Pullback attractors for a singularly nonautonomous plate equation

We consider the family of singularly nonautonomous plate equation with structural damping $$u_{tt} + a(t,x)u_{t} + (- \Delta) u_{t} + (-\Delta)^{2} u + \lambda u = f(u),$$ in a bounded domain $\Omega \subset \R^n$, with Navier boundary conditions. When the nonlinearity $f$ is dissipative we show that this problem is globally well posed in $H^2_0(\Omega) \times L^2(\Omega)$ and has a family of pullback attractors which is upper-semicontinuous under small perturbations of the damping $a$

Dynamic of Metabolic Indicators, Insulin Like-growth Factor I (IGF-I) and Cortisol in Holstein Cows during the Transition Period

Background: Physiological events occur in the transition period marked by negative energetic balance, where the energetic demand is higher due to fetal nutrition and lactogenesis and intensified by the decrease of the dry matter intake in the pre-partum period. The adaptation of cows is dependent of homeostatic and homeorhetic mechanisms regulated by catecholamine, cortisol, GH, IGF-I, insulin and glucagon but the priorization of homeorhetic mechanisms could result in metabolic diseases. Considering the scarce longitudinal studies about the Brazilian conditions the aim of this project was to evaluate the influence of transition period on metabolic indicators, cortisol and IGF-I in Holstein cows.Materials, Methods & Results: Thirteen cows, from 2nd to 4th lactation were evaluated weakly from week -2 to week +3 in relation to calving to determine the body condition score (BCS), metabolic and endocrine profile. The BCS decreased between week -2 (BCS = 4.0) and +1 (BCS = 3.0), followed by and slight increase on weeks +2 and +3 (P = 0.000). The most of metabolic indicators and hormones have changed during the transition period (P ≤ 0.05), especially around calving. It was possible to detect the peak of cortisol, glucose, non-esterified fatty acids (NEFA), ß-hydroxibutyrate (BHB), and aspartate aminotransferase (AST) on delivery and week +1. On the other hand, total calcium, triglycerides (TG) and cholesterol (CHOL) decreased was observed around parturition. Insulin like growth factor type I (IGF-I) showed marked reduction between pre and postpartum, and the lowest value was observed in the week +1. TP and GLOB had the lowest value on calving and globulin has a gradual increase from delivery to week +3.Discussion: Cows included in this experiment had dystocia (4/13, 30.8%), retention of placenta (1/13, 7.7%) and clinical hypocalcemia (1/13, 7.7%). One of the animals with episodes of dystocia was also aggravated by ketosis in week +1 and +2 (1/13, 7.7%). Uterine infections were observed in five animals (5/13, 38.4%). Of this total of animals with uterine infection (5/13), three had already expressed earlier disturbances: two cows had dystocia and one cow with retention of placenta. The weight loss observed between pre and postpartum may be due to an increase of energy demand for fetal maintenance and the concomitant initiation of lactation, in conjunction with an approximately 30% reduction in dry matter intake during the transitional period. The hyperglycemia concomitant with the peak of cortisol at delivery may be explaining by the activation of the somatotropic axis, due to the stress of calving. The increase of NEFA, BHB and AST around calving associated with decreased of TG and CHOL could be associated with homeorhetic mechanisms, especially lipolysis and gluconeogenesis. The IGF-I decrease in postpartum may be by the decreased expression of receptors for growth hormone (GH) in the liver, and consequently reduced synthesis and/or IGF-I hepatic clearance, which reduce of the negative feedback of IGF-I on GH secretion. The total calcium concentrations were below the threshold (8.50 mg/dL) established by Goff [10] at parturition, week +1 and +2 and probably is due to the secretion of 20-30 g of calcium per day during the colostrum synthesis. Total protein and albumin have a slight variation, except for the peak observed on week +3 due to uterine infection

From the Plate Tectonics to the Evolution Theory; from the supercontinents to the dispersion of the living beings

RESUMO: A evolução do conhecimento do interior do nosso planeta tem levado a profundas alterações da forma como a dinâmica da Terra é encarada, evidenciando a existência de ciclo dos supercontinentes. Esta transformação tem permitido uma visão mais integradora, onde os processos tectónicos e de evolução da Vida na Terra surgem como complementares. No entanto, esta nova abordagem ainda não se reflete nos curricula do ensino. A realiza ção de um conjunto de atividades práticas explorando a forma como os grandes blocos continentais foram evoluindo, desde o supercontinente Rodínia até à Atualidade, e a sua influência na dispersão de alguns dos prin cipais grupos de seres vivos, constitui uma abordagem eficiente de alguns aspetos associados ao ciclo dos supercontinentes.ABSTRACT: The evolution of the understanding of the behaviour of the inner layers of our planet led to deep changes in the way we see the Earth dynamics, emphasizing the existence of a supercontinent cycle. This allows an integrative perspective, where the Plate Tectonics and the Evolution of Life on Earth are no longer isolated processes, but the result of a common evolution. However, such innovative view is not yet reflected in the scholar curricula. In this work, we propose a set of practical activities for the sec ondary school level exploiting the concept ofsupercontinent cycle and disper sion of Life on Earth. The reconstruction of the dispersion of the major continental blocks,since Rodínia to the Actuality, allows the understanding, not only of the aggregation and dispersion of supercontinents (Rodínia → Panotia → Pangaea), but also the way they have influenced the dispersion of some of the major groups of animals in the Earth.info:eu-repo/semantics/publishedVersio

EFEITO NULO DA TERAPIA DE BIOCAMPO TOQUE QUÂNTICO SOBRE A GERMINAÇÃO DE SEMENTES DE SOJA (Glycine max)

As terapias de biocampo envolvendo imposição de mãos, como o toque quântico, seriam capazes de produzir efeito fisiológico. Não se sabe como ocorre essa influência, visto que o conhecimento científico atualmente disponível ainda não foi capaz de descrever e explicar o fenômeno das terapias de biocampo. O teste de germinação de sementes tem sido utilizado como marcador biológico fidedigno para avaliar o efeito físico de terapias de biocampo eliminando o efeito placebo. O objetivo do presente estudo foi avaliar o efeito do toque quântico sobre a germinação de sementes de soja (Glycine max). O procedimento experimental foi semelhante ao descrito por Creath e Schwartz (2004). Uma amostra de 400 sementes de soja foi dividida equitativamente em dois grupos: Experimental (com tratamento de toque quântico antes do teste de germinação) e Controle (sem tratamento antes do teste de germinação). Os resultados do presente estudo evidenciaram que o toque terapêutico não teve efeito sobre a velocidade de germinação e o comprimento médio das radículas. Contudo, o número de plântulas consideradas normais e saudáveis foi elevado no grupo de sementes que recebeu o toque terapêutico

SARS-CoV-2 uses CD4 to infect T helper lymphocytes

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here, we show that SARS-CoV-2 infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.</p