995 resultados para Allocation factor
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Against the background of the current discussion about the EU’s common agricultural policy (CAP) after 2013, the question of the impact of government support on land prices is crucially important. Validation of the CAP’s success also hinges on a proper assessment of a choice of policy instruments. This study therefore has the objective of investigating on a theoretical basis the effects of different government support measures on land rental prices and land allocation. The different measures under consideration are the price support, area payments and decoupled single farm payments (SFPs) of the CAP. Our approach evaluates the potential impact of each measure based on a Ricardian land rent model with heterogeneous land quality and multiple land uses. We start with a simple model of one output and two inputs, where a Cobb-Douglas production technology is assumed between the two factors of land and non-land inputs. In a second step, an outside option is introduced. This outside option, as opposed to land use of the Ricardian type, is independent of land quality. The results show that area payments and SFPs become fully capitalised into land rents, whereas in a price support scheme the capitalisation depends on per-acreage productivity. Moreover, in a price support scheme and a historical model, the capitalisation is positively influenced by land quality. Both area payments and price supports influence land allocation across different uses compared with no subsidies, where the shift tends to be larger in an area payment scheme than in a price support scheme. By contrast, SFPs do not influence land allocation.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This paper presents a theoretical model for the analysis of decisions regarding farm household labour allocation. The agricultural household model is selected as the most appropriate theoretical framework; a model based on the assumption that households behave to maximise utility, which is a function of consumption and leisure, and is subject to time and budget constraints. The model can be used to describe the role of government subsidies in farm household labour allocation decisions; in particular the impact of decoupled subsidies on labour allocation can be examined. Decoupled subsidies are a labour-free payment and as such represent an increase in labour-free income or wealth. An increase in wealth allows farm households to work less while maintaining consumption. On the other hand, decoupled subsidies represent a decline in the return to farm labour and may lead to a substitution effect, i.e., farmers may choose to substitute non-farm work for farm work. The theoretical framework proposed in this paper allows for the examination of these two conflicting effects.
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Six alternative structural models of individualism-collectivism are reviewed and empirically compared in a confirmatory factor analysis of questionnaire data from an Australian student sample (N=340). Central to the debate about the structure of this broad social attitude are the issues of (I) polarity (are individualism and collectivism bipolar opposites, or orthogonal factors?) and (2) dimensionality (are individualism and collectivism themselves higher-order constructs subsuming several more specific factors and, if so, what are they?). The data from this Australian sample support a model that represents individualism and collectivism as a higher-order bipolar factor hierarchically subsuming several bipolar reference-group-specific individualisms and collectivisms. Copyright (C) 2001 John Wiley & Sons, Ltd.
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OBJECTIVE To analyze whether gender influence survival results of kidney transplant grafts and patients.METHODS Systematic review with meta-analysis of cohort studies available on Medline (PubMed), LILACS, CENTRAL, and Embase databases, including manual searching and in the grey literature. The selection of studies and the collection of data were conducted twice by independent reviewers, and disagreements were settled by a third reviewer. Graft and patient survival rates were evaluated as effectiveness measurements. Meta-analysis was conducted with the Review Manager® 5.2 software, through the application of a random effects model. Recipient, donor, and donor-recipient gender comparisons were evaluated.RESULTS : Twenty-nine studies involving 765,753 patients were included. Regarding graft survival, those from male donors were observed to have longer survival rates as compared to the ones from female donors, only regarding a 10-year follow-up period. Comparison between recipient genders was not found to have significant differences on any evaluated follow-up periods. In the evaluation between donor-recipient genders, male donor-male recipient transplants were favored in a statistically significant way. No statistically significant differences were observed in regards to patient survival for gender comparisons in all follow-up periods evaluated.CONCLUSIONS The quantitative analysis of the studies suggests that donor or recipient genders, when evaluated isolatedly, do not influence patient or graft survival rates. However, the combination between donor-recipient genders may be a determining factor for graft survival.
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica
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QUESTION UNDER STUDY: To assess which high-risk acute coronary syndrome (ACS) patient characteristics played a role in prioritising access to intensive care unit (ICU), and whether introducing clinical practice guidelines (CPG) explicitly stating ICU admission criteria altered this practice. PATIENTS AND METHODS: All consecutive patients with ACS admitted to our medical emergency centre over 3 months before and after CPG implementation were prospectively assessed. The impact of demographic and clinical characteristics (age, gender, cardiovascular risk factors, and clinical parameters upon admission) on ICU hospitalisation of high-risk patients (defined as retrosternal pain of prolonged duration with ECG changes and/or positive troponin blood level) was studied by logistic regression. RESULTS: Before and after CPG implementation, 328 and 364 patients, respectively, were assessed for suspicion of ACS. Before CPG implementation, 36 of the 81 high-risk patients (44.4%) were admitted to ICU. After CPG implementation, 35 of the 90 high-risk patients (38.9%) were admitted to ICU. Male patients were more frequently admitted to ICU before CPG implementation (OR=7.45, 95% CI 2.10-26.44), but not after (OR=0.73, 95% CI 0.20-2.66). Age played a significant role in both periods (OR=1.57, 95% CI 1.24-1.99), both young and advanced ages significantly reducing ICU admission, but to a lesser extent after CPG implementation. CONCLUSION: Prioritisation of access to ICU for high-risk ACS patients was age-dependent, but focused on the cardiovascular risk factor profile. CPG implementation explicitly stating ICU admission criteria decreased discrimination against women, but other factors are likely to play a role in bed allocation.
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We consider the problem of provisioon and cost-sharing of multiple public goods. the efficient equal factor equivalent allocation rule makes every agent indifferent between what he receives and the opportunity of choosing the bundle of public goods subject to the constraint of paying r times its cost, where r is set as low as possible.
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Practical applications of portfolio optimisation tend to proceed on a “top down” basis where funds are allocated first at asset class level (between, say, bonds, cash, equities and real estate) and then, progressively, at sub-class level (within property to sectors, office, retail, industrial for example). While there are organisational benefits from such an approach, it can potentially lead to sub-optimal allocations when compared to a “global” or “side-by-side” optimisation. This will occur where there are correlations between sub-classes across the asset divide that are masked in aggregation – between, for instance, City offices and the performance of financial services stocks. This paper explores such sub-class linkages using UK monthly stock and property data. Exploratory analysis using clustering procedures and factor analysis suggests that property performance and equity performance are distinctive: there is little persuasive evidence of contemporaneous or lagged sub-class linkages. Formal tests of the equivalence of optimised portfolios using top-down and global approaches failed to demonstrate significant differences, whether or not allocations were constrained. While the results may be a function of measurement of market returns, it is those returns that are used to assess fund performance. Accordingly, the treatment of real estate as a distinct asset class with diversification potential seems justified.
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We study a two-way relay network (TWRN), where distributed space-time codes are constructed across multiple relay terminals in an amplify-and-forward mode. Each relay transmits a scaled linear combination of its received symbols and their conjugates,with the scaling factor chosen based on automatic gain control. We consider equal power allocation (EPA) across the relays, as well as the optimal power allocation (OPA) strategy given access to instantaneous channel state information (CSI). For EPA, we derive an upper bound on the pairwise-error-probability (PEP), from which we prove that full diversity is achieved in TWRNs. This result is in contrast to one-way relay networks, in which case a maximum diversity order of only unity can be obtained. When instantaneous CSI is available at the relays, we show that the OPA which minimizes the conditional PEP of the worse link can be cast as a generalized linear fractional program, which can be solved efficiently using the Dinkelback-type procedure.We also prove that, if the sum-power of the relay terminals is constrained, then the OPA will activate at most two relays.
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Background: Several methods have been utilized to prevent pericardial and retrosternal adhesions, but none of them evaluated the mesothelial regenerative hypothesis. There are evidences that the mesothelial trauma reduces pericardial fibrinolytic capability and induces an adhesion process. Keratinocyte growth factor (KGF) has proven to improve mesothelial cells proliferation. This study investigated the influence of keratinocyte growth factor in reducing post-surgical adhesions. Methods: Twelve pigs were operated and an adhesion protocol was employed. Following a stratified randomization, the animals received a topical application of KGF or saline. At 8 weeks, intrapericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histological sections were stained with sirius red and morphometric analyses were assessed with a computer-assisted image analysis system. Results: The severity score was lower in the KGF group than in the control group (11.5 vs 17, p = 0.005). The dissection time was lower in the KGF group (9.2 +/- 1.4 min vs 33.9 +/- 9.2 min, p = 0.004) and presented a significant correlation with the severity score (r = 0.83, p = 0.001). A significantly less sharp dissection was also required in the KGF group. Also, adhesion area and adhesion collagen were significantly tower in the KGF group than in the control group. Conclusion: The simulation of pericardial cells with KGF reduced the intensity of postoperative adhesions and facilitated the re-operation. This study suggests that the mesothelial regeneration is the new horizon in anti-adhesion therapies. (C) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.
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Treatment allocation by epidermal growth factor receptor mutation status is a new standard in patients with metastatic nonesmall-cell lung cancer. Yet, relatively few modern chemotherapy trials were conducted in patients characterized by epidermal growth factor receptor wild type. We describe the results of a multicenter phase II trial, testing in parallel 2 novel combination therapies, predefined molecular markers, and tumor rebiopsy at progression. Objective: The goal was to demonstrate that tailored therapy, according to tumor histology and epidermal growth factor receptor (EGFR) mutation status, and the introduction of novel drug combinations in the treatment of advanced nonesmall-cell lung cancer are promising for further investigation. Methods: We conducted a multicenter phase II trial with mandatory EGFR testing and 2 strata. Patients with EGFR wild type received 4 cycles of bevacizumab, pemetrexed, and cisplatin, followed by maintenance with bevacizumab and pemetrexed until progression. Patients with EGFR mutations received bevacizumab and erlotinib until progression. Patients had computed tomography scans every 6 weeks and repeat biopsy at progression. The primary end point was progression-free survival (PFS) ≥ 35% at 6 months in stratum EGFR wild type; 77 patients were required to reach a power of 90% with an alpha of 5%. Secondary end points were median PFS, overall survival, best overall response rate (ORR), and tolerability. Further biomarkers and biopsy at progression were also evaluated. Results: A total of 77 evaluable patients with EGFR wild type received an average of 9 cycles (range, 1-25). PFS at 6 months was 45.5%, median PFS was 6.9 months, overall survival was 12.1 months, and ORR was 62%. Kirsten rat sarcoma oncogene mutations and circulating vascular endothelial growth factor negatively correlated with survival, but thymidylate synthase expression did not. A total of 20 patients with EGFR mutations received an average of 16.
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Drawing on a unique, farm-level panel dataset with 37,409 observations and employing a matching estimator, this paper analyses how farm access to credit affects farm input allocation and farm efficiency in the Central and Eastern European transition countries. We find that farms are asymmetrically credit constrained with respect to inputs. Farm use of variable inputs and capital investment increases up to 2.3% and 29%, respectively, per €1,000 of additional credit. Our estimates also suggest that farm access to credit increases total factor productivity up to 1.9% per €1,000 of additional credit, indicating that an improvement in access to credit results in an adjustment in the relative input intensities on farms. This finding is further supported by a negative effect of better access to credit on labour, suggesting that these two are substitutes. Interestingly, farms are found not to be credit constrained with respect to land.
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This paper provides a synthesis of the empirical literature on the key issues in agricultural and rural labour markets since 1960s, drawing mainly upon studies from the United States and the European Union, but also including relevant material from developing countries. The contribution of this meta-analysis lies in its unique structure as it covers the main research questions which have been addressed in the literature and includes the most cited papers from the American Journal of Agricultural Economics, Journal of Agricultural Economics, European Review of Agricultural Economics, Agricultural Economics as well as other reports and EU funded projects. Each research question is accompanied by tabular summaries which classify the individual studies according to the methodology and the variables employed. The heterogeneous conditions across countries, the different research questions and methodologies, and the type of data employed, have sometimes led to conflicting results. Nonetheless, by comparing the results it is possible to assess the significance and the direction of the determinants of rural labour allocation and its adjustments, and thus contribute to a better understanding on the functioning of rural labour markets. Lastly, by recognising the importance of the institutional framework, the paper provides useful policy insights.
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The paper criticises the neo-classical assumptions of perfect factor markets and of complete information, which constitute central elements in labour market theory. Based on literature review and on economic reports from transition economies, as well as developing countries and more advanced economies, this deliverable focuses on the structural impediments and imperfections which often characterise rural labour markets and which may prevent an efficient allocation of labour. According to empirical studies, transactions costs and rigidities hinder the well-functioning of labour markets and constrain labour adjustments. The paper attempts to classify the various limitations of rural labour markets from both supply and demand side, although the distinction is not always clear-cut as some problems occur on both sides. The identification of these issues is extremely important as it allows us to highlight the inefficiencies and the failures in labour markets and to understand their impact on labour allocation. In this context, market intervention is desirable and the paper provides particular support for rural development policies such as investments in human capital. Lastly, labour institutions can play a key role in promoting the well functioning of labour markets, thus it is fundamental that they are well in place.