Spin-phase-space-entropy production

Quantifying the degree of irreversibility of an open system dynamics represents a problem of both fundamental and applied relevance. Even though a well-known framework exists for thermal baths, the results give diverging results in the limit of zero temperature and are also not readily extended to nonequilibrium reservoirs, such as dephasing baths. Aimed at filling this gap, in this paper we introduce a phase-space-entropy production framework for quantifying the irreversibility of spin systems undergoing Lindblad dynamics. The theory is based on the spin Husimi-Q function and its corresponding phase-space entropy, known as Wehrl entropy. Unlike the von Neumann entropy production rate, we show that in our framework, the Wehrl entropy roduction rate remains valid at any temperature and is also readily extended to arbitrary nonequilibrium baths. As an application, we discuss the irreversibility associated with the interaction of a two-level system with a single-photon pulse, a problem which cannot be treated using the conventional approach.Comment: 12 pages, 16 figure

Association among weight loss, bone mass, body composition and dietary intake of post-pubertal obese adolescents

OBJECTIVE: To verify the effects of weight loss on bone mass of obese adolescents submitted to a nutritional intervention based on a hypocaloric diet and nutritional advice over a nine-month-period. METHODS: Anthropometry, body composition, BMD and dietary intake were evaluated. RESULTS: Fifty-five adolescents, 78.2% females, within an average age of 16.6 (1.4) years old participated in the study. Sixteen participants who completed the study did not lose weight. The group that adhered to the nutritional intervention had a mean weight loss of 6.2 (4.6)% baseline. There was a significant increase in total BMD and bone mineral content (BMC) in those adolescents who did not lose weight, while increased BMC and bone area were verified in participants who lost weight, mainly when associated with body composition alterations while changing weight. CONCLUSION: The increment in bone mineral density, even throughout weight loss, has showed no negative effect on bone mass and has also emphasized the importance of nutritional improvement in total bone mass during adolescence.OBJETIVO: Verificar os efeitos da perda de peso na densidade mineral óssea (DMO) de adolescentes obesos submetidos a intervenção com base em dieta hipocalórica e orientações durante nove meses. MÉTODOS: Realizaram-se avaliações da antropometria, da composição corporal, da DMO e do consumo alimentar. RESULTADOS: Participaram do estudo 55 adolescentes, 78,2% meninas, com média de 16,6 (1,4) anos. Destes, 44,4% não apresentaram redução do peso. O grupo que respondeu à intervenção apresentou média de perda de peso de 6,2% (4,6) do peso inicial. Houve aumento significativo da DMO e conteúdo mineral ósseo (CMO) entre os adolescentes não-respondedores e aumento do CMO e área óssea entre os respondedores, associados, principalmente, com as alterações da composição corporal com o ganho ou a perda de peso. CONCLUSÃO: O aumento da massa óssea mesmo com a perda de peso demonstrou que o emagrecimento não ter efeito negativo do emagrecimento e denota provável contribuição da melhora dos hábitos alimentares na aquisição óssea de adolescentes.Universidade de São Paulo Faculdade de Saúde Pública Departamento de NutriçãoUniversidade Federal de São Paulo (UNIFESP) Centro de Atendimento e Apoio ao AdolescenteUNIFESP Disciplina de EndocrinologiaUNIFESP, Centro de Atendimento e Apoio ao AdolescenteUNIFESP, Disciplina de EndocrinologiaSciEL

Misreporting of dietary energy intake in adolescents

OBJECTIVES: To examine the prevalence of under and overreporting of energy intake in adolescents and their associated factors. METHODS: Cross-sectional study with 96 postpubertal adolescents (47 normal-weight and 49 obese), mean age of 16.6±1.3 years. Weight and height were measured, and body mass index was calculated. Body composition was assessed by dual energy X-ray absorptiometry. Dietary intake was evaluated by a 3-day dietary record. Biochemical assessment was performed (serum total cholesterol, LDL-cholesterol, HDL-cholesterol, plasma glucose, and insulin). Underreporters reported energy intake 2.4 x BMR. RESULTS: Energy intake misreporting (under or overreporting) was identified in 65.6% of adolescents (64.6 and 1% of under and overreporting, respectively). Obese adolescents were 5.0 times more likely to underreport energy intake (95%CI 2.0-12.7) than normal-weight participants. Underreporters showed higher rates of insufficient intake of carbohydrate (19.3 vs. 12.1%, p = 0.046) and lipids (11.3 vs. 0%, p 2,4 x TMB. RESULTADOS: Notificação imprecisa (sub ou supernotificação) da ingestão energética foi identificada em 65,6% dos adolescentes (64,6 e 1% de sub e supernotificação, respectivamente). Os adolescentes obesos apresentaram 5.0 vezes mais chances de subnotificar a ingestão energética (IC95% 2,0-12,7) do que os participantes com peso normal. Os subnotificadores apresentaram taxas mais altas de ingestão insuficiente de carboidratos (19,3 versus 12,1%, p = 0,046) e de lipídios (11,3 versus 0%, p < 0,001) do que os notificadores plausíveis. A ingestão de colesterol também foi mais baixa entre os subnotificadores (p = 0,017). Não houve diferenças significativas na composição corporal e nos parâmetros bioquímicos em relação à notificação imprecisa. CONCLUSÕES: Os resultados obtidos demonstraram alta porcentagem de notificação imprecisa da ingestão energética entre adolescentes, principalmente entre os obesos, o que sugere que os valores de consumo de nutrientes ajustado para o consumo de energia deveriam ser empregados na análise de risco da relação dieta-doença a fim de contribuir para a redução de erros associados à notificação imprecisa.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de Minas Gerais Departamento de Enfermagem Materno-Infantil e Saúde PúblicaUniversidade Federal de São Paulo (UNIFESP) Centro de Atendimento e Apoio ao AdolescenteUNIFESP Centro de Atendimento e Apoio ao AdolescenteUniversidade de São Paulo Faculdade de Saúde Pública Departamento de NutriçãoUNIFESP, Centro de Atendimento e Apoio ao AdolescenteUNIFESP, Centro de Atendimento e Apoio ao AdolescenteSciEL

Cálculo do Tempo de Execução de Códigos no Pior Caso (WCET) em Aplicações de Tempo Real: Um Estudo de Caso

O WCET vem sendo estudado há poucos anos por pesquisadores da área de sistemas de tempo real para tentar melhorar ou minimizar os defeitos ocorridos em aplicações de tempo real. Uma vez que, o WCET aprofunda-se a nível de hardware e software, fazendo cálculos em aplicações de baixo nível. Logo, este trabalho tem como principais objetivos, dar uma visão geral sobre o que seria WCET, apresentar as principais técnicas para se fazer o cálculo da análise de fluxo, apresentar os componentes da análise estática e contribuir para disseminação do assunto

Use of manganese oxides recovered from spent batteries in electrocatalysis of oxygen reduction reaction in alkaline medium

The oxygen reduction reaction was studied in alkaline media using manganese oxides obtained from spent batteries as electrocatalysts. Three processes were used to recover manganese oxides from spent batteries. The particles obtained were in the range from 8 to 11 nm. The electrochemical experiments indicated a good electrocatalytic activity toward oxygen reduction using the different samples and showing approximately a direct transference of 4 electrons during the process. Even though all the processes were efficient, the best result was observed for the prepared sample using reactants of low cost.FAPESPCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)UFAB

Pt-Decorated TiO2 Materials Supported on Carbon : Increasing Activities and Stabilities toward the ORR by Tuning the Pt Loading

Pt nanoparticles (Pt NPs) supported on carbon have been widely employed as electrocatalysts toward oxygen reduction reaction. The development of more efficient electrocatalysts that enable one to reduce or even not require the use of Pt is a central challenge. In addition to the control over the physical and chemical features of Pt NPs, metal support interactions can be employed to enhance activities via the generation and exposure of surface-active sites. In this context, we report herein the development of electrocatalysts composed of Pt NPs supported on TiO2 microspheres, that were subsequently impregnated onto carbon. We have found that, by optimizing the loading of Pt at the TiO2 surface, the electrocatalytic activity toward the ORR could be improved compared to that of the commercial Pt/C (E-TEK) material, even at lower Pt loadings. The enhancement in activities could be assigned to the balance between Pt loading and generation of reactive surface sites, such as adsorbed oxygenated species. Moreover, the utilization of TiO2 as support enabled improved stabilities relative to Pt/C (E-TEK). We believe that the results described herein may inspire the development of electrocatalysts for the ORR with improved activities and stabilities.Peer reviewe

The association between the neutrophil-to-lymphocyte ratio and mortality in critical illness: an observational cohort study

Introduction The neutrophil-to-lymphocyte ratio (NLR) is a biological marker that has been shown to be associated with outcomes in patients with a number of different malignancies. The objective of this study was to assess the relationship between NLR and mortality in a population of adult critically ill patients. Methods We performed an observational cohort study of unselected intensive care unit (ICU) patients based on records in a large clinical database. We computed individual patient NLR and categorized patients by quartile of this ratio. The association of NLR quartiles and 28-day mortality was assessed using multivariable logistic regression. Secondary outcomes included mortality in the ICU, in-hospital mortality and 1-year mortality. An a priori subgroup analysis of patients with versus without sepsis was performed to assess any differences in the relationship between the NLR and outcomes in these cohorts. Results A total of 5,056 patients were included. Their 28-day mortality rate was 19%. The median age of the cohort was 65 years, and 47% were female. The median NLR for the entire cohort was 8.9 (interquartile range, 4.99 to 16.21). Following multivariable adjustments, there was a stepwise increase in mortality with increasing quartiles of NLR (first quartile: reference category; second quartile odds ratio (OR) = 1.32; 95% confidence interval (CI), 1.03 to 1.71; third quartile OR = 1.43; 95% CI, 1.12 to 1.83; 4th quartile OR = 1.71; 95% CI, 1.35 to 2.16). A similar stepwise relationship was identified in the subgroup of patients who presented without sepsis. The NLR was not associated with 28-day mortality in patients with sepsis. Increasing quartile of NLR was statistically significantly associated with secondary outcome. Conclusion The NLR is associated with outcomes in unselected critically ill patients. In patients with sepsis, there was no statistically significant relationship between NLR and mortality. Further investigation is required to increase understanding of the pathophysiology of this relationship and to validate these findings with data collected prospectively.National Institutes of Health (U.S.) (Grant R01 EB017205-01A1

Exact multipoint and multitime correlation functions of a one-dimensional model of adsorption and evaporation of dimers

In this work, we provide a method which allows to compute exactly the multipoint and multi-time correlation functions of a one-dimensional stochastic model of dimer adsorption-evaporation with random (uncorrelated) initial states. In particular explicit expressions of the two-point noninstantaneous/instantaneous correlation functions are obtained. The long-time behavior of these expressions is discussed in details and in various physical regimes.Comment: 6 pages, no figur