RESUMO
Experimental realizations of two-dimensional materials are hardly free of structural defects such as e.g. vacancies, which, in turn, modify drastically its pristine physical defect-free properties. In this work, we explore effects due to point defect clustering on the electronic and transport properties of bilayer graphene nanoribbons, for AA and AB stacking and zigzag and armchair boundaries, by means of the tight-binding approach and scattering matrix formalism. Evident vacancy concentration signatures exhibiting a maximum amplitude and an universality regardless of the system size, stacking and boundary types, in the density of states around the zero-energy level are observed. Our results are explained via the coalescence analysis of the strong sizeable vacancy clustering effect in the system and the breaking of the inversion symmetry at high vacancy densities, demonstrating a similar density of states for two equivalent degrees of concentration disorder, below and above the maximum value.
RESUMO
OBJECTIVE: The purpose of this study was to investigate the use of saliva for the identification of human cytomegalovirus (HCMV) in allogeneic hematopoietic stem cell transplant patients by real time PCR compared with blood. MATERIALS AND METHODS: Saliva and blood samples were sampled weekly in 30 allogeneic hematopoietic stem cell transplant patients until 100 days after transplant. Total genomic DNA, extracted from saliva and whole-blood samples, was used for HCMV real time PCR. Nonparametric tests were performed, and P value Assuntos
Citomegalovirus/isolamento & purificação
, DNA Viral/análise
, Transplante de Células-Tronco Hematopoéticas
, Saliva/virologia
, Adolescente
, Adulto
, Antígenos Virais/análise
, Antígenos Virais/sangue
, Antivirais/uso terapêutico
, Criança
, Citomegalovirus/genética
, Citomegalovirus/imunologia
, Infecções por Citomegalovirus/diagnóstico
, Infecções por Citomegalovirus/tratamento farmacológico
, DNA Viral/sangue
, Estudos de Viabilidade
, Feminino
, Seguimentos
, Ganciclovir/uso terapêutico
, Humanos
, Estudos Longitudinais
, Masculino
, Pessoa de Meia-Idade
, Fosfoproteínas/análise
, Fosfoproteínas/sangue
, Reação em Cadeia da Polimerase
, Estudos Prospectivos
, Transplante Homólogo
, Carga Viral
, Proteínas da Matriz Viral/análise
, Proteínas da Matriz Viral/sangue
, Viremia/virologia
, Ativação Viral
, Adulto Jovem
RESUMO
Accuracy of the information is essential to produce unbiased estimates of the association between exposure and outcome. We are carrying out a case-control study which aim is to investigate the association between the use of medication and falling injuries leading to hospitalisation in the elderly. As there is no gold-standard available, we estimated the reliability of the information on the use of these drugs within the 24 hours and two weeks before the fall using a test-retest strategy. Sixty-one individuals aged 60 years or more were re-interviewed within an interval of 5-7 days after the first interview. Kappa coefficients were high, showing a good consistency of collected data on medication recently used. Among the variables investigated, only gender showed an association with reliability of the information, which was more consistent among women compared to men.