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971.
Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines, lacks a theoretical framework that synthesizes the diverse and important aspects of heterogeneity. This paper presents the concept of dynamic heterogeneity as a tool to explore how social and ecological heterogeneities interact and how they together act as both an outcome of past interactions and a driver future heterogeneity and system functions. To accomplish this goal, we relate heterogeneity to the fundamental concept of the human ecosystem. The human ecosystem concept identifies key processes that require operationalized models of dynamic heterogeneity in three process realms: the flow of materials, the assembly of urban ecosystem biota, and the locational choices humans make concerning land. We exemplify a specific dynamic model of heterogeneity in each of these realms, and indicate a range of complementary statistical approaches to integrate the drivers and outcomes of dynamic heterogeneity across the three realms. We synthesize a hierarchical framework for a theory of dynamic urban heterogeneity, noting its complementarity to other major urban theories and general model approaches. We hypothesize that human actions and structures amplify the dynamics of heterogeneity in urban systems.  相似文献   
972.
In sprawling metropolitan areas, residential landscaping is a major concern with respect to biodiversity conservation, and it could play a critical role in conserving wildlife habitat. In the United States, residential landscaping typically consists of maintained lawns with specimen plantings of non-native trees and shrubs; such designs provide poor habitat for urban wildlife species. We conducted a case study of Raleigh, North Carolina residents to determine how providing information about the benefits of native plant landscaping to bird species influenced urban residents’ landscaping preferences. We used Wilcoxon Signed Rank tests to determine if respondent preferences for 0, 50, 75 and 100 % native plant landscaping coverages changed after residents were informed about the benefits that native plants provide for birds. Initially, the 50 % native landscaping coverage was most preferred by residents; however, preferences for all four native plant landscaping coverage designs were significantly different after the informational treatment. Neutrality changed to opposition for the 0 % native plant coverage, while opposition changed to support and neutrality for the 75 and 100 % native plant coverage designs, respectively. After the informational treatment, the 50 and 75 % native plant landscaping coverage had the highest mean preference levels, although the 100 % design was ranked first more than any other design. Our findings suggest that residential support for native plant landscaping is higher than is reflected by typical residential landscaping practices, and that dissemination of information regarding the benefits of native plant landscaping to birds could alter public preferences for native plant landscaping.  相似文献   
973.
ABSTRACT

The aging of the United States population is creating an increased need for social workers and other helping professionals with training in gerontology. Recent estimates indicate that less than 3% of MSW students are enrolled in an aging concentration, as compared to 19% enrolled in children/youth concentrations. In addition, the phenomenon of a diverse baby boomer generation joining the ranks of persons age 65 and older has created a plethora of scholarship and curriculum development aimed at readying the aging network for the unprecedented growth of older persons. Social work can make unique professional contributions to the field of gerontology and older persons. This study asserts, however, that social work is not adequately prepared to practice in an increasingly diverse aging society. The social work profession has articulated commitments to acknowledging and affirming how diversity and culture shape the human experience and to developing social workers who can competently engage in research-informed practice and practice-informed research. However, there remains a need in social work education for more widespread use of culturally relevant pedagogies that can help achieve these goals. Informed by both the Afrocentric and Black perspectives, this study presents a content analysis of the curricula infused at two historically Black universities. The nature and extent of the contributions of historically Black universities to social work education is the focus of this article. The scope of this investigation also includes the identification of prominent Black social work educators and discusses the implications of these perspectives for more culturally informed gerontology curricula that promote culturally competent gerontological social workers.  相似文献   
974.
The role of urban expansion on bee diversity is poorly understood, but it may play an important role in restructuring pollinator diversity observed in rural regions at the urban perimeter. We studied bee communities in two habitats essential for pollinators (residential gardens and semi-natural areas) at 42 sites situated at the edge of greater Montreal, Canada. Bee species richness, abundance and functional diversity all increased with urbanization in both habitat types, but gardens and semi-natural areas supported distinct bee communities with unique responses to urbanization in terms of species turnover. Compared to semi-natural sites, residential gardens supported bees that foraged from a greater number but a lower proportion of available plant species. Bees did not discriminate between exotic and indigenous plant species in either gardens or semi-natural sites and were attracted to flowers in either habitat irrespective of their origins. Protecting semi-natural ruderal areas and providing residential garden habitats for pollinators are both effective means of promoting regional bee diversity in urbanizing regions.  相似文献   
975.
976.
Erectile dysfunction (ED) is one of the most common disorders in male and is often associated with other age-related comorbidities. The aging process affects the structural organization and function of penile erectile components such as smooth muscle cell and vascular architecture. These modifications affect penile hemodynamics by impairing cavernosal smooth muscle cell relaxation, reducing penile elasticity, compliance and promoting fibrosis. This review aims to identify the mechanisms of ED in the penile aging process in experimental and clinical data. It also highlights areas that are in need of more research. The search strategies yielded total records screened from PubMed. Clarification of the molecular mechanisms that accompanies corpus cavernosum aging and aging-associated ED will aid new perspectives in the development of novel mechanism-based therapeutic approaches. Age is not a limiting factor for ED medical management, and it is never too late to treat. Hypogonadism should be managed regardless of age, and synergistic effects have been found during testosterone (T) replacement therapy when used along with oral phosphodiesterase-5 (PDE-5) inhibitors. Therefore, the clinical management of ED related to aging can be done by therapeutic interventions that include PDE-5 inhibitors, and other pharmacological treatments.  相似文献   
977.
The duration of children's attention to putative threat has been documented as a consistent predictor of later anxiety in inhibited children across childhood (Fox, New Directions for Child and Adolescent Development, 127, 2010, 33; Pérez‐Edgar & Fox, Child and Adolescent Psychiatric Clinics of North America, 14, 2005, 681). However, attention to threat has not been broadly examined within existing behavioral contexts and has seldom been studied in very early childhood. Whereas toddlers with high levels of internalizing behavior may view fear‐inducing stimuli as a threat, toddlers with high levels of externalizing behavior may demonstrate attention out of interest or sensation seeking. Thus, attention to threat was expected to predict increased toddler shyness in the context of either high internalizing problems or low externalizing behavior. We examined 117 twenty‐four‐month‐old toddlers to determine whether attention to threat interacted with internalizing and externalizing behavior at 24 months of age to predict toddler shyness one year later. Results indicated that attention to threat predicted toddlers' lower shyness at 36 months when toddlers’ externalizing behavior at age 24 months were high, but there was no significant interaction between toddlers’ internalizing behavior and their attention to threat in predicting later shyness. These results expand our understanding of the contexts in which attention to threat in early childhood is a viable predictor of later shyness.  相似文献   
978.
Little research has examined the impact of maternal lifetime trauma exposure on infant temperament. We examined associations between maternal trauma history and infant negative affectivity and modification by prenatal cortisol exposure in a sociodemographically diverse sample of mother–infant dyads. During pregnancy, mothers completed measures of lifetime trauma exposure and current stressors. Third‐trimester cortisol output was assessed from maternal hair. When infants were 6 months old, mothers completed the Infant Behavior Questionnaire‐Revised. In analyses that controlled for infant sex and maternal age, education, race/ethnicity, and stress during pregnancy, greater maternal trauma exposure was associated with increased infant distress to limitations and sadness. Higher and lower prenatal cortisol exposure modified the magnitude and direction of association between maternal trauma history and infant rate of recovery from arousal. The association between maternal trauma history and infant distress to limitations was somewhat stronger among infants exposed to higher levels of prenatal cortisol. The analyses suggested that maternal lifetime trauma exposure is associated with several domains of infant negative affectivity independently of maternal stress exposures during pregnancy and that some of these associations may be modified by prenatal cortisol exposure. The findings have implications for understanding the intergenerational impact of trauma exposure on child developmental outcomes.  相似文献   
979.
We interviewed 18 family caregivers about their communication experiences in the ICUs at an urban hospital. Analysis of their narratives suggests health literacy is important in family caregiver/healthcare provider communication, especially as complicated illnesses move the caregiver deeper into decision making. Using the domains of Yuen et al.’s conceptual model of caregiver health literacy (2015), we identified three themes within the context of ICU communication: agency, coordinated communication, and caregiver’s evolving role. We saw family caregivers negotiating domains of health literacy as they built upon knowledge of the patient’s needs, their rights as family caregivers, and the hierarchy of the professional staff. We found that these narratives represent co-created, or relational communication, rather than individual health literacy skills. Conceptualized in the transaction of relationship, health literacy is enacted; it is socially constructed and is the scaffolding upon which family caregivers make decisions, care for their loved one, and care for themselves.  相似文献   
980.
Framed by Relational Dialectics Theory, this study explores the ways adult, former foster children discursively construct meanings of “family.” Contrapuntal analysis of 24 interviews revealed two discourses as competing to constitute family: the Discourse of Family as Irreplaceable and Inescapable (Permanence) and the Discourse of Family as Performative Kinning (Performance). Permanence was constituted by themes of biology and historical connection, reifying normative understandings. Performance, comprised of role enactment, need for tolerance, and unconditional love, challenged the Permanence discourse. Throughout the narratives, Performance competed with Permanence for dominance, illustrating the cultural pervasiveness and power of Permanence yet, in some moments, privileging the marginalized Performance discourse. This discursive competition constructed meanings of family in narratives of life before, during, and after foster care. Overall, participant’s talk constructed complex webs of family relationships, allowing access to an important social institution—family—regardless of the presence/absence of culturally valued markers of family (e.g., biology, legality).  相似文献   
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