79 resultados para Electron accepting unit
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Investigación producida a partir de una estancia en la London South Bank University, Reino Unido, entre los meses de setiembre y diciembre del 2005. Se estudia el trabajo sexual en el Reino Unido desde tres perspectivas diferentes. Por una parte, se trata la historia del feminismo anglosajón respecto a sus visiones sobre la prostitución, desde una aproximación a las fuentes. Por otra parte, se plantea la situación jurídico-política. Finalmente, se presenta brevemente a las principales entidades que dan apoyo al colectivo de trabajadoras del sexo en la ciudad de Londres.
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In this paper we study basic properties of the weighted Hardy space for the unit disc with the weight function satisfying Muckenhoupt's (Aq) condition, and study related approximation problems (expansion, moment and interpolation) with respect to two incomplete systems of holomorphic functions in this space.
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Estudi elaborat a partir d’una estada al Center for Socio-Legal Studies de la Universitat d’Oxford, Gran Bretanya, entre setembre del 2006 i gener del 2007. L'objectiu d'aquesta recerca ha estat determinar i avaluar com la política de la competència de la Unió Europea ha contribuït a la configuració del sector públic televisiu espanyol i britànic. El marc teòric està basat en el concepte d’ “europeització”, desenvolupat per Harcourt (2002) en el sector de mitjans, i que implica una progressiva referencialitat de les polítiques estatals amb les europees mitjançant dos mecanismes: la redistribució de recursos i els efectes en la socialització de la política europea. Per tal de verificar aquest impacte en el sector televisiu, la recerca ha desenvolupat una aproximació en dues etapes. En primer lloc, a banda de fer un inicial repàs bibliogràfic s'han estudiat les accions de la Comissió Europea en aquest terreny, sobre tot la Comunicació sobre aplicació de la reglamentació d'ajudes públiques al sector de la radiodifusió de 2001. En una segona etapa, s'han desenvolupat un seguit d'entrevistes personals a directius i polítics del sector a Brussel•les, Londres i Madrid. Els resultats de la recerca mostren que el procés d’Europeïtzació es un fenomen creixent en el sector audiovisual públic a Espanya i el Regne Unit, però que encara les peculiaritats estatals juguen un factor preponderant en regular aquesta influència de la UE. L'anàlisi de les entrevistes qualitatives mostren també que hi ha una relació inversament proporcional entre la tradició democràtica i el grau d’influència i de referència que suposa la UE en el sector audiovisual. Mentre que el Regne Unit, l'acció de la política de la competència de la UE es percep com a element suplementari, a Espanya la seva referencialitat ha estat clau, tot i que no decisiva, per la reforma dels mitjans públics estatals.
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This paper tests for real interest parity (RIRP) among the nineteen major OECD countries over the period 1978:Q2-1998:Q4. The econometric methods applied consist of combining the use of several unit root or stationarity tests designed for panels valid under cross-section dependence and presence of multiple structural breaks. Our results strongly support the fulfillment of the weak version of the RIRP for the studied period once dependence and structural breaks are accounted for.
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A multiple-partners assignment game with heterogeneous sales and multiunit demands consists of a set of sellers that own a given number of indivisible units of (potentially many different) goods and a set of buyers who value those units and want to buy at most an exogenously fixed number of units. We define a competitive equilibrium for this generalized assignment game and prove its existence by using only linear programming. In particular, we show how to compute equilibrium price vectors from the solutions of the dual linear program associated to the primal linear program defined to find optimal assignments. Using only linear programming tools, we also show (i) that the set of competitive equilibria (pairs of price vectors and assignments) has a Cartesian product structure: each equilibrium price vector is part of a competitive equilibrium with all optimal assignments, and vice versa; (ii) that the set of (restricted) equilibrium price vectors has a natural lattice structure; and (iii) how this structure is translated into the set of agents' utilities that are attainable at equilibrium.
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We use historical data that cover more than one century on real GDP for industrial countries and employ the Pesaran panel unit root test that allows for cross-sectional dependence to test for a unit root on real GDP. We find strong evidence against the unit root null. Our results are robust to the chosen group of countries and the sample period. Key words: real GDP stationarity, cross-sectional dependence, CIPS test. JEL Classification: C23, E32
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iii. Catheter-related bloodstream infection (CR-BSI) diagnosis usually involves catheter withdrawal. An alternative method for CR-BSI diagnosis is the differential time to positivity (DTP) between peripheral and catheter hub blood cultures. This study aims to validate the DTP method in short-term catheters. The results show a low prevalence of CR-BSI in the sample (8.4%). The DTP method is a valid alternative for CR-BSI diagnosis in those cases with monomicrobial cultures (80% sensitivity, 99% specificity, 92% positive predictive value, and 98% negative predictive value) and a cut-off point of 17.7 hours for positivity of hub blood culture may assess in CR-BSI diagnosis.
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A topological analysis of intracule and extracule densities and their Laplacians computed within the Hartree-Fock approximation is presented. The analysis of the density distributions reveals that among all possible electron-electron interactions in atoms and between atoms in molecules only very few are located rigorously as local maxima. In contrast, they are clearly identified as local minima in the topology of Laplacian maps. The conceptually different interpretation of intracule and extracule maps is also discussed in detail. An application example to the C2H2, C2H4, and C2H6 series of molecules is presented
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The electron localization function (ELF) has been proven so far a valuable tool to determine the location of electron pairs. Because of that, the ELF has been widely used to understand the nature of the chemical bonding and to discuss the mechanism of chemical reactions. Up to now, most applications of the ELF have been performed with monodeterminantal methods and only few attempts to calculate this function for correlated wave functions have been carried out. Here, a formulation of ELF valid for mono- and multiconfigurational wave functions is given and compared with previous recently reported approaches. The method described does not require the use of the homogeneous electron gas to define the ELF, at variance with the ELF definition given by Becke. The effect of the electron correlation in the ELF, introduced by means of configuration interaction with singles and doubles calculations, is discussed in the light of the results derived from a set of atomic and molecular systems
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A comparision of the local effects of the basis set superposition error (BSSE) on the electron densities and energy components of three representative H-bonded complexes was carried out. The electron densities were obtained with Hartee-Fock and density functional theory versions of the chemical Hamiltonian approach (CHA) methodology. It was shown that the effects of the BSSE were common for all complexes studied. The electron density difference maps and the chemical energy component analysis (CECA) analysis confirmed that the local effects of the BSSE were different when diffuse functions were present in the calculations
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The effect of basis set superposition error (BSSE) on molecular complexes is analyzed. The BSSE causes artificial delocalizations which modify the first order electron density. The mechanism of this effect is assessed for the hydrogen fluoride dimer with several basis sets. The BSSE-corrected first-order electron density is obtained using the chemical Hamiltonian approach versions of the Roothaan and Kohn-Sham equations. The corrected densities are compared to uncorrected densities based on the charge density critical points. Contour difference maps between BSSE-corrected and uncorrected densities on the molecular plane are also plotted to gain insight into the effects of BSSE correction on the electron density
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Quantum molecular similarity (QMS) techniques are used to assess the response of the electron density of various small molecules to application of a static, uniform electric field. Likewise, QMS is used to analyze the changes in electron density generated by the process of floating a basis set. The results obtained show an interrelation between the floating process, the optimum geometry, and the presence of an external field. Cases involving the Le Chatelier principle are discussed, and an insight on the changes of bond critical point properties, self-similarity values and density differences is performed
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The level of ab initio theory which is necessary to compute reliable values for the static and dynamic (hyper)polarizabilities of three medium size π-conjugated organic nonlinear optical (NLO) molecules is investigated. With the employment of field-induced coordinates in combination with a finite field procedure, the calculations were made possible. It is stated that to obtain reasonable values for the various individual contributions to the (hyper)polarizability, it is necessary to include electron correlation. Based on the results, the convergence of the usual perturbation treatment for vibrational anharmonicity was examined
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Electronic coupling Vda is one of the key parameters that determine the rate of charge transfer through DNA. While there have been several computational studies of Vda for hole transfer, estimates of electronic couplings for excess electron transfer (ET) in DNA remain unavailable. In the paper, an efficient strategy is established for calculating the ET matrix elements between base pairs in a π stack. Two approaches are considered. First, we employ the diabatic-state (DS) method in which donor and acceptor are represented with radical anions of the canonical base pairs adenine-thymine (AT) and guanine-cytosine (GC). In this approach, similar values of Vda are obtained with the standard 6-31 G* and extended 6-31++ G* basis sets. Second, the electronic couplings are derived from lowest unoccupied molecular orbitals (LUMOs) of neutral systems by using the generalized Mulliken-Hush or fragment charge methods. Because the radical-anion states of AT and GC are well reproduced by LUMOs of the neutral base pairs calculated without diffuse functions, the estimated values of Vda are in good agreement with the couplings obtained for radical-anion states using the DS method. However, when the calculation of a neutral stack is carried out with diffuse functions, LUMOs of the system exhibit the dipole-bound character and cannot be used for estimating electronic couplings. Our calculations suggest that the ET matrix elements Vda for models containing intrastrand thymine and cytosine bases are essentially larger than the couplings in complexes with interstrand pyrimidine bases. The matrix elements for excess electron transfer are found to be considerably smaller than the corresponding values for hole transfer and to be very responsive to structural changes in a DNA stack
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One of the strategies of Universitat Pompeu Fabra to support Quality Learning has been the creation of Units for the Support of Teaching Quality and Innovation within each faculty. In the seminar we will present the role and activities of the Polytechnic School Unit in charge or coordinating the efforts towards quality learning in the Information and Communication Technologies (ICT) Engineering Studies. We will also discuss how these activities are informed to relevant academic stakeholders.