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1.
Spatial variation in soil inorganic nitrogen across an arid urban ecosystem   总被引:4,自引:1,他引:3  
We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well as for the desert and urban sites separately. Concentrations of both NO3-N and NH4-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO3-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious surfaces and lawn, whereas soil NH4-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO3-N and NH4-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation of soil NO3-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than factors related to an urban-rural gradient.  相似文献   
2.
This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.  相似文献   
3.
Sex differences in expressiveness are well documented, but the reasons for and correlates of these important differences are not well studied. A comprehensive set of emotion-relevant personality measures was administered to 40 female and 39 male undergraduate participants, who were also videotaped in three situations: engaging in natural social interaction, describing a past emotional experience, and posing various emotions. Videotapes were judged by sets of naive observers as to emotion communicated and overall impression. Expressive females, who appeared friendly and dominant in social interaction, were found to have a hostile/aggressive personality (but this was not true of males). Expressive females also tended to look angry/disgusted when describing happy and sad experiences. The findings suggest that nonverbally skilled, charismatic women (but not men) may often possess a dominant/aggressive but self-controlled personality, in a new twist on the theory that sex differences in expressiveness result in part from the oppression of women in society.This research was supported in part by an intramural research grant from University of California, Riverside.  相似文献   
4.
The paper describes the group therapy model which has evolved over the past two years on the Child Psychiatry Inpatient Unit of North Carolina Memorial Hospital. It begins with a brief review of the literature concerning group therapy with latency-aged children. The setting and patient population are described. Vignettes from group sessions are used to illustrate techniques which have evolved to deal with this particular setting and population. These include a leadership style characterized by much clarification, modeling, and limit setting; extensive focus on beginning and terminating; clearly defined behavioral limits; the use of time out; and use of play materials requiring little skill or attention as anxiety binders as well as projective media; and observation and supervisory discussions open to all members of the treatment team. The paper concludes with a discussion of the potentials and limitations of group therapy in such a setting. The thesis is that this model is effective in diagnosing developmental levels, in developing interpersonal skills, in substituting verbalization for action, and in mastering separation anxieties, though the setting limits the extent to which controlled regression, transference, and group pressures can develop and be used to produce change.  相似文献   
5.
This study investigates the validity of the assumption that coordination and citizen participation are related inversely and, thus, are incompatible as features in the same social service reform strategy. Seventeen social service organizations situated in the same urban area were studied. Data were obtained by structured interview. The concepts of coordination and citizen participation were operationalized by means of scales. The findings support the validity of the assumption noted above. Although interpretations of the findings can be provided, they are post-factum. This implies a need for explanatory research which might be guided by theories of community power structure and of organizational behavior.  相似文献   
6.
As the financial crisis of 2008 demonstrates, wide discretion is provided by accounting rules for determining the reporting entity, especially with respect to special purpose entities (SPEs). In this paper, it is shown that the newly issued regulations of International Financial Reporting Standards (IFRS) 10 may not entirely solve the off-balance-sheet problem. As a result, consolidated financial statements may not provide useful information on the financial situation of the reporting entity with respect to the conceptual framework of IFRS. This paper presents an alternative concept in the light of neoinstitutional theories for determining the reporting entity with respect to proactive subsidiaries as well as to SPEs with and without autopilots. Specifically, the economic activities of the reporting entity are characterized based on property rights theory in a first step. Second, for SPEs, this paper tests whether these economic activities should be integrated into the efficient boundaries of the reporting entity based on transaction cost theory. The concept developed is evaluated by (1) analyzing it against the background of the conceptual framework of IFRS and the Exposure Draft ED/2010/2 “Conceptual Framework for Financial Reporting—The Reporting Entity”, (2) applying it to typical structures within the reporting entity, and (3) comparing its effectiveness to the effectiveness of the rules of IFRS 10.  相似文献   
7.
Grandparents’ regular care for children while parents work has been mostly studied from the parental perspective. This paper focuses on the grandparents. Using the Australian Bureau of Statistics Time Use Survey 2006 (N = 7672) we investigate regular-caring grandparents’ demographic characteristics, which childcare activities they undertake, and how regular childcare provision relates to their time in other activities, subjective time pressure and satisfaction. Results indicate the correlates and nature of regular care differ by gender. Regular and non-regular-caring grandmothers’ relative time allocation to different childcare tasks barely differs, while regular-caring grandfathers’ care includes a much higher proportion of active care and travel than non-regular-caring grandfathers’. Regular care provision is associated with less leisure than non-regular-caring counterparts for both genders, but with only grandmothers’ housework, personal care and sleep time. Providing regular care doubles the likelihood of grandmothers reporting high subjective time pressure compared to non-regular-caring grandmothers; there is no association between regular care and time pressure for grandfathers. We conclude that in taking on regular care, grandparents echo the gender patterns found among parents, namely that it is women who are disproportionately impacted by meeting family care needs.  相似文献   
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Differences in patient characteristics, including age, sex, and race influence the safety and effectiveness of drugs, biologic products, and medical devices. Here we provide a summary of the topics discussed during the opening panel at the 2018 Johns Hopkins Center for Excellence in Regulatory Science and Innovation symposium on Assessing and Communicating Heterogeneity of Treatment Effects for Patient Subpopulations: Challenges and Opportunities. The goal of this session was to provide a brief overview of FDA-regulated therapeutics, including drugs, biologics and medical devices, and some of the major sources of heterogeneity of treatment effects (HTE) related to patient demographics, such as age, sex and race. The panel discussed the US Food and Drug Administration's role in reviewing and regulating drugs, devices, and biologic products and the challenges associated with ensuring that diverse patient populations benefit from these therapeutics. Ultimately, ensuring diverse demographic inclusion in clinical trials, and designing basic and clinical research studies to account for the intended patient population's age, sex, race, and genetic factors among other characteristics, will lead to better, safer therapies for diverse patient populations.  相似文献   
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