998 resultados para Catalytic Behavior
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In this paper we present a model of representative behavior in the dictator game. Individuals have simultaneous and non-contradictory preferences over monetary payoffs, altruistic actions and equity concerns. We require that these behaviors must be aggregated and founded in principles of representativeness and empathy. The model results match closely the observed mean split and replicate other empirical regularities (for instance, higher stakes reduce the willingness to give). In addition, we connect representative behavior with an allocation rule built on psychological and behavioral arguments. An approach consistently neglected in this literature. Key words: Dictator Game, Behavioral Allocation Rules, Altruism, Equity Concerns, Empathy, Self-interest JEL classification: C91, D03, D63, D74.
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The water consumption and the crop coefficient of the banana cv. Pacovan were estimated in Petrolina County, northeastern Brazil, in order to establish guidelines to irrigation water management. Evaluations were carried out since planting in January 1999 to the 3rd harvest in September 2001 on a microsprinkler irrigated orchard, with plants spaced in a 3 x 3 m grid. Average daily water consumption was 3.9, 4.0, and 3.3 mm in the 1st, 2nd and 3rd growing seasons, respectively. Crop coefficient values increased from 0.7 (vegetative growth) to 1.1 (flowering). Even with high soil water availability, transpiration was reduced due to high evaporative demand.
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Using numerical simulations we investigate how overall dimensions of random knots scale with their length. We demonstrate that when closed non-self-avoiding random trajectories are divided into groups consisting of individual knot types, then each such group shows the scaling exponent of approximately 0.588 that is typical for self-avoiding walks. However, when all generated knots are grouped together, their scaling exponent becomes equal to 0.5 (as in non-self-avoiding random walks). We explain here this apparent paradox. We introduce the notion of the equilibrium length of individual types of knots and show its correlation with the length of ideal geometric representations of knots. We also demonstrate that overall dimensions of random knots with a given chain length follow the same order as dimensions of ideal geometric representations of knots.
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We present ACACIA, an agent-based program implemented in Java StarLogo 2.0 that simulates a two-dimensional microworld populated by agents, obstacles and goals. Our program simulates how agents can reach long-term goals by following sensorial-motor couplings (SMCs) that control how the agents interact with their environment and other agents through a process of local categorization. Thus, while acting in accordance with this set of SMCs, the agents reach their goals through the emergence of global behaviors. This agent-based simulation program would allow us to understand some psychological processes such as planning behavior from the point of view that the complexity of these processes is the result of agent-environment interaction.
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We propose a simple rheological model to describe the thixotropic behavior of paints, since the classical hysteresis area, which is usually used, is not enough to evaluate thixotropy. The model is based on the assumption that viscosity is a direct measure of the structural level of the paint. The model depends on two equations: the Cross-Carreau equation to describe the equilibrium viscosity and a second order kinetic equation to express the time dependence of viscosity. Two characteristic thixotropic times are differentiated: one for the net structure breakdown, which is defined as a power law function of shear rate, and an other for the net structure buildup, which is not dependent on the shear rate. The knowledge of both kinetic processes can be used to improve the quality and applicability of paints. Five representative commercial protective marine paints are tested. They are based on chlorinated rubber, acrylic, alkyd, vinyl, and epoxy resins. The temperature dependence of the rheological behavior is also studied with the temperature ranging from 5 ºC to 35 ºC. It is found that the paints exhibit both shear thinning and thixotropic behavior. The model fits satisfactorily the thixotropy of the studied paints. It is also able to predict the thixotropy dependence on temperature. Both viscosity and the degree of thixotropy increase as the temperature decreases.
Resumo:
The contribution of the propagating and the evanescent waves associated with freely propagating non-paraxial light fields whose transverse component is azimuthally polarized at some plane is investigated. Analytic expressions are derived for describing both the spatial shape and the relative weight of the propagating and the evanescent components integrated over the transverse plane. The analysis is carried out within the framework of the plane-wave angular spectrum approach. These results are used to illustrate the behavior of a kind of donut-like beams with transverse azimuthal polarization at some plane.
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Plusieurs études suggèrent que les patients qui présentent un premier épisode psychotique et un passé délictueux présenteraient une clinique spécifique et nécessiteraient une prise en charge adaptée. A partir d'une cohorte de patients suivis pour un premier épisode psychotique dans la région de Melbourne {The Early Psychosis Prevention and Intervention Centre), nous avons analysé la prévalence d'actes délictueux dans leur passé (1), les caractéristiques cliniques à leur admission (2), l'évolution à court terme des patients ayant commis des délits par rapport aux autres patients (3). Nous avons également cherché à déterminer si des délits plus graves (atteinte à l'intégrité d'une personne) étaient corrélés à des caractéristiques cliniques particulières. Sur les 649 patients dont les données ont pu être analysées entre 1998 et 2000, 29% avaient un passé délictueux. Ils étaient en majorité des hommes et présentaient des difficultés sociales et scolaires plus importantes que les autres patients. Ils avaient également recours de manière plus régulière à des substances illicites et commis plus souvent des tentatives de suicide. Le tableau clinique qu'ils présentaient à leur admission dans le programme de soins était plus complexe et l'évolution globalement plus défavorable après 18 mois de traitement. Nous avons relevé aussi que la durée de psychose non traitée était plus longue que celle des autres patients. Enfin, les délits avec atteinte à l'intégrité d'une autre personne étaient plus fréquents en présence d'un insight faible et nécessitaient un plus grand nombre d'hospitalisation. Ces résultats confirment le besoin d'une recherche approfondie dans ce champ de la clinique et de stratégies de prévention et de soins plus spécifiques. Une détection précoce chez les jeunes hommes qui commettent des actes délictueux serait particulièrement importante puisque notre étude suggère que certains d'entre eux seraient dans une phase débutante et non reconnue d'un épisode psychotique. Une intervention plus rapide et adaptée pourrait avoir des conséquences positives à plusieurs niveaux.
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Työn tavoite oli kehittää karakterisointimenetelmät kalkkikiven ja polttoaineen tuhkan jauhautumisen ennustamiselle kiertoleijukattilan tulipesässä. Kiintoainekäyttäytymisen karakterisoinnilla ja mallintamisella voidaan tarkentaa tulipesän lämmönsiirron ja tuhkajaon ennustamista. Osittain kokeelliset karakterisointimenetelmät perustuvat kalkkikiven jauhautumiseen laboratoriokokoluokan leijutetussa kvartsiputkireaktorissa ja tuhkan jauhatumiseen rotaatiomyllyssä. Karakterisointimenetelmät ottavat huomioon eri-laiset toimintaolosuhteet kaupallisen kokoluokan kiertoleijukattiloissa. Menetelmät kelpoistettiin kaupallisen kokoluokan kiertoleijukattiloista mitattujen ja fraktioittaisella kiintoainemallilla mallinnettujen taseiden avulla. Kelpoistamistaseiden vähäisyydestä huolimatta karakterisointimenetelmät arvioitiin virhetarkastelujen perusteella järkeviksi. Karakterisointimenetelmien kehittämistä ja tarkentamista tullaan jatkamaan.
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Little is known about how genetic and environmental factors contribute to the association between parental negativity and behavior problems from early childhood to adolescence. The current study fitted a cross-lagged model in a sample consisting of 4,075 twin pairs to explore (a) the role of genetic and environmental factors in the relationship between parental negativity and behavior problems from age 4 to age 12, (b) whether parent-driven and child-driven processes independently explain the association, and (c) whether there are sex differences in this relationship. Both phenotypes showed substantial genetic influence at both ages. The concurrent overlap between them was mainly accounted for by genetic factors. Causal pathways representing stability of the phenotypes and parent-driven and child-driven effects significantly and independently account for the association. Significant but slight differences were found between males and females for parent-driven effects. These results were highly similar when general cognitive ability was added as a covariate. In summary, the longitudinal association between parental negativity and behavior problems seems to be bidirectional and mainly accounted for by genetic factors. Furthermore, child-driven effects were mainly genetically mediated, and parent-driven effects were a function of both genetic and shared-environmental factors.
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Recent reports point out the importance of the complex GK-GKRP in controlling glucose and lipid homeostasis. Several GK mutations affect GKRP binding, resulting in permanent activation of the enzyme. We hypothesize that hepatic overexpression of a mutated form of GK, GKA456V, described in a patient with persistent hyperinsulinemic hypoglycemia of infancy (PHHI) and could provide a model to study the consequences of GK-GKRP deregulation in vivo. GKA456V was overexpressed in the liver of streptozotocin diabetic mice. Metabolite profiling in serum and liver extracts, together with changes in key components of glucose and lipid homeostasis, were analyzed and compared to GK wild-type transfected livers. Cell compartmentalization of the mutant but not the wild-type GK was clearly affected in vivo, demonstrating impaired GKRP regulation. GKA456V overexpression markedly reduced blood glucose in the absence of dyslipidemia, in contrast to wild-type GK-overexpressing mice. Evidence in glucose utilization did not correlate with increased glycogen nor lactate levels in the liver. PEPCK mRNA was not affected, whereas the mRNA for the catalytic subunit of glucose-6-phosphatase was upregulated ~4 folds in the liver of GKA456V-treated animals, suggesting that glucose cycling was stimulated. Our results provide new insights into the complex GK regulatory network and validate liver-specific GK activation as a strategy for diabetes therapy.
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Tämä työ on tehty yhteistyössä kansainvälisen metsäteollisuusyrityksen Stora Enson kanssa. Työ on osa Stora Enson strategiaa kehitettäessä uusia ja innovatiivisia pakkausmateriaaleja ja ratkaisuja joustopakkausmarkkinoille. Työn päätavoitteina oli selvittää, millaisia odotuksia tuotemerkkienomistajilla ja jatkojalostajilla on joustopakkauksista ja kuinka pakkausten ostopäätökset syntyvät monitahoisessa liikeympäristössä. Työn teoreettinen viitekehys jaettiin kahteen osaan. Asiakasodotuksia lähestyttiin tutkimalla eri palvelu- ja tuotelaadun ulottuvuuksia, ja teollisuuden ostokäyttäytymistä tutkittiin organisaatioiden ostokäyttämistä kuvaavien mallien avulla. Työn empiirisessä osuudessa käytettiin laadullista tutkimusmenetelmää käsittäen asiakashaastatteluja lähinnä Yhdysvalloissa. Haastateltavat yritykset koostuivat maailman johtavista kuluttajatuotteita valmistavista yrityksistä sekä jatkojalostajista. Tutkimustulosten mukaan odotukset pakkauksista liittyvät lähinnä tuotteen suojaamiseen sekä myynnin edistämiseen. Pääodotuksina on myös saada mahdollisimman edullisia papereita, mahdollisimman hyvillä barrier- ja paino-ominaisuuksilla. Tutkimustulokset osoittavat myös, että paperiyhtiöt ovat epäonnistuneet tekemään itseään tunnetuksi teollisuudelle ja heidän odotetaan olevan tulevaisuudessa aggressiivisempia ja innovatiivisempia. Tuotemerkkienomistajat ostavat pakkaukset ja pakkausmateriaalit normaalisti mieluiten jatkojalostajiensa kautta, mutta silti he toivovat yhteistyötä paperintoimittajien kanssa kunhan vain myös jatkojalostajat sisällytetään toimintaan mukaan.
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BACKGROUND: Lack of donor organs remains a major obstacle in organ transplantation. Our aim was to evaluate (1) the association between engaging in high-risk recreational activities and attitudes toward organ donation and (2) the degree of reciprocity between organ acceptance and donation willingness in young men. METHODS: A 17-item, close-ended survey was offered to male conscripts ages 18 to 26 years in all Swiss military conscription centers. Predictors of organ donation attitudes were assessed in bivariate analyses and multiple logistic regression. Reciprocity of the intentions to accept and to donate organs was assessed by means of donor card status. RESULTS: In 1559 responses analyzed, neither motorcycling nor practicing extreme sports reached significant association with donor card holder status. Family communication about organ donation, student, or academic profession and living in a Latin linguistic region were predictors of positive organ donation attitudes, whereas residence in a German-speaking region and practicing any religion predicted reluctance. Significantly more respondents were willing to accept than to donate organs, especially among those without family communication concerning organ donation. CONCLUSIONS: For the first time, it was shown that high-risk recreational activities do not influence organ donation attitudes. Second, a considerable discrepancy in organ donation reciprocity was identified. We propose that increasing this reciprocity could eventually increase organ donation rates.
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The question of whether symbolically mediated behavior is exclusive to modern humans or shared with anatomically archaic populations such as the Neandertals is hotly debated. At the Grotte du Renne, Arcy-sur-Cure, France, the Châtelperronian levels contain Neandertal remains and large numbers of personal ornaments, decorated bone tools and colorants, but it has been suggested that this association reflects intrusion of the symbolic artifacts from the overlying Protoaurignacian and/or of the Neandertal remains from the underlying Mousterian.
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En este trabajo se presenta un estudio químico y estructural de las capas metálicas de Pt y TaSix utilizadas como puerta catalítica en sensores de gas de alta temperatura basados en dispositivos MOS de SiC. Para ello se han depositado capas de diferentes espesores sobre substratos de Si. Los resultados muestran que con la reducción del espesor de Pt y con un recocido se consigue aumentar la rugosidad de las capas de puerta, lo que debería aumentar la sensibilidad y la velocidad de respuesta de los dispositivos que las incorporasen. Otro efecto del recocido es la transformación química del material de la puerta que, para capas delgadas de Pt con TaSix, produce la transformación total Pt en Pt2Ta, lo que podría afectar a las características catalíticas de la puerta. Los primeros resultados eléctricos indican que, a pesar de que las capas de Pt empleadas son gruesas y compactas, los diodos MOS túnel de SiC son sensibles a los gases CO y NO2, aunque presentan una velocidad de respuesta bastante lenta.