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341.
We compared membrane thickness of fully developed eggs with those of non-developed eggs in different endangered falcon taxa. To our knowledge, membrane thickness variation during development has never been examined before in falcons or any other wild bird. Yet, the egg membrane constitutes an important protective barrier for the developing embryo. Because eggshell thinning is a general process that occurs during bird development, caused by calcium uptake by the embryo, eggs are expected to be less protected and vulnerable to breakage near the end of development. Thus, egg membranes could play an important protective role in the later stages of development by getting relatively thicker. We used linear mixed models to explore the variation in membrane thickness (n = 378 eggs) in relation to developmental stage, taxon, female age, mass and identity (73 females), egg-laying sequence (105 clutches) and the study zone. Our results are consistent with the prediction that egg membranes are thicker in fully developed eggs than in non-developed eggs, suggesting that the increase in membrane thickness during development may compensate for eggshell thinning. In addition, our data shown that thicker membranes are associated with larger, heavier and relatively wider eggs, as well as with eggs that had thinner eggshells. Egg-laying sequence, female age and the study zone did not explain the observed variation of membrane thickness in the falcon taxa studied. As we provide quantitative data on membrane thickness variation during development in falcons not subjected to contamination or food limitation (i.e. bred under captive conditions), our data may be used as a reference for studies on eggs from natural populations. Considering the large variation in membrane thickness and the multiple factors affecting on it and its importance in the protection of the embryo, we encourage other researchers to include measurements on membranes in studies exploring eggshell thickness variation.  相似文献   
342.
In recent years, new tools for funding nature conservation have been designed. Because poverty is often significant in areas with high biodiversity, the improvement of local livelihoods is frequently considered as a secondary goal of new financing mechanisms besides nature conservation. The buffer zone of the Podocarpus National Park in Ecuador is such a high biodiversity zone. In this paper, we compare the cost-effectiveness and development potential of three different mechanisms to finance nature conservation implemented in this buffer zone, namely (a) an organic coffee label, (b) the Socio Bosque Program, a nationwide payment scheme for private forest conservation, and (c) FORAGUA, a regional water fund. This paper describes the functioning and the scope of the mechanisms and analyses their environmental and socio-economic impacts which are compared to the total costs. Results show that the water fund has the highest additionality in ecosystem service provision, while the payment scheme is the most cost-effective both for current as for increased ecosystem service provision and for extra rural job creation. Organic coffee certification has the highest positive impact on rural income creation.  相似文献   
343.
This study was designed to evaluate the impact of sewage sludge spreading on tropical soilborne heavy metal speciation. Sludgeborne heavy metal speciation was also assessed, and the potential mobility of the elements was classified as follows: Zn>Ni>Cu approximately Cr. Two sequential extraction procedures were applied to study Cr, Cu, Ni and Zn speciation in control soils and sludge-amended soils. We demonstrated that sewage sludge spreading over a 2-year period did not have an impact on soilborne heavy metal concentrations but affected speciation of the most mobile fractions of Ni and Zn. Both protocols were consistent for the organic matter fractions, with an increase in Cu, Zn and Cr concentrations in the amended soil as compared to the control soil. In addition, we highlighted that the two protocols characterized different pools of organic matter and that organic compounds remained in the solid matrix after extraction. With respect to the reducible fraction, completely opposite results were obtained with the two protocols and the solid residue study revealed that the two schemes were ineffective in characterizing iron and manganese fractions.  相似文献   
344.
There is a growing ‘energy democracy’ (ED) movement which regards the transition to renewable energy as an opportunity for socio-economic transformation, as well as technological innovation. The literature on ED tends to associate greater democratic control of energy systems with increased community control over the means of energy generation and distribution. Nonetheless, this literature often assumes rather than demonstrates that the forms of governance it promotes are more democratic than the status quo. This analysis contributes to the emerging field of ED by assessing the complex and varied ways in which communities in Scotland practise energy governance. By focusing on three key governance processes (decision-making, accountability and dispute resolution), the importance of local contexts for the establishment and negotiation of democratic practices is demonstrated. This local specificity, however, also raises further questions regarding the universal applicability of the ED concept.  相似文献   
345.
346.
The relationship between health complaints and flexible work schedules was studied in a patient population selected by general practitioners. Four hundred and eighty patients between 20 and 60 years, currently employed or on sick leave, completed questionnaires which compiled data on their work situation, subjective physical health, psychological well‐being, and quality of sleep. Subjective health measurements were performed by using the 21‐item Subjective Health Questionnaire (VOEG). Psychological well‐being was measured by applying a selection of the Sickness Impact Profile. Duration and quality of sleep were measured through a selection of the Groningen Sleep Scale. Patients working rotating shifts, compressed weeks, and irregularly changing hours showed significantly more health complaints, more problems related to their psychological performance, and more sleeping problems than a control group of workers with non‐flexible work schedules. Patients working on temporary employment contracts reported significantly more problems with their psychological performance. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
347.
The purpose of the present research was to demonstrate that the perceived importance of wages is a function of thermal climate and national wealth. As hypothesized, analyses of 37 nationally representative samples of 22 483 blue‐ and white‐collar workers and 5544 managers show that wages are perceived as more important in poorer countries with colder climates (e.g., Azerbaijan) than in richer countries with colder climates (e.g., Canada) and in poorer and richer countries with temperate climates (e.g., Uganda, Singapore). The results suggest that performance‐related pay may be most effective in poorer countries with colder climates. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
348.
The purpose of this study is to develop a feature‐oriented assessment of psychological contracts, an underdeveloped approach to psychological contracts. Relying on theoretical frameworks in psychological contract research, industrial relations studies, and a cross‐national study on psychological contracts, we identify six dimensions that capture the nature of psychological contracts: tangibility, scope, stability, time frame, exchange symmetry, and contract level. We validate this expanded conceptualization of psychological contracts by developing a nomological network and testing it in a large, representative sample of 1106 employees. The results indicate the significance of formal contract characteristics and HR practices as two antecedents shaping the nature of psychological contracts. In addition, the hypothesized relationships between the three dimensions of time frame, exchange symmetry, and contract level with affective commitment are confirmed as well as the relationships between tangibility, scope and flexibility with personal control. The results further indicate the importance of assessing both employer and employee obligations given the differential effect of the contract makers. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
349.
In the literature on the relationship between participation in decision making and performance, a tell‐and‐sell strategy is considered a viable alternative to participation. In contrast, we argue that in organizational settings, when a sensitive and important issue is at stake, participation of a form to be characterized as formal, long term, direct, and with a high degree of participant influence is more effective than a tell‐and‐sell strategy. Using a quasi‐experimental design with a participation, a tell‐and‐sell, and a control condition, a ProMES performance management system was implemented in the field service department of a Dutch supplier of photocopiers. Outcome feedback to individual technicians resulted in an average performance increase in the participation condition that was significantly higher than the increase found in the tell‐and‐sell condition. Satisfaction with the program, and the perceived usefulness of the feedback, were significantly higher in the participation condition. In both experimental conditions, the performance increase was significant compared to the control condition. An explanation for these findings is discussed, as are implications for theory and practice. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
350.
Material flow analysis (MFA) has been applied to assess the environmental impact of human activities on nutrient flows at the commune scale. This paper reports the assessment of human excreta and animal manure as a nutrient source for paddy fields and fishponds in Hoang Tay commune, Ha Nam province, Vietnam. The quality of MFA model was confirmed through modified uncertainty analysis, then was used to originally quantify and visualize the interlinks of livestock with the environmental sanitation and agricultural system in terms of nutrients. Currently, half of the pig manure was collected to the biogas, and the remainders were freely discharged to the commune’s drainage system (25%) or directly reused in the paddy fields (25%). While wastewater in the drainage system was the biggest source of nitrogen (contributed 46%), paddy field was the biggest source of phosphorous (contributed 55%) discharged to the Nhue River, totaling 57 ± 9 ton N and 29 ± 6 ton P, annually. Consequently, mitigation measures for nutrient resource management were proposed, and reducing half of chemical fertilizers applied and reusing all excreta and manure in the paddy fields were the most effective option.  相似文献   
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