Search results for "COMPLEMENTARITY"
showing 10 items of 89 documents
The role of positive selection in hepatitis C virus
2008
Hepatitis C virus (HCV) is a major health problem worldwide, infecting an estimated 170 million people. In this study, we have employed a large data set of sequences (14,654 sequences from between 25 and 100 clone sequences per analyzed region and per patient) from 67 patients infected with HCV genotype 1 (23 subtype 1a and 44 subtype 1b). For all patients, a sample prior to combined therapy with alpha interferon plus ribavirin was available, whereas for some patients additional samples after 6 or 12 months of treatment were also available. Twenty-seven patients responded to treatment (12 subtype 1a and 15 subtype 1b) and forty patients did not respond to treatment (11 subtype 1a vs. 29 sub…
Using evolutionary tools to refine the new hypervariable region 3 within the envelope 2 protein of hepatitis C virus
2007
Abstract The envelope 2 protein of hepatitis C virus (HCV) presents three hypervariable regions, named HVR1, HVR2 and HVR3, in which the presence of antigenic sites has been described. Genetic variability in these regions may reflect the generation of escape mutants as a consequence of the immune response. Therefore, these regions would tend to accumulate amino acid changes along the infection process, an effect that could be accelerated by antiviral treatments. In this study, we have analyzed the E1–E2 region of 23 HCV patients non-responders to antiviral treatment, 7 of which were infected with subtype 1a, 15 with subtype 1b, and 1 with a new HCV-1 subtype, before and after 6 and/or 12 mo…
Product and service bundling decisions and their effects on purchase intention
1997
Examines the effects of four factors (the bundle: pure or mixed, the price discount, the functional complementarity of bundle components, and the number of bundle components) on consumers’ intentions to purchase product and service bundles. The findings were relatively consistent across product (automobile) and service (automotive service) contexts, and illustrate that pure bundles are preferred to mixed bundles, and a greater price discount is preferred to a lesser one. The results also indicate that five component bundles generate greater purchase intention than either three or seven component bundles, and that “very related” bundle components result in greater purchase intention than eit…
Self-Enforcing International Environmental Agreements: Adaptation and Complementarity
2018
This paper studies the impact of adaptation on the stability of an international emission agreement. To address this issue we solve a three-stage coalition formation game where in the first stage countries decide whether or not to sign the agreement. Then, in the second stage, signatories (playing together) and non-signatories (playing individually) select their levels of emissions. Finally, in the third stage, each country decides on its level of adaptation non co-operatively. We solve this game for two models. For both, it is assumed that damages are linear with respect to emissions which guarantee that emissions are strategic complements in the second stage of the game. However, for the …
What Explains Governance Structure in Non-Profit and For-Profit Microfinance Institutions?
2009
This paper aims to explain the choice of board and CEO characteristics in microfinance institutions (MFI). Explanations are sought in substitution or complementarity between the characteristics, external governance variables, and financial performance and outreach performance to the poor. The data are from 290 MFIs in 61 countries, and the logit regressions methodology is employed. The board and CEO characteristics are board size, CEO-chairman duality, international directors, and female CEO. We find relationships among these variables, and also that the external governance variables ownership type (shareholder owned) and international initialization induce smaller board, less duality, more…
Audit Quality and Corporate Governance: Evidence from the Microfinance Industry
2015
This study uses a unique hand-collected sample of for-profit and nonprofit microfinance institutions from 70 developing countries to analyse the relationships between audit quality and governance mechanisms. We examine two measures of audit quality, namely, the use of Big Four auditors and the presence of internal auditors. The empirical analysis of this study reveals that these two quality metrics are highly related, although we also demonstrate that these metrics capture distinctive aspects of audit quality. In particular, the presence of internal auditors is related to other indicators of stricter governance, whereas the use of Big Four auditors is generally unrelated to other governance…
Domain specific language for securities settlement systems
2012
Actual problems during design, implementation and maintenance of securities settlement systems software are achieving complementarity of several different, connected, asynchronously communicating settlement systems and verification of this complementarity. The aim of this paper is to create domain specific language for modeling of settlement systems and their interactions. Then use models to calculate settlement systems behavior. Specific of settlement systems requires that they perform accordingly to business rules in any situation. This makes use of model checking a very desirable step in development process of settlement systems. Defining a domain specific language and creating editor su…
A thermodynamically consistent nonlocal formulation for damaging materials
2002
A thermodynamically consistent nonlocal formulation for damaging materials is presented. The second principle of thermodynamics is enforced in a nonlocal form over the volume where the dissipative mechanism takes place. The nonlocal forces thermodynamically conjugated are obtained consistently from the free energy. The paper indeed extends to elastic damaging materials a formulation originally proposed by Polizzotto et al. for nonlocal plasticity. Constitutive and computational aspects of the model are discussed. The damage consistency conditions turn out to be formulated as an integral complementarity problem and, consequently, after discretization, as a linear complementarity problem. A n…
Efficient numerical methods for pricing American options under stochastic volatility
2007
Five numerical methods for pricing American put options under Heston's stochastic volatility model are described and compared. The option prices are obtained as the solution of a two-dimensional parabolic partial differential inequality. A finite difference discretization on nonuniform grids leading to linear complementarity problems with M-matrices is proposed. The projected SOR, a projected multigrid method, an operator splitting method, a penalty method, and a componentwise splitting method are considered. The last one is a direct method while all other methods are iterative. The resulting systems of linear equations in the operator splitting method and in the penalty method are solved u…
Active macro-zone approach for incremental elastoplastic-contact analysis
2013
SUMMARY The symmetric boundary element method, based on the Galerkin hypotheses, has found an application in the nonlinear analysis of plasticity and in contact-detachment problems, but both dealt with separately. In this paper, we want to treat these complex phenomena together as a linear complementarity problem. A mixed variable multidomain approach is utilized in which the substructures are distinguished into macroelements, where elastic behavior is assumed, and bem-elements, where it is possible that plastic strains may occur. Elasticity equations are written for all the substructures, and regularity conditions in weighted (weak) form on the boundary sides and in the nodes (strong) betw…