Search results for "Exchange"
showing 10 items of 2035 documents
Handling the epistemic uncertainty in the selective maintenance problem
2020
Abstract Nowadays, both continuous and discontinuous operating systems require higher and higher reliability levels in order to avoid the occurrence of dangerous or even disastrous consequences. Accordingly, the definition of appropriate maintenance policies and the identification of components to be maintained during the planned system’s downtimes are fundamental to ensure the reliability maximization. Therefore, the present paper proposes a mathematical programming formulation of the selective maintenance problem with the aim to maximize the system’s reliability under an uncertain environment. Specifically, the aleatory model related to the components’ failure process is well known, where…
Influence of the level of cytosolic epoxide hydrolase on the induction of sister chromatid exchanges by trans-beta-ethylstyrene 7,8-oxide in human ly…
1991
Abstract trans -β-Ethylstyrene 7,8-oxide, a substrate of cytosolic epoxide hydrolase, and 4-fluorochalcone oxide, an inhibitor of this enzyme, were investigated on induction of sister chromatid exchanges (SCE) in human lymphocytes. Both epoxides enhanced the frequency of SCE. 4-Fluorochalcone oxide at low concentration (2.5μM) inhibited cytosolic epoxide hydrolase activity towards trans -β-ethylstyrene 7,8-oxide in lymphocytes by 74% and had no effect on glutathione transferase activity using this substrate. At this concentration it did not induce SCE itself, but it potentiated the effect of trans -β-ethylstyrene 7,8-oxide several fold. In lymphocytes from different subjects, the number of …
Improving Pairs Trading Using Neural Network Techniques and Fundamental Ratios
2020
Pairs trading is a quantitative trading strategy consisting on identifying two stocks that historically move together and, using the assumption that their prices difference has mean- reverting properties, exploit the deviation from the mean by taking long – short position in the chosen pair to profit. Throughout the years, different approaches have been developed in order to exploit this strategy. However, there is little literature who looks whether the divergences in the prices are generated by poor company results, i.e. whether the deviation from the mean are product of bad (or good) fundamentals and are justified, or if they generate a new equilibrium point for the pair. In addition, si…
On the Talmud Division: Equity and Robustness
2008
The Talmud Division is a very old method of sharin g developed by the rabbis in the Talmud and brought to the fore in the modern area s ome authors, among them are Aumann and Maschler. One compares the Talmud Division to other methods, mainly here the most popular, Aristotle's Proportional Division, but also to the equal division. The Talmud Division is more egalitarian than the Proportional Division for smal l levels of estate and conversely and it protects the weakest -those who cannot place a non-zero clai m-. This suggests that claimants may choose among the claiming methods depending on their interest, what implies a metagame. Unlike other methods as the Proportional Division, the Talm…
The Euro-Dollar Exchange Rate: Is it Fundamental?
2002
In this paper we have applied two approaches to the study of the dollar real exchange rate in relation with the Euro-area currencies. First, using dynamic panel techniques, we estimate an error correction model for the dollar real exchange rate versus seven developed countries, four of them Euro-area members. Second, we aggregate the European variables and estimate a model for the Euro-dollar real exchange rate using time series techniques. After identification and model selection, the same specification can be adopted in the two cases, in an eclectic model including real interest rate and productivity differentials, together with relative fiscal policy and net foreign asset positions. This…
Interaction between N-terminal domain of H4 and DNA is regulated by the acetylation degree.
1998
Abstract To study whether the acetylation of one or more of the four acetylatable lysines of histone H4 affects its binding to DNA, we have designed a protection experiment with a model system consisting in phage lambda DNA as substrate, Stu I as restriction endonuclease and histone H4 with different degrees of acetylation as the protective agent. It can be deduced from the experimental data that the protection afforded by the histone is not dependent on the number of positive charges lost by acetylation. Thus, non-acetylated H4 and mono-acetylated H4 cause similar protection, while di-acetylation of the histone seems to be the crucial step in significantly weakening the interaction between…
Involvement of carboxyl groups in chloride transport and reversible DIDS binding to band 3 protein in human erythrocytes
2011
AbstractNoncovalent DIDS binding to Band 3 (AE1) protein in human erythrocyte membranes, modified by non-penetrating, water soluble 1-ethyl-3-(4-azonia-4,4-dimethylpentyl)-carbodiimide iodide (EAC), was studied at 0°C in the presence of 165 mM KCl. Under experimental conditions applied up to (48 ± 5) % of irreversible chloride self-exchange inhibition was observed. The apparent dissociation constant, KD, for “DIDS-Band 3” complex, determined from the chloride transport experiments, was (34 ± 3) nM and (80 ± 12) nM for control and EAC-treated resealed ghosts, respectively. The inhibition constant, Ki, for DIDS was (35 ± 6) nM and (60 ± 8) nM in control and EAC-treated ghosts, respectively. T…
Volatility transmission patterns and terrorist attacks
2009
The objective of this study is to analyze volatility transmission between the US and Eurozone stock markets considering the effects of the September 11, March 11 and July 7 financial crises. In order to do this, we use a multivariate GARCH model and take into account the asymmetric volatility phenomenon, the non-synchronous trading problem and the crises themselves. Moreover, a graphical analysis of the Asymmetric Volatility Impulse-Response Functions (AVIRF) is introduced, which takes into consideration the crisis effect. Results suggest that there is bidirectional and asymmetric volatility transmission and show the different impact that terrorist attacks had on both markets. El objetivo d…
The environmental benefits of carsharing: The case study of Palermo
2020
Abstract The problems related to traffic emissions are becoming increasingly pressing and serious, especially in big cities where the private car plays the main role in the mobility of people, being excessively used, while walking, cycling and the use of public transport are often seen as secondary options and are hampered by a poorly urban environment. Therefore, solutions must be found to reduce the number of cars circulating in the city and to support the most sustainable modes of transport at the same time, in order to reduce emissions of greenhouse gases and harmful substances. A modal alternative which is of undoubted interest could be represented by carsharing, which is a mode comple…
Non-parametric probabilistic forecasting of academic performance in Spanish high school using an epidemiological modelling approach
2013
Academic underachievement is a concern of paramount importance in Europe, and particularly in Spain, where around of 30% of the students in the last two courses in high school do not achieve the minimum knowledge academic requirement. In order to analyse this problem, we propose a mathematical model via a system of ordinary differential equations to study the dynamics of the academic performance in Spain. Our approach is based on the idea that both, good and bad study habits, are a mixture of personal decisions and influence of classmates. Moreover, in order to consider the uncertainty in the estimation of model parameters, a bootstrapping approach is employed. This technique permits to for…