2,075 research outputs found

    Student Press Law: Past, Present, and Future

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    This dissertation will identify and describe the state of the law regarding student speech and press freedom. The following questions will be explored: What rights do young people have? What standards have state and federal courts established? To what extent and how clearly have state statutes defined student expressive rights? What do state laws say about this topic? What issues have yet to be addressed, either because a case has not raised certain issues or because the issue does not lend itself to compromise or a clear solution? How does the capacity of social media for widespread and rapid dissemination affect the balancing of First Amendment rights with other interests? Among other topics, the dissertation will discuss the development of First Amendment law, the strengthening of student expression law in the 1960s, the curtailment of student expression rights at the K-12 level in the 1980s, and state legislation that protects student expression at the K-12 and university levels. The conclusion will contain strategies for the enhancement of studentsā€™ First Amendment rights

    The industrial pollution projection system

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    The World Bank's technical assistance work with new environmental protection institutions stresses cost-effective regulation, with market-based pollution control instruments implemented wherever feasible. But few environmental protection institutions can do the benefit-cost analysis needed because they lack data on industrial emissions and abatement costs. For the time being, they must use appropriate estimates. The industrial pollution projection system (IPPS) is being developed as a comprehensive response to this need for estimates. The estimation of IPPS parameters is providing a much clearer, more detailed view of the sources of industrial pollution. The IPPS has been developed to exploit the fact that industrial pollution is heavily affected by the scale of industrial activity, by its sectoral composition, and by the type of process technology used in production. Most developing countries have little or no data on industrial pollution, but many of them have relatively detailed industry-survey information on employment, value added, or output. The IPPS is designed to convert this information to a profile of associated pollutant output for countries, regions, urban areas, or proposed new projects. It operates through sectoral estimates of pollution intensity, or pollution per unit of activity. The IPPS is being developed in two phases. The first prototype has been estimated from a massive U.S. data base developed by the Bank's Policy Research Department, Environment, Infrastructure, and Agriculture Division, in collaboration with the Center for Economic Studies of the U.S. Census Bureau and the U.S. Environmental Protection Agency. This database was created by merging manufacturing census data with Environment Protection Agency data on air, water, and solid waste emissions. It draws on environmental, economic, and geographic information from about 200,000 U.S. factories. The IPPS covers about 1,500 product categories, all operating technologies, and hundreds of pollutants. It can project air, water, or solid waste emissions, and it incorporates a range of risk factors for human toxins and ecotoxic effects. The more ambitious second phase of IPPS development will take into account cross-country and cross-regional variations in relative prices, economic and sectoral policies, and strictness of regulation.Water and Industry,Environmental Economics&Policies,Public Health Promotion,Health Monitoring&Evaluation,Sanitation and Sewerage,Water and Industry,Environmental Economics&Policies,Health Monitoring&Evaluation,Sanitation and Sewerage,TF030632-DANISH CTF - FY05 (DAC PART COUNTRIES GNP PER CAPITA BELOW USD 2,500/AL

    Intercomparison of standard resolution and high resolution TOVS soundings with radiosonde, lidar, and surface temperature/humidity data

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    One objective of the FIRE Cirrus IFO is to characterize relationships between cloud properties inferred from satellite observations at various scales to those obtained directly or inferred from very high resolution measurements. Satellite derived NOAA-9 high and standard resolution Tiros Operational Vertical Sounder (TOVS) soundings are compared with directly measured lidar, surface temperature, humidity, and vertical radiosonde profiles associated with the Ft. McCoy site. The results of this intercomparison should be useful in planning future cloud experiments

    Corticosterone Acts in the Nucleus Accumbens to Enhance Dopamine Signaling and Potentiate Reinstatement of Cocaine Seeking

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    Stressful life events are important contributors to relapse in recovering cocaine addicts, but the mechanisms by which they influence motivational systems are poorly understood. Studies suggest that stress may ā€œset the stageā€ for relapse by increasing the sensitivity of brain reward circuits to drug-associated stimuli. We examined the effects of stress and corticosterone on behavioral and neurochemical responses of rats to a cocaine prime after cocaine self-administration and extinction. Exposure of rats to acute electric footshock stress did not by itself reinstate drug-seeking behavior but potentiated reinstatement in response to a subthreshold dose of cocaine. This effect of stress was not observed in adrenalectomized animals, and was reproduced in nonstressed animals by administration of corticosterone at a dose that reproduced stress-induced plasma levels. Pretreatment with the glucocorticoid receptor antagonist RU38486 did not block the corticosterone effect. Corticosterone potentiated cocaine-induced increases in extracellular dopamine in the nucleus accumbens (NAc), and pharmacological blockade of NAc dopamine receptors blocked corticosterone-induced potentiation of reinstatement. Intra-accumbens administration of corticosterone reproduced the behavioral effects of stress and systemic corticosterone. Corticosterone treatment acutely decreased NAc dopamine clearance measured by fast-scan cyclic voltammetry, suggesting that inhibition of uptake2-mediated dopamine clearance may underlie corticosterone effects. Consistent with this hypothesis, intra-accumbens administration of the uptake2 inhibitor normetanephrine potentiated cocaine-induced reinstatement. Expression of organic cation transporter 3, a corticosterone-sensitive uptake2 transporter, was detected on NAc neurons. These findings reveal a novel mechanism by which stress hormones can rapidly regulate dopamine signaling and contribute to the impact of stress on drug intake

    Corticosterone Regulates Both Naturally Occurring and Cocaineā€Induced Dopamine Signaling by Selectively Decreasing Dopamine Uptake

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    Stressful and aversive events promote maladaptive rewardā€seeking behaviors such as drug addiction by acting, in part, on the mesolimbic dopamine system. Using animal models, data from our laboratory and others show that stress and cocaine can interact to produce a synergistic effect on reward circuitry. This effect is also observed when the stress hormone corticosterone is administered directly into the nucleus accumbens (NAc), indicating that glucocorticoids act locally in dopamine terminal regions to enhance cocaine\u27s effects on dopamine signaling. However, prior studies in behaving animals have not provided mechanistic insight. Using fastā€scan cyclic voltammetry, we examined the effect of systemic corticosterone on spontaneous dopamine release events (transients) in the NAc core and shell in behaving rats. A physiologically relevant systemic injection of corticosterone (2 mg/kg i.p.) induced an increase in dopamine transient amplitude and duration (both voltammetric measures sensitive to decreases in dopamine clearance), but had no effect on the frequency of transient release events. This effect was compounded by cocaine (2.5 mg/kg i.p.). However, a second experiment indicated that the same injection of corticosterone had no detectable effect on the dopaminergic encoding of a palatable natural reward (saccharin). Taken together, these results suggest that corticosterone interferes with naturally occurring dopamine uptake locally, and this effect is a critical determinant of dopamine concentration specifically in situations in which the dopamine transporter is pharmacologically blocked by cocaine

    Oxidation chemistry of d^0 organometallic complexes

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    Electron-transfer processes can play an important role in organometallic chemistry. Herein, we demonstrate that even d^0 organometallic complexes exhibit a rich redox chemistry and present electrochemical, kinetics, and stereochemical studies that establish a general outer-sphere oxidation process for d^0 group 4 metallocene complexes. This oxidation chemistry closely parallels the reported LMCT photochemistry of these complexes

    Asymmetric Supernovae from Magneto-Centrifugal Jets

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    Strong toroidal magnetic fields generated in stellar collapse can generate magneto-centrifugal jets in analogy to those found in simulations of black hole accretion and explain why all core collapse supernovae are found to be substantially asymmetric and predominantly bi-polar. We describe two phases: the initial LeBlanc-Wilson jet and a subsequent protopulsar or toroidal jet that propagates at about the core escape velocity. The jets will produce bow shocks that tend to expel matter, including iron and silicon, into equatorial tori, accounting for observations of the element distribution in Cas A. A magnetic ``switch'' mechanism may apply in instances of low density and large magnetic field with subsequent increase in the speed and collimation of the toroidal jet, depositing relatively little momentum. The result could be enough infall to form a black hole with a third, highly relativistic jet that could catch up to the protopulsar jet after it has emerged from the star. The interaction of these two jets could generate internal shocks and explain the presence of iron lines in the afterglow. Recent estimates that typical gamma-ray burst energy is about 3x10^50 erg imply either a very low efficiency for conversion of rotation into jets, or a rather rapid turnoff of the jet process even though the black hole still rotates rapidly. Magnetars and ``hypernovae'' might arise in an intermediate parameter regime of energetic jets that yield larger magnetic fields and provide more energy than the routine case, but that are not so tightly collimated that they yield failed supernova. (slightly abridged)Comment: AASTeX, 29 pages, 2 postscript figures, accepted by ApJ, November 20, 200
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