38 resultados para mapping the current state


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Introduction. The DRIVER I project drew up a detailed report of European repositories based on data gathered in a survey in which Spain's participation was very low. This created a highly distorted image of the implementation of repositories in Spain. This study aims to analyse the current state of Spanish open-access institutional repositories and to describe their characteristics. Method. The data were gathered through a Web survey. The questionnaire was based on that used by DRIVER I: coverage; technical infrastructure and technical issues; institutional policies; services created; and stimulators and inhibitors for establishing, filling and maintaining their digital institutional repositories. Analysis. Data were tabulated and analysed systematically according responses obtained from the questionnaire and grouped by coverage. Results. Responses were obtained from 38 of the 104 institutions contacted, which had 29 institutional repositories. This represents 78.3% of the Spanish repositories according to the BuscaRepositorios directory. Spanish repositories contained mainly full-text materials (journal articles and doctoral theses) together with metadata. The software most used was DSpace, followed by EPrints. The metadata standard most used was Dublin Core. Spanish repositories offered more usage statistics and fewer author-oriented services than the European average. The priorities for the future development of the repositories are the need for clear policies on access to scientific production based on public funding and the need for quality control indicators. Conclusions.This is the first detailed study of Spanish institutional repositories. The key stimulants for establishing, filling and maintaining were, in order of importance, the increase of visibility and citation, the interest of decision-makers, simplicity of use and search services. On the other hand the main inhibitors identified were the absence of policies, the lack of integration with other national and international systems and the lack of awareness efforts among academia.

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The current state of regional and urban science has been much discussed and a number of studies have speculated on possible future trends in the development of the discipline. However, there has been little empirical analysis of current publication patterns in regional and urban journals. This paper studies the kinds of topics, techniques and data used in articles published in nine top international journals during the 1990s with the aim of identifying current trends in this research field

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In this paper, we study how public and private expenditures in health and education affect economic growth by their influence on people's health, abilities, skills and knowledge. We consider a growth accounting framework in order to test whether welfare expenditures more than offset the efficiency losses caused by distortionary taxation, and whether the effects of public expenditure on economic growth differ from those of private expenditure. Our empirical analysis is based on a panel of 19 OECD countries observed between 1971 and 1998. The results are consistent with the hypothesis that the contribution of welfare expenditures more than compensates for the distortions caused by the tax system; and the estimated positive impact is stronger for health than for education. We also find some evidence that public expenditure influences GDP growth more than private expenditure.

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The current state of regional and urban science has been much discussed and a number of studies have speculated on possible future trends in the development of the discipline. However, there has been little empirical analysis of current publication patterns in regional and urban journals. This paper studies the kinds of topics, techniques and data used in articles published in nine top international journals during the 1990s with the aim of identifying current trends in this research field

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In this paper, we study how public and private expenditures in health and education affect economic growth by their influence on people's health, abilities, skills and knowledge. We consider a growth accounting framework in order to test whether welfare expenditures more than offset the efficiency losses caused by distortionary taxation, and whether the effects of public expenditure on economic growth differ from those of private expenditure. Our empirical analysis is based on a panel of 19 OECD countries observed between 1971 and 1998. The results are consistent with the hypothesis that the contribution of welfare expenditures more than compensates for the distortions caused by the tax system; and the estimated positive impact is stronger for health than for education. We also find some evidence that public expenditure influences GDP growth more than private expenditure.

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Neutron-scattering techniques have been used to study the premartensitic state of a family of Cu-Al-Be alloys, which transform from the bcc phase to an 18R martensitic structure. We find that the phonon modes of the TA2[110] branch have very low energies with anomalous temperature dependence. A slight anomaly at q=2/3 was observed; this anomaly, however, does not change significantly with temperature. No elastic peaks, related to the martensite structure, were found in the premartensitic state of these alloys. The results are compared with measurements, performed under the same instrumental conditions, on two Cu-Al-Ni and a Cu-Zn-Al martensitic alloy.

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The influence of Delta isobar components on the ground-state properties of nuclear systems is investigated for nuclear matter as well as finite nuclei. Many-body wave functions, including isobar configurations and binding energies, are evaluated employing the framework of the coupled-cluster theory. It is demonstrated that the effect of isobar configurations depends in a rather sensitive way on the model used for the baryon-baryon interaction. As examples for realistic baryon-baryon interactions with explicit inclusion of isobar channels we use the local (V28) and nonlocal meson-exchange potentials (Bonn2000) but also a model recently developed by the Salamanca group, which is based on a quark picture. The differences obtained for the nuclear observables are related to the treatment of the interaction, the pi-exchange contributions in particular, at high momentum transfers.

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We study the exact ground state of the two-dimensional random-field Ising model as a function of both the external applied field B and the standard deviation ¿ of the Gaussian random-field distribution. The equilibrium evolution of the magnetization consists in a sequence of discrete jumps. These are very similar to the avalanche behavior found in the out-of-equilibrium version of the same model with local relaxation dynamics. We compare the statistical distributions of magnetization jumps and find that both exhibit power-law behavior for the same value of ¿. The corresponding exponents are compared.

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We deal with the hysteretic behavior of partial cycles in the two¿phase region associated with the martensitic transformation of shape¿memory alloys. We consider the problem from a thermodynamic point of view and adopt a local equilibrium formalism, based on the idea of thermoelastic balance, from which a formal writing follows a state equation for the material in terms of its temperature T, external applied stress ¿, and transformed volume fraction x. To describe the striking memory properties exhibited by partial transformation cycles, state variables (x,¿,T) corresponding to the current state of the system have to be supplemented with variables (x,¿,T) corresponding to points where the transformation control parameter (¿¿ and/or T) had reached a maximum or a minimum in the previous thermodynamic history of the system. We restrict our study to simple partial cycles resulting from a single maximum or minimum of the control parameter. Several common features displayed by such partial cycles and repeatedly observed in experiments lead to a set of analytic restrictions, listed explicitly in the paper, to be verified by the dissipative term of the state equation, responsible for hysteresis. Finally, using calorimetric data of thermally induced partial cycles through the martensitic transformation in a Cu¿Zn¿Al alloy, we have fitted a given functional form of the dissipative term consistent with the analytic restrictions mentioned above.

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We present a very simple but fairly unknown method to obtain exact lower bounds to the ground-state energy of any Hamiltonian that can be partitioned into a sum of sub-Hamiltonians. The technique is applied, in particular, to the two-dimensional spin-1/2 antiferromagnetic Heisenberg model. Reasonably good results are easily obtained and the extension of the method to other systems is straightforward.

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BaFe10.4Co0.8Ti0.8O19 magnetic fine particles exhibit most of the features attributed to glassy behavior, e.g., irreversibility in the hysteresis loops and in the zero-field-cooling and field-cooling curves extends up to very high fields, and aging and magnetic training phenomena occur. However, the multivalley energy structure of the glassy state can be strongly modified by a field-cooling process at a moderate field. Slow relaxation experiments demonstrate that the intrinsic energy barriers of the individual particles dominate the behavior of the system at high cooling fields, while the energy states corresponding to collective glassy behavior play the dominant role at low cooling fields.

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Trust in public institutions and public policies are generally perceived as a precondition for economic recovery in times of recession. Recent empirical evidence tends to find a positive link between decentralization and trust. But our knowledge about whether decentralization – through increased trust – improves the perception of the delivery and effectiveness of public policies is still limited. In this paper we estimate the impact of fiscal and political decentralization on the perception of the state of the education system and of health services, by using the 2002, 2004, 2006 and 2008 waves of the European social survey. The analysis of the views of 160,000 individuals in 31 European countries indicates that while the effect of fiscal decentralization on the perception of the state of the health and education system is limited, political decentralization clearly affects citizen’s satisfaction with education and health delivery. The influence of political decentralization, however, is highly contingent on whether we consider the capacity of the local or regional government to exercise authority over its citizens (self-rule) or to influence policy at the national level (shared-rule). Keywords: Education, health, satisfaction, fiscal and political decentralization, Europe. JEL codes: H11, H77

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Background: Methotrexate is a chemotherapeutic agent used to treat a variety of cancers. However, the occurrence of resistance limits its effectiveness. Cytochrome c in its reduced state is less capable of triggering the apoptotic cascade. Thus, we set up to study the relationship among redox state of cytochrome c, apoptosis and the development of resistance to methotrexate in MCF7 human breast cancer cells. Results: Cell incubation with cytochrome c-reducing agents, such as tetramethylphenylenediamine, ascorbate or reduced glutathione, decreased the mortality and apoptosis triggered by methotrexate. Conversely, depletion of glutathione increased the apoptotic action of methotrexate, showing an involvement of cytochrome c redox state in methotrexateinduced apoptosis. Methotrexate-resistant MCF7 cells showed increased levels of endogenous reduced glutathione and a higher capability to reduce exogenous cytochrome c. Using functional genomics we detected the overexpression of GSTM1 and GSTM4 in methotrexate-resistant MCF7 breast cancer cells, and determined that methotrexate was susceptible of glutathionylation by GSTs. The inhibition of these GSTM isoforms caused an increase in methotrexate cytotoxicity in sensitive and resistant cells. Conclusions: We conclude that overexpression of specific GSTMs, GSTM1 and GSTM4, together with increased endogenous reduced glutathione levels help to maintain a more reduced state of cytochrome c which, in turn, would decrease apoptosis, thus contributing to methotrexate resistance in human MCF7 breast cancer cells.