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451.
The purpose was to analyze the influence of winning the first ball possession on the partial and final score in male and female water polo. The 288 matches disputed by the teams participating in the 2003, 2005, and 2007 Water Polo World Championship were recorded. The results reflect statistically significant differences for the influence of gaining the first ball possession on the partial and final scoreboard of each period and for the influence between the total number of first possessions obtained and the final result.  相似文献   
452.
We introduce the Profinite Hull functor of special groups, showing that it gives rise to a new (and strong) local-global principle, the subform reflection property. We also indicate applications of this principle to the abstract algebraic theory of quadratic forms.  相似文献   
453.
Recent work on comorbidity finds evidence for hierarchical structure of mood and anxiety disorders and symptoms. This study tests whether a higher-order internalizing factor accounts for variation in depression and anxiety symptom severity and change over time in a sample experiencing a period of major life stress. Data on symptoms of depression, chronic worry, and social anxiety were collected five times across seven months from 426 individuals who had recently lost jobs. Growth models for each type of symptom found significant variation in individual trajectories. Slopes were highly correlated across symptom type, as were intercepts. Multilevel confirmatory factor analyses found evidence for a higher-order internalizing factor for both slopes and intercepts, reflective of comorbidity of depression and anxiety, with the internalizing factor accounting for 54% to 91% of the variance in slopes and intercepts of specific symptom sets, providing evidence for both a general common factor and domain-specific factors characterizing level and change in symptoms. Loadings on the higher order factors differed modestly for men and women, and when comparing African American and White participants, but did not differ by age, education, or history of depression. More distal factors including gender and history of depression were strongly associated with internalizing in the early weeks after job loss, but rates of change in internalizing were associated most strongly with reemployment. Findings suggest that stressors may contribute in different ways to the common internalizing factor as compared to variance in anxiety and depression that is independent of that factor.  相似文献   
454.
The study of intimate partner violence among adolescent and young couples in Spain remains unattended, although such abuses are well known and more frequent than in adulthood. The aim of this study is, on the one hand, to provide epidemiological information on dating relationships, and on the other hand, to identify attitudes towards violence. 2205 women enrolled in schools in diverse provinces of Spain, participated in the study. Average age was near 19 years (SD= 2.25). The Dating Violence Questionnaire (DVQ, in Spanish, CUVINO), a questionnaire that assesses both frequency and distress associated with violent behavior, was used. The DVQ allowed differentiating between groups of women self-labeled as abused and not abused on the basis of the frequency of sustained violence, although the levels of distress in the face of violence were statistically similar in both groups. Implications for future research and prevention programs are discussed.  相似文献   
455.
The aim of this study was to analyze the exploratory and confirmatory structure, as well as other psychometric properties, of the Cuestionario de Problemas de Convivencia Escolar (CPCE; in Spanish, the Questionnaire on School Maladjustment Problems [QSMP]), using a sample of Spanish adolescents. The instrument was administered to 60 secondary education teachers (53.4% females and 46.6% males) between the ages of 28 and 54 years (M= 41.2, SD= 11.5), who evaluated a total of 857 adolescent students. The first-order exploratory factor analysis identified 7 factors, explaining a total variance of 62%. A second-order factor analysis yielded three dimensions that explain 84% of the variance. A confirmatory factor analysis was subsequently performed in order to reduce the number of factors obtained in the exploratory analysis as well as the number of items. Lastly, we present the results of reliability, internal consistency, and validity indices. These results and their implications for future research and for the practice of educational guidance and intervention are discussed in the conclusions.  相似文献   
456.
This paper describes a useful technique for quantifying the degree of speech deficits in dementia of GDS 4 Alzheimer's type (DAT). Production of prosodic speech in DAT patients and healthy older controls was analysed using variation in fundamental frequency (F0) measures on a reading task. The prosogram computational model was used to analyze the prosodic contours of the speech samples, using melodic styling of F0 based on perceptual principles and prominence detection of spectral and amplitude fluctuations in the speech signal. Results revealed significant differences in most of these prosodic parameters among the DAT group. Normal pitch variation in speech and variations in syllable timing were reduced in the DAT group, these features cause "flat" speech prosody in these patients. These speech parameters may have diagnostic and prognostic value for Alzheimer's disease and therefore could be a useful aid in clinical trials.  相似文献   
457.
This paper describes several simulation studies that examine the effects of capitalization on chance in the selection of items and the ability estimation in CAT, employing the 3-parameter logistic model. In order to generate different estimation errors for the item parameters, the calibration sample size was manipulated (N = 500, 1000 and 2000 subjects) as was the ratio of item bank size to test length (banks of 197 and 788 items, test lengths of 20 and 40 items), both in a CAT and in a random test. Results show that capitalization on chance is particularly serious in CAT, as revealed by the large positive bias found in the small sample calibration conditions. For broad ranges of theta, the overestimation of the precision (asymptotic Se) reaches levels of 40%, something that does not occur with the RMSE (theta). The problem is greater as the item bank size to test length ratio increases. Potential solutions were tested in a second study, where two exposure control methods were incorporated into the item selection algorithm. Some alternative solutions are discussed.  相似文献   
458.
Relapses in cocaine abusers in treatment are an important problem. The majority of patients are incapable of sustaining abstinence over any length of time. To identify the factors associated to relapses risk in the cocaine use can be an optimal choice to improve the treatment strategies. The aim of this study was to analyze relapse-risk factors in cocaine-dependent patients on treatment. Participants were 102 patients who had begun outpatient treatment at a public health center in Spain. Some functional areas and cocaine use are evaluated for a period of six months. A structural equations model was used to identify possible predictive variables. The results show that social-family environment and economic-employment situation were associated with greater risk of relapse. Likewise, the social-family environment was related to severity of addiction. It is concluded that the incorporation of family intervention strategies and vocational/employment counseling may help to reduce relapse rates in cocaine addicts receiving treatment.  相似文献   
459.
The twenty-first century presents a major challenge for civil engineering. The magnitude and future importance of some of the problems perceived by society are directly related to the field of the civil engineer, implying an inescapable burden of responsibility for a group whose technical soundness, rational approach and efficiency is highly valued and respected by the citizen. However, the substantial changes in society and in the way it perceives the problems that it considers important call for a thorough review of our structures, both professional and educational; so that our profession, with its undeniable historical prestige, may modernize certain approaches and attitudes in order to continue to be a reliable instrument in the service of society, giving priority from an ethical standpoint to its actions in pursuit of ??the public good??. It possesses important tools to facilitate this work (new technologies, the development of communications, the transmission of scientific thought.···); but there is nevertheless a need for deep reflection on the very essence of civil engineering: what we want it to be in the future, and the ability and willingness to take the lead at a time when society needs disinterested messages, technically supported, reasonably presented and dispassionately transmitted.  相似文献   
460.
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