1,173 research outputs found

    Adolescent D-amphetamine treatment in a rodent model of attention deficit/hyperactivity disorder: impact on cocaine abuse vulnerability in adulthood

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    RATIONALE: Stimulant medications for attention-deficit/hyperactivity disorder (ADHD) in adolescents remain controversial with respect to later development of cocaine abuse. Past research demonstrated that adolescent methylphenidate treatment increased several aspects of cocaine self-administration during adulthood using the spontaneously hypertensive rat (SHR) model of ADHD. Presently, we determined effects of the alternate stimulant medication, d-amphetamine, on cocaine self-administration. OBJECTIVES: We tested the hypothesis that adolescent d-amphetamine would not increase cocaine self-administration in adult SHR, given that d-amphetamine has a different mechanism of action than methylphenidate. METHODS: A pharmacologically relevant dose of d-amphetamine (0.5 mg/kg) or vehicle was administered throughout adolescence to SHR and two control strains, Wistar-Kyoto (WKY) and Wistar (WIS). Three aspects of cocaine abuse vulnerability were assessed in adulthood after discontinuing adolescent treatments: acquisition rate and dose-related responding under fixed (FR) and progressive (PR) ratio schedules. RESULTS: Adult SHR acquired cocaine self-administration faster and self-administered more cocaine across multiple doses compared to WKY and WIS under FR and PR schedules, indicating that SHR is a reliable animal model of comorbid ADHD and cocaine abuse. Relative to vehicle, SHR and WIS with adolescent d-amphetamine treatment self-administered less cocaine upon reaching acquisition criteria, and WIS additionally acquired cocaine self-administration more slowly and had downward shifts in FR and PR cocaine dose-response curves. WKY with adolescent d-amphetamine treatment acquired cocaine self-administration more quickly relative to vehicle. CONCLUSIONS: In contrast to methylphenidate, adolescent d-amphetamine did not augment cocaine self-administration in SHR. Adolescent d-amphetamine treatment actually protected against cocaine abuse vulnerability in adult SHR and WIS.National Institutes of Health grant DA011716 and the Clara Mayo Memorial Fellowship at Boston University. (DA011716 - National Institutes of Health; Clara Mayo Memorial Fellowship at Boston University)https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5026317/Published versio

    Leading edge vortex dynamics on a pitching delta wing

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    The leading edge flow structure was investigated on a 70 deg flat plate delta wing which was pitched about its 1/2 chord position, to increase understanding of the high angle of attack aerodynamics on an unsteady delta wing. The wing was sinusoidally pitched at reduced frequencies ranging from k being identical with 2pi fc/u = 0.05 to 0.30 at chord Reynolds numbers between 90,000 and 350,000, for angle of attack ranges of alpha = 29 to 39 deg and alpha = 0 to 45 deg. The wing was also impulsively pitched at an approximate rate of 0.7 rad/s. During these dynamic motions, visualization of the leading edge vorticies was obtained by entraining titanium tetrachloride into the flow at the model apex. The location of vortex breakdown was recorded using 16mm high speed motion picture photography. When the wing was sinusoidally pitched, a hysteresis was observed in the location of breakdown position. This hysteresis increased with reduced frequency. The velocity of breakdown propagation along the wing, and the phase lag between model motion and breakdown location were also determined. When the wing was impulsively pitched, several convective times were required for the vortex flow to reach a steady state. Detailed information was also obtained on the oscillation of breakdown position in both static and dynamic cases

    Élevage porcin et santé publique : risque, controverse et violence non intentionnelle

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    Au Québec comme ailleurs, l’élevage porcin, considéré comme risqué par plusieurs, suscite questionnements et controverse. Des incertitudes scientifiques demeurent quant à ses effets sur la santé. D’où notre intention d’aborder, dans cet article, la question de l’influence de l’élevage porcin sur la santé psychologique et sociale. Une recension systématique a permis d’évaluer la pertinence et la qualité de la documentation scientifique à ce sujet. Les résultats montrent une association entre des effets sur la qualité de vie et ce type de production animale. En effet, la ferme porcine augmenterait la controverse et les clivages sociaux, et elle affecterait le sentiment d’appartenance à la communauté et au milieu. Elle constitue à ce titre un risque à la santé. Peut-on en l’occurrence parler de violence et, si oui, comment pourrait-on la prévenir ?As is the case in other provinces, swine production in Quebec, considered by many to be fraught with risk, raise questions and spark controversy. The scientific community is still uncertain about its repercussions, especially its effects on public health. Our purpose in this article is therefore to examine the psychological and social impact of swine production. A systematic survey was carried out to assess the quality and appropriateness of scientific literature on the subject. Aggregated results show that there is a link between living standards and this type of animal production. The issue of pig farms apparently stokes controversy and social division, while exerting a negative influence on the individual’s sense of belonging to a community and a specific social background. Pig farms therefore constitute a threat to human well-being and as such, they constitute a form of violence. The question is how to prevent it

    Modélisation des déperditions énergétiques dans une serre de verre chauffée par rayonnement infrarouge et influence d'un écran thermique

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    Le but de ce projet consiste à modéliser les pertes énergétiques d'une serre en considérant les flux radiatifs des sources d'énergie et l'utilisation d'un écran thermique. Le modèle devait permettre l'évaluation d'un système de chauffage radiant électrique et déterminer l'influence de l'écran thermique avec celui-ci. Le modèle simule les pertes énergétiques de la serre avec un système de chauffage radiant et à l'eau chaude, avec et sans écran thermique. Des mesures expérimentales ont permis de calibrer et de valider le modèle. Avec la même température de végétation, le système de chauffage radiant procure des économies d'énergie de -0,2 à 2,6% par rapport au système à l'eau chaude. L'écran thermique réduit la consommation énergétique de la serre de 25,2 à 32,4% avec le système radiant et de 24,0 à 31,2% avec celui à l'eau chaude. Les performances du système radiant ne permettent pas de le recommander pour chauffer une serre. Par contre, l'écran thermique est un équipement efficace pour réduire les pertes énergétiques d'une serre

    Tracking advanced persistent threats in critical infrastructures through opinion dynamics

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    Advanced persistent threats pose a serious issue for modern industrial environments, due to their targeted and complex attack vectors that are difficult to detect. This is especially severe in critical infrastructures that are accelerating the integration of IT technologies. It is then essential to further develop effective monitoring and response systems that ensure the continuity of business to face the arising set of cyber-security threats. In this paper, we study the practical applicability of a novel technique based on opinion dynamics, that permits to trace the attack throughout all its stages along the network by correlating different anomalies measured over time, thereby taking the persistence of threats and the criticality of resources into consideration. The resulting information is of essential importance to monitor the overall health of the control system and cor- respondingly deploy accurate response procedures. Advanced Persistent Threat Detection Traceability Opinion Dynamics.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Developmental Dyslexia: Evidence for a Subgroup with a Reversal of Cerebral Asymmetry

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    The Computerized Brain Tomograms of 24 Patients with Developmental Dyslexia Were Analyzed for Cerebral Asymmetry. Ten Patients Showed a Reversal of the Pattern of Asymmetry Regularly Observed in Normal Right-Handed Individuals So that the Right Parietooccipital Region Was Wider Than the Left. the Ten Dyslexic Patients with This Reversal of Cerebral Asymmetry Had a Lower Mean Verbal IQ Than the Other 14 Dyslexic Patients in This Study. the Reversal of Cerebral Asymmetry that Occurred in Ten of the Dyslexic Patients May Result in Language Lateralization to a Cerebral Hemisphere that is Structurally Less Suited to Support Language Function and Thus Act as a Risk Factor for the Development of Reading Disability. © 1978, American Medical Association. All Rights Reserved

    Biofuels Production from Biomass by Thermochemical Conversion Technologies

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    Agricultural biomass as an energy resource has several environmental and economical advantages and has potential to substantially contribute to present days’ fuel demands. Currently, thermochemical processes for agricultural biomass to energy transformation seem promising and feasible. The relative advantage of thermochemical conversion over others is due to higher productivity and compatibility with existing infrastructure facilities. However, the majority of these processes are still under development phase and trying to secure a market share due to various challenges, right from suitable infrastructure, raw material, technical limitations, government policies, and social acceptance. The knowledge at hand suggests that biomass can become a sustainable and major contributor to the current energy demands, if research and development are encouraged in the field of thermochemical conversion for various agricultural biomass types. This paper intends to explore the physical and chemical characteristics of biofuel substitutes of fossil fuels, potential biomass sources, and process parameters for thermochemical conversion

    Electroconvulsive Therapy Increases Plasma Levels of Interleukin-6 a

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74956/1/j.1749-6632.1990.tb40529.x.pd
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