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491.
Since the Last Planner System® (LPS) was devised in the early 90s, a number of studies have pointed out the need to understand the underlying theory in which it is based on. The Language-Action Perspective (LAP) has been suggested as a suitable approach to understand the management of commitments in the LPS. This paper aims to assess the contribution of LAP to understand construction planning and control systems based on LPS. Two case studies were carried out in different construction companies, both highly experienced on the use of LPS. The results reveal the role of LAP for creating explicit representations of commitment flows that can be used to explain the sources of complexity and failures in planning systems, as well as for describing the profile of planning and control meetings.  相似文献   
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493.
This teaching note examines the use of intentional, identity-centered spaces in the social work classroom. We discuss the use of identity-based caucusing as a means of centering the embodied and lived experiences of students in the social work classroom, drawing from previous classroom experiences in an MSW foundation course on social justice at a large public university. Specifically, we consider borderland perspectives and postcolonial constructions of third spaces and their usefulness in social work pedagogy. In particular, we pose questions regarding the use of third space caucusing as a means of embracing and affirming both/and, neither/nor identity positionalities. We also consider possibilities of student-centered, critical pedagogical approaches while paying attention to the unique challenges and contexts of social work education.  相似文献   
494.
Pettinga  D.  Kennedy  J.  Proppe  D. S. 《Urban Ecosystems》2016,19(1):373-382

Recent studies suggest that songbird communication is negatively affected by anthropogenic noise. However, much of the current literature focuses on inter- and intra-sexual communication. Songbirds also use acoustic cues for many other functional behaviors. One example associated with fitness consequences is the identification of predatory threats through acoustic cues. To test the effect of anthropogenic noise on detection of acoustic cues, we compared the rates of seven anti-predator behavioral responses in urban dwelling songbirds foraging at bird feeders when exposed to playback of calls from predatory Cooper’s hawks under quiet conditions, and when overlapped with road noise. Only a single behavior, freeze response, decreased significantly when calls were overlapped with noise. However, freeze responses occurred in only a small percentage of playback trials, raising some question regarding the biological relevance of this observed difference. Overall, our results suggest that common urban songbirds are relatively successful at perceiving acoustic signals associated with predator presence. Whether this ability is commonplace amongst songbird species is unknown and warrants additional study. However, if this trait is not widespread, it may be an additional characteristic determining which bird species can inhabit noisy areas.

  相似文献   
495.
Urban Ecosystems - Many street trees in urban areas are deciduous and drop leaves during autumn. These leaves are a potential growing substrate for fungi, which when aerosolized and inhaled, can...  相似文献   
496.
497.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals.  相似文献   
498.
We used a longitudinal community study of 674 grade school children (Grades 5, 6, 7, and 8; 337 males, 337 females) of Mexican origin to examine outcomes of school attachment. Attachment to school is important in this population given the high level of school dropout rates of Mexican‐origin students. Results indicated that, on average, school attachment from fifth to sixth grade remains stable, but declines from sixth to eighth grade. Boys had lower levels of school attachment at fifth grade but followed similar patterns of change as girls did. Attachment to teachers, peer competence, school aspirations and expectations, and substance‐use cognitions emerged as longitudinal outcomes of level or changes in school attachment. Gender moderated associations of school attachment.  相似文献   
499.
Association of demanding kin relations and family routine with adolescents' psychological distress and school achievement was assessed among 200 low‐income, African American mothers and adolescents. Demanding kin relations were significantly associated with adolescents' psychological distress. Family routine was significantly related to adolescents' school achievement. Demanding kin relations were negatively associated with school achievement for adolescents from families low in routine, but unrelated to achievement for adolescents in families high in routine. Additional research is needed on poor families and their social networks.  相似文献   
500.
Emotional relationships in infant–mother dyads in families where mothers provided full‐time childcare were compared with those of families where mothers used in‐home childcare providers and family childcare providers (= 245). Infant relationships with childcare providers were also studied. Emotional relationships were adequate in all three childcare arrangements, but infant–mother dyads in in‐home childcare arrangements displayed healthier emotional relationships than infant–mother dyads in mother care arrangements; no differences in the health of emotional relationships with infants emerged among the three types of childcare providers (mother care, in‐home childcare, family childcare). Infant–mother dyads in in‐home childcare arrangements also displayed healthier emotional relationships than infant–in‐home childcare caregiver dyads, but infant–mother and infant–caregiver dyads were comparable in family childcare families. Emotional relationships in infant–mother and infant–caregiver dyads were not correlated, regardless of the type of childcare.  相似文献   
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