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71.
We report on what, to our knowledge, represents the first study of nonverbal emotional behavior in crowded public places combining naturalistic videotaping of situated activity, objective coding of facial movement, and sequential analysis of behavior. In the first part of the study we argue that passengers do not lose emotional sensitivity to physical contact as density (passengers per square meter) increases, which indicates that physical contact is experienced as a territorial intrusion regardless of crowdedness. In the second part of the study, we suggest that passengers resolve the emotions due to intrusive physical contacts through two interactional strategies involving facial movements usually interpreted as “expressions of emotions.” Since proxemic violations seem to represent a pervasive emotion elicitor, the protocol can be extended to other means of transportation and replicated in other locations. We conclude that the methodology provides an effective tool for theory-building in the study of nonverbal emotional behavior.  相似文献   
72.
Urban growth is a major factor of global environmental change and has important impacts on biodiversity, such as changes in species composition and biotic homogenization. Most previous studies have focused on effects of urban area as a general measure of urbanization, and on few or single taxa. Here, we analyzed the impacts of the different components of urban sprawl (i.e., scattered and widespread urban growth) on species richness of a variety of taxonomic groups covering mosses, vascular plants, gastropods, butterflies, and birds at the habitat and landscape scales. Besides urban area, we considered the average age, imperviousness, and dispersion degree of urban area, along with human population density, to disentangle the effects of the different components of urban sprawl on biodiversity. The study was carried out in the Swiss Plateau that has undergone substantial urban sprawl in recent decades.Vascular plants and birds showed the strongest responses to urban sprawl, especially at the landscape scale, with non-native and ruderal plants proliferating and common generalist birds increasing at the expense of specialist birds as urban sprawl grew. Overall, urban area had the greatest contribution on such impacts, but additional effects of urban dispersion (i.e., increase of non-native plants) and human population density (i.e., increases of ruderal plants and common generalist birds) were found. Our findings support the hypothesis that negative impacts of urban sprawl on biodiversity can be reduced by compacting urban growth while still avoiding the formation of very densely populated areas.  相似文献   
73.
BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable.  相似文献   
74.
A field experiment on the discrimination of Roma migrants from Eastern Europe was conducted in two stations of the Paris metro to explore the behaviors that may communicate misrecognition in everyday encounters. An actress asked for help to randomly chosen passengers on a metro platform, wearing a glaringly Romani skirt in the treatment condition but an unconspicuous middle-class style in the control condition. In interaction with the actress wearing the Romani skirt, passengers were found to enact the so-called “visual dominance pattern”, and male passengers in particular were found to keep greater distances. Reverse discrimination also occurred as women kept shorter distances from the actress bearing the ethnic stigma. Last, passengers helped less the stigmatized actress, but only in one of the two metro stations where trials were conducted.  相似文献   
75.
This article reports on the outcome of a Future Search Conference in the UK to consider human resource development (HRD) in 2020 and beyond. We firstly consider themes from the past into the present. This includes the persistence of solutions in HRD that are systematic, predictable, how apprenticeships in the UK have had to accommodate government policies to ameliorate youth unemployment and the long-standing difficulty for HRD of failing to demonstrate a return on investment (ROI) on activities. We then present four scenarios based on key questions for the future relating to value of HRD and whether this will be a future for HRD. Reponses to the questions form scenario logics which we present against the theme of city tour. Each scenario is explained against the presented logic with positive, negative, ambiguous and uncertain implications for HRD. We suggest that each scenario carries a glimpse of what might be.  相似文献   
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78.
This article measures the degree to which academic economists have engaged in unethical behavior and the degree to which academic economists believe the profession as a whole engages in unethical behavior. Three main types of unethical behavior are examined: (1) falsification of research; (2) expropriation of graduate student research or including an undeserving co-author on a research paper; and (3) exchange of grades for gifts, money, or sex. Using a unique data set gathered at the 1998 American Economic Association (AEA) meetings, we find that there is a significant amount of misconduct, particularly in the second category.  相似文献   
79.
Pseudo‐values have proven very useful in censored data analysis in complex settings such as multi‐state models. It was originally suggested by Andersen et al., Biometrika, 90, 2003, 335 who also suggested to estimate standard errors using classical generalized estimating equation results. These results were studied more formally in Graw et al., Lifetime Data Anal., 15, 2009, 241 that derived some key results based on a second‐order von Mises expansion. However, results concerning large sample properties of estimates based on regression models for pseudo‐values still seem unclear. In this paper, we study these large sample properties in the simple setting of survival probabilities and show that the estimating function can be written as a U‐statistic of second order giving rise to an additional term that does not vanish asymptotically. We further show that previously advocated standard error estimates will typically be too large, although in many practical applications the difference will be of minor importance. We show how to estimate correctly the variability of the estimator. This is further studied in some simulation studies.  相似文献   
80.
The nonparametric two-sample bootstrap is applied to computing uncertainties of measures in receiver operating characteristic (ROC) analysis on large datasets in areas such as biometrics, speaker recognition, etc. when the analytical method cannot be used. Its validation was studied by computing the standard errors of the area under ROC curve using the well-established analytical Mann–Whitney statistic method and also using the bootstrap. The analytical result is unique. The bootstrap results are expressed as a probability distribution due to its stochastic nature. The comparisons were carried out using relative errors and hypothesis testing. These match very well. This validation provides a sound foundation for such computations.  相似文献   
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