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11.
Rényi divergences are used to propose some statistics for testing general hypotheses in mixed linear regression models. The asymptotic distribution of these tests statistics, of the Kullback–Leibler and of the likelihood ratio statistics are provided, assuming that the sample size and the number of levels of the random factors tend to infinity. A simulation study is carried out to analyze and compare the behavior of the proposed tests when the sample size and number of levels are small.  相似文献   
12.
We describe a one-dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg-containing foods. Six categories of egg-containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home-made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home-made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft-boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science-based approach to inform consumer risk communications regarding safe egg handling practices.  相似文献   
13.
Social welfare systems face major challenges, particularly in a context of social transformation, austerity and growing inequalities. This process is highly visible in the health sector. In this context, many voices ask for public sector reforms and community action for health as a relevant practice. However, analyses and evaluations of this kind of practices are still limited, particularly beyond the cases of single community health actions or interventions. We still need to identify key indicators for measuring and characterising what community action for health consists of, as well as to what degree this kind of intervention has been developed across a city. Based on a research about 49 neighborhoods in Barcelona, this paper creates an index to measure and characterize community action for health, using different indicators: citizen engagement programs in community health, organizational transformation of the health and social protection systems, stable participatory structures with specific teams, and urban health policies. We apply the index to the case of Barcelona and build a map of community action for health in the city using 4 categories: strong community health development (one neighbourhood), middle (9 neighborhoods), emergent (25 neighborhoods) and without specific community health promotion (14 neighbourhoods). We find that community action for health is extensive within the city of Barcelona, have great potential as a response to the need for change in the relationship between the public (health) sector and the citizenry, but is still implemented unequally across the urban territory in terms of types and methods.  相似文献   
14.
In spring 2006, the United States witnessed immigrant marches throughout the nation. Although Latina/os are often depicted as the “face” of the immigrant marches, we know little about how racial and citizenship statuses shaped Latina/os’ perceptions of how the marches influenced public perceptions of undocumented immigrants. Using logistic regression on data from the 2006 National Survey of Latinos, we find that Latina/os identifying as white are less likely to be supportive of the immigrant marches than those who defied standard racial classifications, and instead identified as “Latina/o.” Moreover, Latina/os who are born in the United States are not as supportive of the immigrant marches in comparison with naturalized citizens and non‐citizen Latina/os, accounting for demographic and human capital factors. This study suggests there is a “racial‐ and citizenship divide” among Latina/os that fragments perceptions on the immigrant mobilizations in the United States.  相似文献   
15.
We exploit Bayesian criteria for designing M/M/c//rM/M/c//r queueing systems with spares. For illustration of our approach we use a real problem from aeronautic maintenance, where the numbers of repair crews and spare planes must be sufficiently large to meet the necessary operational capacity. Bayesian guarantees for this to happen can be given using predictive or posterior distributions.  相似文献   
16.
17.
A good parametric spectral estimator requires an accurate estimate of the sum of AR coefficients, however a criterion which minimizes the innovation variance not necessarily yields the best spectral estimate. This paper develops an alternative information criterion considering the bias in the sum of the parameters for the autoregressive estimator of the spectral density at frequency zero.  相似文献   
18.
In this paper we formulate the problem of constructing 1-rotational near resolvable difference families as a combinatorial optimization problem where a global optimum corresponds to a desired difference family. Then, we develop an algorithm based on scatter search in conjunction with a tabu search to construct many of these difference families. In particular, we construct three new near resolvable difference families which lead to an equal number of new 1-rotational near resolvable block designs with parameters: (46,9,8), (51,10,9) and (55,9,8). Our results indicate that this conjunction outperforms both scatter search and tabu search.  相似文献   
19.
Purpose. To determine the value of available questionnaires used for the diagnosis of testosterone deficiency syndromes (TDS) by correlating their ratings with a panel of hormonal determinations in a male population.

Materials and methods. Participants completed the ADAM questionnaire and underwent biochemical evaluation at the local site. Assessments determined entry into Group A (symptomatic) or Group B (non-symptomatic). After stratification, subjects provided a morning sample of blood, completed the Aging Male Survey (AMS) and the newly developed Canadian Society for the Study of the Aging Male (CSAM-Q) questionnaires. Serum aliquots were analysed at a central lab for 8 putative markers commonly associated with symptomatic testosterone deficiency associated with aging: total testosterone (T); bioavailable T (BT); dehydroepiandrosterone sulphate (DHEA-S); sex-hormone binding globulin (SHBG); luteinizing hormone (LH), prolactin (PRL); thyroid-stimulating hormone (TSH) and insulin-like growth factor-1 (IGF-1).

Results. 92 men were screened; of these 59 (mean age of 58 ± 11 years) completed the study, 30 (51%) scored positively (mean 61.5 years) to the ADAM while 29 (49%) did not (mean 54.1 years). For the AMS the weight of the three domains (psychological, somato-vegetative and sexual) was significantly greater in Group A (p < 0.001) than in Group B. Equally, for the CAS questionnaire, the scores for the variables energy, global performance, frequency of intercourse, mood and quality of sleep were lower in Group A than in their asymptomatic counterparts (p < 0.001). The domain of memory assessment within the CSSAM-Q was not discriminatory. ADAM and AMS are self-administered and completed within 10 minutes. CSSAM-Q is more time consuming, requires an investigator to administer, and memory domain is biased in favour of specific professional training.

No difference was found between the two groups in 6 of 8 biochemical tests. However, significant lower values (p < 0.001) were found for DHEA-S and IGF-1 in the symptomatic group as compared with the non-symptomatic cohort.

Conclusions. This study confirms that newer, more complex tools perform similarly to the simpler ADAM questionnaire. The lack of correlation between the clinical picture and the most commonly used biochemical confirmatory tests, again, clearly points to the paramount importance of the clinical evaluation. An emphasis and reliance on serum T alone hinders the clinician's ability to manage testosterone deficiency syndromes (TDS).  相似文献   
20.
Introduccion     
Resumen

El miedo, como una de las consecuencias de la situación sociopolítica de Argentina en los últimos años, ha afectado, y sigue afectando, a la mayor parte de los miembros de esa sociedad, presentando características diferentes según el periodo considerado, es decir, dictadura, transición a la democracia o gobierno democrático concreto. Se discuten sus implicaciones para la sociedad y se sugieren algunas formas de afrontarlo.  相似文献   
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