deep convection lasted for six days. We show that this unprecedented event was caused and sustained by phreatomagmatic activity at Anak Krakatau volcano, Indonesia during 22-28 December 2018. Our modelling suggests an ice mass flow rate of similar to 5x10(6)kg/s for the initial explosive eruption associated with a flank collapse. Following the flank collapse, a deep convective cloud column formed over the volcano and acted as a 'volcanic freezer' containing similar to 3x10(9)kg of ice on average with maxima reaching similar to 10(10)kg. Our satellite analyses reveal that the convective anvil cloud, reaching 16-18km above sea level, was ice-rich and ash-poor. Cloud-top temperatures hovered around -80 degrees C and ice particles produced in the anvil were notably small (effective radii similar to 20 mu m). Our analyses indicate that vigorous updrafts (>50m/s) and prodigious ice production explain the impressive number of lightning flashes (similar to 100,000) recorded near the volcano from 22 to 28 December 2018. Our results, together with the unique dataset we have compiled, show that lightning flash rates were strongly correlated (R=0.77) with satellite-derived plume heights for this event

Reaeration in Supercritical Open Channel Flows: An Experimental Study

Reaeration is a primary path of reoxygenation in streams, fundamental to environmental and ecological integrity. Previous laboratory studies of reaeration rates in subcritical flows showed large scatter in results, with differences in mass transfer coefficients of more than one order of magnitude between comparable flow conditions. Although supercritical flow is commonly observed in natural streams and engineered channels, systematic measurements of supercritical flow reaeration rates have been unavailable. Experiments in a laboratory open channel flume encompassing sub-and supercritical flows have been undertaken. The subcritical data were consistent with a large body of previous studies. Supercritical flows showed 6-10 times stronger reaeration rates than comparable subcritical conditions, while local rates at hydraulic jumps systematically exceed those in the supercritical flows upstream by a factor up to three. A close relationship between reaeration rates and turbulent dissipation rate is observed, and a systematic Froude number dependency is demonstrated for both sub-and supercritical flows. Observed mass transfer coefficients do not correlate as well with flow Reynolds number and shear Reynolds number. The higher reaeration rates associated with supercritical flows indicates that a change in open channel flow regime for the same Reynolds number may be used to improve water quality

Traumatic brain injury and NADPH oxidase: A deep relationship

Traumatic brain injury (TBI) represents one of the major causes of mortality and disability in the world. TBI is characterized by primary damage resulting from the mechanical forces applied to the head as a direct result of the trauma and by the subsequent secondary injury due to a complex cascade of biochemical events that eventually lead to neuronal cell death. Oxidative stress plays a pivotal role in the genesis of the delayed harmful effects contributing to permanent damage. NADPH oxidases (Nox), ubiquitary membrane multisubunit enzymes whose unique function is the production of reactive oxygen species (ROS), have been shown to be a major source of ROS in the brain and to be involved in several neurological diseases. Emerging evidence demonstrates that Nox is upregulated after TBI, suggesting Nox critical role in the onset and development of this pathology. In this review, we summarize the current evidence about the role of Nox enzymes in the pathophysiology of TBI

Influence of extraction process on the luminescent properties of carbon nanomaterials derived from olive mill wastewaters

Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2016 do Instituto Politécnico de Lisboa. Código de referência IPL/2016/NANOLIVE/ISELIn an accompanying communication [1], we have revealed that nanosized carbon materials could be easily obtained from olive mil wastewater (OMWW) using green, sustainable and simple technological processes. In this contribution we will essentially focus on the study of the impact of the effluent nature on the structural, morphological and luminescente characteristics of synthesized carbon nanodots (CNDs).info:eu-repo/semantics/publishedVersio

Do’s and don’ts of microplastic research: a comprehensive guide

Microplastics are environmental contaminants consisting of small plastics ≤ 5 mm. Concerns over the adverse effects of microplastics have led to a rapid growth in the available literature despite the lack of harmonized methods and materials. Therefore, the field is becoming increasingly daunting to new researchers. A state-of-theart guide was assembled following a comprehensive literature review of microplastics research with the intent of addressing contemporary challenges, prioritized based on a survey, and introducing best practices. The lack of standardized methods and reference materials, the lack of access to analytical equipment, and the difficulty in working with lower environmental concentrations in laboratory tests (e.g., toxicity assays) remain a great challenge. The present work addresses these issues across three main sections: definitions, sampling, and evaluation of adverse effects. Harmonized methods and greater collaboration were identified as opportunities in this rapidly evolving field. A review of available interlaboratory comparison tests was also conducted to support additional recommendations.Padrão J would like to acknowledge the funding by the Portuguese Foundation for Science and Technology (FCT), European Regional Development Fund (FEDER), Operational Program for Competitiveness Factors (COMPETE), and Portuguese Ministry of Science, Technology and Higher Education (MCTS): [UID/CTM/00264/2021]

Time of flight detectors with SiPMT array readout

none6noTime-of-flight detectors, based on scintillation counters, may use conventional photomultipliers for the readout. Problems arise in presence of external magnetic fields. SiPMT arrays are insensitive to magnetic fields and may be a suitable option to replace photomultipliers. Timing performances for several types of SiPMT arrays have been studied and results are presented.Bonesini, M; Bertoni, R.; de Bari, A.; Nardò, R.; Prata, M.; Rossella, M.Bonesini, M; Bertoni, R.; DE BARI, Antonio; Nardo', Roberto; Prata, M.; Rossella, M