7,218 research outputs found

    A Comparative Study of EU and US Trade Policies for Developing Countries: The Case of Agri-Food Products

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    Trade relations between developed and developing countries are one of the hot topics of the ongoing World Trade Organization (WTO) negotiations. The conclusion of the Cotonou Agreement between EU and African, Caribbean and Pacific countries, the introduction of the EU’s Everything But Arms initiative for the least developed countries and the United States’ African Growth and Opportunity Act for 39 African Countries, represents tangible incentives for many developing countries to continue their efforts to open their economies and build free markets. This paper analyzes the trade creating effects of EU and US trade policies as total effect, for agri-food products of developing countries in a gravity model framework. Data refer to a 10 year period: 1996-2005. The findings show larger trade creating effects of EU trade policies, especially for upper-middle income countries. Variation in trade creation, across the years, is not statistically significant, except for the low-income countries.Gross Trade Creation, Agricultural Trade Policy, Developed and Developing Countries, International Relations/Trade,

    Operation Frames and Clubs in Kidney Exchange

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    A kidney exchange is a centrally-administered barter market where patients swap their willing yet incompatible donors. Modern kidney exchanges use 2-cycles, 3-cycles, and chains initiated by non-directed donors (altruists who are willing to give a kidney to anyone) as the means for swapping. We propose significant generalizations to kidney exchange. We allow more than one donor to donate in exchange for their desired patient receiving a kidney. We also allow for the possibility of a donor willing to donate if any of a number of patients receive kidneys. Furthermore, we combine these notions and generalize them. The generalization is to exchange among organ clubs, where a club is willing to donate organs outside the club if and only if the club receives organs from outside the club according to given specifications. We prove that unlike in the standard model, the uncapped clearing problem is NP-complete. We also present the notion of operation frames that can be used to sequence the operations across batches, and present integer programming formulations for the market clearing problems for these new types of organ exchanges. Experiments show that in the single-donation setting, operation frames improve planning by 34%--51%. Allowing up to two donors to donate in exchange for one kidney donated to their designated patient yields a further increase in social welfare.Comment: Published at IJCAI-1

    A Systematic Approach for Evaluating Satellite Communications Systems

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    The aerospace environment imposes straight opera- tive conditions so every electronic system usually needs to be validated for these. The same way, communica- tion systems need to be evaluated before their intro- duction in aerospace applications. In the paper we present a new methodology for the evaluation of com- munication systems in space applications. The meth- odology aims, by abstraction, at identifying all the critical aspects for the evaluation and at defining a standard and reusable framework in order to be appli- cable to any Communication Systems. The methodol- ogy has been applied for the evaluation of three Data Bus for satellite communications: 1553, 1-Wire and Profibus DP RS 485 based systems have been analyzed and evaluate

    Dynamical symmetries and crossovers in a three-spin system with collective dissipation

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    We consider the non-equilibrium dynamics of a simple system consisting of interacting spin-1/21/2 particles subjected to a collective damping. The model is close to situations that can be engineered in hybrid electro/opto-mechanical settings. Making use of large-deviation theory, we find a Gallavotti-Cohen symmetry in the dynamics of the system as well as evidence for the coexistence of two dynamical phases with different activity levels. We show that additional damping processes smoothen out this behavior. Our analytical results are backed up by Monte Carlo simulations that reveal the nature of the trajectories contributing to the different dynamical phases.Comment: 6 pages, 5 figure

    Evaluating the expression of urokinase and tissue leukocyte being in benign and malignant breast disease

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    Introduction: Our objectives is to show that the expression of uPA leukocyte could be considered, in the future, as a marker of the expression of uPA in the malignant tissue and therefore a potential indicator of prognosis. Methods: We examined the expression of uPa in leukocytes and tissues of three groups of women: with breast cancer; with benign breast lesion and healthy women (control group). We used RT Real Time PCR assay. The expression of urokinase is significantly higher in malignant breast lumps compared to benign lesions. However, in women with carcinoma of the breast, malignant tissue expresses higher amounts of uPA than the healthy counterpart. There are no statistically significant differences in the expression of uPA, between tissues taken from women with benign lesions. The lymphocytes taken from healthy volunteers show a level of expression of uPA significantly lower than the other tested samples Lymphocytes extracted from cancer patients express higher amounts of uPA compared to lymphocytes belonging to women with benign breast lesions. The expression of uPA was compared with the clinical and biological parameters commonly used in clinical practice for the definition of the prognosis. The only exception found, concerns those tumors characterized by the simultaneous negativity for estrogen receptors, progesterone and HER2 (state of triple negative), in which the expression of uPA is very high. Results and conclusions: Our data show that uPA expressed by leukocytes of each individual patient is the mirror image of the one expressed by malignant nodular uPA.Introduction: Our objectives is to show that the expression of uPA leukocyte could be considered, in the future, as a marker of the expression of uPA in the malignant tissue and therefore a potential indicator of prognosis. Methods: We examined the expression of uPa in leukocytes and tissues of three groups of women: with breast cancer; with benign breast lesion and healthy women (control group). We used RT Real Time PCR assay. The expression of urokinase is significantly higher in malignant breast lumps compared to benign lesions. However, in women with carcinoma of the breast, malignant tissue expresses higher amounts of uPA than the healthy counterpart. There are no statistically significant differences in the expression of uPA, between tissues taken from women with benign lesions. The lymphocytes taken from healthy volunteers show a level of expression of uPA significantly lower than the other tested samples Lymphocytes extracted from cancer patients express higher amounts of uPA compared to lymphocytes belonging to women with benign breast lesions. The expression of uPA was compared with the clinical and biological parameters commonly used in clinical practice for the definition of the prognosis. The only exception found, concerns those tumors characterized by the simultaneous negativity for estrogen receptors, progesterone and HER2 (state of triple negative), in which the expression of uPA is very high. Results and conclusions: Our data show that uPA expressed by leukocytes of each individual patient is the mirror image of the one expressed by malignant nodular uPA

    Efficient Monetary Allocations and the Illiquidity of Bonds

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    We construct a monetary economy with heterogeneity in discounting and consumption risk. Agents can insure against this risk with money and nominal government bonds, but all trades must be monetary. We demonstrate that a deflationary policy a la Friedman cannot sustain the constrained-efficient allocation as no-arbitrage imposes too stringent a bound on the return money can pay. The constrained-efficient allocation can be sustained when bonds have positive yields and, under certain conditions, only if they are illiquid. Illiquidity, meaning that bonds cannot be transformed into consumption as easily as cash, is necessary to eliminate arbitrage opportunities due to disparities in shadow interest rates
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