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1.
J Mol Graph Model ; 108: 107998, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34371459

RESUMO

We present a detailed study of the Li+ ion adsorption on two different hydrogenated carbon nanostructures, namely as pristine graphene (PG) and topologic Stone-Wales defective graphene (SWG) using the density functional theory (DFT). The studies are focused to analyze the structure-stability relationship with the estimated electronic and electrical properties for lithium-ion batteries (LIB) formed with an anode based on the Li/Li+#PG and Li/Li+#SWG systems. In addition, the electronic effects induced due to Li+ adsorption and the presence of SW defect on the graphene models were analyzed by the frontier molecular orbitals, ChelpG charges, Raman and UV-Vis spectra. It was verified that Li+ is more stably adsorbed on the edges on both graphene structures through an electrostatic interaction between cation and more negatively charged edges of nanostructures. TD-DFT calculations showed that the metallic nature of isolated graphene is disturbed after the adsorption of Li+, and this was demonstrated from the calculated HOMO-LUMO gap. The same Li+-Graphene geometries were optimized by introducing neutral charge in order to enable the calculation of ionization potentials. I was also found that such systems potentially contributed to the modeling of graphene-based anodes with reasonable electrical voltage responses estimated for a LIB. The simulation of Raman and UV-Vis spectra revealed significant variations in intensity and shifts the typical bands of graphene due to the presence of the Li+ ion that can contribute to point out new experiments to the spectroscopic characterization of these systems. Our results suggest that these carbon nanostructures are potential candidates for efficient applications in electrochemical systems, mainly dealing with LIB.


Assuntos
Grafite , Lítio , Adsorção , Fontes de Energia Elétrica , Eletrodos
2.
Allergy ; 69(7): 943-53, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24898675

RESUMO

BACKGROUND: Increased serum IgE levels are characteristic but not specific for allergic diseases. Particularly, severe atopic dermatitis (AD) overlaps with hyper-IgE syndromes (HIES) regarding eczema, eosinophilia, and increased serum IgE levels. HIES are primary immunodeficiencies due to monogenetic defects such as in the genes DOCK8 and STAT3. As it is not known to date why allergic manifestations are not present in all HIES entities, we assessed the specificity of serum IgE of AD and HIES patients in the context of clinical and immunological findings. METHODS: Clinical data, skin prick tests, specific IgE to aero- and food allergens, and T helper (Th) subpopulations were compared in AD and molecularly defined HIES patients. RESULTS: Total serum IgE levels were similarly increased in STAT3-HIES, DOCK8-HIES, and AD patients. The ratio of aeroallergen-specific IgE to total IgE was highest in AD, whereas DOCK8-HIES patients showed the highest specific serum IgE against food allergens. Overall, clinical allergy and skin prick test results complied with the specific IgE results. Th2-cell numbers were significantly increased in DOCK8-HIES and AD patients compared to STAT3-HIES patients and controls. AD patients showed significantly higher nTreg-cell counts compared to STAT3-HIES and control individuals. High Th17-cell counts were associated with asthma. Specific IgE values, skin prick test, and T-cell subsets of STAT3-HIES patients were comparable with those of healthy individuals except decreased Th17-cell counts. CONCLUSION: Hyper-IgE syndromes and atopic dermatitis patients showed different sensitization pattern of serum IgE corresponding to the allergic disease manifestations and Th-cell subset data, suggesting a key role of DOCK8 in the development of food allergy.


Assuntos
Dermatite Atópica/imunologia , Fatores de Troca do Nucleotídeo Guanina/imunologia , Imunoglobulina E/imunologia , Síndrome de Job/imunologia , Fator de Transcrição STAT3/imunologia , Adulto , Análise Mutacional de DNA , Dermatite Atópica/sangue , Feminino , Citometria de Fluxo , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Imunoglobulina E/sangue , Síndrome de Job/sangue , Síndrome de Job/genética , Masculino , Pessoa de Meia-Idade , Fator de Transcrição STAT3/genética , Testes Cutâneos , Linfócitos T Auxiliares-Indutores/imunologia , Adulto Jovem
3.
Genet Mol Res ; 12(4): 5889-904, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24301959

RESUMO

Weight records of Simmental beef cattle were used in a genetic evaluation of growth with and without embryo transfer (ET). A random regression model in which ET individuals were excluded (RRM1) contained 29,510 records from 10,659 animals, while another model that did not exclude these animals (RRM2) contained 62,895 records from 23,160 animals. The fixed and random regressions were represented by continuous functions, and a model with an order of three for the fixed curve and random effects was used to consider the homogeneity of residual variance. In general, the (co)variance components were similar in both models, except the maternal permanent environment and residual components. The direct heritability in RRM1 and RRM2 showed the same behavior with oscillations along the growth curve and were slightly higher in RRM1. Generally, the estimated correlations were the same and smaller as the ages distanced themselves. The inclusion of animals from ET in genetic evaluations can be done using random regression models; the inclusion of these animals would provide potential accuracy gains and greater genetic gains per unit time because of the reduction in the generation interval from the use of this reproductive technique.


Assuntos
Peso Corporal/genética , Bovinos/genética , Transferência Embrionária , Modelos Genéticos , Animais , Bovinos/crescimento & desenvolvimento , Característica Quantitativa Herdável , Análise de Regressão
4.
Genet Mol Res ; 12(3): 2465-80, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23979882

RESUMO

The Brazilian Association of Simmental and Simbrasil Cattle Farmers provided 29,510 records from 10,659 Simmental beef cattle; these were used to estimate (co)variance components and genetic parameters for weights in the growth trajectory, based on multi-trait (MTM) and random regression models (RRM). The (co)variance components and genetic parameters were estimated by restricted maximum likelihood. In the MTM analysis, the likelihood ratio test was used to determine the significance of random effects included in the model and to define the most appropriate model. All random effects were significant and included in the final model. In the RRM analysis, different adjustments of polynomial orders were compared for 5 different criteria to choose the best fit model. An RRM of third order for the direct additive genetic, direct permanent environmental, maternal additive genetic, and maternal permanent environment effects was sufficient to model variance structures in the growth trajectory of the animals. The (co)variance components were generally similar in MTM and RRM. Direct heritabilities of MTM were slightly lower than RRM and varied from 0.04 to 0.42 and 0.16 to 0.45, respectively. Additive direct correlations were mostly positive and of high magnitude, being highest at closest ages. Considering the results and that pre-adjustment of the weights to standard ages is not required, RRM is recommended for genetic evaluation of Simmental beef cattle in Brazil.


Assuntos
Peso Corporal/genética , Bovinos/genética , Animais , Animais Endogâmicos , Brasil , Bovinos/crescimento & desenvolvimento , Modelos Genéticos , Linhagem , Característica Quantitativa Herdável , Análise de Regressão
5.
Genet Mol Res ; 12(1): 528-36, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23512670

RESUMO

Random regression models were used to estimate the types and orders of random effects of (co)variance functions in the description of the growth trajectory of the Simbrasil cattle breed. Records for 7049 animals totaling 18,677 individual weighings were submitted to 15 models from the third to the fifth order including as fixed effects sex, contemporary group, feeding regimen, and type of reproduction and as random effects additive direct genetic effect, animal permanent environment, maternal additive genetic effect, and maternal permanent environment. The best-fit model presented order five to additive direct genetic effect, animal permanent environment, and maternal additive effect, with 6 classes of residual variances, and the maternal permanent environment effect was not significant, likely owing to the low average number of calves per cow. However, the model chosen for the growth curve presents three classes of residual variances, because even not showing the best fit it is more parsimonious, in addition to promoting a more realistic estimate of heritability.


Assuntos
Algoritmos , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Modelos Genéticos , Animais , Animais Recém-Nascidos , Peso Corporal/genética , Cruzamento , Feminino , Padrões de Herança/genética , Masculino , Análise de Regressão , Fatores de Tempo
6.
J Bone Joint Surg Br ; 94(4): 544-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22434473

RESUMO

There is no absolute method of evaluating healing of a fracture of the tibial shaft. In this study we sought to validate a new clinical method based on the systematic observation of gait, first by assessing the degree of agreement between three independent observers regarding the gait score for a given patient, and secondly by determining how such a score might predict healing of a fracture. We used a method of evaluating gait to assess 33 patients (29 men and four women, with a mean age of 29 years (15 to 62)) who had sustained an isolated fracture of the tibial shaft and had been treated with a locked intramedullary nail. There were 15 closed and 18 open fractures (three Gustilo and Anderson grade I, seven grade II, seven grade IIIA and one grade IIIB). Assessment was carried out three and six months post-operatively using videos taken with a digital camera. Gait was graded on a scale ranging from 1 (extreme difficulty) to 4 (normal gait). Bivariate analysis included analysis of variance to determine whether the gait score statistically correlated with previously validated and standardised scores of clinical status and radiological evidence of union. An association was found between the pattern of gait and all the other variables. Improvement in gait was associated with the absence of pain on weight-bearing, reduced tenderness over the fracture, a higher Radiographic Union Scale in Tibial Fractures score, and improved functional status, measured using the Brazilian version of the Short Musculoskeletal Function Assessment questionnaire (all p < 0.001). Although further study is needed, the analysis of gait in this way may prove to be a useful clinical tool.


Assuntos
Avaliação da Deficiência , Fixação Intramedular de Fraturas/reabilitação , Consolidação da Fratura/fisiologia , Marcha , Fraturas da Tíbia/cirurgia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Recuperação de Função Fisiológica , Fraturas da Tíbia/fisiopatologia , Fraturas da Tíbia/reabilitação , Resultado do Tratamento , Gravação em Vídeo , Adulto Jovem
7.
Arq. bras. med. vet. zootec ; 52(5): 527-33, out. 2000. tab
Artigo em Português | LILACS | ID: lil-285606

RESUMO

Registros de pesos ao nascimento, aos 100, 205, 365 e 550 dias de idade, de 7587 animais controlados pela Associaçäo Brasileira de Criadores da Raça Simental, criados em 150 fazendas e em diversos estados do Brasil, foram usados para estimar os componentes de variância e os parâmetros genéticos dessas características. O peso padronizado aos 205 dias (desmama) foi usado como característica "âncora". O aplicativo MTDFREML, sob modelo animal completo, foi utilizado para análise dos dados. As estimativas de herdabilidades total, direta e materna e as correlaçöes genéticas entre os efeitos materno e direto e os maternos permanentes foram obtidas mediante análises bicaracterísticas. Os seguintes valores foram encontrados: 0,23, 0,22, 0,05, -0,10, 0,07 para peso ao nascer; 0,09, 0,08, 0,00, 0,85, 0,17 para peso aos 100 dias de idade; 0,13, 0,13, 0,05, -0,17, 0,02 para peso aos 205 dias de idade; 0,15, 0,19, 0,06, -0,41, 0,03 para peso aos 365 dias de idade. A herdabilidade direta estimada para o peso aos 550 dias de idade, na análise bicaracterística com o peso à desmama, foi de 0,24. Exceto para peso ao nascimento (moderado), as correlaçöes genética, fenotípica e ambiente entre peso à desmama e as outras características foram altas e positivas. Os efeitos maternos foram importantes e devem ser incluídos nos programas de melhoramento da raça Simental


Assuntos
Animais , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Aumento de Peso/genética , Análise de Variância
8.
Arq. bras. med. vet. zootec ; 51(4): 363-70, ago. 1999. ilus, tab
Artigo em Português | LILACS | ID: lil-261002

RESUMO

Informaçöes de genealogia e produçäo, cedidas pela Associaçäo Brasileira de Criadores da Raça Simental (ABCRS), relativas aos pesos desde o nascimento até um ano de idade, foram utilizadas para estimar, sob modelos alternativos, os componentes de variância e os parâmetros genéticos em animais da raça Simental no Brasil. A matriz de parentesco inclui 25.812 animais dos quais 7587 com dados de produçäo. O modelo 1 contém, além do erro, o efeito genético direto. Os modelos seguintes contêm os componentes do modelo 1, mais o efeito permanente de ambiente materno (modelo 2), ou o componente genético materno (modelo 3), ambos os componentes (modelo 5), os componentes do modelo 3 mais a covariância entre os efeitos genéticos direto e materno (modelo 4) e todos os componentes citados (modelo 6). Os modelos foram comparados pelo teste de razäo de verossimilhança pelo x2 (P<0,01). Os componentes de variância e os valores de herdabilidades, estimados para os efeitos direto e materno, foram decrescentes, desde o modelo 1 até o modelo 6, na razäo direta em que o modelo incorpora mais efeitos aleatórios. Para a fase de aleitamento foi encontrada variância genética nula, entretanto, alto valor para a variância de ambiente permanente. Os efeitos maternos, genético e de ambiente permanente säo importantes para a raça Simental no Brasil e devem ser considerados em programas de seleçäo. Entretanto, os valores mais elevados de herdabilidade materna,encontrados com modelos sem efeito de ambiente permanente, sugerem que o método utilizado näo discrimina apropriadamente esses efeitos, oriundos de mesma fonte de variaçäo


Assuntos
Bovinos , Genética
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