The effect of urban ground covers on arthropods: An experiment

Changes to the ground layer in urban areas are extensive, but the effects on arthropod fauna are poorly understood. We undertook a manipulative experiment to examine the response of arthropods to small-scale variation in ground covers commonly found in urban parks and gardens in Australia. The ground covers tested were bare ground, leaf litter, woodchips and grass, with plot sizes of 3.6 m². Epigeic arthropods were sampled with pitfall traps and Tullgren funnels over 12 months following establishment of the treatments. All epigeic arthropods were sorted to order and the ants (Hymenoptera: Formicidae), beetles (Coleoptera), millipedes (Diplopoda) and slaters (Isopoda: Oniscidea) were examined at lower taxonomic levels. Diverse arthropods rapidly colonised previously cleared plots in all four treatments and were most abundant in grass plots. The diversity of ants and beetles was significantly different in different ground covers and tended to be most diverse in grass plots. Despite the treatments providing very different microclimates, the fauna studied did not show strong selection for a particular cover type overall. The abundance of grass cover in the surrounding area may have led to the grass plots having the greatest abundance of arthropods. These results have important implications for developing effective small-scale conservation efforts for arthropods in anthropogenically modified landscapes, especially for species with poor dispersal abilities.     

Into the Wilderness—A Case Study: The Psychodynamics of Adolescent Depression and the Need for a Holistic Intervention

Adolescent depression has become epidemic in the United States, with statistics showing that one in five adolescents may suffer from depression (Brent and Birmaher in N Engl J Med 347(9), 2002). This article examines adolescent depression from a psychodynamic perspective, and identifies the psychodynamics of adolescent depression as the affective correlates that stem from unresolved developmental conflicts, issues of separation/individuation, the search for identity and the development of the true self. This article presents wilderness therapy as a holistic intervention which can be used to address the intrapsychic, developmental and relational factors that give rise to adolescent depression. Wilderness therapy is a modality of mental health treatment that takes place outdoors and utilizes challenge and adventure, group work and other structured clinical interventions. A clinical case study presents wilderness therapy as an effective intervention for adolescent depression that can promote positive self-image and enhanced coping skills, and discusses limitations and implications for social work practice.     

执行战略的最佳管理实践

引进新的部门,全力打造战略中心型组织的最佳实践 是什么使平衡计分卡的成功使用者 与众不同?这是人们经常问我们 的问题。平衡计分卡的成功是艺 术还是科学?是运气,抑或仅仅因为平衡 计分卡的使用者如此众多,必定会有一些 成功者?过去的一年里,我们一直致力于     

REGULATION, THE OPEC OIL SUPPLY SHOCK, AND WEALTH EFFECTS FOR ELECTRIC UTILITIES

A popular view among specialists in electric utility economics is that the regulatory process exacerbated the negative effects of the OPEC's oil price increases during the 1970s. In contrast, Peltzman's theory of regulation suggests that regulators should "buffer" a firm from cost increases. This paper examines these contending propositions by examining the stock returns for a sample of electric utilities during the OPEC oil shock of October 1973. The data are more consistent with a buffering effect than a regulatory lag.     

Economic evaluation of an agricultural sector investment program: A case study for Peru

An evaluation of a sector-wide investment program differs in important respects from an evaluation of an individual project. First, the program as a whole is likely to have more than a marginal effect on production and trade levels and other variables, and so the returns to any one project depend on which other projects are included in the program. Therefore the evaluation of all projects in the program must be carried out jointly. Second in many cases Policy makers may judge alternative program designs according to a multiplicity of criteria, explicitly or implicity. Hence the project identification stage of work is more useful if it takes into account the multiple criteria. This paper reports an experience in constructing and applying a model for the design and evaluation of a sector-wide agricultural investment program. Emphasis is placed on the ways in which such a model may be used. In the course of the applications discussed here, policy makers' preference weights among alternative goals were elicited, but even without such information a model-based exercise can be helpful in the design of a sector investment program.     

A civic trend within ethnic transnationalism? Some insights from classical social theory and the Chinese American experience

Abstract In this article I contribute to the debates on transnationalism by reconceptualizing the relationship between transnationalism and assimilation. I posit an ideal‐type distinction between gemeinschaft‐ and gesellschaft‐like transnational practices and suggest an evolving trend towards the latter. In so doing, I show how two bodies of existing work that have generally been self‐contained can usefully be integrated in the study of transnationalism–namely the work of Glick Schiller, Portes and others on ethnic transnationalism and that of Keohane, Sikkink and others on civic transnationalism. In the article I treat the experience of Chinese Americans, who are a pertinent case for analysis because of their longstanding migration to and presence in US society. I begin by laying a theoretical foundation, go on to trace the history of Chinese American transnationalism, present evidence of contemporary Chinese Americans' involvement in a variety of civic associations, and conclude with discussion of this visible trend towards heightened civic transnational activity.     

Lability of prenatal stress during the COVID-19 pandemic links to negative affect in infancy

The association between prenatal stress and children's socioemotional development is well established. The COVID-19 pandemic has been a particularly stressful period, which may impact the gestational environment. However, most studies to-date have examined prenatal stress at a single time point, potentially masking the natural variation in stress that occurs over time, especially during a time as uncertain as the pandemic. This study leveraged dense ecological momentary assessments from a prenatal randomized control trial to examine patterns of prenatal stress over a 14-week period (up to four assessments/day) in a U.S. sample of 72 mothers and infants. We first examined whether varied features of stress exposure (lability, mean, and baseline stress) differed depending on whether mothers reported on their stress before or during the pandemic. We next examined which features of stress were associated with 3-month-old infants' negative affect. We did not find differences in stress patterns before and during the pandemic. However, greater stress lability, accounting for baseline and mean stress, was associated with higher infant negative affect. These findings suggest that pathways from prenatal stress exposure to infant socioemotional development are complex, and close attention to stress patterns over time will be important for explicating these pathways.     

Equal division of estates and the exchange motive

Although the bequest motive is one of the most important theoretical extensions of the life-cycle hypothesis, few empirical studies have measured determinants of unequal estate division. We estimated whether several proxies that are consistent with exchange and altruism lead to unequal estate division using data from a longitudinal survey of deceased elderly persons linked to probate court records. Equal division was the rule-between 70 and 83% of estates were divided equally, depending on the strictness of the definition of equal division. Several measures of exchange were not significant predictors of unequal division. Two factors that are consistent with both exchange and altruism- writing the last will and testament within five years of death and having more children-predict unequal estate division. The models control for selection, because many decedents do not file a record in probate court.