Search results for "SETS"
showing 10 items of 592 documents
A Note on Algebraic Sums of Subsets of the Real Line
2002
AbstractWe investigate the algebraic sums of sets for a large class of invari-ant ˙-ideals and ˙- elds of subsets of the real line. We give a simpleexample of two Borel subsets of the real line such that its algebraicsum is not a Borel set. Next we show a similar result to Proposition 2from A. Kharazishvili paper [4]. Our results are obtained for ideals withcoanalytical bases. 1 Introduction We shall work in ZFC set theory. By !we denote natural numbers. By 4wedenote the symmetric di erence of sets. The cardinality of a set Xwe denoteby jXj. By R we denote the real line and by Q we denote rational numbers. IfAand Bare subsets of R n and b2R , then A+B= fa+b: a2A^b2Bgand A+ b= A+ fbg. Simila…
Ranking fuzzy interval numbers in the setting of random sets – further results
1999
Abstract We present some new properties of several fuzzy order relations, defined on the set of fuzzy numbers, from among those introduced in [S. Chanas, M. Delgado, J.L. Verdegay, M.A. Vila, Information Sciences 69 (1993) 201–217]. The main result is proving that four from among the relations considered in [S. Chanas, M. Delgado, J.L. Verdegay, M.A. Vila, Information Sciences 69 (1993) 201–217] are strongly transitive (s-transitive).
Almost disjoint families of countable sets and separable complementation properties
2012
We study the separable complementation property (SCP) and its natural variations in Banach spaces of continuous functions over compacta $K_{\mathcal A}$ induced by almost disjoint families ${\mathcal A}$ of countable subsets of uncountable sets. For these spaces, we prove among others that $C(K_{\mathcal A})$ has the controlled variant of the separable complementation property if and only if $C(K_{\mathcal A})$ is Lindel\"of in the weak topology if and only if $K_{\mathcal A}$ is monolithic. We give an example of ${\mathcal A}$ for which $C(K_{\mathcal A})$ has the SCP, while $K_{\mathcal A}$ is not monolithic and an example of a space $C(K_{\mathcal A})$ with controlled and continuous SCP …
Biochemical markers in Celiac disease.
2009
Celiac Disease is a worldwide spread condition affecting 1:100-1:200 individuals. It is a permanent food intolerance to ingested gluten in genetically predisposed subjects. In this review we analyze the biochemical markers of the disease going from laboratory findings to histology passing through genetics. Gluten intolerance is a unique model of autoimmune disease in which we can recognize the main environmental factor (gluten) and the more complex genetic background. In additional way, serological markers for monitoring the disease and a safe and effective therapy (gluten free diet) are also available. In deed the environmental factor such as gluten intake is necessary to trigger the disea…
An Exploratory Study of Financial Performance in CEE Countries
2020
Our research investigates the performance of companies from Central and Eastern European (CEE) countries in the period after the Global Financial Crisis of 2007-2009 with the aim of identifying the driving factors behind accounting- and market-based performance. We include in the analysis companies from various industries in CEE countries that are European Union members and we study their performance between 2008-2016 over the following areas of performance: liquidity, solvency and indebtedness, operational profitability, global performance (through Return on assets and Return on equity), returns available to shareholders and market-based performance (through price/book value and Tobin Q …
Unbundling technology adoption and tfp at the firm level. Do intangibles matter?
2012
We use a panel of European firms to investigate the relationship between intangible assets and productivity. We distinguish between total factor productivity (tfp) and technology adoption, whereas standard estimations consider only a notion of productivity that conflates the two effects. Although we are unable to address simultaneity, we allow for the existence of multiple technologies within sectors through a mixture model approach. We find that intangible assets have nonnegligible effects that both push firms toward better technologies (technology adoption effects) and allow for more efficient exploitation of a given technology (tfp effects).
Predicting failure in the U.S. banking sector: An extreme gradient boosting approach
2019
Abstract Banks play a central role in developed economies. Consequently, systemic banking crises destabilize financial markets and hamper global economic growth. In this study, extreme gradient boosting was used to predict bank failure in the U.S. banking sector. Key variables were identified to anticipate and prevent bank defaults. The data, which spanned the period 2001 to 2015, consisted of annual series of 30 financial ratios for 156 U.S. national commercial banks. Identifying leading indicators of bank failure is vital to help regulators and bank managers act swiftly before distressed financial institutions reach the point of no return. The findings indicate that lower values for retai…
Crypto market responses to digital asset policies
2023
We construct daily databases of crypto bans and policy statements concerning central bank digital currencies (CBDCs) to estimate their effect on crypto trading volumes for an unbalanced panel of 116 countries from November 2016 to December 2021. We find that trading volume falls by up to 55% in the week after the announcement of a ban, and by up to 25% after a CBDC-supportive speech by senior central bank officials. For the strictest bans, this reduction persists over the subsequent quarter, driven by a reduction in trading by institutional investors. The results suggest that crypto market participants pay significant attention to government policy on digital assets.(c) 2022 Elsevier B.V. A…
Homing and memory patterns of human gammadelta T cells in physiopathological situations.
2004
Vgamma9Vdelta2 are a heterogeneous population of T cells and comprise distinct naive, memory and effector populations that can be distinguished on the basis of surface marker expression and effector functions. We review here these recently studied features of Vgamma9Vdelta2 T lymphocyte biology and the roles they play in infectious and autoimmune diseases.