1,173 research outputs found
Junge Rehabilitanden zwischen Schule und Erwerbsleben: Maßnahmen der beruflichen Ersteingliederung anhand empirischer Befunde aus der IAB-Panelbefragung der Rehabilitanden 2007 und 2008
Im vorliegenden Forschungsbericht werden die Maßnahmeteilnahmen beruflicher Rehabilitanden im Rahmen der Ersteingliederung bei der Bundesagentur für Arbeit untersucht. Datengrundlage ist eine IAB-Befragung von Rehabilitanden, die im Jahr 2006 eine Maßnahme bei der Bundesagentur für Arbeit abgeschlossen haben. Im Fokus steht die sequenzanalytische Auswertung der Maßnahmen beruflicher Rehabilitation, die im Kontext der erwerbsbiographischen Statuspassage in den ersten fünf Jahren nach Verlassen des allgemeinbildenden Schulsystems betrachtet werden. Der Übergangsprozess junger Rehabilitanden ins Erwerbssystem ist in nur wenigen Fällen maßgeblich durch die gesundheitliche Lage geprägt - entsprechend sieht sich eine Mehrheit trotz (oftmals mehrfacher) gesundheitlicher Erkrankungen und Behinderungen nicht in ihrer Berufsausübung eingeschränkt. Das häufigste Übergangsmuster besteht wie erwartet aus der Maßnahmenkette Berufsvorbereitung und Berufsausbildung (rund 41 Prozent). Ein Fünftel der Rehabilitanden in Ersteingliederung tritt als ausbildungsreife Personen direkt eine Berufsausbildung an. Diesen 60 Prozent junger Rehabilitanden mit Arbeitsmarktorientierung und -potenzial stehen gut 25 Prozent gegenüber, die Schwierigkeiten haben, zu einem Ausbildungsplatz oder einer Arbeitsstelle zu kommen und mehrheitlich in berufsvorbereitenden Maßnahmen oder Arbeitslosigkeit verbleiben, sowie weitere zwölf Prozent, die nur wenige Angaben zu ihrer erwerbsbiographischen Situation machen. Künftige Forschungsarbeiten sollten klären, durch welche Einflüsse die Übergangstypen strukturiert werden und in welchem Ausmaß sie über den weiteren beruflichen Werdegang junger Rehabilitanden entscheiden.This research report investigates the participation of adolescent persons and young adults in measures of vocational rehabilitation for the purposes of primary labour market integration. A survey of the Institute for Employment Research (IAB) is used covering data on vocational rehabilitants who completed a measure within the German Federal Employment Agency (BA) in 2006. The analysis focuses on the biographic transition between school and labour market as a context in which the measures of vocational rehabilitation are embedded. Only a small cluster of the pathways is characterised by a significant amount of illness episodes. Although adolescent and young adult rehabilitants often show multiple disabilities, they rate their health situation as good regarding their ability to participate in working life. The most frequent transition pathway is made up of measures of vocational preparation and vocational training (nearly 41 percent). Moreover, about 20 percent of adolescent rehabilitants are able to start vocational education just right after leaving the general education system. IAB-Forschungsbericht 14/2012 6 However, there are 25 percent of young rehabilitants who have problems getting an apprentice position or a job, and 12 percent of rehabilitants providing little information about their employment situation during the observation period. Further research will deal with effects structuring the transition pathways and the pathways' effects on later career stages
Abundances and variability of tropospheric volatile organic compounds at the South Pole and other Antarctic locations
Multiyear (2000-2006) seasonal measurements of carbon monoxide, hydrocarbons, halogenated species, dimethyl sulfide, carbonyl sulfide and C1-C4 alkyl nitrates at the South Pole are presented for the first time. At the South Pole, short-lived species (such as the alkenes) typically were not observed above their limits of detection because of long transit times from source regions. Peak mixing ratios of the longer lived species with anthropogenic sources were measured in late winter (August and September) with decreasing mixing ratios throughout the spring. In comparison, compounds with a strong oceanic source, such as bromoform and methyl iodide, had peak mixing ratios earlier in the winter (June and July) because of decreased oceanic production during the winter months. Dimethyl sulfide (DMS), which is also oceanically emitted but has a short lifetime, was rarely measured above 5 pptv. This is in contrast to high DMS mixing ratios at coastal locations and shows the importance of photochemical removal during transport to the pole. Alkyl nitrate mixing ratios peaked during April and then decreased throughout the winter. The dominant source of the alkyl nitrates in the region is believed to be oceanic emissions rather than photochemical production due to low alkane levels.Sampling of other tropospheric environments via a Twin Otter aircraft included the west coast of the Ross Sea and large stretches of the Antarctic Plateau. In the coastal atmosphere, a vertical gradient was found with the highest mixing ratios of marine emitted compounds at low altitudes. Conversely, for anthropogenically produced species the highest mixing ratios were measured at the highest altitudes, suggesting long-range transport to the continent. Flights flown through the plume of Mount Erebus, an active volcano, revealed that both carbon monoxide and carbonyl sulfide are emitted with an OCS/CO molar ratio of 3.3 × 10-3 consistent with direct observations by other investigators within the crater rim. © 2010
Power-dependent speciation of volatile organic compounds in aircraft exhaust
As part of the third NASA Aircraft Particle Emissions Experiment (APEX-3, November 2005), whole air samples were collected to determine the emission rates of volatile organic compounds (VOCs) from aircraft equipped with three different gas-turbine engines (an Allison Engine 3007-A1E, a Pratt-Whitney 4158, and a Rolls-Royce RB211-535E4B). Samples were collected 1 m behind the engine exhaust plane of the engines while they were operated at powers ranging from idle up to 30% of maximum rated thrust.Exhaust emission indices (mass emitted per kilogram of fuel used) for CO and non-methane hydrocarbons (NMHCs) were calculated based on enhancements over background relative to CO 2. Emissions of all NMHCs were greatest at low power with values decreasing by an order of magnitude with increasing power. Previous studies have shown that scaling idle hydrocarbon emissions to formaldehyde or ethene (which are typically emitted at a ratio of 1-to-1 at idle) reduces variability amongst engine types. NMHC emissions were found to scale at low power, with alkenes contributing over 50% of measured NMHCs. However, as the power increases hydrocarbon emissions no longer scale to ethene, as the aromatics become the dominant species emitted. This may be due in part to a shift in combustion processes from thermal cracking (producing predominantly alkenes) to production of new molecules (producing proportionally more aromatics) as power increases. The formation of these aromatics is an intermediate step in the production of soot, which also increases with increasing power. The increase in aromatics relative to alkenes additionally results in a decrease in the hydroxyl radical reactivity and ozone formation potential of aircraft exhaust.Samples collected 30 m downwind of the engine were also analyzed for NMHCs and carbonyl compounds (acetone, 2-butanone and C 1-C 9 aldehydes). Formaldehyde was the predominant carbonyl emitted; however, the ratio of ethene-to-formaldehyde varied between the aircraft, possibly due to the sampling of transient emissions such as engine start-up and power changes. A large portion of the measured emissions (27-42% by mass) in the plume samples was made up of hazardous air pollutants (HAPs) with oxygenated compounds being most significant. © 2012
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Measurements of nonmethane hydrocarbons in 28 United States cities
Between 1999 and 2005 a sampling campaign was conducted to identify and quantify the major species of atmospheric nonmethane hydrocarbons (NMHCs) in United States cities. Whole air canister samples were collected in 28 cities and analyzed for methane, carbon monoxide (CO) and NMHCs. Ambient mixing ratios exhibited high inter- and intra-city variability, often having standard deviations in excess of 50% of the mean value. For this reason, ratios of individual NMHC to CO, a combustion tracer, were examined to facilitate comparison between cities. Ratios were taken from correlation plots between the species of interest and CO, and most NMHCs were found to have correlation coefficients (r2) greater than 0.6, particularly ethene, ethyne and benzene, highlighting the influence of vehicular emissions on NMHC mixing ratios. Notable exceptions were the short-chain alkanes, which generally had poor correlations with CO. Ratios of NMHC vs. CO were also used to identify those cities with unique NMHC sources. © 2007 Elsevier Ltd. All rights reserved
High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
Polar Kerr effect in the spin-triplet superconductor Sr2RuO4 was measured
with high precision using a Sagnac interferometer with a zero-area Sagnac loop.
We observed non-zero Kerr rotations as big as 65 nanorad appearing below Tc in
large domains. Our results imply a broken time reversal symmetry state in the
superconducting state of Sr2RuO4, similar to He3-A
Pathophysiological Implications of Different Bicuspid Aortic Valve Configurations
There are numerous types of bicuspid aortic valve (BAV) configurations. Recent findings suggest that various BAV types represent different pathophysiological substrates on the aortic media level. Data imply that the BAV type is probably not related to location and extent of the aneurysm. However, BAV type is likely linked to the severity of aortic media disease. Some BAVs with raphe seem more aggressive than BAV without a raphe. Cusp fusion pattern, altered hemodynamics, and the qualitative severity of the disease in the aortic media might on the one hand share the same substrate. On the other hand, the aortopathy's longitudinal extent and location may represent a different pathophysiological substrate, probably dictated by the heritable aspects of BAV disease. The exact nature of the relation between BAV type and the aneurysm's location and extent as well as to the risk of aortic complications remains unclear. This paper reviews results of recent human and experimental studies on the significance of BAV types for local aortic media disease and location and extent of the aortopathy. We describe the known and hypothesized hemodynamic and hereditary factors that may result in aortic aneurysm formation in BAV patients
Development of a frequency-detuned interferometer as a prototype experiment for next-generation gravitational-wave detectors
We report on our prototype experiment that uses a 4-m detuned resonant sideband extraction interferometer with suspended mirrors, which has almost the same configuration as the next-generation, gravitational-wave detectors. We have developed a new control scheme and have succeeded in the operation of such an interferometer with suspended mirrors for the first time ever as far as we know. We believe that this is the first such instrument that can see the radiation pressure signal enhancement, which can improve the sensitivity of next-generation gravitational-wave detectors
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