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Elena D. Concepción Martin K. Obrist Marco Moretti Florian Altermatt Bruno Baur Michael P. Nobis 《Urban Ecosystems》2016,19(1):225-242
Urban growth is a major factor of global environmental change and has important impacts on biodiversity, such as changes in species composition and biotic homogenization. Most previous studies have focused on effects of urban area as a general measure of urbanization, and on few or single taxa. Here, we analyzed the impacts of the different components of urban sprawl (i.e., scattered and widespread urban growth) on species richness of a variety of taxonomic groups covering mosses, vascular plants, gastropods, butterflies, and birds at the habitat and landscape scales. Besides urban area, we considered the average age, imperviousness, and dispersion degree of urban area, along with human population density, to disentangle the effects of the different components of urban sprawl on biodiversity. The study was carried out in the Swiss Plateau that has undergone substantial urban sprawl in recent decades.Vascular plants and birds showed the strongest responses to urban sprawl, especially at the landscape scale, with non-native and ruderal plants proliferating and common generalist birds increasing at the expense of specialist birds as urban sprawl grew. Overall, urban area had the greatest contribution on such impacts, but additional effects of urban dispersion (i.e., increase of non-native plants) and human population density (i.e., increases of ruderal plants and common generalist birds) were found. Our findings support the hypothesis that negative impacts of urban sprawl on biodiversity can be reduced by compacting urban growth while still avoiding the formation of very densely populated areas. 相似文献
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Sociological inquiry into the natural sciences has shown that they are contingent, social constructions. However, Science Studies research has been obstructed by epistemological conflicts about the nature of science and theoretical perspectives upon studying it. Bourdieu's sociology of science is under‐utilized in this field, as he addresses these obstructions and offers a way forward. Bourdieu argues that researchers have failed to distinguish between sociological and philosophical approaches in social science, thus committing the ‘scholastic fallacy’. In conjunction with this fallacy, the logic of the Science Studies field produces a tendency towards disciplinary confusion, philosophical radicalization, and crisis. These patterns were expressed in the ‘science wars’. The field has followed a philosophical path rather than a sociological one, and its progress has been obstructed. While some of Bourdieu's philosophical arguments remain problematic, his reflexive sociology allows us to differentiate philosophical from sociological approaches, providing an alternative direction for Science Studies. 相似文献
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Statistical Methods & Applications - In this paper we propose to study the dynamics of financial contagion between the credit default swap (CDS) and the sovereign bond markets through effective... 相似文献
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Viña J Borrás C Gambini J Sastre J Pallardó FV 《Science of aging knowledge environment : SAGE KE》2005,2005(23):pe17
Females live longer than males in many species, including humans. We have traced a possible explanation for this phenomenon to the beneficial action of estrogens, which bind to estrogen receptors and increase the expression of longevity-associated genes, including those encoding the antioxidant enzymes superoxide dismutase and glutathione peroxidase. As a result, mitochondria from females produce fewer reactive oxygen species than those from males. Administering estrogens has serious drawbacks, however--they are feminizing (and thus cannot be administered to males) and may increase the incidence of serious diseases such as uterine cancer in postmenopausal women. Phytoestrogens, which are present in soy or wine, may have some of the favorable effects of estrogens without their undesirable effects. Study of gender differences in longevity may help us to understand the basic processes of aging and to devise practical strategies to increase the longevity of both females and males. 相似文献
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Concepción Carrasco Carpio Carlos García-Serrano Virginia Hernanz 《International migration (Geneva, Switzerland)》2020,58(3):235-257
This article aims to examine in depth the work trajectories of individuals over time, in order to provide a wider perspective of the employment history of immigrants compared to native people, by gender and for more than one decade (2005–2017) in Spain. We use microdata (cohort and multivariate analysis) from the Labour Force Survey and carry out a comparison for three groups: the Spanish born in Spain, the Spanish born abroad, and the non-Spanish born abroad. The results confirm that the non-Spanish born-abroad group is characterized by the existence of segmented assimilation. All foreigners suffered a loss in their work trajectories, since their employment rate in 2017 has as yet neither reached the level of the last years of the previous economic expansion nor the level of the previous cohorts at the same age. 相似文献
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Anikó Bíró 《Journal of population economics》2013,26(4):1379-1408
I estimate the effect of shocks to subjective mortality hazards on consumption expenditures of retired individuals using the Survey of Health, Ageing and Retirement in Europe. I measure mortality expectations with survey responses on survival probabilities. To create plausibly exogenous variation in mortality hazard, I use the death of a sibling as an instrument. My results show that survey responses contain economically relevant information about longevity expectations and confirm the predictions of life-cycle theories about the effect of these expectations on intertemporal choice. 相似文献
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Projecting Long-Term Care Expenditure in Four European Union Member States: The Influence of Demographic Scenarios 总被引:1,自引:0,他引:1
Joan Costa-Font Raphael Wittenberg Concepció Patxot Adelina Comas-Herrera Cristiano Gori Alessandra di Maio Linda Pickard Alessandro Pozzi Heinz Rothgang 《Social indicators research》2008,86(2):303-321
This study examines the sensitivity of future long-term care demand and expenditure estimates to official demographic projections
in four selected European countries: Germany, Spain, Italy and the United Kingdom. It uses standardised methodology in the
form of a macro-simulation exercise and finds evidence for significant differences in assumptions about demographic change
and its effect on the demand for long-term care, and on relative and absolute long-term care expenditure. It concludes that
mortality-rate assumptions can have a considerable influence on welfare policy planning. Relative dispersion between country-specific
and Eurostat official estimates was found to be higher for the United Kingdom and Germany than for Italy and Spain, suggesting
that demographic projections had a greater influence in those countries.
相似文献
Joan Costa-FontEmail: |
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María Concepción Pérez-Cárceles Juan Cándido Gómez-Gallego Juan Gómez-García 《Journal of applied statistics》2016,43(16):3030-3041
The aim of the paper is to demonstrate the appropriateness of an a priori analysis to determine the distributional assumption of the inefficiency term in a stochastic frontier model. To this end, theoretical distributions of estimated inefficiency were obtained when the inefficiency term is assumed to be distributed as a half normal and an exponential in a cost frontier model. Comparisons of such theoretical distributions with the respective cost inefficiency estimators using the goodness of fit test allow selecting the most appropriate distributional assumption. The application on three data sets of Spanish banking system in 2009 demonstrated the relevance of the research question. First, the results of estimated cost inefficiency with a half normal assumption are larger than with an exponential distribution significantly. Besides, half normal assumption was rejected and exponential was not rejected as the most appropriate distribution of inefficiency term in Spanish banking data set. However, the adjustment of saving banks data had been better with the former distribution than the latter. In the case of banks, any distribution results appropriate. To sum up, this work demonstrate that the distributional assumption on inefficiency term in Stochastic Frontier Approach must be established in a justified way, as it can significantly bias the results of estimated inefficiency and therefore, influences improving policies and strategies in the Spanish banking sector. 相似文献