Optimal Design of Robust Combinatorial Mechanisms for Substitutable Goods

In this paper we consider multidimensional mechanism design problem for selling discrete substitutable items to a group of buyers. Previous work on this problem mostly focus on stochastic description of valuations used by the seller. However, in certain applications, no prior information regarding buyers' preferences is known. To address this issue, we consider uncertain valuations and formulate the problem in a robust optimization framework: the objective is to minimize the maximum regret. For a special case of revenue-maximizing pricing problem we present a solution method based on mixed-integer linear programming formulation

Formação em serviço: impacto de novas estratégias

A formação em enfermagem contribui para o desenvolvimento de competências cognitivas e técnicas, mas também relacionais que possam ser transferíveis para o contexto de trabalho pelo que se deve privilegiar a formação em serviço como forma de manter actualizados, aprofundar e desenvolver os conhecimentos adquiridos. Faz parte do descritivo de funções do enfermeiro e consta dos seus princípios orientadores da prática, a constante actualização através da formação. (ver OE ….) Identificada a irregular e reduzida formação interna que ocorre no serviço (obrigatória ou não), a par de identificação de lacunas em temas fulcrais, foi implementada no serviço de Cardiologia do Hospital Fernando Fonseca E.P.E. múltiplas estratégias de intervenção que visem o desenvolvimento profissional dos enfermeiros e auxiliares de acção médica através do aumento da formação na sua globalidade. A diversas estratégias preconizadas consistem na contabilização das horas de formação como horas de serviço, inscrição dos formandos para as formações com disponibilização do dia expresso em horário, possibilidade de negociação de objectivos para as avaliações de desempenho anuais, existência de um cronograma anual, de um Manual do Formador como guia orientador à prática formativa, abordagem de diferentes áreas focado nas necessidades de serviço e também no interesse individual, com apresentações frequentes e que abranja todos os profissionais, formações semanais de curta duração a decorrer em passagem de turno, formações mensais de uma hora em sala de formação, trabalhos disponibilizados a toda a equipa. Esta etapa formativa decorreu ao longo de todo o ano de 2014, cabendo em fase posterior, a sua análise e avaliação, com base em indicadores de formação em serviço, como sendo indicadores de execução como a taxa de número de horas de formação e taxa de número de acções de formação, acrescida da avaliação de satisfação individual dos participantes e suas opiniões face às estratégias implementadas, através da realização de questionários aos mesmos. Acresce a avaliação da variação de adesão à formação não obrigatória face às formações disponibilizadas, comparativamente com as obrigatórias realizadas face à totalidade de formação obrigatórias. A análise dos referidos dados, revelam-nos uma percentagem significativa de acções de formação ocorridas, assim como elevado número de horas formativas, pelo que sugere um método eficaz de acção. Uma análise preliminar revela satisfação e interesse equiparados às taxas formativas. Daqui se poderá depreender que o conjunto de estratégias implementadas veio ao encontro dos objectivos estabelecidos. Cabe, em fase posterior, a análise do impacto formativo na melhoria das práticas, eventualmente com base em indicadores adequados a cada formação, complementada com os dados trimestrais das auditorias aos cuidados de enfermagem do HFF

The temporal representation of experience in subjective mood

Humans refer to their mood state regularly in day-to-day as well as clinical interactions. Theoretical accounts suggest that when reporting on our mood we integrate over the history of our experiences; yet, the temporal structure of this integration remains unexamined. Here, we use a computational approach to quantitatively answer this question and show that early events exert a stronger influence on reported mood (a primacy weighting) compared to recent events. We show that a Primacy model accounts better for mood reports compared to a range of alternative temporal representations across random, consistent, or dynamic reward environments, different age groups, and in both healthy and depressed participants. Moreover, we find evidence for neural encoding of the Primacy, but not the Recency, model in frontal brain regions related to mood regulation. These findings hold implications for the timing of events in experimental or clinical settings and suggest new directions for individualized mood interventions

Ultra-processed food consumption and obesity in the Australian adult population

Background: Rapid simultaneous increases in ultra-processed food sales and obesity prevalence have been observed worldwide, including in Australia. Consumption of ultra-processed foods by the Australian population was previously shown to be systematically associated with increased risk of intakes of nutrients outside levels recommended for the prevention of obesity. This study aims to explore the association between ultra-processed food consumption and obesity among the Australian adult population and stratifying by age group, sex and physical activity level. Methods: A cross-sectional analysis of anthropometric and dietary data from 7411 Australians aged ≥20 years from the National Nutrition and Physical Activity Survey 2011–2012 was performed. Food consumption was evaluated through 24-h recall. The NOVA system was used to identify ultra-processed foods, i.e. industrial formulations manufactured from substances derived from foods and typically added of flavours, colours and other cosmetic additives, such as soft drinks, confectionery, sweet or savoury packaged snacks, microwaveable frozen meals and fast food dishes. Measured weight, height and waist circumference (WC) data were used to calculate the body mass index (BMI) and diagnosis of obesity and abdominal obesity. Regression models were used to evaluate the association of dietary share of ultra-processed foods (quintiles) and obesity indicators, adjusting for socio-demographic variables, physical activity and smoking. Results: Significant (P-trend ≤ 0.001) direct dose–response associations between the dietary share of ultra-processed foods and indicators of obesity were found after adjustment. In the multivariable regression analysis, those in the highest quintile of ultra-processed food consumption had significantly higher BMI (0.97 kg/m2; 95% CI 0.42, 1.51) and WC (1.92 cm; 95% CI 0.57, 3.27) and higher odds of having obesity (OR = 1.61; 95% CI 1.27, 2.04) and abdominal obesity (OR = 1.38; 95% CI 1.10, 1.72) compared with those in the lowest quintile of consumption. Subgroup analyses showed that the trend towards positive associations for all obesity indicators remained in all age groups, sex and physical activity level. Conclusion: The findings add to the growing evidence that ultra-processed food consumption is associated with obesity and support the potential role of ultra-processed foods in contributing to obesity in Australia

Rationale, design, and analysis of combined Brazilian household budget survey and food intake individual data

<p>Abstract</p> <p>Background</p> <p>Data on food intake at the individual level and its statistical distribution in population groups defined by age, gender, or geographic areas are important in planning public health and nutrition programs. However, individual-based surveys in representative population samples are expensive to perform.</p> <p>Methods/Design</p> <p>In Brazil, an individual based survey is under consideration to be conducted alongside the household budget survey (HBS), which will be carried out in 2008–2009. This paper presents the methodological framework of dietary data collection and indicates the directions to combining both sources of data.</p> <p>The 2008–2009 Brazilian HBS sample will include 60,000 households. Of the selected HBS households, 30% will be randomly sampled to gather data on individual food intake. Therefore, individual dietary intake data is expected to be gathered for 70,000 individuals. Data collection procedures will comprise: completion of a diary with information regarding food purchases during a seven-day period; registration of all items consumed during two non-consecutive days for all 10 year-old or older members of the household. The sample will be large enough to capture the variation between individuals, and the two records will assure the estimation of the variation within individuals for food groups, energy and nutrients. Data on individual dietary intake and food family budget will be stratified by the five regions of the country and by rural or urban. A pilot study has been conducted in two states, and it indicated that combining individual and budgetary data in a survey is feasible.</p> <p>Discussion</p> <p>This kind of study will allow us to estimate correlations between individual intake and household purchases, overcoming the limitations of individual dietary surveys, and enhancing the HBS with information on eating out and intra-familiar distribution of food.</p

Spectral weight transfer in a disorder-broadened Landau level

In the absence of disorder, the degeneracy of a Landau level (LL) is $N=BA/\phi_0$, where $B$ is the magnetic field, $A$ is the area of the sample and $\phi_0=h/e$ is the magnetic flux quantum. With disorder, localized states appear at the top and bottom of the broadened LL, while states in the center of the LL (the critical region) remain delocalized. This well-known phenomenology is sufficient to explain most aspects of the Integer Quantum Hall Effect (IQHE) [1]. One unnoticed issue is where the new states appear as the magnetic field is increased. Here we demonstrate that they appear predominantly inside the critical region. This leads to a certain ``spectral ordering'' of the localized states that explains the stripes observed in measurements of the local inverse compressibility [2-3], of two-terminal conductance [4], and of Hall and longitudinal resistances [5] without invoking interactions as done in previous work [6-8].Comment: 5 pages 3 figure

Early detection of left ventricular diastolic dysfunction in Chagas' disease

BACKGROUND: Chagas' disease may cause left ventricular diastolic dysfunction and its early detection in asymptomatic patients would allow to stratify the risk and to optimize medical treatment. The aim of this study is to investigate if transmitral Doppler flow can detect early abnormalities of the diastolic left ventricular function in patients during the indeterminate phase of Chagas' disease, in which the electrocardiogram (ECG), chest x-ray and 2-D echocardiogram (2D-echo) are normal. METHODS: a group of 54 patients with Chagas' disease was studied and compared to a control group of 27 subjects of similar age. All were assessed with an ECG, chest X-ray, 2-D echo, and transmitral Doppler flow. RESULTS: both groups had similar values in the 2D-echo. In patients with Chagas' disease, the transmitral Doppler showed a higher peak A velocity (control group: 0.44 m/sec, Chagas group: 0.55 m/sec, p = 0.001), a lower E/A ratio (control group: 1.45, Chagas group: 1.22, p < 0.05), and a lengthening of the deceleration time of early diastolic filling (control: 138.7 ± 26.8 msec, Chagas group: 167.9 ± 34.6 msec, p = 001), thus revealing an early disorder of the diastolic left ventricular function in patients with Chagas' disease. CONCLUSION: in patients with Chagas' disease who are in the indeterminate phase, transmitral Doppler flow allowed to identify early abnormalities of the left ventricular diastolic function, which provide useful clinical information for prognostic stratification and treatment

Gestational age influences the early microarchitectural changes in response to mechanical ventilation in the preterm lamb lung

Background: Preterm birth is associated with abnormal lung architecture, and a reduction in pulmonary function related to the degree of prematurity. A thorough understanding of the impact of gestational age on lung microarchitecture requires reproducible quantitative analysis of lung structure abnormalities. The objectives of this study were (1) to use quantitative histological software (ImageJ) to map morphological patterns of injury resulting from delivery of an identical ventilation strategy to the lung at varying gestational ages and (2) to identify associations between gestational age-specific morphological alterations and key functional outcomes. Method: Lung morphology was compared after 60 min of a standardized ventilation protocol (40 cm H2O sustained inflation and then volume-targeted positive pressure ventilation with positive end-expiratory pressure 8 cm H2O) in lambs at different gestations (119, 124, 128, 133, 140d) representing the spectrum of premature developmental lung states and the term lung. Age-matched controls were compared at 124 and 128d gestation. Automated and manual functions of Image J were used to measure key histological features. Correlation analysis compared morphological and functional outcomes in lambs aged ≤128 and >128d. Results: In initial studies, unventilated lung was indistinguishable at 124 and 128d. Ventilated lung from lambs aged 124d gestation exhibited increased numbers of detached epithelial cells and lung tissue compared with 128d lambs. Comparing results from saccular to alveolar development (120-140d), lambs aged ≤124d exhibited increased lung tissue, average alveolar area, and increased numbers of detached epithelial cells. Alveolar septal width was increased in lambs aged ≤128d. These findings were mirrored in the measures of gas exchange, lung mechanics, and molecular markers of lung injury. Correlation analysis confirmed the gestation-specific relationships between the histological assessments and functional measures in ventilated lambs at gestation ≤128 vs. >128d.Conclusion: Image J allowed rapid, quantitative assessment of alveolar morphology, and lung injury in the preterm lamb model. Gestational age-specific patterns of injury in response to delivery of an identical ventilation strategy were identified, with 128d being a transition point for associations between morphological alterations and functional outcomes. These results further support the need to develop individualized respiratory support approaches tailored to both the gestational age of the infant and their underlying injury response

Psychological morbidity as a moderator of intention to quit smoking : a study of smokers and former smokers

Objective: To analyze psychological morbidity as a moderator of the relationship between smoking representations and quality of life in smokers and former smokers, as well as to determine which psychological variables discriminate between smokers with and without the intention to quit smoking. Methods: This was a quantitative, correlational cross-sectional study involving a convenience sample of 224 smokers and 169 former smokers. Results: In smokers and former smokers, psychological morbidity had a moderating effect on the relationship between mental/physical quality of life and smoking representations (cognitive representations, emotional representations, and comprehensibility). Smokers with the intention to quit smoking more often presented with low comprehensibility, threatening emotional representations, behavioral beliefs, and perceived behavioral control, as well as with normative/control beliefs, than did those without the intention to quit. Conclusions: The results of this study underscore the importance of the moderating effect exerted by psychological morbidity, as well as that of sociocognitive variables, among smokers who have the intention to quit smoking.ResumoObjetivo: Analisar a morbidade psicológica como um moderador na relação entre as representações do tabaco e a qualidade de vida em fumantes e ex-fumantes, assim como conhecer as variáveis psicológicas que discriminam os fumantes com e sem intenção para deixar de fumar. Métodos: Estudo quantitativo, correlacional e transversal com uma amostra de conveniência constituída por 224 fumantes e 169 ex-fumantes. Resultados: Verificou-se um efeito moderador da morbidade psicológica na relação entre a qualidade de vida (física e mental) e as representações do tabaco (representações cognitivas e emocionais e compreensão) nos fumantes e nos ex-fumantes. Os fumantes com intenção para deixar de fumar apresentavam menor compreensão, representações emocionais mais ameaçadoras, mais crenças de comportamento, maior controle comportamental percebido e mais crenças normativas/controle do que aqueles sem essa intenção. Conclusões: Os resultados deste estudo enfatizam a importância da morbidade psicológica como moderadora, bem como das variáveis sociocognitivas, junto dos fumantes que querem deixar de fumar