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1.
Many studies have provided evidence that, in birds, inexperienced breeders have a lower probability of breeding successfully. This is often explained by lack of skills and knowledge, and sometimes late laying dates in the first breeding attempt. There is growing evidence that in many species with deferred reproduction, some prebreeders attend breeding places, acquire territories and form pairs. Several behavioural tactics assumed to be associated with territory acquisition have been described in different species. These tactics may influence the probability of recruiting in the breeding segment of the population, age of first breeding, and reproductive success in the first breeding attempt. Here we addressed the influence of behaviour ('squatting') during the prebreeding period on demographic parameters (survival and recruitment probability) in a long-lived colonial seabird species: the kittiwake. We also investigated the influence of behaviour on reproductive trajectory. Squatters have a higher survival and recruitment probability, and a higher probability of breeding successfully in the first breeding attempt in all age-classes where this category is represented. The influence of behaviour is mainly expressed in the first reproduction. However, there is a relationship between breeding success in the first occasion and subsequent occasions. The influence of breeding success in the first breeding attempt on the rest of the trajectory may indirectly reflect the influence of behaviour on breeding success in the first occasion. The shape of the reproductive trajectory is influenced by behaviour and age of first breeding. There is substantial individual variation from the mean reproductive trajectory, which is accounted for by heterogeneity in performance among individuals in the first attempt, but there is no evidence of individual heterogeneity in the rate of change over time in performance in subsequent breeding occasions  相似文献   
2.
Many studies have provided evidence that, in birds, inexperienced breeders have a lower probability of breeding successfully. This is often explained by lack of skills and knowledge, and sometimes late laying dates in the first breeding attempt. There is growing evidence that in many species with deferred reproduction, some prebreeders attend breeding places, acquire territories and form pairs. Several behavioural tactics assumed to be associated with territory acquisition have been described in different species. These tactics may influence the probability of recruiting in the breeding segment of the population, age of first breeding, and reproductive success in the first breeding attempt. Here we addressed the influence of behaviour ('squatting') during the prebreeding period on demographic parameters (survival and recruitment probability) in a long-lived colonial seabird species: the kittiwake. We also investigated the influence of behaviour on reproductive trajectory. Squatters have a higher survival and recruitment probability, and a higher probability of breeding successfully in the first breeding attempt in all age-classes where this category is represented. The influence of behaviour is mainly expressed in the first reproduction. However, there is a relationship between breeding success in the first occasion and subsequent occasions. The influence of breeding success in the first breeding attempt on the rest of the trajectory may indirectly reflect the influence of behaviour on breeding success in the first occasion. The shape of the reproductive trajectory is influenced by behaviour and age of first breeding. There is substantial individual variation from the mean reproductive trajectory, which is accounted for by heterogeneity in performance among individuals in the first attempt, but there is no evidence of individual heterogeneity in the rate of change over time in performance in subsequent breeding occasions  相似文献   
3.

Literature on informal political institutions has focused on the national level, disregarding sub-national contexts where one can expect increased informality. This article analyzes locally allocated Chilean public investment to understand how informal institutions affect regional development and local democracy. Based on 59 interviews with key stakeholders and national authorities, this research analyses the flow of the decision-making process on funds for regional investment. The results show that local bureaucrats introduce innovations to cope with the weaknesses of formal decision-making regulations, and that these may become informal institutions that complement or accommodate the process to obtain the outcomes expected under the formal rule.

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4.
Due to the increase of production costs in manual harvesting, strategies must be developed in order to overcome these effects, such as the attempts in implementing agricultural machines in harvest activities, whether being totally or partially mechanized. This study brings a qualitative and quantitative comparison on the impacts in work conditions and productivity in Brazilian orchards caused by the use of semi-mechanized harvesting systems, such as multiplatforms. The results come from the application of Ergonomic Work Analysis method, which focuses in the activity, quantifying and analyzing times and frequencies of the harvesting cycle, as well as the amount of movements. To achieve this, footage, interviews and a stopwatch were used in the observation 12 pickers' work cycles, six for each method of harvesting. The data interpretation pointed to improvement in working conditions with a reduction in the amount of movements performed by the picker, and increase of up to 60% in productivity with the use of semi-mechanized harvesting. Thus, the found results indicate the viability of this harvesting method. However, other variables must be observed in future studies in order to complete the guidelines for a healthy progress in the area of citrus harvesting in Brazil.  相似文献   
5.
The purpose of this paper is to explain why low-wage workers with identical qualifications to higher-wage workers are more exposed to unemployment. Each worker is considered to belong to a social group (defined according to his/her gender, age, and nationality). We assume that workers experience both productive interdependencies and social interactions within the firm. Also inter- and intra-group interactions determine worker productivity, and frictions on the labor market limit the hiring of the most productive workers. Consequently, externalities acting both within the firm and in the labor market can lead to a higher rate of unemployment for low-wage workers.  相似文献   
6.
Multi-state models help predict future numbers of patients requiring specific treatments but these models require exhaustive incidence data. Deriving reliable predictions from repeated-prevalence data would be helpful. A new method to model the number of patients that switch between therapeutic modalities using repeated-prevalence data is presented and illustrated. The parameters and goodness of fit obtained with the new method and repeated-prevalence data were compared to those obtained with the classical method and incidence data. The multi-state model parameters’ confidence intervals obtained with annually collected repeated-prevalence data were wider than those obtained with incidence data and six out of nine pairs of confidence intervals did not overlap. However, most parameters were of the same order of magnitude and the predicted patient distributions among various renal replacement therapies were similar regardless of the type of data used. In the absence of incidence data, a multi-state model can still be successfully built with annually collected repeated-prevalence data to predict the numbers of patients requiring specific treatments. This modeling technique can be extended to other chronic diseases.  相似文献   
7.
The medicalisation of aging and old age constructs ageing as first and foremost a biomedical event and as a process of inevitable decline. In sports science and sports medicine the functional decrements normally associated with ageing are being addressed. There is evidence reported in the scientific literature suggesting that certain exercise interventions can ‘reduc[e] or prevent[…] functional declines linked to secondary aging’ [Goggin, N.L., and Morrow, J.R. Jr. (2001). "Physical Activity Behaviors of Older Adults." Journal of Aging and Physical Activity 9, 58–66.].However a sociological critique is necessary. Whilst sports science seeks to position itself as a key player in the fight against ageing, it also opens the potential for the reconstruction of the ageing body as fit. However the evidence that exercise can fundamentally reshape older bodies is equivocal. A new frame is proposed which divorces exercise from anti-ageing purposes and uses the science of exercise to enable older people to recover a sense of physical competence as a creative pursuit in its own right.  相似文献   
8.
Disability is a crucial health and social concern in sub‐Saharan Africa, where a high prevalence of disabling diseases is compounded with insufficient care provision. There is a need for detailed analysis of the disability patterns. We provide a gender‐specific picture for the population in peripheral Ouagadougou (Burkina‐Faso), based on six disability dimensions following the United Nations’ recommendations. We computed disability‐free life expectancy (LE) using the Health and Demographic Surveillance System (Ouaga HDSS) (n = 1 902). Women have a longer partial LE in the 20–79 age range (+3.3 years), half of this LE being spent with a disability, versus 31% of the LE for men. Limitations in mobility, cognition, and eyesight occur in midadulthood and result in a considerable disadvantage for women in the number of years with these limitations. These findings highlight disability patterns that are detrimental to social participation and claim for better screening and care, especially for women.  相似文献   
9.
We examined the potential role of three mediators—sexual self-esteem, sexual anxiety, and sexual assertiveness—of the association between romantic attachment insecurities (anxiety and avoidance) and two aspects of women's sexual functioning: sexual function and sexual satisfaction. A sample of 556 women aged 18 to 30 agreed to complete an online series of validated questionnaires assessing attachment insecurities and several aspects of sexual functioning. Lower sexual self-esteem and higher sexual anxiety mediated the associations between attachment anxiety and lower sexual function and satisfaction. Lower sexual self-esteem and higher sexual anxiety also partially mediated the links between attachment-related avoidance and the two sexual functioning variables. Sexual assertiveness, however, did not mediate these associations. A significant interaction between attachment anxiety and avoidance was also found to predict sexual satisfaction, with women high in avoidance and low in anxiety being the least satisfied. Results are discussed in terms of theoretical and clinical implications.  相似文献   
10.
We study the consequences of the coexistence of different social protection systems on contribution rate levels and migration in a two-country model. Before any migration takes place, the levels of contribution rates are chosen by a representative elected in each country. The migration of each agent depends on her anticipation of other agents’ migrations. We show that the richest agents are attracted to the Bismarckian country. The poorest agents tend to migrate toward one country or the other depending on the Beveridgean country contribution rate. The Beveridgean country can set a higher contribution rate to limit the departures of rich agents.
Emmanuelle TaugourdeauEmail: Fax: +33-2-31566260
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