997 resultados para 123-766
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Classical treatments of problems of sequential mate choice assume that the distribution of the quality of potential mates is known a priori. This assumption, made for analytical purposes, may seem unrealistic, opposing empirical data as well as evolutionary arguments. Using stochastic dynamic programming, we develop a model that includes the possibility for searching individuals to learn about the distribution and in particular to update mean and variance during the search. In a constant environment, a priori knowledge of the parameter values brings strong benefits in both time needed to make a decision and average value of mate obtained. Knowing the variance yields more benefits than knowing the mean, and benefits increase with variance. However, the costs of learning become progressively lower as more time is available for choice. When parameter values differ between demes and/or searching periods, a strategy relying on fixed a priori information might lead to erroneous decisions, which confers advantages on the learning strategy. However, time for choice plays an important role as well: if a decision must be made rapidly, a fixed strategy may do better even when the fixed image does not coincide with the local parameter values. These results help in delineating the ecological-behavior context in which learning strategies may spread.
Exact asymptotics and limit theorems for supremum of stationary chi-processes over a random interval
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We have taken advantage of the natural milieu of matched pair of azole sensitive (AS) and azole resistant (AR) clinical isolates of Candida glabrata for expressing its major ABC multidrug transporter, CgCdr1p for structure and functional analysis. This was accomplished by tagging a green fluorescent protein (GFP) downstream of ORF of CgCDR1 and integrating the resultant fusion protein at its native chromosomal locus in AS and AR backgrounds. The characterization confirmed that in comparison to AS isolate, CgCdr1p-GFP was over-expressed in AR isolates due to its hyperactive native promoter and the GFP tag did not affect its functionality in either construct. We observed that in addition to Rhodamine 6 G (R6G) and Fluconazole (FLC), a recently identified fluorescent substrate of multidrug transporters Nile Red (NR) could also be expelled by CgCdr1p. Competition assays with these substrates revealed the presence of overlapping multiple drug binding sites in CgCdr1p. Point mutations employing site directed mutagenesis confirmed that the role played by unique amino acid residues critical to ATP catalysis and localization of ABC drug transporter proteins are well conserved in C. glabrata as in other yeasts. This study demonstrates a first in vivo novel system where over-expression of GFP tagged MDR transporter protein can be driven by its own hyperactive promoter of AR isolates. Taken together, this in vivo system can be exploited for the structure and functional analysis of CgCdr1p and similar proteins wherein the artefactual concerns encountered in using heterologous systems are totally excluded.
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La herramienta de monitorización de clusters MoniTo debe estar preparada ante los constantes cambios en el kernel de Linux que la pudieran dejar inutilizable. Para evitarlo se ha modificado su implementación utilizando librerías Libgtop. También se ha modificado su interfaz web para adaptarla a los nuevos tiempos, optimizar su funcionamiento y dotarla de nuevas posibilidades.
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Mécénat texte imprimé : Cet ouvrage a été numérisé grâce à Jacques Houbert
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Annaul report for Iowa Workforce Development in PDF adn ADA Compliant Text File
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Escitalopram is a serotonin reuptake inhibitor prescribed for depression and anxiety. There is a paucity of information regarding safety in pregnancy. The objective of this study was to determine whether escitalopram is associated with an increased risk for major malformations or other adverse outcomes following use in pregnancy. The authors analyzed pregnancy outcomes in women exposed to escitalopram (n = 212) versus other antidepressants (n = 212) versus nonteratogenic exposures (n = 212) and compared the outcomes. Among the escitalopram exposures were 172 (81%) live births, 32 (15%) spontaneous abortions, 6 (2.8%) therapeutic abortions, 3 stillbirths (1.7%), and 3 major malformations (1.7%). The only significant differences among groups was the rate of low birth weight (<2500 g) and overall mean birth weight (P = .225). However, spontaneous abortion rates were higher in both antidepressant groups (15% and 16%) compared with controls (8.5%; P = .066). There were lower rates of live births (P = .006), lower overall birth weight (P < .001), and increased rates of low birth weight (<2500 g; P = .009) with escitalopram. Spontaneous abortion rates were nearly double in both antidepressant groups (15% and 16%) compared with controls (8.5%) but not significant (P = .066). Escitalopram does not appear to be associated with an increased risk for major malformations but appears to increase the risk for low birth weight, which was correlated with the increase in infants weighing <2500 g. In addition, the higher rates of spontaneous abortions in both antidepressant groups confirmed previous findings.
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High altitude constitutes an exciting natural laboratory for medical research. Over the past decade, high-altitude studies have provided important new insight into the regulation of the pulmonary circulation. Studies in high-altitude pulmonary edema (HAPE)-prone subjects, a condition characterized by exaggerated hypoxic pulmonary hypertension, have provided evidence for the central role of pulmonary vascular endothelial and respiratory epithelial nitric oxide for pulmonary artery pressure homeostasis. Studies of healthy and maladapted high-altitude dwellers have provide important new insight into mechanisms conferring protection against/predisposing to pulmonary hypertension. Finally, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary (and systemic) vascular dysfunction at an early stage. Here, we will summarize recent studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning pulmonary hypertension and to the first direct demonstration of fetal programming of pulmonary vascular dysfunction in humans.
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This paper addresses the migration behaviours of young university graduates from a rural region in Switzerland. Based on a questionnaire survey, it compares graduates' current place of residence (i.e. whether or not they returned to their home region) with characteristics related to their socio-familial, migration and professional trajectories. The propensity to return varies not only according to labour market variables (employment opportunities), but also to other factors, some of which have even more influence than job opportunities. The graduates' life course position (kind of household), their partners' characteristics (level of education and home region) and their family background (socio-economic status and history of migration) all play a central role. On the whole, results show that migration appears as a selective and complex process embedded in the life course of graduates.
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Recommendations on preventive services rarely mention how to apply them to older people. Even though general criteria (prevalence of disease, quality of screening tests) that influence screening's efficacy remain important, appropriateness of screening in older persons depends much more on individual criteria, such as comorbidity, functional status, and life expectancy. More than with any other age group, patients preferences regarding future investigation and treatment guide the clinical decision. This article focuses on primary and secondary prevention, and discusses specific criteria to consider in each patient. A table summarizes the appropriate recommendations.