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291.
Fred Luthans James B. Avey Bruce J. Avolio Steven M. Norman Gwendolyn M. Combs 《组织行为杂志》2006,27(3):387-393
After first providing the meaning of psychological capital (PsyCap), we present a micro‐intervention to develop it. Drawn from hope, optimism, efficacy, and resiliency development, this PsyCap Intervention (PCI) is shown to have preliminary support for not only increasing participants' PsyCap, but also financial impact and high return on investment. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
292.
293.
Summary It is possible to distinguish four target groups for tertiary environmental education: the Technical Group, the Subject Specialist Group, the Management Group and the Lay Group. Each of these groups requires different sets of skills and abilities. The Technical Group needs to know how to measure environmental parameters. The Subject Specialist Group needs to know about environmental systems. The Management Group needs to have the skills and abilities to resolve complex environmental issues and problems. The Lay Group needs to have attitudes, philosophies and values about the environment. Each of these in turn require different teaching strategies. For the Technical Group, practical experimental teaching methods based on the traditional subject approach appear to be the most suitable. The Subject Specialist Group needs presentational methods based on either an infusion approach or a new subject approach. For the Management Group, a combination of high level disciplinary teaching combined with intensive short skills courses and more extensive junctions or environmental encounters, all of which make use of practice methods of teaching, are suggested. For the Lay Group, experiential methods, where the student's attitudes are challenged by experiences in either an in-service situation or through simulation exercises, seem to be most appropriate.Dr David Stokes is Dean of the Faculty of Applied Science and Head of the Department of Environmental Studies at Victoria College, and Bruce Crawshaw is currently a lecturer seconded to the Universiti Pertanian Malaysia. 相似文献
294.
Michael Bruce BECK Rodrigo VILLARROEL WALKER 《Frontiers of Environmental Science & Engineering》2013,7(5):640-657
Nexus security is a compound mix of ideas: reconciling human needs and wants with access to multiple resources; diversity of access to those resources and services; resilience in the face of weather- and climaterelated variability; resilience likewise in the face of infrastructure failure; and the personal, individual sense of belonging. At the level of Systems Thinking there is a very close relationship between resilience in the behavior of natural (ecological) systems and resilience in the social dynamics of governance within communities, where such resilience establishes the viability of these communities over centuries, which in turn entails successful stewardship of the man-environment relationship. We use insights from this cross-system mapping — across natural, built, and human systems — to assess, first, the role of city governance in achieving nexus security (or not) and, second, the role of technological innovations in serving the same purpose. More specifically, eight principles, covering resilience and diversity of access to resources and services, are used to gauge security-enhancing features of city buildings and infrastructure. Case studies include new designs of resilient office blocks, nutrient (nitrogen and phosphorus) recovery systems for sanitation and wastewater treatment, and the reconstruction of urban parks for the provision of ecosystem services. Throughout the paper, matters of risk in the face of meteorological variability are prominent. We do not conclude, however, that the presence of risk implies nexus insecurity. 相似文献
295.
Marine reserves have become widely used in biodiversity conservation and are increasingly proposed as fisheries management tools. Previous modeling studies have found that reserves may increase or decrease yields, depending on local environmental conditions and on the specific life-history traits of the fishery species. Sex-changing (female-to-male) fish are targets of some of the most important commercial and recreational fisheries in the world. The potential for disproportionate removal of the larger, older sex of such species requires new theory to facilitate our understanding of how reserves will affect the yields of surrounding fisheries, relative to fishes with separate sexes. We investigated this question by modeling the effects of marine reserves on a non-sex-changing and a sex-changing population. We used demographic parameter estimates for the common coral trout as a baseline, and we conducted extensive sensitivity analyses to determine how sustainable yields of sex-changing species are likely to be affected by reserves across a broad range of life-history parameters. Our findings indicate that fisheries for sex-changing species are unlikely to receive the same yield-enhancing benefit that non-sex-changing fisheries enjoy from marine reserves, and that often reserves tend to reduce sustainable yields for a given overall population size. Specifically, the increased egg production and high fertilization success within reserves is more than offset by the reduced egg production and fertilization success in the fished areas, relative to a system in which fishing mortality is distributed more evenly over the entire system. A key reason for this appears to be that fertilization success is reduced, on average, when males are unevenly distributed among subpopulations, as is the case when reserves are present. These findings suggests that, for sex-changing populations, reserves are more suited to rebuilding overfished populations and sustaining fishery viability, rather than enhancing fishery yields. These results are robust over a range of sex-change regimes, stock-recruitment relationships, adult mortality rates, individual growth strategies, and fertilization-success functions. Our findings highlight the importance of considering the different contributions of males and females to population growth and fishery yields when evaluating the efficacy of marine reserves for enhancement of fished species. 相似文献
296.
We investigate work motivation in the unstudied domain of individuals who pursue very long‐term goals. We highlight the fact that the preponderance of research findings on the psychology of work motivation is based on short‐term studies and discuss the potential relevance to long‐term motivation of literatures including long‐term thinking and time horizons, long‐term goals and goal pursuit, and self‐regulation. We adopt the qualitative research strategy of theory elaboration, with a specific intention of elaborating goal‐setting theory. Analysis of interview data from a unique sample of scientists and others pursuing goals spanning decades or more yielded a structure of psychological factors that can enhance, support, and sustain motivation for the long term. Reconciling our findings with existing goal theories, we develop an integrative model of motivating factors and self‐regulation processes underlying long‐term goal pursuit. We discuss the implications, including an expanded focus for our field on motivating people for the long run. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
297.
Holly F. Swift William M. Hamner Bruce H. Robison Laurence P. Madin 《Marine Biology》2009,156(5):1049-1056
Behavioral observations using a remotely operated vehicle (ROV) in the Gulf of California in March, 2003, provided insights
into the vertical distribution, feeding and anatomy of the rare and delicate ctenophore Thalassocalyce inconstans. Additional archived ROV video records from the Monterey Bay Aquarium Research Institute of 288 sightings of T. inconstans and 2,437 individual observations of euphausiids in the Gulf of California and Monterey Canyon between 1989 and 2005 were
examined to determine ctenophore and euphausiid prey depth distributions with respect to temperature and dissolved oxygen
concentration [dO]. In the Gulf of California most ctenophores (96.9%) were above 350 m, the top of the oxygen minimum layer.
In Monterey Canyon the ctenophores were more widely distributed throughout the water column, including the hypoxic zone, to
depths as great as 3,500 m. Computer-aided behavioral analysis of two video records of the capture of euphausiids by T. inconstans showed that the ctenophore contracted its bell almost instantly (0.5 s), transforming its flattened, hemispherical resting
shape into a closed bi-lobed globe in which seawater and prey were engulfed. Euphausiids entrapped within the globe displayed
a previously undescribed escape response for krill (‘probing behavior’), in which they hovered and gently probed the inner
surfaces of the globe with antennae without stimulating further contraction by the ctenophore. Such rapid bell contraction
could be effected only by a peripheral sphincter muscle even though the presence of circumferential ring musculature was unknown
for the Phylum Ctenophora. Thereafter, several live T. inconstans were collected by hand off Barbados and microscopic observations confirmed that assumption. 相似文献
298.
The pelagic copepod Calanus pacificus ranges nearly continuously across temperate-boreal regions of the North Pacific Ocean and is currently divided into three
subspecies—C. pacificus oceanicus, C. pacificus californicus, C. pacificus pacificus—based on subtle morphological differences and geographic location. The relation between geography and genetic differentiation
was examined for 398 C. pacificus individuals sampled from six widely distributed locations across the North Pacific, including an open ocean site and coastal
sites on both sides of the North Pacific basin. For each individual copepod, the DNA sequence was determined for a 421-bp
region of the mitochondrial coxI gene (mtCOI). A total of sixty-three different mtCOI sequences, or haplotypes, were detected,
with a sequence divergence between haplotypes of 0.2–3.1%. The number and distribution of haplotypes varied with sampling
location; 12 haplotypes were distributed across multiple sampling locations, and 51 occurred at only one location. Five genetically
distinct populations were detected based on F
ST values. Haplotype minimum spanning networks, nucleotide divergence and F
ST values indicated that individuals from coastal sites in the North Pacific Ocean were more closely related to each other than
to individuals from the open ocean site at Station P. These results provide genetic support for the designation of two subspecies—a
coastal subspecies that consists of what is currently referred to as C. p. pacificus and C. p. californicus and an open ocean subspecies C. p. oceanicus. This work also indicates that planktonic copepods with potentially high dispersal capacity can develop genetically structured
populations in the absence of obvious geographic barriers between proximate locales within an ocean basin. 相似文献
299.
A combination of the urban heat island effect and a rising temperature baseline resulting from global climate change inequitably impacts socially vulnerable populations residing in urban areas. This article examines racial/ethnic and socioeconomic inequities in the spatial distribution of exposure to urban heat in the context of climate justice and residential segregation in the U.S. An urban heat risk index (UHRI) is calculated from measures of land surface temperature, structural density, and vegetation abundance, acquired from summer 2010 remote sensing imagery. Twenty of the largest metropolitan statistical areas (MSAs) in the U.S. are selected and analysed using census tract-level socio-demographic data from the U.S. Census. Multilevel modelling is utilised to examine the statistical associations between urban heat, minority status, socioeconomic disadvantage, and MSA-level segregation of racial/ethnic minority groups. Variables representing socioeconomic status (i.e. household income, home ownership, and education level) are consistently and significantly associated with greater urban heat exposure. Minority status and measures of segregation have a significant but varied relationship with urban heat exposure, indicating that there are inconsistent associations with urban heat due to differing social geographies. Urban heat and social vulnerability present a varying landscape of thermal inequity in different metropolitan areas, associated in many cases with residential segregation. 相似文献
300.
Bruce A. Hendry 《Environmental geochemistry and health》2010,32(4):353-359
This contribution to the International Congress on Production of Safe Water, Izmir, Turkey, 20–24 January, 2009, relates to
general aspects of a water supply undertaking rather than to particular technologies or chemistries for water treatment. The
paper offers a “creative problem solving” approach following Fogler and LeBlanc (Strategies for creative problem solving.
Prentice Hall, NJ, 1995) as a model for generating sustainable solutions when water quality and safety problems arise. Such a structured approach
presents a systematic methodology that can promote communication and goal-sharing across the inter-related, but often isolated
and dispersed, functions of water scientists and researchers, engineers, operations managers, government departments and communities.
A problem-solving strategy, or “heuristic”, invokes five main steps (define; generate; decide; implement; evaluate). Associated
with each step are various creative and enabling techniques, many of which are quite familiar to us in one form or another,
but which we can use more effectively in combination and through our increased awareness and practice. For example, taking
a fresh view of a problem can be promoted by a variety of “lateral thinking” tools. First-hand investigation of a problem
can trigger new thinking about the real problem and its origins. A good strategy implementation will always address each and every step (though not necessarily every possible technique) and will use them at various stages in the search for and implementation of solutions. The creative nature of our experience
with a problem-solving heuristic develops our facility to cope better with complex formal situations, as well as with less
formal or everyday problem situations. A few anecdotes are presented that illustrate some of the author’s experiences relating
to factors involved in safe water supply. Here, the term “factors” may signify people and organisations as agents, as well as meaning those aspects of a problem situation that need to be taken into account. 相似文献