2,487 research outputs found
The cerebellum in Parkinson's disease and parkinsonism in cerebellar disorders
Universidade Federal de São Paulo, Ataxia Unit, Dept Neurol, São Paulo, BrazilUniversidade Federal de São Paulo, Ataxia Unit, Dept Neurol, São Paulo, BrazilWeb of Scienc
Epitope-dependent Selection of Highly Restricted or Diverse T Cell Receptor Repertoires in Response to Persistent Infection by Epstein-Barr Virus
The T cell receptor (TCR) repertoires of cytotoxic responses to the immunodominant and subdominant HLA A11–restricted epitopes in the Epstein-Barr virus (EBV) nuclear antigen-4 were investigated in four healthy virus carriers. The response to the subdominant epitope (EBNA4 399-408, designated AVF) was highly restricted with conserved Vβ usage and identical length and amino acid motifs in the third complementarity-determining regions (CDR3), while a broad repertoire using different combinations of TCR-α/β V and J segments and CDR3 regions was selected by the immunodominant epitope (EBNA4 416-424, designated IVT). Distinct patterns of interaction with the A11–peptide complex were revealed for each AVF- or IVT-specific TCR clonotype by alanine scanning mutagenesis analysis. Blocking of cytotoxic function by antibodies specific for the CD8 coreceptor indicated that, while AVF-specific TCRs are of high affinity, the oligoclonal response to the IVT epitope includes both low- and high-affinity TCRs. Thus, comparison of the memory response to two epitopes derived from the same viral antigen and presented through the same MHC class I allele suggests that immunodominance may correlate with the capacity to maintain a broad TCR repertoire
Ferramenta computacional para análise de imagens de ensaios mecânicos de dureza
Este artigo apresenta uma ferramenta computacional capaz de determinar as durezas Brinell e Vickers a partir de imagens de identações. A referida ferramenta integra algoritmos de processamento e análisede imagem, como crescimento de regiões e contornos ativos (snakes). Para validar a ferramenta proposta, foram realizadas comparações dos resultados obtidos por ela e pelo processo convencional a partir de identações realizadas no aço ABNT 1020. A partir dessa comparação, pode-se afirmar que a ferramenta desenvolvida é mais rápida, intuitiva na sua aplicação e menos dependente da subjetividade do operador
Larval anatomy of Dendropsophus decipiens (A. Lutz 1925) (Anura: Hylidae: Dendropsophini) with considerations to larvae of this genus
The Dendropsophus decipiens clade comprises four species: D. berthalutzae, D. decipiens, D. haddadi, and D. oliveirai. Tadpoles of these species were described, but data on their internal morphology are lacking. We provide the first description of the buccopharyngeal anatomy, chondrocranial morphology, and cranial, hyoid and hyobranchial musculature of the tadpole of D. decipiens. Larvae of D. decipiens are characterized by the absence of lingual papillae, presence of fan-like papilla on the buccal floor, presence of a single-element suprarostral cartilage, presence of a small triangular process at the basis of the processus muscularis, m. levator mandibulae lateralis inserted on the nasal sac, and m. subarcualis rectus II-IV with a single, continuous slip. Tadpoles are likely macrophagous, although not as specialized as those of other species of the genus, suggesting some degree of diversification on the feeding habits within Dendropsophus.Fil: Dias, Pedro H. S.. Universidade de Sao Paulo; BrasilFil: de Araujo Vieira, Katyuscia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: de Carvalho-e-Silva, Ana Maria P. T.. Universidade Federal do Rio de Janeiro; BrasilFil: Orrico, Victor G. D.. Universidade Estadual de Santa Cruz; Brasi
Energy production predication via Internet of Thing based machine learning system
© 2019 Elsevier B.V. Wind energy is an interesting source of alternative energy to complement the Brazilian energy matrix. However, one of the great challenges lies in managing this resource, due to its uncertainty behavior. This study addresses the estimation of the electric power generation of a wind turbine, so that this energy can be used efficiently and sustainable. Real wind and power data generated in set of wind turbines installed in a wind farm in Ceará State, Brazil, were used to obtain the power curve from a wind turbine using logistic regression, integrated with Nonlinear Autoregressive neural networks to forecast wind speeds. In our system the average error in power generation estimate is of 29 W for 5 days ahead forecast. We decreased the error in the manufacturer\u27s power curve in 63%, with a logics regression approach, providing a 2.7 times more accurate estimate. The results have a large potential impact for the wind farm managers since it could drive not only the operation and maintenance but management level of energy sells
Classification of induced magnetic field signals for the microstructural characterization of sigma phase in duplex stainless steels
Duplex stainless steels present excellent mechanical and corrosion resistance properties.However, when heat treated at temperatures above 600 ºC, the undesirable tertiary sigma phaseis formed. This phase presents high hardness, around 900 HV, and it is rich in chromium, thematerial toughness being compromised when the amount of this phase is not less than 4%. Thiswork aimed to develop a solution for the detection of this phase in duplex stainless steels throughthe computational classification of induced magnetic field signals. The proposed solution is based onan Optimum Path Forest classifier, which was revealed to be more robust and effective than Bayes,Artificial Neural Network and Support Vector Machine based classifiers. The induced magneticfield was produced by the interaction between an applied external field and the microstructure.Samples of the 2205 duplex stainless steel were thermal aged in order to obtain different amounts ofsigma phases (up to 18% in content). The obtained classification results were compared against theones obtained by Charpy impact energy test, amount of sigma phase, and analysis of the fracturesurface by scanning electron microscopy and X-ray diffraction. The proposed solution achieved aclassification accuracy superior to 95% and was revealed to be robust to signal noise, being thereforea valid testing tool to be used in this domain
Genetic and epigenetic profiling of BRCA1/2 in ovarian tumors reveals additive diagnostic yield and evidence of a genomic BRCA1/2 DNA methylation signature
Poly-ADP-ribose-polymerase inhibitor (PARPi) treatment is indicated for advanced-stage ovarian tumors with BRCA1/2 deficiency. The “BRCAness” status is thought to be attributed to a tumor phenotype associated with a specific epigenomic DNA methylation profile. Here, we examined the diagnostic impact of combined BRCA1/2 sequence, copy number, and promoter DNA methylation analysis, and evaluated whether genomic DNA methylation patterns can predict the BRCAness in ovarian tumors. DNA sequencing of 172 human tissue samples of advanced-stage ovarian adenocarcinoma identified 36 samples with a clinically significant tier 1/2 sequence variants (point mutations and in/dels) and 9 samples with a CNV causing a loss of function in BRCA1/2. DNA methylation analysis of the promoter of BRCA1/2 identified promoter hypermethylation of BRCA1 in two mutation-negative samples. Computational modeling of genome-wide methylation markers, measured using Infinium EPIC arrays, resulted in a total accuracy of 0.75, sensitivity: 0.83, specificity: 0.64, positive predictive value: 0.76, negative predictive value: 0.74, and area under the receiver’s operating curve (AUC): 0.77, in classifying tumors harboring a BRCA1/2 defect from the rest. These findings indicate that the assessment of CNV and promoter DNA methylation in BRCA1/2 increases the cumulative diagnostic yield by 10%, compared with the 20% yield achieved by sequence variant analysis alone. Genomic DNA methylation data can partially predict BRCAness in ovarian tumors; however, further investigation in expanded BRCA1/2 cohorts is needed, and the effect of other double strand DNA repair gene defects in these tumors warrants further investigations
Temperature-Driven Developmental Modulation of Yield Response to Nitrogen in Wheat and Maize
Nitrogen management is central to the economic and environmental dimensions of agricultural sustainability. Yield response to nitrogen fertilisation results from multiple interacting factors. Theoretical frameworks are lagging for the interaction between nitrogen and air temperature, the focus of this study. We analyse the relation between yield response to nitrogen fertiliser and air temperature in the critical period of yield formation for spring wheat in Australia, winter wheat in the US, and maize in both the US and Argentina. Our framework assumes (i) yield response to nitrogen fertiliser is primarily related to grain number per m2, (ii) grain number is a function of three traits: the duration of the critical period, growth rate during the critical period, and reproductive allocation, and (iii) all three traits vary non-linearly with temperature. We show that “high” nitrogen supply may be positive, neutral, or negative for yield under “high” temperature, depending on the part of the response curve captured experimentally. The relationship between yield response to nitrogen and mean temperature in the critical period was strong in wheat and weak in maize. Negative associations for both spring wheat in Australia and winter wheat with low initial soil nitrogen ( 120 kg N ha-1) that favoured grain number and compromised grain fill, the relation between yield response to nitrogen and temperature was positive for winter wheat. The framework is particularly insightful where data did not match predictions; a non-linear function integrating development, carbon assimilation and reproductive partitioning bounded the pooled data for maize in the US and Argentina, where water regime, previous crop, and soil nitrogen overrode the effect of temperature on yield response to nitrogen fertilisation.Fil: Sadras, Victor O.. University of Adelaide; Australia. South Australian Research And Development Institute; AustraliaFil: Giordano, Nicolas. Kansas State University; Estados UnidosFil: Correndo, Adrian. Kansas State University; Estados UnidosFil: Cossani, C. Mariano. University of Adelaide; Australia. South Australian Research And Development Institute; AustraliaFil: Ferreyra, Juan M.. No especifíca;Fil: Caviglia, Octavio Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Entre Ríos; ArgentinaFil: Coulter, Jeffrey A.. University of Minnesota; Estados UnidosFil: Ciampitti, Ignacio Antonio. Kansas State University; Estados UnidosFil: Lollato, Romulo P.. Kansas State University; Estados Unido
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