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81.
•  We analyze the impact of structural reform on firm exports. We argue that structural reform generates new opportunities and reduces transaction costs, inducing firms to improve their efficiency and competitiveness to international levels, therefore, helping them to export. However, we propose that not all companies benefit equally, because firms differ in how structural reform affects their competitiveness. We argue that subsidiaries of foreign firms are the main beneficiaries of structural reform, followed by domestic private firms, and finally by domestic state-owned firms.
•  We test these arguments on a sample of the largest companies in Latin America for the period 1990–2005. We find that structural reform induces firms to export. Furthermore, it has the highest positive impact on the exports of subsidiaries of foreign firms, followed by those of domestic private firms. Surprisingly, we find that structural reform has a negative impact on the exports of domestic state-owned firms.
•  The paper contributes to a better understanding of how changes in institutions affect firm behavior by explaining the mechanisms that link structural reform to firm exports and how these vary across firms. Moreover, by indicating that not only foreign but also domestic private firms benefit from structural reform, it counters the arguments of detractors of globalization who claim that foreign firms are the sole beneficiaries of structural reform. The paper also highlights the need to discuss who benefits from structural reform rather than whether structural reform is beneficial or detrimental.
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International open government initiatives are releasing an increasing volume of raw government datasets directly to citizens via the Web. The transparency resulting from these releases not only creates new application opportunities but also imposes new burdens inherent to large-scale distributed data integration, collaborative data manipulation and transparent data consumption. The Tetherless World Constellation (TWC) at Rensselaer Polytechnic Institute (RPI) has developed the Semantic Web-based TWC LOGD portal to support the deployment of linked open government data (LOGD). The portal is both an open source infrastructure supporting linked open government data production and consumption and a vibrant community portal that educates and serves the growing international open government community of developers, data curators and end users. This paper motivates and introduces the TWC LOGD Portal and highlights innovative aspects and lessons learned.  相似文献   
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Orai1, the first identified member of the Orai protein family, is ubiquitously expressed in the animal kingdom. Orai1 was initially characterized as the channel responsible for the store-operated calcium entry (SOCE), a major mechanism that allows cytosolic calcium concentration increments upon receptor-mediated IP3 generation, which results in intracellular Ca2+ store depletion. Furthermore, current evidence supports that abnormal Orai1 expression or function underlies several disorders. Orai1 is, together with STIM1, the key element of SOCE, conducting the Ca2+ release-activated Ca2+ (CRAC) current and, in association with TRPC1, the store-operated Ca2+ (SOC) current. Additionally, Orai1 is involved in non-capacitative pathways, as the arachidonate-regulated or LTC4-regulated Ca2+ channel (ARC/LRC), store-independent Ca2+ influx activated by the secretory pathway Ca2+-ATPase (SPCA2) and the small conductance Ca2+-activated K+ channel 3 (SK3). Furthermore, Orai1 possesses two variants, Orai1α and Orai1β, the latter lacking 63 amino acids in the N-terminus as compared to the full-length Orai1α form, which confers distinct features to each variant. Here, we review the current knowledge about the differences between Orai1α and Orai1β, the implications of the Ca2+ signals triggered by each variant, and their downstream modulatory effect within the cell.  相似文献   
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The receiver behavior of parabolic troughs in direct steam generation (DSG) has been studied under different experimental conditions. When cool water was fed into steel receiver pipes (Ø = 2.54 cm), the pipes deflected. This bend advanced like a wave from the inlet to the outlet end, having a deflection of about 6.5 cm at the center of each section (2.90 m long) in the parabolic trough module (14.5 m long and 2.5 m aperture). This phenomenon was due to a temperature difference of about 50°C in the circumferential direction. When the steel receiver pipe was changed to a copper receiver, the circumferential temperature difference was practically eliminated and no appreciable bending of the pipe was observed, hence DSG was obtained without these problems.  相似文献   
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The mutation of the p53 gene is a common phenomenon in numerous human tumors, leading to the accumulation of nonfunctioning p53 protein in the cell nucleus, which can be detected by immunohistochemistry. In breast cancer, it has been suggested that the overexpression of p53 protein in the nucleus is an indicator of poor prognosis, which must be borne in mind in selecting coadjuvant treatment for each patient. This study is an immunohistochemical analysis of p53 expression in 153 cases of mammary carcinoma, correlating it with histological grade, axillary node status, hormone receptors, cell-proliferation fraction and expression of the c-erbB-2 oncoprotein. Of all the breast-cancer tissue analyzed, 43.79% was positive for p53. The overexpression of this protein bears a direct statistically significant relationship to histological grade, cell-proliferation fraction and c-erbB-2, and an inverse relationship to estrogen and progesterone receptors. No statistically significant relationship was found with axillary node status. The expression of p53 in poorly differentiated tumors-commonly receptor negative and with a high proliferation fraction-may indicate greater tumor aggressiveness and a high risk of relapse.  相似文献   
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INTRODUCTION: Radiofrequency ablation has been extensively used in adults to treat supraventricular and ventricular tachycardia. In children and adolescents few data are available on its safety and efficacy. METHODS: 28 patients (mean age 12.8) with symptomatic tachyarrhythmias underwent catheter ablation; 21 children had atrioventricular accessory pathways (11 right connections, 9 lef connections and one midseptal pathway), 3 had intranodal tachycardia, 2 had ventricular tachycardia and 2 had atrial tachycardia. Only four patients had associated structural anomalies. RESULTS: Success rate was 71.4% (20 patients). The success per cents in each group were: in intranodal tachycardias 100%; we failed in the two patients with ventricular tachycardias; in accessory pathways 76.1% and 50% in atrial tachycardia. There were no recurrences of arrhythmia in a mean chase period of 24 months (12-46). Major complications were only observed in one patient who developed a Wallenberg syndrome after ablation. CONCLUSIONS: Radiofrequency catheter ablation appears to be a safe and effective method to treat arrhythmias in children and adolescents, which in most cases can supersede surgery. Alow incidence of complications is reported, although long term damage on endocardial structures remains yet to be determined.  相似文献   
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