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61.
Idiosyncratic deals in contemporary organizations: A qualitative and meta‐analytical review 下载免费PDF全文
Idiosyncratic deals (i‐deals) research focuses on the emergence of customized work arrangements employees negotiate with their employers. This article provides a critical review and synthesis of i‐deals research, combining a qualitative review of i‐deals theory and research with a supplementary meta‐analysis of 23 empirical studies (k = 27 samples, N = 8110 individuals). The qualitative review examines the conceptualization and measurement of i‐deals and identifies patterns and gaps in i‐deals research, while the quantitative meta‐analysis tests the moderating effect of societal cultures on the predictors and consequences of ideals investigated to date. In each section, attention is given to strengths and weaknesses of current approaches to i‐deals theory and research. Future research directions are identified with particular emphasis on the largely unexamined role of i‐deals from a multilevel perspective. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
62.
63.
Early non-invasive fetal sexing is widely available over the Internet, leading to concerns about its possible use for sex selection. The aim of this review is to summarise the results of surveys describing lay attitudes towards sex selection for non-medical reasons to help address or inform such concerns. A search of electronic databases and key journals was supplemented by an Internet search and citation-tracking. Twenty-one quantitative studies were identified. Most were conducted in the US, with five recent studies in the UK and Germany. Most studies found that, overall, people were not in favour of sex selection. However, this varied from 94 to 18%. People may hold more negative attitudes when the method of sex selection is specified, particularly if this involves termination of pregnancy (TOP). Attitudes towards the general availability of sex selection are less negative than those towards personal use. Attitudes were consistently negative in German surveys. Little is known of such attitudes outside the US, the UK and Germany, and how such attitudes may change as new sex selection technologies become available. Studies of use of early non-invasive fetal sexing for sex selection for non-medical reasons are needed to assess the extent to which concerns about usage are justified and to assist in debates on how these might be most appropriately addressed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
64.
Jay D. Evans 《Behavioral ecology and sociobiology》1996,39(4):275-284
In many polygynous ant species, established colonies adopt new queens secondarily. Conflicts over queen adoption might arise
between queens and workers of established colonies and the newly mated females seeking adoption into nests. Colony members
are predicted to base adoption decisions on their relatednesses to other participants, on competition between queens for colony
resources, and on the effects that adopted queens have on colony survivorship and productivity. To provide a better understanding
of queen-adoption dynamics in a facultatively polygynous ant, colonies of Myrmica tahoensis were observed in the field for 4 consecutive years and analyzed genetically using highly polymorphic microsatellite DNA markers.
The extreme rarity of newly founded colonies suggests that most newly mated queens that succeed do so by entering established
nests. Queens are closely related on average (rˉ = 0.58), although a sizable minority of queen pairs (29%) are not close relatives. An experiment involving transfers of queens
among nests showed that queens are often accepted by workers to which they are completely unrelated. Average queen numbers
estimated from nest excavations (harmonic mean = 1.4) are broadly similar to effective queen numbers inferred from the genetic
relatedness of colony members, suggesting that reproductive skew is low in this species. Queens appear to have reproductive
lifespans of only 1 or 2 years. As a result, queens transmit a substantial fraction of their genes posthumously (through the
reproduction of related nestmates), in comparison to direct and indirect reproduction while they are alive. Thus queens and
other colony members should often accept new queens when doing so will increase colony survivorship, in some cases even when
the adopted queens are not close relatives.
Received: 20 February 1996/Accepted after revision: 25 May 1996 相似文献
65.
Most of the world's children live in resource-poor countries where people are at a relatively high risk of exposure to catastrophic situations arising from conflict and natural disasters.(6) Given the potential social, psychological and psychiatric consequences of exposure to disaster, mental health and psychosocial support programmes are increasingly part of humanitarian aid. A minimum standard on mental and social aspects of health is included in the recently revised Humanitarian Charter and Minimum Standards in Disaster Response (Sphere Handbook) (Sphere Project, 2004). Most recommendations for mental health and psychosocial interventions in guidance documents are based on expert opinion rather than research. Consequently, interventions are being implemented without full understanding of their potential benefit or harm. This paper offers a child-focused review of the evidence for each of the interventions described as indicators for the Sphere standard on mental and social aspects of health. It suggests some, but limited, support for each of them. However, the evidence base needs substantial strengthening. 相似文献
66.
Crowding and Experience-Use History: A Study of the Moderating Effect of Place Attachment Among Water-Based Recreationists 总被引:1,自引:1,他引:0
Effective recreation resource management relies on understanding visitor perceptions and behaviors. Given current and increasing
pressures on water resources, understanding crowding evaluations seems important. Beyond crowding, however, variables that
possibly relate to or influence crowding are of interest and in particular, place attachment and experience-use history (EUH).
As EUH is related to place attachment and likely affects crowding, this study explored the moderating effect of place attachment
dimensions on the relationships between EUH and visitor crowding evaluations. Water based recreationists at a U.S. Army Corps
of Engineers site were contacted onsite and asked questions related to experience-use history, crowding evaluations, place
attachment, and activity participation. Anglers and campers at the site identified similar crowding perceptions and place
attachments. Only one of eight models tested revealed a moderating effect. Specifically, place identity moderated the relationship
between the total times visited in the past twelve months and expected crowding among anglers. As such, the quest continues
to understand the relationship among these important variables. 相似文献
67.
Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease
in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation
and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future
water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion.
To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and
salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model
indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early
life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing
our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the
recovery of the Savannah River striped bass population. The available salinity data were collected during average and low
flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is
a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine
salinity regime and points to areas of concern and potential future research. 相似文献
68.
减灾事业的发展和综合减灾 总被引:14,自引:1,他引:14
中国减灾事业的发展史可分3个阶段:第一阶段是新中国成立以前的几千年,减灾活动以赈灾为主,帝王“祭天求恕”,“防灾吏制”,安抚于民。清末民初1800至1949年间计发生巨灾25起,死亡4993万余人,总灾亡则近亿,年均灾亡60万人以上,这段惨痛的灾况记下了十分难得的灾情史,泣血于残野。新中国成立后,在“为人民服务”的思想指导下,为减轻灾害损失,逐步建立了气象、水利、农林、地震、海洋、地质等专业的灾害科技与减灾工程,政府并组织社会兼事抗灾、救灾、应急减灾,国家减灾实力快速增长,已取得突出减灾实效,这个阶段比第一阶段灾亡人数下降了90%以上,但年均灾亡人口仍有1.2万人左右。该阶段的工作特点是以单灾种纵向体系为主,不同灾类的监测、预报水平尚高低不一,这与成灾机理的难易程度和工作条件的强弱有关。21世纪初,随全球增温之势锐升,多类极端灾变遍及各洲,促使许多国家发动全社会人众共同探求“综合减灾”之路;我国政府已迅即开展全社会应急减灾行动,开启了“综合减灾”之先声,这是减灾事业步入第三阶段的先导。综合减灾应该是全社会相关部门和民众的统一行动。目前尚有3个问题需要弄清楚,一是多种自然灾害之间成灾机理相关性的研究,其对象是灾害群与灾害链;二是全社会减灾要素综合运作预案的优选;三是如何核算减灾投入与社会可持续发展之正、负效应关系。 相似文献
69.
近场地震作用下框架结构的损伤机理 总被引:1,自引:0,他引:1
首先讨论了近场地面运动的特征及各种抗震规范对近场地震的设防,然后采用非线性时程分析方法,对一个10层框架结构在近场地震作用下的响应特性进行了研究。同时对该框架结构进行了Pushover分析,通过与非线性时程分析结果进行对比,说明Pushover分析方法不能正确评估结构在近场地震作用下的抗震性能。 相似文献
70.
通过引入应变速率、损伤变量以及刚度退化指标等参数,建立了应变率相关的混凝土弹塑性损伤模型。运用该模型对某重力坝厂房坝段分别就率相关及率无关两种情况进行了三维非线性地震响应时程分析。深入研究了混凝土应变速率等相关特性对结构动力响应的影响。结果表明,应变速率对混凝土的力学性能有一定的影响,随着应变速率的增加,坝体结构的变形减小,主拉应力有所提高,应变能有所减小以及开裂损伤有一定的降低。所得结论对混凝土重力坝的震害研究有一定的参考价值。 相似文献