The missing ingredient in effective-medium theories: Standard deviations

Effective-medium theories for electromagnetic constitutive parameters of particulate composite materials are theories of averages. Standard deviations are absent because of the lack of rigorous theories. But ensemble averages and standard deviations can be calculated from a rigorous theory of reflection by planar multilayers. Average reflectivities at all angles of incidence and two orthogonal polarization states for a multilayer composed of two kinds of electrically thin layers agree well with reflectivities for a single layer with the same overall thickness and a volume-weighted average of the relative permittivities of these two components. But the relative standard deviation can be appreciable depending on the angle of incidence and the polarization state of the incident illumination, and increases with increasing difference between the constitutive parameters of the two layers. This suggests that average constitutive parameters obtained from effective-medium theories do not have uniform validity for all calculations in which they might be used.Comment: 12 pages (accepted for publication in Journal of Modern Optics

Decentralized Estimation over Orthogonal Multiple-access Fading Channels in Wireless Sensor Networks - Optimal and Suboptimal Estimators

Optimal and suboptimal decentralized estimators in wireless sensor networks (WSNs) over orthogonal multiple-access fading channels are studied in this paper. Considering multiple-bit quantization before digital transmission, we develop maximum likelihood estimators (MLEs) with both known and unknown channel state information (CSI). When training symbols are available, we derive a MLE that is a special case of the MLE with unknown CSI. It implicitly uses the training symbols to estimate the channel coefficients and exploits the estimated CSI in an optimal way. To reduce the computational complexity, we propose suboptimal estimators. These estimators exploit both signal and data level redundant information to improve the estimation performance. The proposed MLEs reduce to traditional fusion based or diversity based estimators when communications or observations are perfect. By introducing a general message function, the proposed estimators can be applied when various analog or digital transmission schemes are used. The simulations show that the estimators using digital communications with multiple-bit quantization outperform the estimator using analog-and-forwarding transmission in fading channels. When considering the total bandwidth and energy constraints, the MLE using multiple-bit quantization is superior to that using binary quantization at medium and high observation signal-to-noise ratio levels

Development of a culturally sensitive life review program for Chinese patients with advanced cancer

2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

EFEITOS DA INTOXICAÇÃO AGUDA COM ETANOL SOBRE A EXSUDAÇÃO DE NEUTRÓFILOS PARA A CAVIDADE PERITOENAL DE EM CAMUNDONGOS INOCULADOS COM Staphilococcus aureus.

Introdução. Há demonstrações que uma intoxicação aguda pelo etanol tem efeitos antiinflamatórios, com redução da exsudação de neutrófilos e com aumento da susceptibilidade a bactérias, especialmente Streptococcus pneumoniae. No entanto não se conhece o tempo durante o qual persistem os efeitos inibidores da exsudação celular e da redução da atividade microbicida de leucócitos, após a intoxicação etílica aguda. Objetivos. Avaliar o tempo após uma intoxicação etílica aguda no qual persistem os efeitos inibidores da exsudação de neutrófilos e a redução da capacidade microbicida do exsudato inflamatório em um modelo de peritonite induzida por Staphylococcus aureus. Métodos. Camundongos C57BL/6 receberam, por gavagem, uma dose de 7mg de etanol/g peso corporal em solução a 40%. Uma, 12,24, 48 e 72 horas após, receberam uma inoculação intraperitoneal de Staphylococcus aureus (0,5 ml contendo 6 a 9x108 UFC/mL; cepa ATCC 25923). Seis horas depois, os animais eram eutanasiados e a cavidade peritoneal lavada com PBS/EDTA 0,01M; uma alíquota era utilizada para contagem do número de UFC e a outra para contagem global e específica das células do exsudato utilizando câmara de Neubauer e citocentrífuga para confecção de esfregaços, corados por corante hematológico rápido (Dipquick). A contagem de UFC foi feita pelo método de diluição seriada com semeadura em placas de ágar Müller-Hinton. Resultados. Todos os animais que receberam etanol apresentaram sinais de embriaguês, que chegou a um estado de letargia profunda do qual todos os animais se recuperavam em, no máximo, 45 minutos. A dose de etanol utilizada induziu involução do timo, evidente 24 horas após a alcoolização, mas com recuperação após 120 horas. Nos animais alcoolizados que receberam o inóculo do estafilococo houve redução significativa da exsudação celular, devido a redução da exsudação de neutrófilos, até 24 horas após a ingestão do etanol. A análise dos esfregaços mostrava maior quantidade de bactérias fora das células no grupo etanol e o número de UFC foi maior no período avaliado, mas a diferença não foi estatisticamente significativa. Conclusão. Confirma-se os efeitos antiinflamatórios da intoxicação etílica aguda, com redução significativa no exsudato de leucócitos, até 24 horas após a exposição ao etanol; essa redução decorre especialmente da redução da exsudação de neutrófilos, já que o número de mononucleares exsudados no período avaliado foi semelhante nos dois grupos experimentais. O poder microbicida da cavidade peritoneal frente aos estafilococos foi menor no grupo etanol embora sem significância estatística, possivelmente porque os macrófagos residentes foram menos afetados pelos efeitos do etanol. Palavras-chaves: Alcoolismo agudo, neutrófilos, inflamação

From regional pulse vaccination to global disease eradication: insights from a mathematical model of Poliomyelitis

Mass-vaccination campaigns are an important strategy in the global fight against poliomyelitis and measles. The large-scale logistics required for these mass immunisation campaigns magnifies the need for research into the effectiveness and optimal deployment of pulse vaccination. In order to better understand this control strategy, we propose a mathematical model accounting for the disease dynamics in connected regions, incorporating seasonality, environmental reservoirs and independent periodic pulse vaccination schedules in each region. The effective reproduction number, $R_e$, is defined and proved to be a global threshold for persistence of the disease. Analytical and numerical calculations show the importance of synchronising the pulse vaccinations in connected regions and the timing of the pulses with respect to the pathogen circulation seasonality. Our results indicate that it may be crucial for mass-vaccination programs, such as national immunisation days, to be synchronised across different regions. In addition, simulations show that a migration imbalance can increase $R_e$ and alter how pulse vaccination should be optimally distributed among the patches, similar to results found with constant-rate vaccination. Furthermore, contrary to the case of constant-rate vaccination, the fraction of environmental transmission affects the value of $R_e$ when pulse vaccination is present.Comment: Added section 6.1, made other revisions, changed titl

Domain wall brane in squared curvature gravity

We suggest a thick braneworld model in the squared curvature gravity theory. Despite the appearance of higher order derivatives, the localization of gravity and various bulk matter fields is shown to be possible. The existence of the normalizable gravitational zero mode indicates that our four-dimensional gravity is reproduced. In order to localize the chiral fermions on the brane, two types of coupling between the fermions and the brane forming scalar is introduced. The first coupling leads us to a Schr\"odinger equation with a volcano potential, and the other a P\"oschl-Teller potential. In both cases, the zero mode exists only for the left-hand fermions. Several massive KK states of the fermions can be trapped on the brane, either as resonant states or as bound states.Comment: 18 pages, 5 figures and 1 table, references added, improved version to be published in JHE

Prevalence of Hepatitis E Virus in Swine Fed on Kitchen Residue

The aim of this study was to investigate the prevalence of swine hepatitis E virus (HEV) in pigs fed different feedstuffs (kitchen residue or mixed feeds) and genetic identification of HEV isolated in Hebei province, China. Serum and fecal samples were collected from adult swine. Anti-HEV antibody was evaluated by double sandwich antigen enzyme immunoassay. HEV RNA was extracted from fecal samples and amplified by nested RT-PCR. The reaction products were sequenced, and the sequence analyzed. Virus-like particles were distinguishable by negative staining in the electron microscope. Histopathological observation and immunohistochemical localization were used in the animal models. Overall, the anti-HEV positive percentage of serum samples from pigs fed on kitchen residue was 87.10% (27/31), and 53.06% (130/245) from pigs fed on complete feed. The HEV RNA positivity rate of fecal samples from pigs fed on kitchen residue was 61.54% (8/13), but zero for pigs fed on complete feed. Sequence analysis of these eight samples and comparison with the published sequence showed that there were eight groups that belonged to genotype 4 d and the nucleotide identity was 95.6–99.3%. swHE11 is most closely related to strain CCC220, and the other seven HEV isolates were most closely related to strains swGX40, SwCH189 and V0008ORF3, which are isolates from human and pigs. Histopathological observation showed that there was liver damage in the experimental group, and immunohistochemistry indicated that the HEV antigens were strongly positive at 7 days after infection. The results demonstrated that the prevalence of HEV in pigs fed on kitchen residue was higher than in those fed on complete feed (P<0.05)

Allogeneic hematopoietic stem cell transplantation in China: where we are and where to go

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective and sometimes the only curative therapy for patients with certain hematological diseases. Allo-HSCT has been practiced in China for approximately 30 years, and great improvements have been made within the past decade, particularly in fields such as the haploidentical HSCT system, strategies to overcome relapse and GVHD, and modified HSCT for elderly patients. This review will describe the current situation and provide a prospective of these unique aspects of Allo-HSCT in China