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Data on educational attainments are often qualitative data where the only information available is the highest level of education of the individual. If these levels of education may be ranked, the ...

During the last decade, Third-Party Logistics (3PLs) became a key component of industrial organisations and, consequently, of their performance. This article provides an analysis of the productive ...

The HIV protein Vpr interacts with EB1, p150Glued, and dynein heavy chain and perturbs the centripetal movement of phagosomes and their maturation, resulting in impaired phagolysosome biogenesis, which is important for bacterial clearance and cytokine production., Human immunodeficiency virus type 1 (HIV-1) impairs major functions of macrophages but the molecular basis for this defect remains poorly characterized. Here, we show that macrophages infected with HIV-1 were unable to respond efficiently to phagocytic triggers and to clear bacteria. The maturation of phagosomes, defined by the presence of late endocytic markers, hydrolases, and reactive oxygen species, was perturbed in HIV-1–infected macrophages. We showed that maturation arrest occurred at the level of the EHD3/MICAL-L1 endosomal sorting machinery. Unexpectedly, we found that the regulatory viral protein (Vpr) was crucial to perturb phagosome maturation. Our data reveal that Vpr interacted with EB1, p150Glued, and dynein heavy chain and was sufficient to critically alter the microtubule plus end localization of EB1 and p150Glued, hence altering the centripetal movement of phagosomes and their maturation. Thus, we identify Vpr as a modulator of the microtubule-dependent endocytic trafficking in HIV-1–infected macrophages, leading to strong alterations in phagolysosome biogenesis.

Migration has traditionally been used as a survival strategy in times of financial crisis; however, a debate exists as to whether migration influences poverty on the individual level. The current study analyses the influence of past subjective poverty on migration choice and to determine the impact of migration on current subjective poverty perception. Using a simultaneous bivariate ordered probit model, we found that poorer individuals in Egypt tend to migrate more than others. Migration was found to be a significant determinant of current poverty in Egypt. Finally, migration improved migrant’s financial situation.

This paper takes a new look at the determinants of cognitive ability. Using the results of the 2006 PISA survey for five Latin American countries (Brazil, Chile, Colombia, Mexico and Uruguay) it adopts an efficiency analysis perspective. Rather than selecting as inputs a few variables, it integrates the maximum amount of available information via the use of correspondence analysis (CA). Efficiency is estimated at the individual level via corrected ordinary least squares and is then regressed on explanatory variables obtained again via correspondence analysis. Unobserved school effects are taken into account by estimating a random effect model. Finally, using the so-called Shapley decomposition, we determine the exact impact on individual efficiency of each of the factors that are considered as determinants of this efficiency.

In a recent paper Ramos and Silber (2005) used techniques developed in efficiency analysis to obtain estimates of human development obtained on the basis of Sen (1985) and Narayan et al. (2000) capability approach. In particular they propose to measure standard achievement and well being indexes using a distance function approach. In this paper, it is shown that the ratio based of well-being and standard achievement indexes form the Hicks–Moorsteen index introduced by Bjurek (1996). Along this line, an additive form of the standard achievement and well-being indexes is proposed. In particular, the paper focusses on the case of social inputs. Axiomatic and dual properties are established and some parametric and nonparametric models are proposed.

Macrophages are phagocytic cells that play a major role at the crossroads between innate and specific immunity. They can be infected by the human immunodeficiency virus (HIV)-1 and because of their resistance to its cytopathic effects they can be considered to be persistent viral reservoirs. In addition, HIV-infected macrophages exhibit defective functions that contribute to the development of opportunistic diseases. The exact mechanism by which HIV-1 impairs the phagocytic response of macrophages was unknown. We had previously shown that the uptake of various particulate material by macrophages was inhibited when they were infected with HIV-1. This inhibition was only partial and phagosomes did form within HIV-infected macrophages. Therefore, we focused on analyzing the fate of these phagosomes. Phagosome maturation is accompanied by migration of these compartments towards the cell center, where they fuse with lysosomes, generating phagolysosomes, responsible for degradation of the ingested material. We used IgG-opsonized Sheep Red Blood Cells as a target for phagocytosis. To measure the speed of centripetal movement of phagosomes in individual HIV-infected macrophages, we used a combination of bright field and fluorescence confocal microscopy. We established a method to calculate the distance of phagosomes towards the nucleus, and then to calculate the velocity of the phagosomes. HIV-infected cells were identified thanks to a GFP-expressing virus, but the method is applicable to non-infected cells or any type of infection or treatment.

B lymphocytes can be triggered in lymph nodes by nonopsonized antigens (Ag), potentially in their native form. However, the mechanisms that promote encounter of B lymphocytes with unprocessed antigens in lymph nodes are still elusive. We show here that antigens are detected in B cells in the draining lymph nodes of mice injected with live, but not fixed, dendritic cells (DCs) loaded with antigens. This highlights active processes in DCs to promote Ag transfer to B lymphocytes. In addition, antigen-loaded DCs found in the draining lymph node were CD103+. Using 3 different model Ag, we then show that immature DCs efficiently take up Ag by macropinocytosis and store the internalized material in late endocytic compartments. We find that DCs have a unique ability to release antigens from these compartments in the extracellular medium, which is controlled by Rab27. B cells take up the regurgitated Ag and the chemokine CXCL13, essential to attract B cells in lymph nodes, enhances this transfer. Our results reveal a unique property of DCs to regurgitate unprocessed Ag that could play an important role in B-cell activation.

In the search for inhibitors of the replication of RNA viruses, including hepatitis C virus (HCV), the hitherto unknown 4'-C-azidomethyl-beta-D-ribofuranosyl nucleosides of the five naturally occurring nucleic acid bases have been synthesized and their antiviral properties examined. These 4'-C-branched nucleosides were stereospecifically prepared by glycosylation of purine and pyrimidine aglycons with a suitable peracylated 4-C-azidomethyl-D-pentofuranose sugar, followed by removal of the protecting groups. The prepared compounds were tested for their activity against several viruses, but they did not show an antiviral effect.

An extensive literature has evolved, particularly in the United States, around the notion of social cohesion. This literature marks a shift away from sociological ideas of the past. It reflects the profound economic and social changes that societies have undergone in the last 30 years under the impact of successive crises, the development of market relations in most spheres of social life and the effects of globalisation. As at other times in the past, these changes call into question what it means ‘to live in society’. The notion of social cohesion has been the subject of considerable debate (for example Chan et al., 2006; Green et al., 2006; Dubet et al., 2010). The arguments have been all the more intense since various countries have put the spotlight on social cohesion as the foundation and/or goal of public policies. Thus the European Union (EU), for example, has offered member states a set of targets and indicators linked to social cohesion as part of the ‘European social model’. Similarly, in Canada (Patrimoine Canadien, 2004; Jeannotte, 2000) several government reports have examined this issue.

As part of the so-called Lisbon process, the European Union (EU) has strongly emphasised the importance of education and training systems for the knowledge society. Recommendations aimed at member states have gradually been developed, based on indicators of objectives to be achieved. The open method of coordination has been extended to encompass vocational training. In the field of higher education, we are familiar with the so-called ‘Bologna’ process, which seeks among other things to harmonise the three main levels of education across Europe. Over the past 30 years, the majority of European countries have seen strong growth in the numbers of pupils pursuing their studies to upper secondary. This trend has been continued by the advent of mass higher education. As part of this exchange of good practice between countries, objectives have been set, including in an area entitled ‘making lifelong learning a reality’, another entitled ‘improving equity in education and training’ and a third called ‘key competences for young people’ (Commission Europeenne, 2007, pp. 3–4).

PurposeThe purpose of this paper is to evaluate the effects of job‐training programs, initiated by the Moroccan government and called “special training contracts”, on the performance of Moroccan firms.Design/methodology/approachTwo databases (MICT, OFPPT) of Moroccan firms were considered. Matched databases were completed using a questionnaire survey. Panel data with 322 firms from 2001 to 2003 were obtained.FindingsThe paper highlights that “special training contracts” is an efficient measure of public policy. Indeed, job‐training programs increase the competitiveness and performance of Moroccan firms. Additionally, it was shown that firms have different perceptions of the role of public policy. It was emphasised that training effects are higher when training is considered as part of a human resources development strategy. On the contrary, when firms view public policy as just a financing opportunity, they do not get any returns from training.Practical implicationsA better understanding of the role of STC may increase training efficiency.Originality/valueThe case of an emerging country, Morocco, was studied. The conclusion of the analysis could provide solutions linking human resources management to issues of growth and long‐term development.

This paper investigates the relation between advances in technology and trends in the gender wage gaps in the US service industry. Using quarterly US Current Population Survey data on employment and wages by four major occupations between 1979 and 2001, the paper estimates a constant elasticity of substitution production function (CES) that incorporates male and female labor inputs, a non-labor input and a productivity parameter function that captures non-neutral technological change. The model is estimated by two stage least squares (2SLS) with cross-equation restrictions. The results reveal a narrowing effect of technological change on the female-male wages for the highest skill level occupation (managerial, professional occupations). This effect is robust to controlling for the unexplained gender wage gap and to using direct measures of technological change. The effect of technological change on the gender wage gaps for the other skill levels tends to diminish or disappear altogether once changes in unexplained gender wage gaps are adjusted for. The results highlight the importance of considering the unexplained gender wage gaps in examining the effect of technological change on the gender wage gaps.

The aim of this chapter is to analyze the sources of earnings dispersion between trainees and nontrainees. We stress three mechanisms by which investment in general training may affect wage inequality: directly via participation to a general training program and indirectly via the selection process of trainees or the existence of heterogeneous returns on training. This chapter adopts an approach originally proposed by Fields (2003) but extends it to the breakdown of inequality by population subgroups – those who received training and those who did not. The empirical illustration is based on four French surveys, the 2006 Adult Educational Survey and the 2004, 2005, and 2006 Labor Force Surveys that complement it.

Determining the allocation and the distribution of scarce resources is fundamental in economics. Thus, decision theory is the cornerstone of economic theory. In this thesis, we first provide a state of the art insisting on the fact that information, that is a central element of decision-making, is imperfect. Secondly, using fuzzy set theory, which aims to capture imprecision, we construct a fuzzy number, so-called C-Shape that captures the sensitivity of the decision-maker. Thirdly, we study decision theory through two key concepts of operation research: (1) game theory and (2) multi-criteria decision making. We provide an analogy between the gauge functions of convex sets and the membership functions arising in fuzzy set theory. Coupling a suitable notion of -convexity with the C-Shape function, we introduce a class of games for which the players can be optimistic, pessimistic or neutral. In addition the existence of Nash equilibrium is proved for such a class of games. Finally, concerning multi-criteria decision analysis, we use the C-Shape functions to characterize a new type of criteria called C-Shape pseudo-criterion, which makes possible to consider the alternatives as substitutable. This should be of interest to take into account, for example, the institutional context in which decision-making is taken., En sciences économiques, l'une des questions centrales concerne l'allocation des ressources rares et plus particulièrement leur répartition. La décision apparait ainsi au cœur des thématiques économiques, que ce soit en micro-économie ou en macro-économie. Dans un premier temps, nous revenons sur le fait que l’information, élément central de la prise de décision, est imparfaite. En utilisant la théorie des ensembles flous, qui a pour objet de capturer l’imprécision, nous construisons un nombre flou nommé nombre flou C-Shape qui permet de capter la sensibilité du preneur de décision. Nous étudions ensuite la théorie de la décision au travers de deux axes de recherche à savoir (1) la recherche opérationnelle couplée à la théorie des jeux et (2) l’aide à la décision. En premier lieu, Nous faisons une analogie entre la fonction distance et la fonction d’appartenance. Grâce à l’hypothèse de B-convexité et à la fonction C-Shape nous construisons des classes de jeux pour lesquels les joueurs peuvent être optimistes, pessimistes ou neutres, et pour lesquels l’existence d’équilibre de Nash est avérée. Enfin, concernant l’aide à la décision, nous utilisons la fonction C-Shape pour caractériser un nouveau type de critère nommé pseudo critère C-Shape qui permet de considérer les alternatives comme substituables. Ceci permet de prendre en compte, par exemple le contexte institutionnel dans lequel la prise de décision est prise.

This thesis aims to present two efficiency measures. First, a log-additive distance function is introduced. It is dual to non-linear pseudo cost, revenue and profit functions. This structure means that the relation between factors and products is not constant. Moreover, exponential Luenberger (Chambers, Färe and Grosskopf (1996)) and Luenberger-Hicks-Moorsteen (Briec and Kerstens (2004)) indicators are proposed. Second, a non-linear distance function is defined. It inherits thestructure of CES (Solow (1956)) and CET (Powell and Gruen (1968))functions. The duality theory allows to present non-linear cost, revenue and profit functions. In this sense, non-linear adjusted price functions are deduced. Non-linear prices occur when the production unit faces internal and/or non-linear tariffs. The alpha-returns to scale model (Boussemart, Briec, Peypoch and Tavéra (2009)) is applied to this new non-linear efficiency measure. Indeed, it is shown that returns-to-scale impact efficiency of production units.; Ces travaux proposent deux nouvelles mesures de l’efficience. La première est une fonction de distance log-additive qui peut être orientée soit en input, soit en output, soit dans le graphe. Celle-ci est duale à des pseudo fonctions de coût, de revenu et de profit non-linéaires. Cette structure des fonctions, indique une relation non-constante entre les intrants et les extrants. Cet outil de mesure de l’efficacité peut servir à estimer la variation de la productivité dans le temps. A cet effet,nous proposons des indicateurs de productivité, de type Luenberger (Chambers, Färe et Grosskopf (1996)) et Luenberger-Hicks-Moorsteen (Briec et Kerstens (2004)), exponentiels. La seconde mesure, est une fonction de distance non-linéaire structurellement inspiré des fonctions CES (Solow (1956)) et CET (Powell et Gruen (1968)). La théorie de la dualité amène à présenter des fonctions de coût, de revenu et de profit non-linéaires. De ce fait, des fonctions de prix ajustés non-linéairesen sont déduites. Une telle structure des prix peut être rencontrée lorsque les unités productives font face à des tarifications non-linéaires en interne et, en externe. Nous appliquons cette nouvelle mesure de l’efficacité au modèle de rendements d’échelle alpha (Boussemart, Briec, Peypoch et Tavéra)(2009)). En effet, ce modèle permet d’estimer l’influence des rendements d’échelle sur l’efficacité.