Search results for "valence"
showing 10 items of 2732 documents
Incidence and prevalence of amyotrophic lateral sclerosis in Sicily: a population based study
2008
Epidemiology of congenital diaphragmatic hernia in Europe: a register-based study.
2015
INTRODUCTION: Published prevalence rates of congenital diaphragmatic hernia (CDH) vary. This study aims to describe the epidemiology of CDH using data from high-quality, population-based registers belonging to the European Surveillance of Congenital Anomalies (EUROCAT).METHODS: Cases of CDH delivered between 1980 and 2009 notified to 31 EUROCAT registers formed the population-based case series. Prevalence over time was estimated using multilevel Poisson regression, and heterogeneity between registers was evaluated from the random component of the intercept.RESULTS: There were 3373 CDH cases reported among 12 155 491 registered births. Of 3131 singleton cases, 353 (10.4%) were associated wit…
Epidemiology of eating disorders in Latin America: a systematic review and meta-analysis.
2016
Purpose of reviewEating disorders are currently not considered to be limited to Western culture. We systematically reviewed the existing literature on the prevalence of eating disorders in Latin America.Recent findingsOf 1583 records screened, 17 studies from Argentina, Brazil, Chile, Colombia, Mexico, and Venezuela were included in the analysis. Most studies reported point-prevalence rates and only three studies provided lifetime and 12-month prevalence rates. We found a mean point-prevalence rate of 0.1% for anorexia nervosa, 1.16% for bulimia nervosa, and 3.53% for binge-eating disorder (BED) in the general population. Heterogeneity for bulimia nervosa and BED was large. This meta-analys…
Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome: Insights from the LUNG SAFE study
2020
Abstract Background Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence o…
Electronic structure of phthalocyanines : Theoretical investigation of the optical properties of phthalocyanine monomers, dimers, and crystals
1990
We present valence effective Hamiltonian (VEH) calculations on the optical absorptions of a series of phthalocyanine compounds: the metal‐free phthalocyanine molecule, a model system for the lithium phthalocyanine molecule, the metal‐free phthalocyanine dimer, and model systems for the lutetium diphthalocyanine and the lithium phthalocyanine crystal. For these compounds, it is found that the major factor influencing the evolution of the optical transitions is not the electronic structure of the metal but rather the geometric structure: phthalocyanine intraring geometry and, in the dimers and crystals, interring separation and staggering angle. The origin of the so‐called Soret or B absorpti…
Appetite for destruction: A psychometric examination and prevalence estimation of destructive leadership in Sweden
2021
There is a growing awareness that destructive leadership has a significant negative impact on employe outcomes. However, little is known about the content and dimensionality of this multidimensional concept, and there are few reliable measures available for organizations and researchers to evaluate these behaviors. Based on a representative sample (N = 1132) of the Swedish workforce, the aim of this study is threefold: first, to examine the factor structure and validity of an easy-to-use multidimensional destructive leadership measure (Destrudo-L)in the general Swedish work context; second, to identify destructive leadership profiles using latent profile analysis (LPA), and determine in wha…
Optical absorption of divalent metal tungstates: Correlation between the band-gap energy and the cation ionic radius
2008
We have carried out optical-absorption and reflectance measurements at room temperature in single crystals of AWO4 tungstates (A = Ba, Ca, Cd, Cu, Pb, Sr, and Zn). From the experimental results their band-gap energy has been determined to be 5.26 eV (BaWO4), 5.08 eV (SrWO4), 4.94 eV (CaWO4), 4.15 eV (CdWO4), 3.9-4.4 eV (ZnWO4), 3.8-4.2 eV (PbWO4), and 2.3 eV (CuWO4). The results are discussed in terms of the electronic structure of the studied tungstates. It has been found that those compounds where only the s electron states of the A2+ cation hybridize with the O 2p and W 5d states (e.g BaWO4) have larger band-gap energies than those where also p, d, and f states of the A2+ cation contribu…
Drug resistance patterns of bacteria isolated from patients with nosocomial pneumonia at Tehran hospitals during 2009-2011
2013
Introduction: Nosocomial pneumonia remains an important cause of mortality and morbidity worldwide. Surveillance programs play an important role in the identification of common etiologic agents and local patterns of antimicrobial resistance. Methodology: In this study we determined the frequency and antimicrobial susceptibility of pathogens isolated from patients with nosocomial pneumonia during 2009 to 2011. Results: A total of 642 bacteria were isolated from 516 suspected samples. Acinetobacter baumannii (21.1%, n = 136), was the commonest isolated pathogen followed by Pseudomonas aeruginosa (17.4%, n = 112) , Staphylococcus aureus (15.8%, n = 102) and enterococci (8.4% n = 54). The most …
Fatal measles as AIDS presentation in Italy
2019
El fenómeno del sexting entre los adolescentes españoles: prevalencia, actitudes, motivaciones y variables explicativas
2020
Resumen: El sexting es un fenómeno que consiste en el envío y la recepción de fotos, videos y/o mensajes de texto de naturaleza sexual a través de smartphones. Como en todos los demás países desarrollados, se está convirtiendo en una práctica cada vez más popular entre los adolescentes de España. Al tratarse de un fenómeno muy reciente todavía no existen muchos trabajos que hayan estudiado con profundidad su entidad y sus factores implicados. Por tanto, los dos objetivos de este estudio fueron determinar la prevalencia y analizar las variables explicativas del inicio y del mantenimiento de las conductas de sexting. La muestra estuvo formada por 784 adolescentes españoles (52% chicos y 48% c…