Molecular fluid flow in MoS2 nanoporous membranes and hydrodynamics interactions

We study the impact of the induced pressure fields on the water flow and salt rejection in nanopores produced in MoS2 membranes. We observe that the water permeability and the salt rejection are not impacted by the distance between the pores. This result contradicts the continuous fluid mechanics calculations in microfilters, which indicates the existence of hydrodynamic interactions between adjacent pores that increase the water mobility. Our results suggest that at this nanoscale, the hydrodynamic interactions do not affect the water mobility through nanopores

Structure and mobility of water confined in AlPO4-54 nanotubes

We performed molecular dynamics simulations of water confined within AlPO4-54 nanotubes. AlPO4-54 is an artificial material made of AlO4 and of PO4 in tetrahedra arranged in a periodic structure forming pores of approximately 1.3 nm in diameter. This makes AlPO4-54 an excellent candidate for practical applications, such as for water filtration and desalination. In this work, the structural and dynamical properties of the confined water are analyzed for various temperatures and water loadings. We find that the water structure is controlled by the heterogeneity of the nanopore surface with the water molecules located preferentially next to the surface of oxygens of AlPO4-54; consequently, at very low densities, water forms helicoidal structures in string-like arrangements

Guidelines to sign Read and Publish agreements in Brazil from the analysis of the transformative agreements of Germany and Colombia

A democratização no acesso à ciência almejada com o Acesso Aberto vem acompanhada do pagamento de Article Processing Charges. Em um contexto de escassez de recursos financeiros, “pagar para publicar” se torna um desafio para países em desenvolvimento como o Brasil. Dada a inexistência de uma política sobre financiamento dessa despesa para as agências de fomento brasileiras e a proliferação de acordos transformativos ao redor do mundo, este artigo apresenta diretrizes para implantar acordos Read and Publish na Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, a partir da análise dos acordos firmados na Alemanha e Colômbia. Entre as diretrizes propostas, sugere-se que os acordos alcancem periódicos de Acesso Aberto e híbridos, considerem o histórico de publicações dos programas de pós-graduação para distribuição de recursos com vistas a financiar Article Processing Charges e funcionem como uma política de qualificação que auxilie os pesquisadores brasileiros a publicar em revistas de alto impacto.The democratization of access to science sought with Open Access is accompanied by the payment of Article Processing Charges. In a context of scarce financial resources, “pay to publish” becomes a challenge for developing countries like Brazil. Given the lack of a policy on financing the charges for Brazilian funding agencies and the proliferation of transformative agreements around the world, this article presents guidelines for implementing Read and Publish agreements at Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, based on the analysis of agreements signed in Germany and Colombia. Among the proposed guidelines, it is suggested that the agreements cover Open Access and hybrid journals, consider the publication history of postgraduate programs for the distribution of resources aiming to finance Article Processing Charges and function as a qualification policy that helps Brazilian researchers to publish in high impact journals

Anomalias dinâmicas de fluidos com potenciais com dois alcances

33

Special issue on soft matter research in Latin America

Resumo não disponíve

Emmy Nöther’s Theorem, 100 years : allegory of the misogyny in science

O teorema de Nöther é revisitado com dois objetivos: ressaltar a significado desses resultados para a física contemporânea e ao mesmo tempo apresentar aspectos da biografia de Emmy Nöther, enfatizando a misoginia sofrida na sua atividade científica, a despeito da reconhecida importância, ainda em vida, de seus trabalhos. Sob esta perspectiva, a vida de Emmy Nöther levanta a questão sobre a situação atual da atuação da mulher em ciência. Esse aspecto é abordado através de uma análise da participação de mulheres atuando em ciências com dados do CNPq e da CAPES. Para discutir e apresentar a dimensão apropriada dos resultados principais de Emmy Nöther, contextualizando a importância na física contemporânea, um caminho algébrico é seguido (nos livros textos, os teoremas são apresentados através do formalismo Lagrangiano), mas tanto quanto possível procurando uma abordagem discurso pedagógica.The Nöther's theorem is revisited with two main goals: to reinforce the meaning of such results for the contemporary physics and to present aspects of the Nöther's biography emphasizing the misogyny process that she suffered during her scientific life, despite of the recognized importance of her results even when she was alive. Under this perspective, the Nöther's live raises questions about the present-day participation of women in science. This aspect is addressed by an analysis of female researchers, by using data from CNPq and CAPES (two Brazilian Government agencies). In order to discuss and to present a proper dimension of the Nöther results, emphasizing such results for physics, an algebraic way is followed (usually such results are derived through the Lagrangian formalism); however, as much as possible, looking for a pedagogical presentation

Effects of confinement on anomalies and phase transitions of core-softened fluids

We use molecular dynamics simulations to study how the confinement affects the dynamic, thermodynamic, and structural properties of a confined anomalous fluid. The fluid is modeled using an effective pair potential derived from the ST4 atomistic model for water. This system exhibits density, structural, and dynamical anomalies, and the vapor-liquid and liquid-liquid critical points similar to the quantities observed in bulk water. The confinement is modeled both by smooth and structured walls. The temperatures of extreme density and diffusion for the confined fluid show a shift to lower values while the pressures move to higher amounts for both smooth and structured confinements. In the case of smooth walls, the critical points and the limit between fluid and amorphous phases show a non-monotonic change in the temperatures and pressures when the nanopore size is increase. In the case of structured walls, the pressures and temperatures of the critical points varies monotonically with the pore size. Our results are explained on basis of the competition between the different length scales of the fluid and the wall-fluid interaction

Liquid crystal phase and waterlike anomalies in a core-softened shoulder-dumbbells system

Using molecular dynamics we investigate the thermodynamics, dynamics and structure of 250 diatomic molecules interacting by a core-softened potential. This system exhibits thermodynamics, dynamics and structural anomalies: a maximum in density-temperature plane at constante pressure and maximum and minimum points in the diffusivity and translational order parameter against density at constant temperature. Starting with very dense systems and decreasing density the mobility at low temperatures first increases, reach a maximum, then decreases, reach a minimum and finally increases. In the pressure-temperature phase diagram the line of maximum translational order parameter is located outside the line of diffusivity extrema that is enclosing the temperature of maximum density line. We compare our results with the monomeric system showing that the anisotropy due to the dumbbell leads to a much larger solid phase and to the appearance of a liquid crystal phase. the double ranged thermodynamic and dynamic anomalies.Comment: 14 pages, 5 figure

Prescribed enteral diet versus infused diet

Objective: To evaluate the prescribed volume of enteral feeding versus the volume infused, identifying the diet for interruption, and expenses generated by these interruptions. Methods: Observational study with adults and elderly patients receiving enteral nutrition in a private hospital in São Paulo. Data collection was performed by means of electronic medical records. Results: The infused volume was significantly lower than the amount prescribed in the five days of monitoring in the entire sample. The main complication in the experimental diet was diarrhea. Spending on non-diet administration amount to 41.4% of the amount spent for this service. Conclusion: This study contributes to the performance and nutritionist performance in conjunction with the multidisciplinary team in Nutrition Therapy aiming at the improvement of the patient

Fotodiagnóstico como ferramenta metodológica em Educação Ambiental

The new generation continues to be driven by imaging records anywhere at any time, thanks to advanced technology that allows us to see the world and situations in a variety of ways and in rich detail, which enabled the various photo-related researches to create methods such as photoelectricity, iconography, ecnography, among others. In this research, the photodiagnosis was used to sensitize individuals to the impacts of solid waste in a mangrove area. In this sense, this article aims to present the results of the implementation of photodiagnosis as a tool in Environmental Education. The methodological approach adopted has a qualitative character and was constituted in two distinct and consecutive stages. Interpretive analysis was used, one of the steps that make up content analysis, and data collection, which occurred through a focus group. The results of the research demonstrated that photography can be a great methodological tool allied to the processes of sensitization in environmental education for a change of behavior through the reflection of the images by its participants.La nueva generación continúa impulsada por los registros de imágenes en cualquier lugar y en cualquier momento, gracias a la tecnología avanzada que nos permite ver el mundo y las situaciones de diversas maneras y con gran detalle, lo que permitió a las diversas investigaciones relacionadas con la fotografía crear métodos como fotoelectricidad, iconografía, ecnografía, entre otros. En esta investigación, el fotodiagnóstico se utilizó para sensibilizar a las personas sobre los impactos de los desechos sólidos en un área de manglares. En este sentido, este artículo tiene como objetivo presentar los resultados de la implementación del fotodiagnóstico como herramienta en Educación Ambiental. El enfoque metodológico adoptado tiene un carácter cualitativo y se constituyó en dos etapas distintas y consecutivas. Se utilizó el análisis interpretativo, uno de los pasos que componen el análisis de contenido y la recopilación de datos, que se realizó a través de un grupo focal. Los resultados de la investigación demostraron que la fotografía puede ser una gran herramienta metodológica aliada a los procesos de sensibilización en educación ambiental para un cambio de comportamiento a través del reflejo de las imágenes por parte de sus participantes.A nova geração segue impulsionada com registros de imagens em qualquer lugar a qualquer hora, graças à tecnologia avançada que nos permite ver o mundo e situações de diversas maneiras e com riqueza de detalhes, o que possibilitou as várias pesquisas ligadas a fotografias criarem métodos como a fotoelicitação, a iconografia, a ecnografia, entre outros. Nessa pesquisa, utilizou-se o fotodiagnóstico com vistas à sensibilização de indivíduos para os impactos de resíduos sólidos em área de manguezal. Nesse sentido, este artigo visa apresentar os resultados da implementação do fotodiagnóstico como ferramenta em Educação Ambiental. A abordagem metodológica adotada tem caráter qualitativo e se constituiu em duas etapas distintas e consecutivas. Utilizou-se da análise interpretativa, uma das etapas que compõem a análise de conteúdo, e da coleta de dados, que ocorreu por meio de grupo focal. Os resultados da pesquisa demonstraram que a fotografia pode ser uma grande ferramenta metodológica aliada aos processos de sensibilização em educação ambiental para uma mudança de comportamento através da reflexão das imagens pelos seus participantes