Contributos da epistemologia sistémica na investigação com famílias

Considerando a importância dos estudos científicos com famílias e o crescente interesse dos investigadores por esta temática, tanto nas ciências psicológicas como noutras (e.g., educação), esta reflexão foca a utilização de uma abordagem teórica e metodológica, fundamentada na epistemologia sistémica, no desenvolvimento da investigação com famílias. Para o efeito, apresentam-se exemplos de diferentes investigações, baseadas nesta epistemologia, e evidenciam-se as diferenças entre o paradigma “tradicional” (e.g., Descartes) e o paradigma sistémico: simplicidade versus complexidade; estabilidade versus instabilidade; objetividade versus intersubjetividade. Pensar e investigar sistemicamente as famílias implica: cruzar fontes e níveis de informação, focar a análise na relação, contextualizar social, cultural e historicamente, considerar o fator tempo e a perspetiva longitudinal, e, finalmente, recorrer à triangulação metodológica. Resumindo, estudar as famílias, através de uma perspetiva sistémica, requer uma atitude de contextualização e de reconhecimento da causalidade recursiva, o que pode ser favorecido pela combinação de diferentes estratégias e instrumentos metodológicos.Considering the importance of scientific studies with families and the growing interest of researchers in this subject, in psychological and in other sciences (e.g., education), this work focus on the use of a theoretical and methodological approach, based on systemic epistemology, within the development in families’ research. Therefore, different research’ examples are presented, according to that epistemology, and the differences between the “traditional” (e.g., Descartes) and systemic paradigms are evidenced: simplicity versus complexity; stability versus instability; objectivity versus intersubjetivity. Thinking and researching families in a systemic way implies: crossing sources and informative levels, focusing the analysis on relation, considering the social, cultural and historical context, as well as the time factor and a longitudinal perspective and, finally, using methodological triangulation. In summary, studying families, through a systemic perspective, requires an attitude of contextualization and recursive causality awareness, which could be improved by the combination of different methodological strategies and instruments.info:eu-repo/semantics/publishedVersio

Pioglitazone corrects dysregulation of skeletal muscle mitochondrial proteins involved in ATP synthesis in type 2 diabetes

Context: In this study, we aimed to identify the determinants of mitochondrial dysfunction in skeletal muscle (SKLM) of subjects with type 2 diabetes (T2DM), and to evaluate the effect of pioglitazone (PIO) on SKLM mitochondrial proteome. Methods: Two different groups of adults were studied. Group I consisted of 8 individuals with normal glucose tolerance (NGT) and 8 with T2DM, subjected to SKLM mitochondrial proteome analysis by 2D-gel electrophoresis followed by mass spectrometry-based protein identification. Group II included 24 individuals with NGT and 24 with T2DM, whose SKLM biopsies were subjected to immunoblot analysis. Of the 24 subjects with T2DM, 20 were randomized to receive placebo or PIO (15 mg daily) for 6 months. After 6 months of treatment, SKLM biopsy was repeated. Results: Mitochondrial proteomic analysis on Group I revealed that several mitochondrial proteins involved in oxidative metabolism were differentially expressed between T2DM and NGT groups, with a downregulation of ATP synthase alpha chain (ATP5A), electron transfer flavoprotein alpha-subunit (ETFA), cytochrome c oxidase subunit VIb isoform 1 (CX6B1), pyruvate dehydrogenase protein X component (ODPX), dihydrolipoamide dehydrogenase (DLDH), dihydrolipoamide-S-succinyltransferase (DLST), and mitofilin, and an up-regulation of hydroxyacyl-CoA-dehydrogenase (HCDH), 3,2-trans-enoyl-CoA-isomerase (D3D2) and delta3,5-delta2,4-dienoyl-CoA-isomerase (ECH1) in T2DM as compared to NGT subjects. By immunoblot analysis on SKLM lysates obtained from Group II we confirmed that, in comparison to NGT subjects, those with T2DM exhibited lower protein levels of ATP5A (−30%, P = 0.006), ETFA (−50%, P = 0.02), CX6B1 (−30%, P = 0.03), key factors for ATP biosynthesis, and of the structural protein mitofilin (−30%, P = 0.01). T2DM was associated with a reduced abundance of the enzymes involved in the Krebs cycle DLST and ODPX (−20%, P ≤ 0.05) and increased levels of HCDH and ECH1, enzymes implicated in the fatty acid catabolism (+30%, P ≤ 0.05). In subjects with type 2 diabetes treated with PIO for 6 months we found a restored SKLM protein abundance of ATP5A, ETFA, CX6B1, and mitofilin. Moreover, protein levels of HCDH and ECH1 were reduced by −10% and − 15% respectively (P ≤ 0.05 for both) after PIO treatment. Conclusion: Type 2 diabetes is associated with reduced levels of mitochondrial proteins involved in oxidative phosphorylation and an increased abundance of enzymes implicated in fatty acid catabolism in SKLM. PIO treatment is able to improve SKLM mitochondrial proteomic profile in subjects with T2DM

Interação de frações proteicas de Chromobacterium violaceum com esporos de Colletotrichum sp. isolado de guaranazeiro.

O objetivo deste trabalho foi testar extratos proteicos de C. violaceum fracionados por diferenças de solubilidade dos seus componentes quanto à atividade inibitória da protrusão de hifas de Colletotrichum sp. isolado de folhas de guaranazeiro (Paullinia cupana var. sorbilis) com sintomas de antracnose, principal doença dos guaranazais no Amazonas

Bayesian Comparison of Neurovascular Coupling Models Using EEG-fMRI

Functional magnetic resonance imaging (fMRI), with blood oxygenation level-dependent (BOLD) contrast, is a widely used technique for studying the human brain. However, it is an indirect measure of underlying neuronal activity and the processes that link this activity to BOLD signals are still a topic of much debate. In order to relate findings from fMRI research to other measures of neuronal activity it is vital to understand the underlying neurovascular coupling mechanism. Currently, there is no consensus on the relative roles of synaptic and spiking activity in the generation of the BOLD response. Here we designed a modelling framework to investigate different neurovascular coupling mechanisms. We use Electroencephalographic (EEG) and fMRI data from a visual stimulation task together with biophysically informed mathematical models describing how neuronal activity generates the BOLD signals. These models allow us to non-invasively infer the degree of local synaptic and spiking activity in the healthy human brain. In addition, we use Bayesian model comparison to decide between neurovascular coupling mechanisms. We show that the BOLD signal is dependent upon both the synaptic and spiking activity but that the relative contributions of these two inputs are dependent upon the underlying neuronal firing rate. When the underlying neuronal firing is low then the BOLD response is best explained by synaptic activity. However, when the neuronal firing rate is high then both synaptic and spiking activity are required to explain the BOLD signal

A Low Dimensional Description of Globally Coupled Heterogeneous Neural Networks of Excitatory and Inhibitory Neurons

Neural networks consisting of globally coupled excitatory and inhibitory nonidentical neurons may exhibit a complex dynamic behavior including synchronization, multiclustered solutions in phase space, and oscillator death. We investigate the conditions under which these behaviors occur in a multidimensional parametric space defined by the connectivity strengths and dispersion of the neuronal membrane excitability. Using mode decomposition techniques, we further derive analytically a low dimensional description of the neural population dynamics and show that the various dynamic behaviors of the entire network can be well reproduced by this reduced system. Examples of networks of FitzHugh-Nagumo and Hindmarsh-Rose neurons are discussed in detail

Temporal patterns of bat activity on the High Plains of Texas

Texas is home to more wind turbines and more bat species than any other state in the United States. Insectivorous bats provide an important economical ecosystem service in this region through agricultural pest regulation. Unfortunately, bats can be impacted negatively by wind turbines, and migratory bat species particularly so. To understand how bat activity changes throughout the year in western Texas, activity was monitored through echolocation calls and opportunistic mist-netting efforts over a period of four years (2012–2015). Peaks in activity were observed from March through April, and again in September, which coincides with previously documented migratory periods for many species native to the High Plains of Texas. Findings presented herein suggest that urban habitats are preferred stopover sites for migratory bat species while traversing arid regions such as those occurring in western Texas. In addition to human-made structures, urban habitats harbor non-native trees that provide suitable roost sites, aggregations of insect prey swarming outdoor light sources, and artificial water sources. It is important to understand bat activity in western Texas, not only for the benefit of agricultural pest suppression, but also to predict how the expansion of wind energy may affect bat populations in this region