Search results for "POPULATION"
showing 10 items of 9945 documents
Invasive Alien Species and Their Effects on Marine Animal Forests
2020
Nonindigenous species are increasingly transported around the world through multiple pathways by a diversity of vectors. Invasive species are a subset of those that are introduced into the receptor community, where they establish and increase their population to a size where they impact the native system. Marine invasive species can therefore interact with and modify native animal forests and/or create novel ones resulting in simple-to-complex changes in material cycling, energy flow, ecosystem structure, and function. Despite the ever increasing number of studies dealing with marine invasive species, mostly biological invasions are mentioned generically as one of a number of threats of dir…
Modernizando la nación : Democracia y autoritarismo en el comité fílmico de la industria petrolera (Venezuela, 1947-1951)
2020
Tras la reforma petrolera de 1943, las compañías petroleras transnacionales con intereses en Venezuela se alinearon con el nacionalismo moderado de las nuevas élites gobernantes y se presentaron como indispensables para el progreso de la nación. Para esto, establecieron departamentos de relaciones públicas, programas de responsabilidad social y de mecenazgo cultural (Tinker Salas, 2009). En este contexto, también crearon programas fílmicos destinados a su fuerza laboral y al público venezolano. El primero de estos programas fue el Comité Fílmico de la Industria Petrolera (1947-1951). Enfocando este programa fílmico desde la categoría cine empresarial, propuesta por Hediger y Vonderau (2009a…
Expert system for predicting unstable angina based on Bayesian networks
2013
The use of computer-based clinical decision support (CDS) tools is growing significantly in recent years. These tools help reduce waiting lists, minimise patient risks and, at the same time, optimise the cost health resources. In this paper, we present a CDS application that predicts the probability of having unstable angina based on clinical data. Due to the characteristics of the variables (mostly binary) a Bayesian network model was chosen to support the system. Bayesian-network model was constructed using a population of 1164 patients, and subsequently was validated with a population of 103 patients. The validation results, with a negative predictive value (NPV) of 91%, demonstrate its …
Generating a Located Synthetic Population of Individuals, Households, and Dwellings
2017
Some of the new approaches in urban modeling, such as multi-agent systems (MAS) or activity-based models (ABM), require inputs in the form of disaggregated individual data. But for privacy protection reasons, such data is seldom available at this level. One way to get around this obstacle is to generate a synthetic population. This paper presents a method for generating a population from fully aggregated socio-demographic and geographic data. Based on French examples, this method can be reproduced anywhere in the country providing a relevant linkage between the characteristics of agents and those of urban spaces. The proposed method is subdivided into two steps. First, a population of agent…
Long-term decrease in sex-specific natural mortality of European lobster within a marine protected area
2013
Marine protected areas (MPAs) and marine reserves hold promise as tools for nature conservation and fisheries management, but data on long-term demographic effects are still sparse. Here, we use a unique capture-mark-recapture data set from Kavra, an MPA on the west coast of Sweden where fishing for European lobster Homarus gammarus has been banned since 1989, to directly quantify annual survival probabilities in the absence of harvest mortality. The non-migratory behaviour of this species allowed multiple recaptures and releases of a large num- ber of individuals within the MPA. We found strong evidence for a long-term decrease in sex - specific natural mortality throughout the study perio…
First-principles calculations on surface hydroxyl impurities in BaF2
2012
Abstract OH − impurities located near the (1 1 1) BaF 2 surface have been studied by using density functional theory (DFT) with hybrid exchange potentials, namely DFT-B3PW. Twenty surface OH − configurations were studied, and the hydroxyls located on the first surface layer are the energetically most favorable configurations. For the (1 1 1) BaF 2 surface atomic layers, the surface hydroxyls lead to a remarkable XY -translation and a dilating effect in the Z -direction, overcoming the surface shrinking effect in the perfect slab. Bond population analysis shows that the surface effect strengthens the covalency of surface OH − impurities. The studies on band structures and density of states (…
Calculation of the conformational dependence of valence and Rydberg states in n-tetrasilane
1999
Abstract Previous CIS/6-31G ∗∗ and CASSCF/6-31G ∗ calculations of valence excited states of n -tetrasilane accounted qualitatively for the observed conformational dependence of condensed-phase UV absorption spectra. In an attempt to understand this result, we have performed CIS calculations with a larger basis set (MC-311G(2d) on Si, 6-311G on H, and 2s, 2p, and 2d diffuse orbitals at molecular center of mass). The first two excited states are of valence character at all dihedral angles if the molecule is isolated. When it is embedded in a rare gas cluster, the lowest four states are of valence character, and the results are nearly identical with those obtained without diffuse orbitals in t…
Well-being and demographic dynamics
2012
This paper presents a socio-demographic model defined by sexes and structured by age. The model is a von Foerster-McKendrick model for the dynamics of population by sex and age of a general human population. The fertility and deaths rates are structured by age and they depend on the well-being variable. The well-being variable is defined by UN, HDI-Hybrid. We present the validation of the stochastic formulation model from the case of Spain in the period 2003–2008.
A New Multinomial Accuracy Measure for Polling Bias
2014
In this article, we propose a polling accuracy measure for multi-party elections based on a generalization of Martin, Traugott, and Kennedy's two-party predictive accuracy index. Treating polls as random samples of a voting population, we first estimate an intercept only multinomial logit model to provide proportionate odds measures of each party's share of the vote, and thereby both unweighted and weighted averages of these values as a summary index for poll accuracy. We then propose measures for significance testing, and run a series of simulations to assess possible bias from the resulting folded normal distribution across different sample sizes, finding that bias is small even for polls…
Cardiovascular diseases and HCV infection: a simple association or more?
2013
HCV infection, metabolic disorders and cardiovascular alterations, considered alone or in combination, are common conditions in a large proportion of the general population. Consequently, determining whether the association of HCV infection with cardiometabolic disorders is simply coincidental or, conversely, caused by pathogenetic mechanisms (in)directly linking chronic HCV infection to these disorders, would be of extreme relevance. Several clinical studies have shown that metabolic disorders—namely, type 2 diabetes,1 insulin resistance (IR)2 and hepatic steatosis3—are highly prevalent in patients with chronic hepatitis C (CHC) compared with non-infected patients. Experimental and clinica…