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The paper introduces in social choice theory a directional distance function (DDF) that quantifies the level of inefficiency of a given allocation with respect to the utility possibilities frontier. The paper shows that the DDF has a simple geometric interpretation and involves a complete transitive preference relation. If the uility possibilities set is not convex, it is shown that the Rawls welfare function is dual (in a certain sense) to the DDF. Finally a more general class of distance functions is introduced that is shown to be closely related to a large class of welfare functions widely used in the study of economic inequality.

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.

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.

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.