108 research outputs found
Seasonal Associations between Weather Conditions and SuicideâEvidence against a Classic Hypothesis
Psychiatrists, epidemiologists, and sociologists have debated the existence of an association between weather conditions and suicide seasonality since the preliminary statistical investigations in the 19th century. Provided that the effect of weather conditions on suicide operates via a dose-response-like mechanism, time-series (Box-Jenkins) analysis permits an indirect test of the hypothesis that temperature or other weather variables promote higher suicide frequencies in late spring and early summer months. The authors modeled monthly data on suicide and climatic conditions (i.e., temperature, sunshine, and precipitation data) in Switzerland. Cross-correlations between the filtered (prewhitened) residual series were calculated for the period 1881-2000, for consecutive 30-year periods, for different suicide methods, andâwith regard to the seasonality hypothesisâfor series relying on moving 1- and 3-month frames. Positive cross-correlations emerged between suicide and temperature data for the whole time series, as well as in all consecutive 30-year periods. However, cross-correlations of data series based on moving frames showed a minor peak in associations for summer frames and a major peak in associations for winter frames, the latter reflecting suicides performed mainly outdoors (being run over by a train and jumping from high places). The results represent a novel minor effect in seasonality of suicide, which is hardly compatible with the hypothesized role of temperature in suicide seasonalit
Investigation of turbulent boundary layer flows with adverse pressure gradient by means of 3D Lagrangian particle tracking with Shake-The-Box
A large-scale 3D Lagrangian particle tracking (LPT) investigation of a turbulent boundary layer (TBL) flow developing across different pressure gradient regions is presented in this study. Three high-speed multi-camera imaging systems, LED illumination and helium-filled soap bubbles (HFSB) tracers have been adopted to produce time-resolved sequences of particle images over a large volume encompassing approximately 3 m in the streamwise direction, 0:8 m in the spanwise direction and 0:25 m in the wall-normal direction. Individual tracers have been reconstructed and tracked within the imaged volume by means of the Shake-The-Box algorithm (STB, Schanz et al. (2016)); the FlowFit data assimilation algorithm (Gesemann et al. (2016)) has been used to evaluate the spatial velocity gradients and to interpolate the scattered LPT results onto a regular grid. Thanks to the large size of the investigated volume and to the time-resolved nature of the recorded images, the entire spatial extent of the large-scale coherent motions within the logarithmic region of the TBL (i.e. superstructures) could be captured and their dynamics investigated during their development over several boundary layer thickness in the streamwise direction, from the zero pressure gradient region (ZPG) to the adverse pressure gradient region (APG). Two free-stream velocities were investigated, namely 7 and 14m=s, corresponding to Ret ~ 3,000 and 5,000 respectively.
The results confirm the location and scale of the elongated high- and low-momentum structures in the logarithmic region, as well as their meandering in the spanwise direction. Two-point correlation statistics show that the width and spacing of the superstructures are not affected by the transition from the ZPG to the APG region. The analysis of the instantaneous flow realizations from both a Lagrangian and Eulerian perspective indicates the presence of significant fluid particle elements exchange across the interfaces of the large-scale structures
Undergraduate medical education in emergency medical care: A nationwide survey at German medical schools
Background Since June 2002, revised regulations in Germany have required "Emergency Medical Care" as an interdisciplinary subject, and state that emergency treatment should be of increasing importance within the curriculum. A survey of the current status of undergraduate medical education in emergency medical care establishes the basis for further committee work. Methods Using a standardized questionnaire, all medical faculties in Germany were asked to answer questions concerning the structure of their curriculum, representation of disciplines, instructors' qualifications, teaching and assessment methods, as well as evaluation procedures. Results Data from 35 of the 38 medical schools in Germany were analysed. In 32 of 35 medical faculties, the local Department of Anaesthesiology is responsible for the teaching of emergency medical care; in two faculties, emergency medicine is taught mainly by the Department of Surgery and in another by Internal Medicine. Lectures, seminars and practical training units are scheduled in varying composition at 97% of the locations. Simulation technology is integrated at 60% (n=21); problem-based learning at 29% (n=10), e-learning at 3% (n=1), and internship in ambulance service is mandatory at 11% (n=4). In terms of assessment methods, multiple-choice exams (15 to 70 questions) are favoured (89%, n=31), partially supplemented by open questions (31%, n=11). Some faculties also perform single practical tests (43%, n=15), objective structured clinical examination (OSCE; 29%, n=10) or oral examinations (17%, n=6). Conclusion Emergency Medical Care in undergraduate medical education in Germany has a practical orientation, but is very inconsistently structured. The innovative options of simulation technology or state-of-the-art assessment methods are not consistently utilized. Therefore, an exchange of experiences and concepts between faculties and disciplines should be promoted to guarantee a standard level of education in emergency medical care
Verbleib von Soziologie-AbsolventInnen der Philipps-UniversitÀt Marburg
Soziologie ist an der Philipps-UniversitĂ€t in den 1960er Jahren als akademisches Studienfach entstanden und ab 1972 ausgebaut worden. Neben den beiden Kernbereichen 'Soziologische Theorien' und 'Methoden empirischer Sozialforschung' konnten Studierende Ende der 1990er Jahre zwischen sechs speziellen Soziologien ihre Schwerpunktsetzung wĂ€hlen. Nach 30 Jahren Soziologie-Studium in Marburg erschien es sinnvoll, Daten und Informationen ĂŒber den Verbleib der bisherigen Absolventinnen und Absolventen zusammenzutragen. Dieser Aufgabe stellte sich eine Gruppe von Soziologiestudierenden im Grundstudium (2./3. bzw. 3./4. Fachsemester) zusammen mit ihrem Tutor und ihrer Dozentin im Rahmen eines ĂŒber zwei Semester laufenden Empirischen Praktikums (Oktober 2003 bis Juli 2004). In Anlehnung an Verbleibs- und Studienabbruchs-Studien anderer Hochschulen wurden Fragestellungen fĂŒr verschiedene Teiluntersuchungen und Erhebungsinstrumente entwickelt, Interviewtechniken trainiert, Daten erhoben und quantitativ bzw. qualitativ ausgewertet sowie der abschlieĂende Forschungsbericht geschrieben. Die Grundgesamtheit wurde (wegen der schwierigen Adressrecherche) auf die AbschlussjahrgĂ€nge 1990 bis 2003 beschrĂ€nkt. DurchgefĂŒhrt wurden: eine postalische Fragebogenuntersuchung aller erreichbaren AbsolventInnen (realisiert 88 Befragungen); drei berufsbiografische Interviews mit AbsolventInnenen der Jahre 1991-1996-2001; vier perspektivische Leitfadeninterviews (problemzentriert) mit AbsolventInnen des Jahres 2003; zwei Leitfadeninterviews mit einem Abbrecher bzw. einem Studienfachwechsler; Experteninterviews mit potenziellen ArbeitgebervertreterInnen. FĂŒr die Analysen wurden je nach Datenstandard statistische Verfahren, qualitative Inhaltsanalyse oder sequenzielle Analyse eingesetzt. Die Befunde ermöglichen EinschĂ€tzungen hinsichtlich der damaligen Diplom- und MagisterstudiengĂ€nge in Marburg - hinsichtlich Bachelor- und Master-StudiengĂ€ngen oder fĂŒr andere Hochschulen mĂŒsste eine Studie entsprechend modifiziert werden
Design and control of MIRA: A lightweight climbing robot for ship inspection
The inspection of marine vessels is currently performed manually. Inspectors use tools (e.g. cameras and devices for non-destructive testing) to detect damaged areas, cracks, and corrosion in large cargo holds, tanks, and other parts of a ship. Due to the size and complex geometry of most ships, ship inspection is time-consuming and expensive. The EU-funded project INCASS develops concepts for a marine inspection robotic assistant system to improve and automate ship inspections. In this paper, we introduce our magnetic wallâclimbing robot: Marine Inspection Robotic Assistant (MIRA). This semiautonomous lightweight system is able to climb a vessels steel frame to deliver on-line visual inspection data. In addition, we describe the design of the robot and its building subsystems as well as its hardware and software components
Adaptive compliance control of a multiâlegged stairâclimbing robot based on proprioceptive data
Purpose\ud
â The purpose of this paper is to describe an innovative compliance control architecture for hybrid multiâlegged robots. The approach was verified on the hybrid leggedâwheeled robot ASGUARD, which was inspired by quadruped animals. The adaptive compliance controller allows the system to cope with a variety of stairs, very rough terrain, and is also able to move with high velocity on flat ground without changing the control parameters.\ud
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Design/methodology/approach\ud
â The paper shows how this adaptivity results in a versatile controller for hybrid leggedâwheeled robots. For the locomotion control we use an adaptive model of motion pattern generators. The control approach takes into account the proprioceptive information of the torques, which are applied on the legs. The controller itself is embedded on a FPGAâbased, custom designed motor control board. An additional proprioceptive inclination feedback is used to make the same controller more robust in terms of stairâclimbing capabilities.\ud
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Findings\ud
â The robot is well suited for disaster mitigation as well as for urban search and rescue missions, where it is often necessary to place sensors or cameras into dangerous or inaccessible areas to get a better situation awareness for the rescue personnel, before they enter a possibly dangerous area. A rugged, waterproof and dustâproof corpus and the ability to swim are additional features of the robot.\ud
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Originality/value\ud
â Contrary to existing approaches, a preâdefined walking pattern for stairâclimbing was not used, but an adaptive approach based only on internal sensor information. In contrast to many other walking pattern based robots, the direct proprioceptive feedback was used in order to modify the internal control loop, thus adapting the compliance of each leg onâline
Adaptive compliance control of a multiâlegged stairâclimbing robot based on proprioceptive data
Turbulent superstructure statistics in a turbulent boundary layer with pressure gradients
In turbulent boundary layers, streamwise elongated regions of high- and low-momentum in the log-law layer that can extent up to several boundary layer thicknesses are often referred to as turbulent superstructures. These structures contain a relatively large portion of the layerâs turbulent kinetic energy and have been shown to interact with the near-wall flow structures. In the last few decades extensive research on zero-pressure gradient (ZPG) turbulent boundary layers has been done, however by comparison, the structural characteristics for adverse pressure gradient turbulent (APG) boundary layer flows are much less studied despite their strong significance aero-hydrodynamic vehicle design. Therefore, the three-dimensional dynamics of turbulent superstructures in a turbulent boundary layer flow are investigated in the Atmospheric Wind Tunnel Munich (AWM) using a multi-camera 3D time-resolved Lagrangian particle tracking approach. In this study, Lagrangian and Eulerian statistics will be used to characterize the dynamics and interaction of turbulent superstructures within a zero pressure gradient (ZPG) turbulent boundary layer at Re = 5000 or Re = 14 000 that then flows over a curved plate subjected to a favorable (FPG) and strong adverse (APG) pressure gradient, which eventually separates. An Eulerian analysis, using multi-point correlations of 3D velocity fields, found that the average superstructure topology is modulated by decelerating flow in the APG region when compared to the ZPG region, however the basic shape and spanwise pattern is preserved. Looking into the behavior of individual trajectories, it was found that the dispersion of single particles along trajectories in the log-law layer are capable of moving more than the average Eulerian superstructure spacing in the spanwise direction. Furthermore, the mean square of the single particle dispersion indicates that the maximum dispersion in the spanwise direction comes from particles released at the wall-normal location corresponding to the so-called âsecond-peak/plateauâ region in the streamwise normal Reynolds stress
Are seasonalities in suicide dependent on suicide methods? A reappraisal
In general, suicide frequencies peak in spring and early summer and depict a low in autumn and winter months. Suicide seasonality is a ubiquitous phenomenon; however, recent studies have indicated that it is related particularly to violent suicide methods. We investigated differences in suicide seasonalities by suicide methods using Swiss mortality data. The suicide data were extracted from the Swiss cause of death statistics and cover the period 1969-1994. In this period 37,518 suicides (ICD-8 codes 950-959) were registered in the mortality statistics. The data were analysed by the Edwards' method, which examines unimodal sinusoidal patterns in aggregated monthly data, and by spectral analysis with disaggregated monthly data. Overall, Swiss suicide data in 1969-1994 depict the expected pattern with a peak in May and June and a low in December. However, analyses by suicide methods show that there is no common pattern. Suicide seasonalities are absent or weak in some violent as well as non-violent methods (firearms, cutting, crashing, poisoning). Even if clearly present (hanging, drowning, jumping from high places, unspecified/other), the seasonalities show distinct patterns and cycles. Apart from sinusoidal patterns, there are also outliers: in overall data as well as in most method-specific data, the December frequencies fall more than 10% below the neighbouring months. The decrease of the frequencies culminates at Christmas/New Year and then returns to average levels. Hence, the seasonality of the overall Swiss suicide frequencies is but a compound seasonality. It largely depends on specific suicide methods and different cyclical dynamics
Are seasonalities in suicide dependent on suicide methods? A reappraisal
In general, suicide frequencies peak in spring and early summer and depict a low in autumn and winter months. Suicide seasonality is a ubiquitous phenomenon; however, recent studies have indicated that it is related particularly to violent suicide methods. We investigated differences in suicide seasonalities by suicide methods using Swiss mortality data. The suicide data were extracted from the Swiss cause of death statistics and cover the period 1969-1994. In this period 37,518 suicides (ICD-8 codes 950-959) were registered in the mortality statistics. The data were analysed by the Edwards' method, which examines unimodal sinusoidal patterns in aggregated monthly data, and by spectral analysis with disaggregated monthly data. Overall, Swiss suicide data in 1969-1994 depict the expected pattern with a peak in May and June and a low in December. However, analyses by suicide methods show that there is no common pattern. Suicide seasonalities are absent or weak in some violent as well as non-violent methods (firearms, cutting, crashing, poisoning). Even if clearly present (hanging, drowning, jumping from high places, unspecified/other), the seasonalities show distinct patterns and cycles. Apart from sinusoidal patterns, there are also outliers: in overall data as well as in most method-specific data, the December frequencies fall more than 10% below the neighbouring months. The decrease of the frequencies culminates at Christmas/New Year and then returns to average levels. Hence, the seasonality of the overall Swiss suicide frequencies is but a compound seasonality. It largely depends on specific suicide methods and different cyclical dynamics.Suicide Season Switzerland Hanging Poisoning
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