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941.
The distribution of ant colonies within a community is often well defined, yet this distribution can change due to changing environmental conditions, resource availability, and colony growth. In this study, structure infesting ant communities were sampled for one year within three Puerto Rican housing developments of different ages. These developments represented environments in different stages of recovery after a disturbance (secondary succession). Spatial mapping was used to plot the distribution and abundance of ant communities within these developments. At the beginning of the study, the youngest housing development (1 year since construction), had the fewest number of species present (ave. 1.6 per house). The second housing development (4 years old) had a greater number of species (ave. 2.6 per house), and a greater sampling frequency (the same species collected at multiple houses) than Site 1. The oldest development (8 years old) had both the greatest number of species (ave. 2.7 per house), and sampling frequency of the three sites. In all developments, the number of species, sampling frequency, and ant biomass increased throughout the year as colonies grew and foraging ranges expanded. It was observed in all developments, that species coexistence also increased throughout the year. As colony populations increased, there was a greater occurrence of multiple species being collected at the same sample house. In the youngest development, the two most dominant species increased in numbers during the year and began to be collected from the same sample houses. Spatial diagrams documented that multiple species in the older housing developments (later stages of succession), also shared a common distribution. Even the most dominant species (S. invicta) in all three sites, did not exclude additional species from foraging within its established range.  相似文献   
942.
943.
Two synchronous projects undertaken in 2011 examined the likely impact of increasing urban densification on invertebrate populations within urban settlement in Perth, Western Australia. One project analysed the ant fauna found in 20 gardens and lawns in small to very small properties (these having a bungalow or duplex (semi-detached) as the main residential building, and a lawn or garden area of 43 m2–332 m2) east, south, north and west of the Central Business District (CBD). The other project examined the ant fauna at 14 sites, principally in native regrowth along the Kwinana Freeway, a major artery that runs north to south through Perth’s suburbs. The gardens and lawns produced a very depauperate fauna of 26 ant species, of which a maximum of 20 were native and at least six species were exotic. The ant fauna from regrowth adjacent to the Kwinana Freeway and at two additional sites (one a bush control) was more than twice as rich, the 56 species collected including only two exotics. In the garden project, ant richness, evenness and abundance were not significantly correlated with size of the garden area. The same applied even when the exotic Pheidole megacephala-dominated gardens were removed from the analysis. Ordination analysis combining the two sets of data revealed a distinct clustering of most of the regrowth sites, whereas the bush control stood alone and garden or lawn sites exhibited a much looser pattern of association. We suggest that increasing the density of Perth suburbs is resulting in drastic loss of native invertebrate fauna, of which ants are a useful bioindicator. However, native vegetation regrowth along major arterial roads could act as a reservoir for invertebrate species that might otherwise disappear entirely from the Perth metropolitan area.  相似文献   
944.
Susan Migden Socolow, The Bureaucrats of Buenos Aires, 1769–1810: Amor al Real Servicio (1987), xxi + 356 (Duke University Press, Durham, N.C., $45.00).

W. Hamish Fraser, Conflict and Class. Scottish Workers 1700–1838 (1988), 202 (John Donald, £20.00).

Margaret Ripley Wolfe, Kingsport, Tennessee: A Planned American City (1987), xii + 259 (The University Press of Kentucky, Lexington, £24.00).

Carl Chinn, They Worked All Their Lives. Women of the Urban Poor in England, 1880–1939 (1988), xii + 187 (Manchester University Press, Manchester, £22.50).

Linda Bryder, Below the Magic Mountain: A Social History of Tuberculosis in Twentieth‐Century Britain (1988), xv + 298 (Oxford University Press, Oxford, £30.00).

F. B. Smith, The Retreat of Tuberculosis 1850–1950 (1988), 271 (Croom Helm, £25.00).  相似文献   
945.
Research on casual sexual relationships (CSRs) among emerging adults is prevalent, yet our empirical and theoretical knowledge of relationship processes involved in these relationships is limited. The present study’s objective was to compare four CSR partner types (acquaintance, friend, non-dating partner, ex-romantic partner) on passion, intimacy, and commitment, the components of Sternberg’s triangular theory of love. A total of 441 Canadians aged 18–25 years who were not in a romantic relationship, and who reported having had more than one sexual contact with their last CSR partner, completed an online survey. Across all partner types, passion was highest, followed by intimacy and commitment. Levels of passion, intimacy, and commitment generally increased with partner familiarity. However, CSR partner type differences on the three components were partially explained by CSR components (i.e., frequency of sexual activity, frequency of social activity, whether partners saw each other with the main goal of having sex, sexual exclusivity agreement, and hopes about the relationship). Results are consistent with CSRs’ emphasis on sexuality, and, to a lesser extent, emotions. However, they challenge the mainstream and scientific conflation of CSRs with an absence of emotional bond, commitment, or love.  相似文献   
946.
Social work students need to develop practice skills with racially and ethnically diverse clients. Previous research has found benefits to using individual simulated clients, and working with a group would not only provide facilitation opportunities, it could also increase students’ exposure to diversity. This article presents a social work group practice class that used simulated clients and the evaluation of the pedagogy using a mixed-methods design. Students’ scores on the Diversity and Oppression Scale significantly improved from pretest to posttest. Focus groups clarified the impact. The results of this exploratory pilot study suggest that this approach allowed students to learn to manage emotional responses, promoted student insights, and provided opportunities to challenge student assumptions.  相似文献   
947.
This is an evaluative study on the delivery of devolved programs in health, agriculture and social welfare. It aimed to identify the major devolved programs/projects implemented by the LGU of Columbio, Sultan Kudarat; the responsiveness of the actual delivery of devolve services in terms of human resources, facilities and fund allocation; the status of devolve services implemented if it was effective and efficient; and the inadequacies encountered. The “expose facto” method of research was used. There were 49 implementers and 132 beneficiaries of the various devolved programs. There were 181 total respondents. A four-part questionnaire was constructed and the gathered data were supplemented by information extracted through interviews with Key Informants, Focus Group Discussions and document analysis. There were three departments implementing the devolved social services programs such as the Municipal Health Office with 6 devolved health programs; the Municipal Agriculturist Office with 6 devolved agricultural projects; and the Municipal Social Welfare and Development Office with 7 devolved social welfare programs. The respondents rated the implementation of devolve services in health, agriculture and social welfare programs between rank 5 to 9 for the aspects of human resources, facilities and fund allocations. The respondents assessed the implementation of devolved programs as Very Efficient and Most Responsive programs to the needs of the people specially the children, youths and women. The study also found some inadequacies observed during the implementation of devolved social services programs which were Agreed by the majority of the respondents. These findings implied that the implementation of various devolved social services for several years has made a significant difference in the lives of the people of the Municipality of Columbio, Sultan Kudarat, the Local Government of Columbio and program implementers with their commitment and solidarity to serve the people especially the marginalized is a manifestation of their unselfish dedication to uplift the socio-economic condition and well-being of the people. Hence, continuing projects should further be strengthened and supported to ensure the sustainability of the projects even if the support of different institutions has been terminated.  相似文献   
948.
The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web‐based surveys describing sibling conflict and warmth. Siblings reported on trustworthiness and modeling, and mothers described adjustment. Sibling conflict was directly associated with internalizing and externalizing behaviors for both siblings. The older siblings' reports of trustworthiness were directly associated with the outcome measures. The younger siblings' reports of trustworthiness were less directly associated, but a possible salutary effect was most evident under the highest levels of sibling conflict or warmth. Higher sibling modeling was a risk factor for adjustment problems in relations characterized by high conflict. Results support exploring trustworthiness as a key dimension of sibling relations.  相似文献   
949.
Bistrategic resource control entails using both coercive and prosocial strategies in competition for resources. The present study sought to clarify whether bistrategic involves more than simply using both strategies some of the time. Examining 88 preschoolers' coercion and prosociality over an entire school year, results showed that coercive resource control was used most frequently at the start of the school year, presumably to access resources and establish social dominance. Rates of prosocial resource control increased over the school year, and socially dominant preschoolers showed higher rates compared with peers, presumably to maintain resource control while keeping peers as allies. Socially dominant preschoolers also used reconciliation more often than peers, resulting in higher rates of affiliation between former competitors and more positive peer regard from fall to spring. Findings are discussed in terms of resource control theory and the importance of situating social behaviors within the behavioral and relationship context in which they are embedded.  相似文献   
950.
We introduce a general Monte Carlo method based on Nested Sampling (NS), for sampling complex probability distributions and estimating the normalising constant. The method uses one or more particles, which explore a mixture of nested probability distributions, each successive distribution occupying ∼e −1 times the enclosed prior mass of the previous distribution. While NS technically requires independent generation of particles, Markov Chain Monte Carlo (MCMC) exploration fits naturally into this technique. We illustrate the new method on a test problem and find that it can achieve four times the accuracy of classic MCMC-based Nested Sampling, for the same computational effort; equivalent to a factor of 16 speedup. An additional benefit is that more samples and a more accurate evidence value can be obtained simply by continuing the run for longer, as in standard MCMC.  相似文献   
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