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41.
Alterations in stream environments can alter fish food availability, but there is little research data related to the impacts of urbanization on fish diets in tropical streams. Thus, we sought to compare the diet of ten fish species in urbanized and non-urbanized streams reaches. Fish stomach contents were obtained for four urban and five non-urban stream reaches from two medium-sized cities. We verified the similarity of diet composition from urbanized/non-urbanized streams. In-stream features mainly related to the substrate highlighted a perturbation gradient: gravel, pebbles and cobbles were associated to the wider urban reaches while silt were representative in the narrow pools from non-urban streams. Fishes changed their diet in response to urban and non-urban treatments. Omnivorous fishes consumed more detritus and Chironomidae and less terrestrial adult insects in urban reaches, while invertivorous fish consumed more terrestrial adult insects and Trichoptera larvae in the non-urbanized stream reaches. Although the management of the physical structure of streams in Brazil has been basically focused on riparian reforestation, our results suggest that a restoration plan for urban streams cannot be limited to reforestation of its surroundings, but also need to consider the physical structure of the channel, especially the substrate, which contributes to promote in-stream variability.  相似文献   
42.
The Ergonomic Work Analysis reports that there are many activities performed by the professional caregivers and that they are exposed to physical and psychological overload. This situation favors the emergence of pain which influences the quality of life in the work place. In this way, the objective of this study was to verify the main postural constraints adopted by caregivers in public day cares. Visits were conducted in 28 day cares aiming at performing an interview to 126 caregivers who have been working for more than 4 years. From the questionnaire it was found that 80% of the participants refer some sort of pain, being 42% in the trunk, 33% in the shoulder and 25% in the lower limbs. The data from OWAS method showed that from the total of 30 postures performed during the work One could see that the main postures adopted by the caregivers were: flexion, lateral inclination and rotation of the trunk and most of the time they are standing. These movements, when bad performed, can lead to injuries in the lower limbs, upper limbs and trunk. It's necessary more attention to these workers.Thought preventive ergonomic actions to reduce pain symptoms and promote a work in health and safety.  相似文献   
43.
This study examined whether teachers’ perceptions of students’ behavior (referring to halo effects) and the behavior of teacher‐perceived friends (referring to association effects) influenced teachers’ ability to recognize students identified as bullies, victims, and prosocial by their peers. Data came from 1,458 children (Mage = 10.5, 47.5% girls) and 56 teachers (Mage = 40.8, 66.1% females). Perceived likeability was associated with decreased odds and teachers’ perceptions of popularity and externalizing behavior were associated with increased odds for teacher attunement to bullying. Perceived likeability and affiliation were associated with decreased odds for teacher attunement to victimized students. Teachers’ perceptions of externalizing behavior were associated with decreased odds, whereas teachers’ perceptions of affiliation and academic competence were associated with increased odds for attunement to prosociality. Finally, a positive association was found between teacher attunement and the average behavior of teacher‐perceived friends for bullying, victimization, and prosociality.  相似文献   
44.
Visual attention patterns measured with eye-tracking techniques provide indirect clues about sexual response. This study aimed to test the category specificity of sexual responses to stimuli varying in gender and age by evaluating both early and late attention of gynephilic and androphilic men and women. We simultaneously presented sexually preferred and nonpreferred stimuli and measured time to first fixation and total duration of fixation on four areas of interest: entire body, then face, chest, and pelvis. Androphilic women’s early attention patterns were nonspecific, whereas gynephilic women and both groups of men showed a category-specific pattern for the entire body. In contrast, all groups showed gender-specific patterns of late attention for all areas of interest. We also found support for age specificity of early and late visual attention in all four groups, with greater attention to adult than child stimuli. This study supports the usefulness of a competing stimulus eye-tracking paradigm as a method to examine gender specificity in gynephilic women and androphilic and gynephilic men, and as a measure of age specificity in gynephilic and androphilic men and women.  相似文献   
45.

By doing a parallel between old and new reforms on governance issues applied in Latin America, this paper seeks to identify learnings as well as to understand what is new and what is not from this type of policy endeavor. The article focuses on the analysis of the State reforms implemented in Latin America during the 1920s and those of the 1990s. It shows that modernization of public administration follows the State reform; that needs calling for modernization are permanent; and that while ends pursued by the State change in the long run, modernization has to be a permanent activity.

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46.
A fundamental characteristic of any innovation is its novelty, the newness or freshness of the innovation in the eyes of the adopter. Past research has often considered novelty to be inherent to an information technology (IT) innovation, yet it is also likely that perceptions of novelty differ widely across individuals. Nevertheless, the role that the novelty of an IT innovation plays in adoption is not well understood. The primary goal of this research effort is to frame the perceived novelty of an IT innovation as a salient affective belief in the nomological network related to adoption. Further, we examine how perceived novelty influences the way individuals reconcile their perceptions of risk versus reward when considering the adoption of an IT innovation. Two empirical studies with 424 and 138 participants, respectively, examine the effect of perceived novelty on IT innovations from a risk/reward perspective. Results indicate that perceived novelty is a salient affective belief that plays a significant role in the adoption of IT innovations. Implications for both theory and organizational decision making are examined.  相似文献   
47.
48.
The main aim of this article is to investigate the behavioral consequences of the provision of subject-specific information in the group effort levels chosen by players in an experimental CPR game. We examine two basic treatments, one with incomplete information and the other with complete information. In the former, subjects are informed only about their own individual payoffs and the aggregate extraction effort level of the group, and in the latter they are also informed about the individual effort levels and payoffs of each subject. Given this setting, the basic question we attempt to answer is: Will the provision of subject-specific performance information (i.e. individual’s effort levels and payoffs) improve or worsen the tragedy of the commons (i.e. an exploitation effort level greater than the socially optimum level)? In order to motivate our hypotheses and explain our experimental results at the individual level, we make use of the theory of learning in games, which goes beyond standard non-cooperative game theory, allowing us to explore the three basic benchmarks in the commons context: Nash equilibrium, Pareto efficient, and open access outcomes. We use several learning and imitation theoretical models that are based on contrasting assumptions about the level of rationality and the information available to subjects, namely: best response, imitate the average, mix of best response and imitate the average, imitate the best and follow the exemplary learning rules. Finally, in order to econometrically test the hypotheses formulated from the theoretical predictions we use a random-effects model to assess the explanatory power of the different selected behavioral learning and imitation rules.  相似文献   
49.
This article presents a dynamic game theoretic model of voting in the presence of asymmetric information about a relevant parameter of the economy, the state of the world. Voters may use both vote splitting and reelection as mechanisms of electoral control. In a perfect Bayesian equilibrium, voters will reelect an Executive incumbent if a minimum level of social outcome, n *, is attained. The main findings are that voters tend to be more demanding, requiring a higher value for n *, if they expect the true state of the world to be favorable, and less demanding if they believe the state of the world is unfavorable. Moreover, vote splitting will be chosen if a favorable state is expected, whereas if an unfavorable state is more likely, voters reduce pressure over the incumbent by choosing a unified government. Received: 9 October 2000/Accepted: 11 February 2002 The author is grateful to Mirta Bugarin, Brian Gaines, Wilfredo Maldonado, Otto Reich, Brian Sala, Marilda Sotomayor, Steven Williams, the participants of the Third Lacea Meeting, the Summer Seminars of the Political Science Department, University of Illinois, the Seminar Program of the Department of Economics of the University of Brasilia and the First World Congress of the Game Theory Society for valuable discussions on previous versions of this article. None of the above is responsible for errors or opinions expressed. The financial support from CNPq/Brazil is gratefully acknowledged.  相似文献   
50.
In this paper, we provide probabilistic predictions for soccer games of the 2010 FIFA World Cup modelling the number of goals scored in a game by each team. We use a Poisson distribution for the number of goals for each team in a game, where the scoring rate is considered unknown. We use a Gamma distribution for the scoring rate and the Gamma parameters are chosen using historical data and difference among teams defined by a strength factor for each team. The strength factor is a measure of discrimination among the national teams obtained from their memberships to fuzzy clusters. The clusters are obtained with the use of the Fuzzy C-means algorithm applied to a vector of variables, most of them available on the official FIFA website. Static and dynamic models were used to predict the World Cup outcomes and the performance of our predictions was evaluated using two comparison methods.  相似文献   
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