981 resultados para Optimum Financial Activity


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One of the main problems relief teams face after a natural or man-made disaster is how to plan rural road repair work tasks to take maximum advantage of the limited available financial and human resources. Previous research focused on speeding up repair work or on selecting the location of health centers to minimize transport times for injured citizens. In spite of the good results, this research does not take into account another key factor: survivor accessibility to resources. In this paper we account for the accessibility issue, that is, we maximize the number of survivors that reach the nearest regional center (cities where economic and social activity is concentrated) in a minimum time by planning which rural roads should be repaired given the available financial and human resources. This is a combinatorial problem since the number of connections between cities and regional centers grows exponentially with the problem size, and exact methods are no good for achieving an optimum solution. In order to solve the problem we propose using an Ant Colony System adaptation, which is based on ants? foraging behavior. Ants stochastically build minimal paths to regional centers and decide if damaged roads are repaired on the basis of pheromone levels, accessibility heuristic information and the available budget. The proposed algorithm is illustrated by means of an example regarding the 2010 Haiti earthquake, and its performance is compared with another metaheuristic, GRASP.

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Acknowledgment I would like to gratefully acknowledge the government of Saudi Arabia for the scholarship and financial support.

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Hexokinase (HXK; EC 2.7.1.1) regulates carbohydrate entry into glycolysis and is known to be a sensor for sugar-responsive gene expression. The effect of abiotic stresses on HXK activity was determined in seedlings of the flood-tolerant plant Echinochloa phyllopogon (Stev.) Koss and the flood-intolerant plant Echinochloa crus-pavonis (H.B.K.) Schult grown aerobically for 5 d before being subjected to anaerobic, chilling, heat, or salt stress. HXK activity was stimulated in shoots of E. phyllopogon only by anaerobic stress. HXK activity was only transiently elevated in E. crus-pavonis shoots during anaerobiosis. In roots of both species, anoxia and chilling stimulated HXK activity. Thus, HXK is not a general stress protein but is specifically induced by anoxia and chilling in E. phyllopogon and E. crus-pavonis. In both species HXK exhibited an optimum pH between 8.5 and 9.0, but the range was extended to pH 7.0 in air-grown E. phyllopogon to 6.5 in N2-grown E. phyllopogon. At physiologically relevant pHs (6.8 and 7.3, N2 and O2 conditions, respectively), N2-grown seedlings retained greater HXK activity at the lower pH. The pH response suggests that in N2-grown seedlings HXK can function in a more acidic environment and that a specific isozyme may be important for regulating glycolytic activity during anaerobic metabolism in E. phyllopogon.

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Protein extracted from root and leaf tissue of the dicotyledonous plants pea (Pisum sativum) and broad bean (Vicia faba) and the monocotyledonous plants wheat (Triticum aestivum) and barley (Hordeum vulgare) were shown to catalyze the incorporation of biotin-labeled cadaverine into microtiter-plate-bound N′,N′-dimethylcasein and the cross-linking of biotin-labeled casein to microtiter-plate-bound casein in a Ca2+-dependent manner. The cross-linking of biotinylated casein and the incorporation of biotin-labeled cadaverine into N′,N′-dimethylcasein were time-dependent reactions with a pH optimum of 7.9. Transglutaminase activity was shown to increase over a 2-week growth period in both the roots and leaves of pea. The product of transglutaminase's protein-cross-linking activity, ε-(γ-glutamyl)-lysine isodipeptide, was detected in root and shoot protein from pea, broad bean, wheat, and barley by cation-exchange chromatography. The presence of the isodipeptide was confirmed by reversed-phase chromatography. Hydrolysis of the isodipeptide after cation-exchange chromatography confirmed the presence of glutamate and lysine.

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Corn (Zea mays L.) root adaptation to pH 3.5 in comparison with pH 6.0 (control) was investigated in long-term nutrient solution experiments. When pH was gradually reduced, comparable root growth was observed irrespective of whether the pH was 3.5 or 6.0. After low-pH adaptation, H+ release of corn roots in vivo at pH 5.6 was about 3 times higher than that of control. Plasmalemma of corn roots was isolated for investigation in vitro. At optimum assay pH, in comparison with control, the following increases of the various parameters were caused by low-pH treatment: (a) hydrolytic ATPase activity, (b) maximum initial velocity and Michaelis constant (c) activation energy of H+-ATPase, (d) H+-pumping activity, (e) H+ permeability of plasmalemma, and (f) pH gradient across the membranes of plasmalemma vesicles. In addition, vanadate sensitivity remained unchanged. It is concluded that plasmalemma H+-ATPase contributes significantly to the adaptation of corn roots to low pH. A restricted net H+ release at low pH in vivo may be attributed to the steeper pH gradient and enhanced H+ permeability of plasmalemma but not to deactivation of H+-ATPase. Possible mechanisms responsible for adaptation of plasmalemma H+-ATPase to low solution pH during plant cultivation are discussed.

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In this study, we analyze the impact of financial development and market conditions on investment-cash flow sensitivity during the 2006-2014 for 76 countries. First, the results show a relationship between investment-cash flow sensitivity and an index of financial development and its components. Second, 68 countries are affected by the 2008-2009 financial crisis, but only 16 countries exhibit a higher investment-cash flow sensitivity during the crisis. Third, investment-cash flow sensitivity is lower in countries with a larger primary debt market, while the size of the primary equity market has no impact. Finally, analyzing investment-cash flow sensitivity over time, we find lower sensitivity during years associated with higher primary debt market activity.

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CuO/ceria-zirconia catalysts have been prepared, deeply characterised (N2 adsorption–desorption isotherms at −196 °C, XRD, Raman spectroscopy, XPS, TEM and H2-TPR) and tested for NO oxidation to NO2 in TPR conditions, and for soot combustion at mild temperature (400 °C) in a NOx/O2 stream. The behaviour has been compared to that of a reference Pt/alumina commercial catalyst. The ceria-zirconia support was prepared by the co-precipitation method, and different amounts of copper (0.5, 1, 2, 4 and 6 wt%) were loaded by incipient wetness impregnation. The results revealed that copper is well-dispersed onto the ceria-zirconia support for the catalysts with low copper loading and CuO particles were only identified by XRD in samples with 4 and 6% of copper. A very low loading of copper increases significantly the activity for the NO oxidation to NO2 with regard to the ceria-zirconia support and an optimum was found for a 4% CuO/ceria-zirconia composition, showing a very high activity (54% at 348 °C). The soot combustion rate at 400 °C obtained with the 2% CuO/ceria-zirconia catalyst is slightly lower to that of 1% Pt/alumina in terms of mass of catalyst but higher in terms of price of catalyst.

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Different catalysts, based on heteropolyacids supported on activated carbon fibers, have been prepared for palmitic acid esterification reaction. The influence of the catalyst (heteropolyacid) and the support on the catalytic activity have been analyzed. The results prove that an adequate combination of both is required to achieve the most suitable catalysts. Regarding to the heteropolyacid, phosphomolybdic acid seems to be the most suitable appropriate taking into account its lowest leaching. About the support, it must show an optimum microporosity, which must be wide enough to allow the entrance and exit of the reagents and products but not too wide in order to avoid the leaching of the catalyst. In addition, both decreasing of the catalytic activity and its recovery over several cycles have been analyzed.

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An active hydrogenation Pd complex has been immobilised by impregnation on CNTs submitted to several treatments that lead to important differences in their surface chemistry and in the proportion of tubes with both ends open. Most of the hybrid catalysts are more active than the complex in homogeneous phase, but the support properties have an important impact in the catalytic activity. In general, the more developed the surface chemistry, the lower the activity. However, when CNTs are open at both ends, the Pd complex can enter the tubular cavity and an important enhancement of the catalytic activity due to a confinement effect is observed.

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The global financial crisis, which started in the summer of 2007 and deepened in the aftermath of the Lehman failure in September 2008, has led to a virtual collapse in economic activity and increased financial volatility worldwide. For the developing countries, the main channel of transmission has been a drop in external transactions, such as trade, financial and capital flows, and remittances. The emerging economies in the southern and eastern Mediterranean have also faced declining economic activity, although there seems to be considerable variation in the relative magnitude and timing. Most of these economies have shown a delayed but more lasting response to the crisis, driven mostly by their close trade and investment ties with the EU and the Gulf Cooperation Council (GCC) countries. This book explores the fiscal, monetary and financial effects of the crisis in the region and provides an in-depth analysis of the fiscal, monetary and banking policies in the post-crisis era, the viability of their exit strategies and the future of reforms in the region. These analyses not only provide a comprehensive comparison between the countries but also provide a solid basis for assessing future economic and financial developments and reforms in the region.

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Over the past five years, over-the-counter (OTC) derivatives markets have received heightened regulatory attention, due to their opaqueness, size and interconnectedness, with a view to improving the robustness, safety and resilience of this market segment. There has been continued progress in the follow-up to the G-20 commitments, with the EU (EMIR, MIFID II, CRD/CRR IV, MAD) and the US (Swap Execution Facility or SEF, Title VII of Dodd-Frank Act, Basel III) leading in the implementation timelines and capturing approximately 80-90% of the overall market. Based on the data compiled for the yearly ECMI Statistical Package, this commentary provides a snapshot of the current status of the global OTC derivatives markets by: i) identifying general trends over the past decade, ii) looking at the changes in the market structure (instruments and participants), iii) estimating the uncollateralised derivatives exposure and iv) examining the relationship between OTC derivatives and exchange-traded derivatives (ETD).

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The government debt crisis, erupted in the Eurozone in 2009, nearly led to the collapse of European monetary union. Now that this has been averted, the question is what should be done to make the Eurozone sustainable in the long run. The survival of the Eurozone hinges on the capacity of its leaders to improve the eurozone's governance. With the exception of Greece, the root cause of the government debt crisis has little to do with the poor performance of the SGP, rather, with unsustainable debt accumulation by private actors. Also, the method of convergence implicit in the SGP has not worked well – macroeconomic divergences have stubbornly remained for nearly a decade and several countries experienced boom and bust dynamics. Although strong declines in real interest rates may explain part of the story (but e.g. Italy did not experience boom & bust), self-fulfilling waves of optimism and pessimism which might be called 'animal spirits' and are of mainly national origin, seem a good candidate for explanation. These national animal spirits endogenously trigger credit expansion and contraction. It follows that (national) movements of credit ought to be under much firmer control and this is up to the monetary authorities, including the ECB. Critical recommendations for better governance of the Eurozone should therefore combine credible measures to maintain fiscal discipline over the medium term with such instruments as minimum reserve requirements to control the growth of bank credit as well as minimum reserve requirements in different national banking systems. Finally, the idea of adding more sanctions to the SGP may be ill-conceived since, in future, it might pre-empt national governments to come to the rescue of banks (under credible threats of contagion) and/or prevent a downward spiral in economic activity.

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A sensitive quantitative reversed-phase HPLC method is described for measuring bacterial proteolysis and proteinase activity in UHT milk. The analysis is performed on a TCA filtrate of the milk. The optimum concentration of TCA was found to be 4%; at lower concentrations, non-precipitated protein blocked the HPLC while higher concentrations yielded lower amounts of peptides. The method showed greater sensitivity and reproducibility than a fluorescamine-based method. Quantification of the HPLC method was achieved by use of an external dipeptide standard or a standard proteinase. (c) 2006 Elsevier Ltd. All rights reserved.