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When a reinforcement learning agent executes actions that can cause frequent damage to itself, it can learn, by using Q-learning, that these actions must not be executed again. However, there are other actions that do not cause damage frequently but only once in a while, for example, risky actions such as parachuting. These actions may imply punishment to the agent and, depending on its personality, it would be better to avoid them. Nevertheless, using the standard Q-learning algorithm, the agent is not able to learn to avoid them, because the result of these actions can be positive on average. In this article, an additional mechanism of Q-learning, inspired by the emotion of fear, is introduced in order to deal with those risky actions by considering the worst results. Moreover, there is a daring factor for adjusting the consideration of the risk. This mechanism is implemented on an autonomous agent living in a virtual environment. The results present the performance of the agent with different daring degrees. ; The funds provided by the Spanish Government through the project called "A New Approach to Social Robotics" (AROS), of MICINN (Ministry of Science and Innovation) and through the RoboCity2030-IICM project (S2009/DPI-1559), funded by Programas de Actividades I+D en la Comunidad de Madrid and cofunded by Structural Funds of the EU.

This review begins with a subject that is familiar to all urban historians of the Middle Ages. Citizenship was one of the most ubiquitous forms of social and political organization in medieval towns. Yet, as Pierre Racine points out, in 'La citoyenneté en Italie au Moyen Âge', Le Moyen Âge, 115 (2009), 87–108, it is perhaps surprising that there have been so few studies devoted specifically to the right of citizenship in the Italian cities of the communal period. Racine's discussion is focused upon the period between the eleventh and fourteenth centuries, that is, from the formation of the communes to the emergence of princely states in northern and central Italy, when many of the city-states disappeared. If citizenship was in some ways a burden which entailed liability to taxation and the fulfilment of military service, it was fundamentally a privilege. Thus, the thirteenth-century communal governments of cities such as Piacenza appointed officials charged with investigating cases of 'false citizens'. Citizenship was acquired largely on the basis of more or less permanent residence and the ownership of a house in the city and it allowed the citizen to participate in the popular assembly, where the important questions concerning the election of officials and the problems of daily life were debated and decided. In emphasizing the emotional attachment which citizens felt towards their urban patria, Racine addresses the cultural as well as juridical meaning of citizenship.

International audience ; In the traditional scientific publishing business, journals limit access to subscribers or sell articles on a pay per view basis. But they also request additional publication charges from authors. The total public cost amounts several thousand US dollars per paper. In this paper we studied innovative approaches offering to publish papers rapidly while accessing peer review and publishing discussion papers enabling interactive public discussion. In order to discuss those new possibilities, we took the example of the European Union of Geosciences journals. For those journals, one of the benefits of their interactive Open Access publishing was a positive evolution of their Impact Factor. We then reviewed the automated coverage of services charge as proposed by Copernicus and described its advantages for institutions. ; Dans les modèles traditionnels d'édition, l'accès aux revues est limité aux souscripteurs sur la base du "pay per view". Mais cela engendre aussi des frais de publication pour les auteurs. Le coût par article est d'environ 1000 US$ par article. Dans cet article nous décrivons de nouveaux modèles innovants de publication. Les articles sont publiés rapidement sous un mode de discussion, les commentaires sont en ligne et interactifs. L'exemple cité est celui de l'EGU (European Union of Geosciences journals). Ces revues ont un facteur d'impact qui augmente de manière beaucoup plus rapide. On verra ensuite le coût de ce nouveau mode de publication et l'avantage pour les organismes.

El pdf del artículo es el manuscrito de autor. ; Coadministration of entacapone with levodopa attenuates motor complications in experimental models of Parkinson's disease. The mechanisms underlying entacapone effects are unknown. We investigated the effect of entacapone, on: long-duration response (LDR) to levodopa, levodopa-induced postsynaptic pharmacodynamic mechanisms and molecular changes in hemiparkinsonian rats. 6-Hydroxydopamine-unilaterally lesioned rats were treated with levodopa (25 mg/kg) + vehicle; levodopa + entacapone (30 mg/kg) or saline, twice daily for 22 days. The LDR and the apomorphine-induced rotations were measured. In situ hybridization was performed measuring the expression of striatal preproenkephalin, preprodynorphin and dopamine D-3 receptor mRNAs, subthalamic cytochrome oxidase mRNA and nigral glutamic acid decarboxylase mRNA. Entacapone potentiated the LDR but did not modify either the apomorphine-induced rotational behavior or the molecular changes. Our results suggest that the effects of entacapone on levodopa-induced motor response are not mediated by postsynaptic mechanisms and that administration of entacapone is not able to normalize the molecular alterations induced by levodopa in the basal ganglia. ; This work was supported by an unrestricted grant from Novartis-Orion Pharma (Barcelona, Spain). JAO serves as external adviser for Novartis Pharmaceutical (Barcelona, Spain). EA is partially financed by the program: Ayudas para Contratos de Apoyo a la Investigación en el Sistema Nacional de Salud from the Ministerio de Sanidad y Consumo of the Spanish Government. ; Peer reviewed

Higher levels of girls and women's participation in targeted areas are widely apparent, particularly in affluent and middle‐class sites. Here, we report on research with young middle and upper middle‐class high school girls successfully enrolled in non‐traditional advanced placement (AP) courses in mathematics, science, and computer programming in a suburban school district in Midwestern USA. Focus group inter‐views with 45 of the highest achieving students in this affluent suburb revealed salient inequities and lingering impediments in the struggle for women's equality. Likewise, the limitations of gender equity politics are evident in the co‐ opting of discourse of privilege and individualism. Key words: girls' achievement, secondary schools, girls in advanced placement study, AP classes Une présence accrue des filles dans les cours avancés de mathématiques, de science et d'informatique au secondaire est manifeste, surtout dans les milieux aisés aux É.‐U. et dans d'autres pays occidentaux. Cette recherche quantitative, effectuée auprès de jeunes filles de classe moyenne ou supérieure inscrites dans des cours de niveau avancé de mathématiques, de science et d'informatique au secondaire dans un arrondissement scolaire du Midwest américain, révèle des inégalités importantes et des obstacles persistants dans la lutte des femmes pour une pleine égalité, ce qui montre les limites des politiques en faveur de l'équité entre les sexes. Mots clés : équité entre les sexes, filles et mathématiques avancées, cours de science, cours d'informatique, filles et science, cours de mathématiques

La descentralización de políticas sociales hacia los municipios es planteada como una alternativa de desarrollo a partir de las relaciones micro sociales. Los municipios deben asumir una nueva responsabilidad y plantearse una nueva función: definir y ejecutar políticas sociales locales o regionales. Esta nueva relación del municipio con su población ha sido uno de los elementos, en un proceso que tiene múltiples explicaciones, que ha favorecido nuevas prácticas clientelares denominadas Clientelismo fino o institucional. Este clientelismo favorece una situación de sometimiento y de asistencialismo, dificultando nuevas formas de relación que permitan el desarrollo humano y el ejercicio de derechos. ; The decentralization of social policies towards the local government, is considered as an alternative to development from the micro social relations. Local government now, must assume a new responsibility and consider a new Function: define and execute local or regional social policies. This new relation of the local govermmen with its population has been one of the elements in a process that has manifold explanations, that have favored new clientelistic practices called "subtle or institutional clientelism". This clientelism encourages a welfare dependency and a situation of powerlessness, making difficult new forms of relation that allow human development and the exercise of rights. ; Fil: Antón, Sofía. Universidad Nacional de Cuyo. Facultad de Ciencias Políticas y Sociales ; Fil: Sandes, Liliana. Universidad Nacional de Cuyo. Facultad de Ciencias Políticas y Sociales

AbstractThe shallow Training Lake in Jiangnan has received much attention in historical records because of the direct involvement of successive dynastic governments in the protection of its seasonal water supply to the Grand Canal. Historians have all praised the periodical efforts to restore the lake's water supply and irrigation functions. However, in view of the high operating costs of the lake and its limited benefits, the various attempts to reclaim land and water for agriculture may have been more rational in terms of economic profit. Visitors' descriptions provide many details on the long-term environmental changes in the lake area. In the 1960s, it was drained and turned into a state farm. Le Lac d'Entraînement peu profond de Jiangnan a retenu l'attention dans les textes historiques parce que les gouvernements dynastiques successifs se sont investis pour assurer alimentation saisonnier du Grand Canal par ses eaux. Tous les historiens ont loué les efforts périodiques visant à lui conserver sa fonction d'alimentation et d'irrigation. Parce que les frais d'entretien du lac étaient élevés et les profits limités, il se peut néanmoins que les travaux entrepris pour convertir le lac en terres agricoles étaient plus rentables. Les descriptions des visiteurs nous fournissent d'abondants détails sur les changements environnementaux à long terme que subit la région du Lac. Dans les années 1960, il fut drainé pour y installer une exploitation agricole d'état.

This article tries to explore the limits of the legal concepts related to the refugee world by moving from one camp to another in the north-east of Sudan. This spatial approach, in the form of descriptive 'travelling', is based on a back-to-back comparison between two exile territories. One is still recognised by the international community while the other is renamed as an existing entity. These two contradictory spaces are leading to the paradox of humanitarian aid. ; International audience ; This article tries to explore the limits of the legal concepts related to the refugee world by moving from one camp to another in the north-east of Sudan. This spatial approach, in the form of descriptive 'travelling', is based on a back-to-back comparison between two exile territories. One is still recognised by the international community while the other is renamed as an existing entity. These two contradictory spaces are leading to the paradox of humanitarian aid. ; Cet article tente d'explorer les limites des concepts juridiques liés au monde des réfugiés en passant d'un camp à l'autre dans le nord-est soudanais. Cette approche spatiale, sous forme de « travelling » descriptif, s 'appuie sur une comparaison mettant dos-à-dos deux territoires d'exil. L 'un est encore reconnu par la communauté internationale alors que l'autre est renié comme entité existante. Ces deux espaces contradictoires font émerger les paradoxes de l 'aide humanitaire.

AbstractThis paper examines the merger announcements of Canadian companies between 1994 and 2000 during an exceptional merger boom. The results show that both the target companies and the acquirer companies obtain significant positive abnormal returns during this time period. Companies that acquire private targets with stock have positive returns; however, acquirers of private firms have significantly higher risk compared with those that acquire public targets, despite nonsignificant differences in returns. Acquirers pay significantly less to acquire private firms than public firms, especially with stock. Overall, the findings suggest there is support for a liquidity discount for private firms, and the market is efficient in valuing firms in asymmetric conditions.RésuméDans cet article, nous examinons les annonces de fusions des compagnies canadiennes entre 1994 et 2000, période de grand boom de fusion. Les résultats montrent qu'au cours de cette période, les compagnies cibles et les compagnies acquéreuses obtiennent des rendements anormaux positifs. Les entreprises qui achètent des cibles privées avec des actions ont des rendements positifs; cependant, ces entreprises ont des risques considérablement plus élevés par rapport aux entreprises qui achètent des cibles publiques nonobstant des différences négligeables dans les rendements. Par ailleurs, les acquéreurs paient nettement moins pour acheter les entreprises privées que pour acheter les entreprises publiques, en particulier celles qui ont des actions. Dans l'ensemble, les résultats de l'étude révèlent qu'il est nécessaire d'escompter la liquidité pour les entreprises privées et que le marché permet de valoriser les entreprises dans les conditions asymétriques.

This study examined group knowledge in three school boards, which we conceptualised as a phenomenon influenced by structural/political and social/relational elements and composed of affective, axiological, and cognitive dimensions. Several data collection techniques were used: surveys, conversation analysis, observation, and the Critical Decision Method (CDM). Results indicate that group knowledge is strongly influenced by group communication patterns and the structural and political environment. Most importantly, the results suggests that the affective, axiological, and cognitive dimensions of group knowledge are not discrete, but interact with each other within the processes of knowledge transformation and knowledge transfer Key words: educational governance, decision‐making, emotion, cognition, values L'étude porte sur les connaissances du groupe au sein de trois conseils scolaires. D'après les auteurs, il s'agit d'un phénomène influencé par des éléments structurels/politiques et sociaux/relationnels et regroupant des dimensions affective, axiologique et cognitive. Plusieurs techniques de collecte de données ont été utilisées : sondages, analyse de conversations, observations et la Critical Decision Method (CDM). Les résultats indiquent que les connaissances du groupe sont fortement influencées par les méthodes de communication dans le groupe et le contexte structurel et politique. Ces résultats semblent surtout indiquer que les dimensions affective, axiologique et cognitive des connaissances du groupe ne sont pas discrètes, mais qu'elles s'influencent mutuellement au sein du processus de transformation et de transfert des connaissances. Mots clés : gouvernance en éducation, prise de décisions, émotion, cognition, valeurs.

11 páginas, 12 figuras.-- Trabajo presentado en la conferencia "Bioengineered and Bioinspired Systems II"; Sevilla (España); 09-Mayo-2005; Editores: Ricardo A. Carmona, Gustavo Linan-Cembrano. ; This paper describes the fabrication, packaging and characterization of novel multilayer polymer microfluidic systems fabricated by a CMOS compatible process. These microfluidic devices were specially designed for BioMOEMS applications. Embedded multilayer rectangular smooth and uniform microchannels, 50 to 150 mm wide and 18mm deep were studied. Steady-state flow rates and pressure driven flow control were measured in the laminar flow regime. Flow rates ranging from 1 to 100 µl/min, at pressure drop ranging from 10 to 600 kPa, were obtained. These flow rates yield Reynolds numbers (Re) up to 20. Results indicate that the experimental Re and the flow friction coefficient (f) are in good agreement with the laminar flow theory. These experimental results facilitate the future designs of different microfluidic devices designed by using classical fluidic theory. We also present two different methods developed for macro/microfluidic packaging in order to connect these microfluidic devices to the macroscopic world. The microsystem packaging can withstand pressure drops up from 500 to 2000 kPa with any liquid leakage. ; This research is sponsored by the Basque and Spanish Governments, under the Torres Quevedo Spanish Fellowship for industrial research and the strategic research program on micro and nanotechnologies (MICROGUNE). ; Peer reviewed

9 páginas, 9 figuras, 1 tabla. ; Spatial patterns of the urban heat island (UHI) in Zaragoza (Spain) were determined by Principal Component Analysis (VARIMAX rotation) of air temperature in the city, and mapped using GIS. The 3 components extracted accounted for 92.9% of the total variance. Principal component (PC) 1 accounted for the most general patterns of UHI, PC2 showed a shift of warm areas to the SE and PC3 a shift to the NW. A rotated component matrix was used to identify correlations between each component and daily maps. The spatial patterns indicated by PC2 and PC3 were determined by surface wind direction. The displacement of warm areas to the SE (PC2) was greater during NW winds while the shift to the NW (PC3) was produced mainly by SE winds. ; We acknowledge financial support from the following projects: BSO2002-02743, REN2003-07453, CGL2005-0408/BOS (funded by the Ministerio de Ciencia y Tecnología of Spain, and by FEDER); 'Programa de grupos de investigación consolidados', grupo Clima, Cambio Global y Sistemas Naturales, BOA 48 of 20-04-2005 (funded by the Government of Aragon); and 'Clima y calidad ambiental en la ciudad de Zaragoza' (funded by the Zaragoza City Council). Research of S.M.V.-S. was supported by a postdoctoral fellowship of the Ministerio de Educación, Cultura y Deporte of Spain). ; Peer reviewed

AbstractTraditional scale purification methods and IRT analyses are applied to a Chinese version of the short Need for Cognition scale (18 items). Traditional methods indicate that the scale contains one clear dominant factor (α = 0.822). Nevertheless, it is also indicated that the composite contains poor items, which should perhaps be deleted from the scale. This is made particularly evident by the presence of low factor loadings. On the other hand, IRT analyses identify anomalies with individual scale items that are not made apparent with traditional methods. In particular, some items do not tend to discriminate well between individuals who score highly or poorly on Need for Cognition.RésuméLes méthodes traditionnelles d'épuration ainsi qu'une approche basée sur le fonctionnement différentiel de l'ltem (FDI) sont comparées lors de l'analyse psychométrique d'une version chinoise de l'échelle de l'intensité du raisonnement cognitif réduite à 18 items. D'une part, les résultats rapportés par l'approche traditionnelle démontrent qu'un facteur dominant est clairement identifié (α = 0.822). Néanmoins, le composé qui en résulte renferme des items ayant des saturations relativement faibles. Ceci indique done que certains de ces items devraient être potentiellement éliminés. D'autre part, l'analyse FDI révèle des faiblesses de certains items de cette échelle non décelables par les procédures traditionnelles. Parmi ces faiblesses, nous pouvons citer la capacité discriminatoire réduite entre des individus présentant unfaible ou un grand niveau de l'intensité du raisonnement cognitif.

In this paper we compare the orthodox optimal tariff formula with the appropriate welfare–maximizing tariff when there are a few producing or importing firms. The welfare–maximizing tariff can be very low, voire negative in some cases, while in others it can even exceed the maximum–revenue tariff. The relationship between the welfare–maximizing tariff and the number of firms need not be monotonically increasing, because the tariff is not strictly used to internalize terms of trade externality. It is also used to manipulate cost asymmetries between producing and importing firms. Welfare–maximizing specific tariffs are never worse than their ad valorem counterparts. JEL Classification F13, L13 Tarif qui maximise le bien être et tarif qui maximise le revenu quand on est en présence de peu de firmes. Nous comparons le tarif optimal orthodoxe au tarif maximisant le bien être lorsqu'il y a peu de firmes productrices ou importatrices. Le tarif qui maximise le bien être est parfois très bas, même négatif, mais il peut excéder le tarif qui maximise le revenu dans d'autres cas. La relation entre le tarif et le nombre de firmes n'est pas nécessairement monotone parce que le tarif n'est pas strictement utilisé pour améliorer les termes d'échange. Il est aussi utilisé pour manipuler les asymétries dans les coûts des firmes productrices et importatrices. Le tarif spécifique n'est jamais dominé par le tarif ad valorem.

Copyright © by National Academy of Sciences. La versión original está disponible en http://www.pnas.org/ ; Buchnera aphidicola is an obligate, strictly vertically transmitted, bacterial symbiont of aphids. It supplies its host with essential amino acids, nutrients required by aphids but deficient in their diet of plant phloem sap. Several lineages of Buchnera show adaptation to their nutritional role in the form of plasmid-mediated amplification of key-genes involved in the biosynthesis of tryptophan (trpEG) and leucine (leuABCD). Phylogenetic analyses of these plasmid-encoded functions have thus far suggested the absence of horizontal plasmid exchange among lineages of Buchnera. Here, we describe three new Buchnera plasmids, obtained from species of the aphid host families Lachnidae and Pemphigidae. All three plasmids belong to the repA1 family of Buchnera plasmids, which is characterized by the presence of a repA1-replicon responsible for replication initiation. A comprehensive analysis of this family of plasmids unexpectedly revealed significantly incongruent phylogenies for different plasmid and chromosomally encoded loci. We infer from these incongruencies a case of horizontal plasmid transfer in Buchnera. This process may have been mediated by secondary endosymbionts, which occasionally undergo horizontal transmission in aphids. ; This work was supported by an European Union Human Capital Mobility research grant (CHRX-CT94–0660 to R.V.H.) and Grant PB96–0793 C0401 from Dirección General de Ensenanza Superior (to A.M.). ; Peer reviewed