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351.
Behavioural adaptations are recognized as crucial determinants for successful establishment and persistence of animal populations in a novel urban environment. Here, we examined mechanisms responsible for the development of urban behavioural type in a common waterbird, the Eurasian coot Fulica atra. We compared the behaviour of coots from a rural population and two urban populations that differed in the timing of colonization event (1960s vs. 2000s). We found that some behavioural characters associated with urban life (aggression during nest defence and boldness towards humans during foraging) were more strongly expressed in the older urban population when compared with the recently established urban population. By contrast, coots from the two urban populations showed a similar likelihood of exploiting human-derived food resources, as well as they showed similar levels of physiological stress. Urban coots were generally more aggressive, bolder, and less stressed than their rural conspecifics. Large behavioural and physiological divergence of coots from the recently established urban population and their rural conspecifics suggested that phenotypic plasticity and phenotype sorting may play a key role in the initial stages of urban colonization. On the other hand, increasing expression of boldness and aggression with the time since urbanization may suggest the role of microevolutionary adaptation in response to novel selective forces associated with the urban environment. Our results indicate that a combination of different processes (phenotypic plasticity, phenotype sorting, and microevolution) can determine successful colonization of urban areas by the Eurasian coots, and possibly other bird species.  相似文献   
352.
This study explored the experiences of mothers in college using a qualitative design. Results showed that a lack of financial resources was the chief barrier for student mothers in their educational pursuits while social/emotional support was the most important contributor to student mothers’ success in college. Participants relied heavily on student loans to cover costs of childcare or family to help watch their children. Role conflict experienced by student mothers has implications on family and college retention. Implications of this study included the adaptation and revisions of policies at the state and federal levels in addition to implications at the university level. Limitations of the study included a lack of racial and ethnic diversity and only including student mothers currently enrolled in college. Several recommendations for future research are described.  相似文献   
353.
A broad empirical literature asks if social policies designed to provide benefits to low-income families also affect family formation patterns. While most of the evidence suggests that family formation effects are small at best, and often nonexistent, recent research argues that policies that alter budget constraints considerably should have greater family formation impacts. We tested this hypothesis by investigating the Social Security Student Benefit Program (SSSBP), a program designed to provide large higher education subsidies for the children of disabled, retired, or deceased parents. Conditions for receipt of SSSBP created strong incentives to delay marriage. Utilizing data from the National Longitudinal Survey of Youth, 1979, and a difference-in-differences model, we found that women potentially qualifying for the SSSBP were much less likely to marry before age 22 and were older when they had children, while the program did not influence the probability of women ever marrying or having children. Impacts on men, however, were negligible.  相似文献   
354.
A common risk among adolescents is sexual solicitation, in which an adolescent is asked to provide sexual information, engage in sexual talk, or in sexual activities. Although scholars increasingly address this topic from an intrapersonal perspective, there is little attention to factors of language use and message content. In two focus group studies, we investigated whether adolescent girls consider themselves capable of assessing whether an online stranger is an adult or a peer, the extent to which adolescent girls actually succeed in making this assessment, the strategies they apply to do so, and the content- and language-related cues focused on. Our findings suggest that most of the adolescent girls are confident in their ability to assess whether the stranger is a peer or an adult with possible sexual intentions. However, we also found that only 43% were able to correctly make this assessment. Most of the adolescents seem to apply the passive strategy of uncertainty reduction: They scan the profile page of the stranger, check contact information, and the profile picture. They may choose to apply the interactive strategy to find out more about the online stranger. Important content-related cues that alarm adolescent girls are: ignoring personal questions, showing an exaggerated amount of interest, acting as a friend, and being sexually oriented. Language cues mentioned related to word usage, abbreviations, sentence length, and tone.  相似文献   
355.
The aim of this paper is to empirically study the effect of uncertainty on private consumption using a sample of Spanish households, and therefore, to test the existence of a precautionary motive for saving. Using data provided by the Spanish Survey of Household Finances and the Labour Force Survey we construct several uncertainty measures that are commonly used in the literature and an additional indicator based on job insecurity data, and we consequently estimate different econometric models under the life-cycle/permanent income hypothesis, including these measures of uncertainty. Our results are twofold: first, we find evidence in favour of the precautionary saving hypothesis. Secondly, we find that, unlike other variables related to the performance of the labour market (such as the unemployment rate) the job insecurity indicator is an appropriate variable to approximate income uncertainty in any macroeconomic context.  相似文献   
356.
Occupational health management and science increasingly focus on the issue of health-promoting leadership. Meanwhile a lot of leadership behaviors have been identified that affect the health of employees. To measure them requires high costs. Therefore, the aim of this study is to identify core-factors of salutogenic leadership and to operationalize them for an efficient diagnosis. As an integrative work-related indicator of employees’ health sense of work coherence (Work-SoC) was chosen. In a deductive and inductive process the TIMP-inventory has been developed that enables the economic assessment of three leadership dimensions: Trust, Incident Management and Pressure. These factors explain with less items more variance of the Work-SoC construct than established general and health-related leadership scales of transformational leadership, consideration, social support, demanding leadership as well as positive and negative health behavior. That is why the TIMP-factors can be recognized as core-factors of health-promoting leadership.  相似文献   
357.
Strategic human resource management has avoided to evaluate its efforts in relation to employees’ careers. Recent research has investigated a selection of individual human resource management (HRM) practices (e.?g., training and development, mentoring, career development, talent management, performance appraisal) in relation to objective and subjective career success, but failed to study HRM systems or bundles. This paper argues that HRM systems and career success can be connected via human capital theory because human capital is understood as an organizational resource and as an individual antecedent to careers. Based on extant research that relates individual HRM practices to objective or subjective career success, this paper reviews and discusses the relationship between bundles of HRM practices and the individual practices contained therein and career success. The final conclusion suggests that evaluations of HRM systems should take careers into account because organizations rely on employees’ human capital. Future research should focus more intensely on the role of HRM for the development of careers also across organizations.  相似文献   
358.
For the ?news‘ section of the journal ?Gruppe, Interaktion, Organisation (GIO)‘, Janine Klemmt inducts into the functioning of US conference formats, which have long-since spread to European conference landscape. Among them there are formats like BarCamp or the predecessor Open-Space-Technology. These formats increasingly rely on the active participation and involvement of their attendees. Occasionally, the conference content is completely locally determined by the attendees. These participatory conferences have a decentralized structure, which is similar to the way social media works, but cannot be explained by an imitation of contemporary social media formats. Rather by means of decentralization online and conference platforms have a common organizational component, a common denominator, which, especially with cybernetics, has moved into the field of science, has been taken up in societal areas such as technology and business, and thus increasingly found its way into the everyday world.  相似文献   
359.
In order to motivate and retain technical employees, representatives of strategic career management face the challenge of establishing alternative career paths in addition to the common leadership/management career. Surveying a sample of 629 doctorate holders from the STEM fields, we differentiated between five career paths within and beyond structured career models. Structured career ladders were predominantly present in major enterprises. Female participants less frequently reported to be part of a structured career path. Entering a leadership/management career seems to occur at a later stage compared to other paths. Generally, advancement on a leadership/management path was related to stronger increases in incentives than climbing up the technical/expert or project management ladders. Contrary to our expectations, we did not find members of a technical/expert career to work closer to basic research and their initial qualification than their colleagues on other career paths. Members of leadership/management paths reported to have significantly more leadership responsibility than those working on alternative paths.  相似文献   
360.
Up to 1987 the Spanish Income Tax imposed compulsory joint filing for married couples. However, the 1988 reform allowed spouses to choose between joint and separate taxation, involving a reduction in tax rates for secondary earners. Our aim is to analyze this reform as a quasi-natural experiment, assessing the effects of tax changes on labor participation. To find out the causal effect we adopt the difference-in-differences technique. We use data from the ‘Spanish Income Tax Panel 1982–1998’. Our results show that, as a consequence of differential tax changes, married women in families more strongly affected by the fiscal reform increase their labor participation more than secondary earners from families less affected by the reform. The participation rate for secondary earners in the treatment group increases by 9.4 percentage points whereas the control group increases their participation rate by 7.8 percentage points. We define the treatment group as those secondary earners in relatively low-income families in year 1987 and the control group as those in middle-high income families, because the former experiences a stronger reduction in tax rates than the latter. As a result, we can attribute the 1.6-percentage-point-increase in participation rates to the 1988 income tax reform.  相似文献   
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