The decision-making process in antibacterial treatment of pediatric upper respiratory infections: a national prospective office-based observational study

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Scientific Opinion on the safety and efficacy of iron compounds (E1) as feed additives for all species: Ferrous sulphate monohydrate based on a dossier submitted by Kronos International, Inc.

Ferrous sulphate monohydrate is safe when supplied up to a maximum iron content per kilogram complete feedingstuff of 450 mg for bovines and poultry, 500 mg for ovines, 600 mg for pets, and 750 mg for other species/categories, except horses and fish; for piglets up to one week before weaning a maximum of 250 mg Fe/day is considered safe. Because of insufficient data on horses and fish, as a provisional measure, the current value (750 mg Fe/kg) could be maintained. The values for total dietary iron for pigs, ovines, horses, fish and other species/categories (except poultry, bovines and pets) are in line with those currently authorised. Iron from ferrous sulphate monohydrate is unlikely to modify the iron concentration in edible tissues and products of animal origin. Consumer exposure in the EU is not associated with a risk of excess iron intake to the general population. Therefore, the FEEDAP Panel does not foresee any concern for consumer safety resulting from the use of ferrous sulphate monohydrate in animal nutrition, provided that the maximum iron content in complete feedingstuffs is respected. Ferrous sulphate monohydrate is irritant and corrosive to the skin, eyes and respiratory tract. The additive contains up to 109 mg Ni/kg. Nickel is a dermal and respiratory sensitiser, and inhalation may cause lung cancer. Thus, handling the additive poses a risk to the user/worker. Considering the high concentration of iron and sulphur in soil and water, the supplementation of feed with the additive is not expected to pose an environmental risk. Ferrous sulphate monohydrate is an effective iron source for all animal species and categories. The FEEDAP Panel recommends that the currently authorised maximum iron content in complete feed be reduced for bovines and poultry from 750 to 450 mg Fe/kg, and for pets from 1250 to 600 mg Fe/kg

The medicalization of current educational research and its effects on education policy and school reforms

Este artículo parte del supuesto de la aparición de una cultura pedagogizada durante los últimos 200 años, según la cual los problemas sociales percibidos se traducen en desafíos educativos. En consecuencia, tanto la investigación como las instituciones educativas crecieron, y una política educativa surgió como resultado de las negociaciones entre los profesionales, los investigadores y los responsables políticos. El documento mantiene que algunas experiencias específicas ocurridas durante la Segunda Guerra Mundial, provocaron un cambio fundamental en el papel social y cultural de los círculos académicos, que condujo a una cultura tecnocrática caracterizada por una mayor confianza mostrada hacia los expertos en lugar de a la práctica profesional (es decir, los maestros y administradores). Bajo este cambio tecnocrático, en primer lugar surgió un sistema tecnológico de razonamiento, que luego fue sustituido por un “paradigma” médico. El nuevo paradigma condujo a una medicalización de la investigación social, en el cual se da por sentado un particular entendimiento organicista de la realidad social, y su investigación se realiza bajo las más discutibles premisas. El resultado es que pese a la creciente importancia de la investigación en general, este cambio expertocrático y médico de la investigación social dio lugar a una reducción drástica de las oportunidades reformistas al privar a las partes interesadas de una amplia gama de investigación educativa, experiencia profesional, sentido común, y debate político.This paper starts from the assumption of the emergence of an educationalized culture over the last 200 years according to which perceived social problems are translated into educational challenges. As a result, both educational institutions and educational research grew, and educational policy resulted from negotiations between professionals, researchers, and policy makers. The paper argues that specific experiences in the Second World War triggered a fundamental shift in the social and cultural role of academia, leading up to a technocratic culture characterized by confidence in experts rather than in practicing professionals (i.e., teachers and administrators). In this technocratic shift, first a technological system of reasoning emerged, and it was then replaced by a medical “paradigm.” The new paradigm led to a medicalization of social research, in which a particular organistic understanding of the social reality is taken for granted and research is conducted under the mostly undiscussed premises of this particular understanding. The result is that despite the increased importance of research in general, this expertocratic and medical shift of social research led to a massive reduction in reform opportunities by depriving the reform stakeholders of abroad range of education research, professional experience, common sense, and political deliberation.Grupo FORCE (HUM-386). Departamento de Didáctica y Organización Escolar de la Universidad de Granad

Electrically conductive plastics

Translated from German (Kunststoffe 1986 v. 76(10) p. 930-936)SIGLEAvailable from British Library Document Supply Centre- DSC:9022.381(HSE-Trans--12208)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo

A note on the application of linear wave theory at a critical level

The purpose of this note is to estimate the accuracy and practical limitations of applying linear theory at a critical level over a realistic range of atmospheric conditions and surface terrains. These estimates are made by comparing the results of a linear model with a nonlinear numerical model at a critical level. Essentially similar results are obtained form each model for wave stress, wave breaking height and wave dissipation through the critical level. Because gravity waves can be either external or internal depending on the relative sizes of the Scorer parameter and the wavenumber of the ground surface disturbance, the somewhat paradoxical result develops that wave breaking and non-linearity increases with increasing bulk Richardson number. It is recommended that steady linear wave theory be used in gravity wave drag parameterizations provided near real time profiles of background velocity and temperature are available. (orig.)17 refs.SIGLEAvailable from TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

On the composition and optical extinction of particles in the tropopause region

Liquid aerosol particles and ice crystals in subvisible cirrus clouds in the tropopause region are characterized in terms of size distributions, chemical composition, and optical extinction. These particle properties are studied by means of simple models and are related to satellite extinction measurements, particularly for midlatitudes. Sulfuric acid aerosols can take up nitric acid near the ice frost point, just before ice nucleation. Aerosols in the tropopause region may show a larger spread of extinction and extinction ratios at different wavelengths than background stratospheric aerosols. The high surface areas and low extinction ratios of subvisible cirrus deduced from satellite observations are unlikely to be due purely to aerosols, except for high sulfate loadings. It is shown that mixtures of liquid aerosols and ice particles can more readily explain these data with only small cloud fractions along the line of sight of the optical sensors. The efficiency of heterogeneous chlorine activation in aerosol/cloud mixtures, the availability of water vapor, sulfate, and nitrate, and the effects of temperature, ammonium, ice nuclei and aircraft emissions on the properties of particles in the tropopause region are explored. (orig.)105 refs.Available from TIB Hannover: RR 6341(118) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Physicochemistry of aircraft generated liquid aerosols, soot, and ice particles - 2. Comparison with observations and sensitivity studies

Results from a coupled microphysical-chemical-dynamical trajectory box model have been compared to recent in situ observations of particles generated in the wake of aircraft. Sulfur emissions mainly cause the formation of ultrafine volatile particles in young aircraft plumes (mean number radius 1-10 nm). Volatile particle numbers range between 10"1"6-10"1"7 per kg fuel for average to high fuel sulfur levels, exceeding typical soot emission indices by a factor 10-100. High emission levels of SO_3 or yet unknown sulfur oxidation pathways are not necessarily required to explain these volatile particle abundances. Model results come into closer agreement with observations when chemi-ions from fuel combustion are included in the aerosol dynamics. Ice particles (mean number radius <1 #mu#m) in young contrails mainly nucleate on exhaust aerosols. Homogeneous freezing of volatile particles and heterogeneous freezing in liquid soot coatings are competitive processes leading to ice formation, depending on the temperature and level of oxidized sulfur species. Metal particles emitted by jet engines may contribute to the formation of larger (>1 #mu#m) crystals. Contrails with larger crystals would also form without soot and sulfur emissions. Simulations indicate that the lifecycle of cirrus clouds can be modified in the presence of exhaust aerosols. Main open issues concern the conversion of fuel sulfur leading to emissions of SO_3, the freezing properties of soot, and the ability to accurately determine experimentally particle abundances and size distributions in the ultrafine size region. (orig.)SIGLEAvailable from TIB Hannover: RR 6341(91) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman