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991.
S. T. A. Pickett M. L. Cadenasso E. J. Rosi-Marshall K. T. Belt P. M. Groffman J. M. Grove E. G. Irwin S. S. Kaushal S. L. LaDeau C. H. Nilon C. M. Swan P. S. Warren 《Urban Ecosystems》2017,20(1):1-14
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
992.
Introduction: The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men.Methods: 22 lifetime sedentary (SED; 62?±?2 years) and 17 masters’ athletes (LEX; 60?±?5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay.Results: IGF-I was higher in LEX compared to SED at baseline (p?=?0.007, Cohen’s d?=?0.91), and phase B (p?=?0.083, Cohen’s d?=?0.59), with only a small difference at C (p?=?0.291, Cohen’s d?=?0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1?±?4.7 to 14.2?±?6.0?μg·dl?1 (p?=?0.376, Cohen’s d?=?0.22), followed by a larger increase post-HIIT (16.9?±?4.4?μg·dl?1), which was significantly elevated compared with baseline (p?=?0.002, Cohen’s d?=?0.85), and post-preconditioning (p?=?0.005, Cohen’s d?=?0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2?±?6.4 to 17.2?±?3.7?μg·dl?1 [p?=?0.538, Cohen’s d?=?0.19]), and a small change post-HIIT (18.4?±?4.1?μg·dl?1 [p?=?0.283, Cohen’s d?=?0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p?0.05, Cohen’s d?=?0.32–0.45).Conclusions: In conclusion, HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX. 相似文献
993.
Hussin M. Mutalib 《Asian Ethnicity》2017,18(1):54-73
Many governments, in their zeal to progress and deliver the fruits of development, are caught in a web of unsavory habits and practices that impair not only their international image but also domestic legitimacy. One such perennially persistent and resilient disease is ‘money politics.’ Taking Malaysia as a case study, we note that despite sustaining a remarkable record of economic and multiethnic stability, the country has also been helpless in mitigating this obstinate issue. In this article, it is posited that the phenomenon is not a new or recent portent but has actually persisted even prior to independence. We shall then contend that unless the ruling Barisan Nasional (BN) coalition government attaches greater priority in stamping out this political bug, the country’s otherwise enviable development trajectory and the quest to reach a ‘developed nation’ status via its Vision 2020 declaration, even if fulfilled, are not cause for celebration, given its implications to the country’s economic sustainability and multiethnic stability. 相似文献
994.
Mary Kate Dennis Edward T. Scanlon Alicia M. Sellon 《Journal of Religion & Spirituality in Social Work》2017,36(4):456-478
Food insecurity is a common social issue and households look to assistance from food pantries, which often have difficulty supplying fresh or nutritious food. A substantial amount of produce is left in the fields, which can be collected through gleaning. In a focus group with volunteer gleaners at a faith-based nonprofit organization that attempts to fill the gaps of food insecurity, the motivations, challenges, and benefits of volunteering were examined. Volunteering in gleaning generated a sense of collective purpose and community; it addressed deeply held religious and spiritual impulses; and it puts volunteers directly in contact with nature. 相似文献
995.
E. C. M. Mason Sarah I. Springer Ashley Pugliese 《Journal of LGBT Issues in Counseling》2017,11(4):301-318
ABSTRACTThis article posits that an integrative research partnership model can assist school counselors in addressing the marginalization of transgender students in schools through staff development. A methodological integration of action research and program evaluation through quantitative and qualitative data collection is explained, and a collaborative process is highlighted. A case example is provided to demonstrate the use of the design. 相似文献
996.
ABSTRACTDespite increasing societal acceptance of sexual-minority individuals, there are still gay, lesbian, and bisexual (GLB) adolescents who experience negative mental health outcomes. Minority stress theory posits that stigma-related stress associated with sexual-minority status drives increased risk among GLB individuals. Furthermore, recent evidence suggests that minority stress impacts emotion regulation (ER), identified as a particularly important risk factor for sexual-minority youth (SMY). Current research has identified some aspects of parenting contribute to GLB youth's mental health. We review the literature in these areas, and also integrate research from the broader developmental field on families and emotion socialization in order to identify the need for studies of parenting that go beyond existing data on parental acceptance and supportiveness of youth's sexual orientation. Limitations of the current literature and directions for future research are discussed, with specific focus on implications for interventions with SMY and their families. 相似文献
997.
Female genital cutting (FGC) is a persistent social norm in the Liben district of southern Ethiopia. This study explores whether the sexual experiences of married men and women differ by women's FGC status. Qualitative in-depth interviews were conducted with 28 women with different types of FGC (or no FGC) and 21 husbands. Compared to others, women with more severe FGC reported traumatic sexual experiences and decreased sexual desire. Nonetheless, participants largely endorsed FGC for daughters, revealing pressure to maintain the practice. Opportunities for change exist, as women and men recognized the sexual pleasure and healthy birth experiences of uncut women. 相似文献
998.
Objectives: The authors conducted an initial validation of the Arizona Sexual Experience Scale (ASEX) and examined the sexual function of Spanish and Portuguese young adults. Methods: Participants were 523 Spanish and 595 Portuguese heterosexual young adults who completed a background questionnaire, the ASEX, and measures of sexual sensation seeking, excitation, and inhibition. Results: The ASEX showed good reliability and validity. Participants reported good sexual function. The most prevalent difficulties in men were related to desire and orgasm, and to orgasm and satisfaction in women. Conclusions: This is a psychometrically sound instrument to assess sexual functioning in Spanish and Portuguese young adults. 相似文献
999.
This study explores the impacts of HIV pre-exposure prophylaxis (PrEP) use on the sexual health of men who have sex with men (MSM). The authors conducted in-depth interviews with MSM who use PrEP (n = 14). Data was analyzed using interpretative phenomenological analysis. PrEP use reduced fear and shame associated with sex and facilitated greater sexual satisfaction and intimacy. Although participants generally viewed PrEP as empowering and beneficial, they also experienced PrEP-related stigma. The authors’ analysis emphasizes the importance of understanding the reasons MSM use PrEP and highlights opportunities for reducing harm and fostering sexual health among MSM who are using or considering PrEP. 相似文献
1000.
M. Hermanns 《Journal of Statistical Computation and Simulation》2017,87(3):607-630
Point and interval estimators for the scale parameter of the component lifetime distribution of a k-component parallel system are obtained when the component lifetimes are assumed to be independently and identically exponentially distributed. We prove that the maximum likelihood estimator of the scale parameter based on progressively Type-II censored system lifetimes is unique and can be obtained by a fixed-point iteration procedure. In particular, we illustrate that the Newton–Raphson method does not converge for any initial value. Furthermore, exact confidence intervals are constructed by a transformation using normalized spacings and other component lifetime distributions including Weibull distribution are discussed. 相似文献