2,130 research outputs found

    Proof firm downsizing and diagnosis-specific disability pensioning in Norway

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    <br>Background: We wanted to investigate if firm downsizing is related to an increased rate of disability pensions among the former employed, especially for those with musculoskeletal and psychiatric diagnoses, and for those having to leave the firm.</br> <br>Methods: Statistics Norway provided a linked file with demographic information and all social security grants from the National Insurance Administration for 1992–2004 for all inhabitants in Norway. Our sample was aged 30–55 years in 1995, being alive, employed and not having a disability pension at the end of 2000. Downsizing was defined as percent change in number of employed per firm from 1995 to end 2000. Employment data were missing for 25.6% of the sample.</br> <br>Results: Disability pension rates in the next four years were 25% higher for those experiencing a 30-59% downsizing than for those not experiencing a reduction of the workforce. 1-29% and 60-100% downsizing did not have this effect. Stayers following down-sizing had higher disability pension rates than leavers. What we have called complex musculoskeletal and psychiatric diagnoses were relatively most common.</br> <br>Conclusion: Moderate downsizing is followed by a significant increase in disability pension rates in the following four years, often with complex musculoskeletal and psychiatric diagnoses.</br&gt

    On the stability of the atmosphere-vegetation system in the Sahara/Sahel region

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    A conceptual model has been developed for the analysis of atmosphere-vegetation interaction in subtropical deserts. The model can exhibit multiple stable states-in the system: a "desert" equilibrium with low precipitation and absent vegetation and a "green" equilibrium with moderate precipitation and permanent vegetation cover. The conceptual model is applied to interpret the results of two climate-vegetation models: a comprehensive coupled atmosphere-biome model and a simple hox model. In both applications, two stable states exist for the western Sahara/Sahel region for the present-day climate, and the only green equilibrium is found for the mid-Holocene climate. The latter agrees well with paleoreconstructions of Sahara/Sahel climate and vegetation. It is shown that for present-day climate the green equilibrium is less probable than the desert equilibrium, and this explains the existence of the Sahara desert as it is today. The difference in albedo between the desert and vegetation cover appears to be the main parameter that controls an existence of multiple stable states. The Charney's mechanism of self-stabilization of subtropical deserts is generalized by accounting for atmospheric hydrology, the heat and moisture exchange at the side boundaries, and taking into account the dynamic properties of the surface. The generalized mechanism explains the self-stabilization of both desert and vegetation in the western Sahara/Sahel region, The role of surface roughness in climate-vegetation interaction is shown to be of secondary importance in comparison with albedo. Furthermore, for the high albedo, precipitation increases with increasing roughness while, for the low albedo, the opposite is found

    Relationship Between Health and GPA When Comparing Traditional Undergraduate Students at the University of Maine in Orono

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    Purpose: The primary relationship this research assesses is between health and academic performance. In addition, it looks at the differences in this relationship for resident students as compared to commuter students. Methods: The participants were all UMaine undergraduate students. The inclusion criteria for the participants are as follows: 18-24 years old, never have been married, not a Division I athlete and full-time student during the spring semester of 2015. A paper- based self-reported survey was distributed using a convenience sample due to the fact that the primary investigator only asked professors she knew if she could distribute the survey during their class time. SPSS was used for the statistical analyses. Results: It was found that resident students had higher GPAs than commuters (p = 0.017). Also, GPA was associated with perceived stress (p = 0.029) as well as perceived health (p = 0.050). Additionally, residence was related to the number of hours worked each week (p = 0.007) and perceived health (p = 0.040). Conclusion: It can be concluded that living on campus would allow for a higher GPA, decreased stress levels and increased perceived health. However, the commuter student population has been consistently elevated indicating that the University of Maine may need to take action to provide more on campus living for the wellbeing of its students

    Astrometric Positions and Proper Motions of 19 Radio Stars

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    We have used the Very Large Array, linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 19 radio stars in the International Celestial Reference Frame (ICRF). The positions of these stars were directly linked to the positions of distant quasars through phase referencing observations. The positions of the ICRF quasars are known to 0.25 mas, thus providing an absolute reference at the angular resolution of our radio observations. Average values for the errors in our derived positions for all sources were 13 mas and 16 mas in R.A. and declination respectively, with accuracies approaching 1-2 mas for some of the stars observed. Differences between the ICRF positions of the 38 quasars, and those measured from our observations showed no systematic offsets, with mean values of -0.3 mas in R.A. and -1.0 mas in declination. Standard deviations of the quasar position differences of 17 mas and 11 mas in R.A. and declination respectively, are consistent with the mean position errors determined for the stars. Our measured positions were combined with previous Very Large Array measurements taken from 1978-1995 to determine the proper motions of 15 of the stars in our list. With mean errors of approximately 1.6 mas/yr, the accuracies of our proper motions approach those derived from Hipparcos, and for a few of the stars in our program, are better than the Hipparcos values. Comparing the positions of our radio stars with the Hipparcos catalog, we find that at the epoch of our observations, the two frames are aligned to within formal errors of approximately 3 mas. This result confirms that the Hipparcos frame is inertial at the expected level.Comment: 20 pages, 9 figures Accepted by the Astronomical Journal, 2003 March 1

    The mystery of the end of the green Sahara

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    Mit dem Erdsystemmodell des Max-Planck-Instituts für Meteorologie haben wir die Änderungen im globalen Klimasystem während der letzten 8000 Jahre in einer räumlich detaillierten Darstellung berechnet. So konnten wir einen Teil des Rätsels um das Ende der grünen Sahara lösen. Rekonstruktionen zeigen ein komplexes Änderungsmuster. In unserer Simulation wird das Ende der feuchten Phase nicht nur vom Rückzug des Monsuns, sondern auch von der Änderung der Zugbahn extratropischer Tiefdruckgebiete bestimmt. Als deren Zusammenspiel vor rund 4000 Jahren aufbrach, nahmen Niederschlag und Vegetation in der Westsahara rasch abWith the Earth System Model of the Max Planck Institute for Meteorology we have calculated the changes in the global climate system during the last 8000 years in a spatially detailed representation. This enabled us to solve part of the mystery about the end of the green Sahara. Reconstructions show a complex structure. In our simulation, the end of the humid phase is determined not only by the retreat of the monsoon but also by the change in the path of extratropical troughs. When their interplay broke up about 4000 years ago, the precipitation and vegetation in the Western Sahara rapidly decreased

    Simulation of the last glacial cycle with a coupled climate ice-sheet model of intermediate complexity

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    A new version of the Earth system model of intermediate complexity, CLIMBER-2, which includes the three-dimensional polythermal ice-sheet model SICOPOLIS, is used to simulate the last glacial cycle forced by variations of the Earth's orbital parameters and atmospheric concentration of major greenhouse gases. The climate and ice-sheet components of the model are coupled bi-directionally through a physically-based surface energy and mass balance interface. The model accounts for the time-dependent effect of aeolian dust on planetary and snow albedo. The model successfully simulates the temporal and spatial dynamics of the major Northern Hemisphere (NH) ice sheets, including rapid glacial inception and strong asymmetry between the ice-sheet growth phase and glacial termination. Spatial extent and elevation of the ice sheets during the last glacial maximum agree reasonably well with palaeoclimate reconstructions. A suite of sensitivity experiments demonstrates that simulated ice-sheet evolution during the last glacial cycle is very sensitive to some parameters of the surface energy and mass-balance interface and dust module. The possibility of a considerable acceleration of the climate ice-sheet model is discussed

    Self-organized pore formation and open-loop-control in semiconductor etching

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    Electrochemical etching of semiconductors, apart from many technical applications, provides an interesting experimental setup for self-organized structure formation capable e.g. of regular, diameter-modulated, and branching pores. The underlying dynamical processes governing current transfer and structure formation are described by the Current-Burst-Model: all dissolution processes are assumed to occur inhomogeneously in time and space as a Current Burst (CB); the properties and interactions between CB's are described by a number of material- and chemistry- dependent ingredients, like passivation and aging of surfaces in different crystallographic orientations, giving a qualitative understanding of resulting pore morphologies. These morphologies cannot be influenced only by the current, by chemical, material and other etching conditions, but also by an open-loop control, triggering the time scale given by the oxide dissolution time. With this method, under conditions where only branching pores occur, the additional signal hinders side pore formation resulting in regular pores with modulated diameter

    Contribution of oceanic and vegetation feedbacks to Holocene climate change in monsoonal Asia

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    The impact of vegetation-atmosphere and ocean-atmosphere interactions on the mid- to late Holocene climate change as well as their synergy is studied for different parts of the Asian monsoon region, giving consideration to the large climatic and topographical heterogeneity in that area. We concentrate on temperature and precipitation changes as the main parameters describing monsoonal influenced climates. For our purpose, we analyse a set of coupled numerical experiments, performed with the comprehensive Earth system model ECHAM5/JSBACH-MPIOM under present-day and mid-Holocene (6 k) orbital configurations (Otto et al., 2009b). The temperature change caused by the insolation forcing reveals an enhanced seasonal cycle, with a pronounced warming in summer (0.58 K) and autumn (1.29 K) and a cooling in the other seasons (spring: -1.32 K; winter: -0.97 K). Most of this change can be attributed to the direct response of the atmosphere, but the ocean, whose reaction has a lagged seasonal cycle (warming in autumn and winter, cooling in the other seasons), strongly modifies the signal. The simulated contribution of dynamic vegetation is small and most effective in winter, where it slightly warms the near-surface atmosphere (approx. 0.03 K). The temperature difference attributed to the synergy is on average positive, but also small. Concerning the precipitation, the most remarkable change is the postponement and enhancement of the Asian monsoon (0.46 mm/day in summer, 0.53 mm/day in autumn), mainly related to the direct atmospheric response. On regional average, the interactive ocean (ca. 0.18 mm/day) amplifies the direct effect, but tends to weaken the East Asian summer monsoon and strongly increases the Indian summer monsoon rainfall rate (0.68 mm/day). The influence of dynamic vegetation on precipitation is comparatively small (<0.04 mm/day). The synergy effect has no influence, on average
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