865 resultados para empirical data


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This article focuses on challenges of transnational aging and family care among „guest-workers‟ from Italy and Spain. It is based on two qualitative studies on aging in migration and experiences of family care. These migrants‟ situations tend to be socioeconomically underprivileged, yet they have the option to either stay in Switzerland or return to Italy or Spain. Our results show that an additional option is available by combining elements of both national systems of reference. However, these options are often costly and have short-comings which are particularly relevant when ill health conditions demand intensified care. By then, decisions taken within the context of transnational ways of living have far-reaching consequences that affect not only the elderly migrants but also their adult children. The empirical data presented in this article illustrate how specific constellations of caring options emerge from the Swiss „guest-worker‟ migration regime and from transnational practices and choices made in earlier years.

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Identifying drivers of species diversity is a major challenge in understanding and predicting the dynamics of species-rich semi-natural grasslands. In particular in temperate grasslands changes in land use and its consequences, i.e. increasing fragmentation, the on-going loss of habitat and the declining importance of regional processes such as seed dispersal by livestock, are considered key drivers of the diversity loss witnessed within the last decades. It is a largely unresolved question to what degree current temperate grassland communities already reflect a decline of regional processes such as longer distance seed dispersal. Answering this question is challenging since it requires both a mechanistic approach to community dynamics and a sufficient data basis that allows identifying general patterns. Here, we present results of a local individual- and trait-based community model that was initialized with plant functional types (PFTs) derived from an extensive empirical data set of species-rich grasslands within the `Biodiversity Exploratories' in Germany. Driving model processes included above- and belowground competition, dynamic resource allocation to shoots and roots, clonal growth, grazing, and local seed dispersal. To test for the impact of regional processes we also simulated seed input from a regional species pool. Model output, with and without regional seed input, was compared with empirical community response patterns along a grazing gradient. Simulated response patterns of changes in PFT richness, Shannon diversity, and biomass production matched observed grazing response patterns surprisingly well if only local processes were considered. Already low levels of additional regional seed input led to stronger deviations from empirical community pattern. While these findings cannot rule out that regional processes other than those considered in the modeling study potentially play a role in shaping the local grassland communities, our comparison indicates that European grasslands are largely isolated, i.e. local mechanisms explain observed community patterns to a large extent.

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Empirical data suggest that the race of calving of grounded glaciers terminating in water is directly proportional to the water depth. Important controls on calving may be the extent to which a calving face tends to become oversteepened by differential flow within the ice and the extent to which bending moments promote extrusion and bottom crevassing at the base of a calving face. Numerical modelling suggests that the tendency to become oversteepened increases roughly linearly with water depth. In addition, extending longitudinal deviatoric stresses at the base of a calving face increase with water depth. These processes provide a possible physical explanation for the observed calving-rate/water-depth relation.

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The present study investigated the relationship between psychometric intelligence and temporal resolution power (TRP) as simultaneously assessed by auditory and visual psychophysical timing tasks. In addition, three different theoretical models of the functional relationship between TRP and psychometric intelligence as assessed by means of the Adaptive Matrices Test (AMT) were developed. To test the validity of these models, structural equation modeling was applied. Empirical data supported a hierarchical model that assumed auditory and visual modality-specific temporal processing at a first level and amodal temporal processing at a second level. This second-order latent variable was substantially correlated with psychometric intelligence. Therefore, the relationship between psychometric intelligence and psychophysical timing performance can be explained best by a hierarchical model of temporal information processing.

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RATIONALE In biomedical journals authors sometimes use the standard error of the mean (SEM) for data description, which has been called inappropriate or incorrect. OBJECTIVE To assess the frequency of incorrect use of SEM in articles in three selected cardiovascular journals. METHODS AND RESULTS All original journal articles published in 2012 in Cardiovascular Research, Circulation: Heart Failure and Circulation Research were assessed by two assessors for inappropriate use of SEM when providing descriptive information of empirical data. We also assessed whether the authors state in the methods section that the SEM will be used for data description. Of 441 articles included in this survey, 64% (282 articles) contained at least one instance of incorrect use of the SEM, with two journals having a prevalence above 70% and "Circulation: Heart Failure" having the lowest value (27%). In 81% of articles with incorrect use of SEM, the authors had explicitly stated that they use the SEM for data description and in 89% SEM bars were also used instead of 95% confidence intervals. Basic science studies had a 7.4-fold higher level of inappropriate SEM use (74%) than clinical studies (10%). LIMITATIONS The selection of the three cardiovascular journals was based on a subjective initial impression of observing inappropriate SEM use. The observed results are not representative for all cardiovascular journals. CONCLUSION In three selected cardiovascular journals we found a high level of inappropriate SEM use and explicit methods statements to use it for data description, especially in basic science studies. To improve on this situation, these and other journals should provide clear instructions to authors on how to report descriptive information of empirical data.

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Studies of food webs suggest that limited nonrandom dispersal can play an important role in structuring food webs. It is not clear, however, whether density-dependent dispersal fits empirical patterns of food webs better than density-independent dispersal. Here, we study a spatially distributed food web, using a series of population-dispersal models that contrast density-independent and density-dependent dispersal in landscapes where sampled sites are either homogeneously or heterogeneously distributed. These models are fitted to empirical data, allowing us to infer mechanisms that are consistent with the data. Our results show that models with density-dependent dispersal fit the α, β, and γ tritrophic richness observed in empirical data best. Our results also show that density-dependent dispersal leads to a critical distance threshold beyond which site similarity (i.e., β tritrophic richness) starts to decrease much faster. Such a threshold can also be detected in the empirical data. In contrast, models with density-independent dispersal do not predict such a threshold. Moreover, preferential dispersal from more centrally located sites to peripheral sites does not provide a better fit to empirical data when compared with symmetric dispersal between sites. Our results suggest that nonrandom dispersal in heterogeneous landscapes is an important driver that shapes local and regional richness (i.e., α and γ tritrophic richness, respectively) as well as the distance-decay relationship (i.e., β tritrophic richness) in food webs.

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BACKGROUND Pathogenic bacteria are often asymptomatically carried in the nasopharynx. Bacterial carriage can be reduced by vaccination and has been used as an alternative endpoint to clinical disease in randomised controlled trials (RCTs). Vaccine efficacy (VE) is usually calculated as 1 minus a measure of effect. Estimates of vaccine efficacy from cross-sectional carriage data collected in RCTs are usually based on prevalence odds ratios (PORs) and prevalence ratios (PRs), but it is unclear when these should be measured. METHODS We developed dynamic compartmental transmission models simulating RCTs of a vaccine against a carried pathogen to investigate how VE can best be estimated from cross-sectional carriage data, at which time carriage should optimally be assessed, and to which factors this timing is most sensitive. In the models, vaccine could change carriage acquisition and clearance rates (leaky vaccine); values for these effects were explicitly defined (facq, 1/fdur). POR and PR were calculated from model outputs. Models differed in infection source: other participants or external sources unaffected by the trial. Simulations using multiple vaccine doses were compared to empirical data. RESULTS The combined VE against acquisition and duration calculated using POR (VEˆacq.dur, (1-POR)×100) best estimates the true VE (VEacq.dur, (1-facq×fdur)×100) for leaky vaccines in most scenarios. The mean duration of carriage was the most important factor determining the time until VEˆacq.dur first approximates VEacq.dur: if the mean duration of carriage is 1-1.5 months, up to 4 months are needed; if the mean duration is 2-3 months, up to 8 months are needed. Minor differences were seen between models with different infection sources. In RCTs with shorter intervals between vaccine doses it takes longer after the last dose until VEˆacq.dur approximates VEacq.dur. CONCLUSION The timing of sample collection should be considered when interpreting vaccine efficacy against bacterial carriage measured in RCTs.

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The most influential theoretical account in time psychophysics assumes the existence of a unitary internal clock based on neural counting. The distinct timing hypothesis, on the other hand, suggests an automatic timing mechanism for processing of durations in the sub-second range and a cognitively controlled timing mechanism for processing of durations in the range of seconds. Although several psychophysical approaches can be applied for identifying the internal structure of interval timing in the second and sub-second range, the existing data provide a puzzling picture of rather inconsistent results. In the present chapter, we introduce confirmatory factor analysis (CFA) to further elucidate the internal structure of interval timing performance in the sub-second and second range. More specifically, we investigated whether CFA would rather support the notion of a unitary timing mechanism or of distinct timing mechanisms underlying interval timing in the sub-second and second range, respectively. The assumption of two distinct timing mechanisms which are completely independent of each other was not supported by our data. The model assuming a unitary timing mechanism underlying interval timing in both the sub-second and second range fitted the empirical data much better. Eventually, we also tested a third model assuming two distinct, but functionally related mechanisms. The correlation between the two latent variables representing the hypothesized timing mechanisms was rather high and comparison of fit indices indicated that the assumption of two associated timing mechanisms described the observed data better than only one latent variable. Models are discussed in the light of the existing psychophysical and neurophysiological data.

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Research on open source software (OSS) projects often focuses on the SourceForge collaboration platform. We argue that a GNU/Linwr distribution, such as Debian, is better suited for the sampling ofprojects because it avoids biases and contains unique information only available in an integrated environment. Especially research on the reuse of components can build on dependency information inherent in the Debian GNU/Linux packaging system. This paper therefore contributes to the practice of sampling methods in OSS research and provides empirical data on reuse dependencies in Debian.

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This article presents an approach for segmenting sporting event volunteers according to differences in their motives. Empirical data were obtained from a sample of 1169 volunteers who registered for the 2014 European Athletics Championships in Zürich. They completed the ‘Volunteer Motivation Scale for International Sporting Events’ (VMS-ISE) questionaire. The validity of the VMS-ISE was replicated by confirmatory factor analysis and the data were cluster analysed to identify distinct motivation-based volunteer profiles. These segmented volunteers on the basis of mutually exclusive motivational characteristics. The external validity of the four motivation-based types (‘community supporters’, ‘material incentive seekers’, ‘social networkers’ and ‘career and personal growth orienteers’) was confirmed with socio-economic, sport-related and volunteer activity-related variables. It is concluded that motivation-based segmentation represents a useful way of gaining a clearer understanding of the patterns underlying the heterogeneity of sporting events volunteers.

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​This book presents an up-to-date portrait of the characteristics of sport clubs in various European countries and their role in society and the national sport system. Furthermore, it offers a cross-national comparative perspective of sport clubs in twenty European countries. Containing both empirical data and information on the political and historical backgrounds of sport clubs, the book is organized in three parts. First, the authors provide an overview of the theoretical approach of the book and a description of the framework used for the country chapters. Second, the country chapters, written by experts within the field, provide a systematic overview of the available information on sport clubs in each country. These chapters are structured to answer the following questions: (1) What is the position of sport clubs within the national sport structure? (2) Which role do they fulfil in policy and society? (3) What are their basic characteristics and what factors influence the development of sport clubs? The book is concluded with a systematic comparison of the participating countries with the purpose of forging a clear link between the functioning of policy systems, observed problems, and possible solutions, and with a future research agenda on sport clubs. In an era of increased collaboration between European states, sport provides a natural vehicle through which to compare changes in culture, economics, and policy across nations. Sport Clubs in Europe will appeal to scholars of nonprofit management, sports management and sports sociology as well as administrators and policy makers in the international sports community.

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After the collapse of the Soviet Union and Yugoslavia, a number of actors started to engage in the power struggle for the opportunities to shape the new order in successive nation-states. In Serbia and Georgia historically hegemonic Orthodox Christian churches were among the firsts in the frontlines for political and economic power. More than a decade has passed since the so-called Coloured Revolutions in Georgia and Serbia, and the Orthodox churches still remain participants of an ongoing socio-political transition of these states. The revival of public role of religion appeared temporary in Serbia followed by a gradual decline of an influence of the Orthodox Church over political life and legal process. However, in Georgia the public and political role of religion increased rather than declined albeit changed shape. Examining the degree to which the two Orthodox churches can influence the political agenda in Serbia and Georgia, the paper attempts to understand how church-State relations work in practice. By bringing rich empirical data from the field (70 interviews with (arch)bishops, priests and religious clerics in Georgia and Serbia added to field observations), the paper reflects on the themes under which the two Orthodox churches mobilize public protest in Serbia and Georgia. The paper further looks at varying State responses and their broader implication for church-state problematique.

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Introduction: According to the ecological view, coordination establishes byvirtueof social context. Affordances thought of as situational opportunities to interact are assumed to represent the guiding principles underlying decisions involved in interpersonal coordination. It’s generally agreed that affordances are not an objective part of the (social) environment but that they depend on the constructive perception of involved subjects. Theory and empirical data hold that cognitive operations enabling domain-specific efficacy beliefs are involved in the perception of affordances. The aim of the present study was to test the effects of these cognitive concepts in the subjective construction of local affordances and their influence on decision making in football. Methods: 71 football players (M = 24.3 years, SD = 3.3, 21 % women) from different divisions participated in the study. Participants were presented scenarios of offensive game situations. They were asked to take the perspective of the person on the ball and to indicate where they would pass the ball from within each situation. The participants stated their decisions in two conditions with different game score (1:0 vs. 0:1). The playing fields of all scenarios were then divided into ten zones. For each zone, participants were asked to rate their confidence in being able to pass the ball there (self-efficacy), the likelihood of the group staying in ball possession if the ball were passed into the zone (group-efficacy I), the likelihood of the ball being covered safely by a team member (pass control / group-efficacy II), and whether a pass would establish a better initial position to attack the opponents’ goal (offensive convenience). Answers were reported on visual analog scales ranging from 1 to 10. Data were analyzed specifying general linear models for binomially distributed data (Mplus). Maximum likelihood with non-normality robust standard errors was chosen to estimate parameters. Results: Analyses showed that zone- and domain-specific efficacy beliefs significantly affected passing decisions. Because of collinearity with self-efficacy and group-efficacy I, group-efficacy II was excluded from the models to ease interpretation of the results. Generally, zones with high values in the subjective ratings had a higher probability to be chosen as passing destination (βself-efficacy = 0.133, p < .001, OR = 1.142; βgroup-efficacy I = 0.128, p < .001, OR = 1.137; βoffensive convenience = 0.057, p < .01, OR = 1.059). There were, however, characteristic differences in the two score conditions. While group-efficacy I was the only significant predictor in condition 1 (βgroup-efficacy I = 0.379, p < .001), only self-efficacy and offensive convenience contributed to passing decisions in condition 2 (βself-efficacy = 0.135, p < .01; βoffensive convenience = 0.120, p < .001). Discussion: The results indicate that subjectively distinct attributes projected to playfield zones affect passing decisions. The study proposes a probabilistic alternative to Lewin’s (1951) hodological and deterministic field theory and enables insight into how dimensions of the psychological landscape afford passing behavior. Being part of a team, this psychological landscape is not only constituted by probabilities that refer to the potential and consequences of individual behavior, but also to that of the group system of which individuals are part of. Hence, in regulating action decisions in group settings, informers are extended to aspects referring to the group-level. References: Lewin, K. (1951). In D. Cartwright (Ed.), Field theory in social sciences: Selected theoretical papers by Kurt Lewin. New York: Harper & Brothers.

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The purpose of this dissertation was to survey men in the Harris County Jail (HCJ) to establish a more valid estimate of childhood sexual abuse (CSA) prevalence in a jailed-based population; to assess whether inmates with a history of CSA were at greater risk for use of drugs and alcohol and engaging in high-risk sexual behaviors than those without histories of childhood sexual abuse. ^ The first study determined the prevalence of childhood sexual abuse among incarcerated males in a county jail. In this study, sixty-three percent of the subjects reported having been sexually abused. Sixty-one percent reported abuse pre-puberty and 10% reported abuse post puberty. In pre-puberty abuse the initiation of first abuse occurred at a mean age of 5.6 years (SD 5.096, range: 2–13 years). ^ The second study explored the association between inmates with histories of CSA as a risk factor for sexual risk behaviors. A history of sexual abuse did not appear to be associated with an elevated risk of sexual risk behaviors. ^ The third study explored a history of drug use and a history of CSA among the inmates. A chi-square test showed that the inmates who reported a history of CSA, was significantly greater for the following drugs: Marijuana (02), Crack (03), Heroin/Morphine (.03), Amphetamines/Speed (01), Downers/Barbiturates (.001), Methamphetamine/Crystal Meth (.001), Valium .02), LSD/Acid (.001), and Inhalants (.001), p < .05). Significance was not found in alcohol, tobacco, cocaine, Quaaludes and methadone. ^ The research from this study provides empirical data supporting previous research. The current data shows that incarcerated inmates have a high prevalence of childhood sexual abuse and drug use. Sexual victimization as a child does not appear to be associated with an elevated risk of unsafe sexual behaviors. However, men who used drugs were twice as likely to have engaged in unprotected sex with casual and regular partners, and rarely used condoms with paid sex. Although our study methods do not permit a causal explanation for this association, we believe it is of concern. Finally, data in this study shows that sexually abused children are likely candidates for adult criminal behavior. ^

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This thesis seeks to analyze the relationship between public attitudes toward refugees in a refugee receiving state and the realization of the legal rights afforded refugees (de facto rights). I hypothesize that the more negative a host culture is toward refugees, the less refugees are able to realize their rights. Conversely, the more positive a host culture is toward refugees, the more refugees are able to realize their rights. I test the hypothesis through a case study of refugee populations in Cape Town, South Africa, based on research conducted from May to June 2007. The orientation (positive or negative) of the host culture's perceptions toward a refugee group (Independent Variable) is measured through: (1) a coded content analysis of the South African media, (2) a coded content analysis of semi-structured interviews, and (3) an assessment of secondary source public opinion surveys and reports. The realization of refugee rights (Dependent Variable) is operationalized as a function of two rights: (1) the right to personal physical integrity and (2) the right to protection from unlawful detention. These rights are measured by coding (1) media reports and (2) interviews, and by (3) assessing NGO reports and secondary source public opinion surveys. My empirical data shows that the cultural orientation toward refugees is not overwhelmingly negative, and the realization of rights is not conclusively "low." However, the frequency of data coded "negative" and "low" versus "positive" or "high" suggest that South Africans regard refugees somewhat negatively and that rights are not fully realized. This finding is strengthened by the analysis of secondary sources and field notes.