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971.
We examined whether relatively small urban ponds behave as ‘completely mixed reactors’ by measuring the stability and vertical heterogeneity of water column parameters. To do this, we measured profiles of water temperature and conductivity from the pond surface to the water-sediment interface twice during summer 2009 in 45 stormwater ponds located in the residential landscape of southern Ontario. These data were used to calculate water column stability indices and examine the relative importance of temperature and conductivity in controlling water column stratification. We also measured concentrations of dissolved oxygen (DO), dissolved organic carbon (DOC), total dissolved phosphorus (TDP),total dissolved nitrogen (TDN), particulate phosphorus and nitrogen (seston P and N), chlorophyll a (Chl-a), and total suspended solids (TSS) in surface and bottom waters. Despite their shallow depth (0.50–2.8 m), most ponds were stratified on the day of sampling and had relatively stable water columns both in June and August. Temperature differences rather than conductivity differences were better related to water column stability. Despite relatively stable water columns, vertical differences were not found for most water chemistry parameters, suggesting either recent mixing or relatively slow biogeochemical processing. Top-bottom differences were observed in June and August for DO and in June for TDN, seston N and TSS, reflecting a combination of processes influencing water column chemistry.  相似文献   
972.
Rhetorical questions emerging spontaneously in consultations can be used as a tool for developing self‐reflexivity and exploring the therapeutic alliance in the process of therapy with couples and families. This paper presents a technique based on the enunciation of rhetorical questions, which can point to an impasse in the process of therapy and contain a key to its resolution. The technique focuses on the distinctive feature of rhetorical questions as convening a paradoxical injunction: a question not intended as a question, while uttered as such. The technique in four steps is illustrated by examples from therapy, supervision, consultation, and self‐supervision. Its focus is the interlink between the therapeutic relationship and the process of therapy and it is informed by a second‐order cybernetics approach, dialogical practice, and the systemic literature on emotion. The technique can help develop curiosity in working with families, lead to unforeseen developments, and touch on prejudices not made explicit in previous therapeutic encounters. Whether we are acting as supervisors, therapists, or clients, the creation of a ‘secure enough’ context for rhetorical questions becomes critical to allow freeform exploration.  相似文献   
973.
该文在 1 997年的中国投入产出表的基础上作适当修改 ,编制出信息产业投入产出表 ,据此建立模型并计算出带动度和带动度系数。通过对信息产业进行研究 ,该文认为信息产业已成为国民经济的第二主导产业 ,对国民经济其他各部门总产品变动的影响很大 ,而且还有着很大的发展空间  相似文献   
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This article proposes and evaluates a method to test for mediation in multilevel data sets formed when an intervention administered to intact groups is designed to produce change in individual mediator and outcome variables. Simulated data of this form were used to compare ordinary least squares (OLS) and two multilevel estimators of the mediated effect. OLS and multilevel standard error approximations were also evaluated and recommendations given for optimal estimator choice. These methods were applied to data from an existing substance use intervention to show the impact multilevel mediation modeling can have on the conclusions drawn from real-world evaluation studies.  相似文献   
978.
This is a case study of gender and earnings in pharmacy--a profession characterized by its rapid recruitment of female practitioners. We try to account for disparities in earnings between male and female pharmacists in Ontario with the aid of human capital theory and gender stratification theory. Data is drawn from a random sample of 463 Ontario pharmacists. We find a consistent sex gap in earnings regardless of occupational level of practitioners (i.e. owner, manager or employee) and net of such factors as hours worked, commitment to work, hours devoted to childcare, absences from the labour market, and years since graduation. Instead, the main reason why women in pharmacy earn less than males is because they remain employees throughout their careers. However, we are less successful at identifying the additional factors responsible for the depressed earnings of female practitioners. We discuss our findings in light of the claims of gender stratification and human capital theory.  相似文献   
979.
This article discusses the role of politics in the Juvenile Justice Educational Enhancement Program's effort to use evaluation research data to inform Florida's juvenile justice education policies and practices. Through consideration of the Juvenile Justice Education Enhancement Program's experiences with privatization and the tough love and economy of scale rationales for larger and more custodial juvenile institutions, the variable role of politics is examined. Although the two examples are different, the discussion demonstrates that by maintaining an overriding commitment to its evaluation research purpose, the Juvenile Justice Educational Enhancement Program has been able to continue its data-driven policy efforts despite operating in a politically charged environment.  相似文献   
980.
To examine correlates of the speed at which female soldiers carrying loads could cover 3.2 km on foot and traverse an obstacle course, 12 volunteers (mean +/- SD: 25.3 +/- 6 years, 166 +/- 7 cm, 61.3 +/- 7 kg) were timed over 3.2 km while carrying loads of 14, 27, and 41 kg, and while traversing an obstacle course with the two lighter loads. Pearson correlations showed that absolute VO_[2 max] and 3.2 km run time without a load were the best predictors of 3.2 km load carriage time for all loads. Also, larger subjects with greater muscle mass were able to carry the heaviest load faster than smaller, less muscular subjects, likely because the 41 kg load represented a smaller percentage of the former's bodyweight. Maximum number of sit-ups and push-ups, composite score of the Army Physical Fitness Test as well as body height were positively correlated with the speed at which some course segments were traversed.  相似文献   
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