Study of the Wealth Inequality in the Minority Game

To demonstrate the usefulness of physical approaches for the study of realistic economic systems, we investigate the inequality of players' wealth in one of the most extensively studied econophysical models, namely, the minority game (MG). We gauge the wealth inequality of players in the MG by a well-known measure in economics known as the modified Gini index. From our numerical results, we conclude that the wealth inequality in the MG is very severe near the point of maximum cooperation among players, where the diversity of the strategy space is approximately equal to the number of strategies at play. In other words, the optimal cooperation between players comes hand in hand with severe wealth inequality. We also show that our numerical results in the asymmetric phase of the MG can be reproduced semi-analytically using a replica method.Comment: 9 pages in revtex 4 style with 3 figures; minor revision with a change of title; to appear in PR

Morphologic and genetic characterisation of Corsican and Sardinian trout with comments on Salmo taxonomy

Both morphological and molecular data are presented and discussed for indigenous Salmo sp. from Corsica and Sardinia, here called Tyrrhenian trout. For comparison, morphological data obtained from museum specimens, including the Algerian S. macrostigma, are discussed in the light of recent and new molecular findings. In total, 29 measurements and 20 meristic characters were taken from each specimen. Out of the meristic characters, 12 were obtained by means of X-ray. One important morphometric character in the present study is the size of the head measured from premaxilla to posterior margin of preoperculum. This character was particularly stable in all Tyrrhenian trout, showing relatively large head compared to Atlantic trout and to S. macrostigma. On the contrary, other characters like body punctuations, black and white edges of fins, body depth or number of epurals in the caudal skeleton are quite polymorphic. In certain meristic characters, range of variation of Tyrrhenian trout even exceeds that of the extensive comparative material. Each trout has been genetically characterized. New haplotypes from Tyrrhenian trout were discovered, belonging to three mitochondrial lineages viz. Adriatic, marble and Mediterranean, however, Adriatic haplotypes are dominant. Comparing morphological and genetic data, observed morphology lacks any obvious correlation to mitochondrial lineages and it is concluded that Tyrrhenian trout show no particular affinity to S. macrostigma from Algeria

Organization of the Zone of Transition between the Pretectum and the Thalamus, with Emphasis on the Pretectothalamic Lamina

The zone of transition between the pretectum, derived from prosomere 1, and the thalamus, derived from prosomere 2, is structurally complex and its understanding has been hampered by cytoarchitectural and terminological confusion. Herein, using a battery of complementary morphological approaches, including cytoarchitecture, myeloarchitecture and the expression of molecular markers, we pinpoint the features or combination of features that best characterize each nucleus of the pretectothalamic transitional zone of the rat. Our results reveal useful morphological criteria to identify and delineate, with unprecedented precision, several [mostly auditory] nuclei of the posterior group of the thalamus, namely the pretectothalamic lamina (PTL; formerly known as the posterior limitans nucleus), the medial division of the medial geniculate body (MGBm), the suprageniculate nucleus (SG), and the ethmoid, posterior triangular and posterior nuclei of the thalamus. The PTL is a sparsely-celled and fiber rich flattened nucleus apposed to the lateral surface of the anterior pretectal nucleus (APT) that marks the border between the pretectum and the thalamus; this structure stains selectively with the Wisteria floribunda agglutinin (WFA), and is essentially immunonegative for the calcium binding protein parvalbumin (PV). The MGBm, located medial to the ventral division of the MGB (MGBv), can be unequivocally identified by the large size of many of its neurons, its dark immunostaining for PV, and its rather selective staining for WFA. The SG, which extends for a considerable caudorostral distance and deviates progressively from the MGB, is characterized by its peculiar cytoarchitecture, the paucity of myelinated fibers, and the conspicuous absence of staining for calretinin (CR); indeed, in many CR-stained sections, the SG stands out as a blank spot. Because most of these nuclei are small and show unique anatomical relationships, the information provided in this article will facilitate the interpretation of the results of experimental manipulations aimed at the auditory thalamus and improve the design of future investigations. Moreover, the previously neglected proximity between the MGBm and the caudal region of the scarcely known PTL raises the possibility that certain features or roles traditionally attributed to the MGBm may actually belong to the PTL

Multiple faces elicit augmented neural activity

How do our brains respond when we are being watched by a group of people? Despite the large volume of literature devoted to face processing, this question has received very little attention. Here we measured the effects on the face-sensitive N170 and other ERPs to viewing displays of one, two and three faces in two experiments. In Experiment 1, overall image brightness and contrast were adjusted to be constant, whereas in Experiment 2 local contrast and brightness of individual faces were not manipulated. A robust positive-negative-positive (P100-N170-P250) ERP complex and an additional late positive ERP, the P400, were elicited to all stimulus types. As the number of faces in the display increased, N170 amplitude increased for both stimulus sets, and latency increased in Experiment 2. P100 latency and P250 amplitude were affected by changes in overall brightness and contrast, but not by the number of faces in the display per se. In Experiment 1 when overall brightness and contrast were adjusted to be constant, later ERP (P250 and P400) latencies showed differences as a function of hemisphere. Hence, our data indicate that N170 increases its magnitude when multiple faces are seen, apparently impervious to basic low-level stimulus features including stimulus size. Outstanding questions remain regarding category-sensitive neural activity that is elicited to viewing multiple items of stimulus categories other than faces

Environmental variables, habitat discontinuity and life history shaping the genetic structure of Pomatoschistus marmoratus

Coastal lagoons are semi-isolated ecosystems exposed to wide fluctuations of environmental conditions and showing habitat fragmentation. These features may play an important role in separating species into different populations, even at small spatial scales. In this study, we evaluate the concordance between mitochondrial (previous published data) and nuclear data analyzing the genetic variability of Pomatoschistus marmoratus in five localities, inside and outside the Mar Menor coastal lagoon (SE Spain) using eight microsatellites. High genetic diversity and similar levels of allele richness were observed across all loci and localities, although significant genic and genotypic differentiation was found between populations inside and outside the lagoon. In contrast to the FST values obtained from previous mitochondrial DNA analyses (control region), the microsatellite data exhibited significant differentiation among samples inside the Mar Menor and between lagoonal and marine samples. This pattern was corroborated using Cavalli-Sforza genetic distances. The habitat fragmentation inside the coastal lagoon and among lagoon and marine localities could be acting as a barrier to gene flow and contributing to the observed genetic structure. Our results from generalized additive models point a significant link between extreme lagoonal environmental conditions (mainly maximum salinity) and P. marmoratus genetic composition. Thereby, these environmental features could be also acting on genetic structure of coastal lagoon populations of P. marmoratus favoring their genetic divergence. The mating strategy of P. marmoratus could be also influencing our results obtained from mitochondrial and nuclear DNA. Therefore, a special consideration must be done in the selection of the DNA markers depending on the reproductive strategy of the species

Reengineering the clinical research enterprise to involve more community clinicians

<p>Abstract</p> <p>Background</p> <p>The National Institutes of Health has called for expansion of practice-based research to improve the clinical research enterprise.</p> <p>Methods</p> <p>This paper presents a model for the reorganization of clinical research to foster long-term participation by community clinicians.</p> <p>Based on the literature and interviews with clinicians and other stakeholders, we posited a model, conducted further interviews to test the viability of the model, and further adapted it.</p> <p>Results</p> <p>We propose a three-dimensional system of checks and balances to support community clinicians using research support organizations, community outreach, a web-based registry of clinicians and studies, web-based training services, quality audits, and a feedback mechanism for clinicians engaged in research.</p> <p>Conclusions</p> <p>The proposed model is designed to offer a systemic mechanism to address current barriers that prevent clinicians from participation in research. Transparent mechanisms to guarantee the safety of patients and the integrity of the research enterprise paired with efficiencies and economies of scale are maintained by centralizing some of the functions. Assigning other responsibilities to more local levels assures flexibility with respect to the size of the clinician networks and the changing needs of researchers.</p

e-Pilly TROP Maladies infectieuses tropicales

L’e-Pilly TROP est un ouvrage d’infectiologie tropicale destiné aux médecins et aux étudiants en médecine des pays francophones du Sud. La prise en compte des différents niveaux de la pyramide sanitaire dans ces pays le rend aussi accessible aux infirmiers des centres de santé communautaires urbains et des structures de santé intermédiaires des zones rurales. Par définition, les Pays En Développement accroissant progressivement leurs capacités de diagnostic biologique et de traitement, les outils de prise en charge correspondent aux moyens des niveaux périphériques comme à ceux des niveaux hospitaliers de référence

How Terrorism Explains Capital Flight from Africa

We assess the effects of terrorism on capital flight in a panel of 29 African countries for which data is available for the period 1987-2008. The terrorism dynamics entail domestic, transnational, unclear and total terrorisms. The empirical evidence is based on Generalised Method of Moments (GMM) with forward orthogonal deviations and Quantile regressions (QR). The following findings are established. First, for GMM, domestic, unclear and total terrorisms consistently increase capital flight, with the magnitude relative higher from unclear terrorism. Second, for QR: (i) the effect of transnational terrorism is now positively significant in the top quantiles (0.75th and 0.90th) of the capital flight distribution, (ii) domestic and total terrorisms are also significant in the top quantiles and (iii) unclear terrorism is significant in the 0.10th and 0.75th quantiles. Policy implications are discussed