Legg-Calvé-Perthes disease and the risk of injuries requiring hospitalization

Background and purpose Previous studies have suggested that Legg-Calvé-Perthes disease (LCPD) is associated with repetitive trauma, coagulation problems and anatomical abnormalities of the blood supply to the femoral head. The hypothesis that repetitive trauma can affect the blood supply of the femoral head, leading to LCPD, is supported by an animal model. For evidence of an increased risk of repetitive trauma, we investigated whether patients with LCPD have a higher risk for severe injuries requiring hospitalization. Patients and methods We identified 2579 patients with LCPD in Sweden during the period 1964-2005. 13,748 individuals without LCPD were randomly selected from the Swedish general population, matched by year of birth, sex and region (control group). Cox proportional hazard regression estimated the risks. Results Compared to the control group, patients with LCPD had a modestly raised hazard ratio (HR) of 1.2 (95% CI 1.1-1.3) for injury requiring hospitalization. The risks were slightly higher for soft tissue injuries (HR = 1.3, 95% CI:1.1-1.4) than for fractures (HR = 1.1, 95% CI: 1.0-1.3) and more pronounced among females. Compared to the control group, the higher risk for injury only applied to the lower extremities (HR = 1.2, 95% CI: 1.0-1.4) in patients with LCPD. Interpretation Patients with LCPD are vulnerable to injuries which could be interpreted as a marker of hyperactive behavior. It could also implicate that anatomical changes in the bone formation or blood supply of the femoral head - increasing its sensibility for trauma - contribute to the etiology of LCPD. © Copyright: ©Nordic Orthopaedic Federation

Forest Potentials and Policy Implications: A Summary of a Study of Eastern and Western European Forest by the IIASA

National timber-assessment studies based on dynamic models are well developed in some European countries, but consistent and dynamic timber assessments for all of Europe are rare and those that exist are not based on formal quantitative models. Because of this lack, a first objective of the IIASA Forest Study was the development of a consistent and formal dynamic model for European forests. Such a model is crucial for formulating relevant forest policies throughout Europe, as well as for calculating long-term timber balance for the region. Finding solutions to the air pollution problem is not easy. Those who design a nd implement solutions to the problem must coordinate local actions to achieve regional goals, regional actions to achieve national goals, and national actions to achieve international goals. We hope that the results of the IIASA Forest Study will play a role in this process

Timelike self-similar spherically symmetric perfect-fluid models

Einstein's field equations for timelike self-similar spherically symmetric perfect-fluid models are investigated. The field equations are rewritten as a first-order system of autonomous differential equations. Dimensionless variables are chosen in such a way that the number of equations in the coupled system is reduced as far as possible and so that the reduced phase space becomes compact and regular. The system is subsequently analysed qualitatively using the theory of dynamical systems.Comment: 23 pages, 6 eps-figure

Ein Ur III-Text aus Münsteraner Privatbesitz

Uppsatsen behandlar hur USA: s president George W Bush använder civilreligiösa inslag i sin retorik under sitt första år som president. Han startade ämbetsperioden med att använda religiösa anspelningar i sitt installationstal., för att sedan fortsätta i samma anda hela året. Bush är inte den första presidenten att använda sådana retoriska knep. Ända sedan USA: s grundande har presidenterna förstärkt sin talarkonst genom att hänvisa till Gud och att landet är utvalt av Gud - ett nytt Israel. Landets presidenter har alltid varit mer eller mindre övertygade om att Gud står på USA: s sida. Detta trots att det första tillägget i USA: s konstitution föreskriver en separation mellan religion ochstat. Uppsatsen analyseras utifrån en innehållsanalys, som är en vanlig metod för att analysera politiska tal. Vår innehållsanalys består av åtta olika kategorier som speglar Bushs civilreligiösa retorik väl. Resultatet visar att Bush som president anser att det är självklart att en amerikansk president har en gudstro. Han använder ett religiöst språkbruk genom att citera ur Bibeln och Koranen i sina offentliga framträdanden. Han säger sig vara övertygad om att USA är utvalt av Gud att styra över världen. En stor del av Bushs civilreligiösa retorik går att hitta i att han försöker ena nationen genom att hänvisa till landets historia. Han visar ofta hur krigshjältar och presidenter har offrat sina liv för USA. Vi anser att Bush använder civilreligiös retorik för att ena nationen vid svåra tillfällen. Efter terrorattacken den 11: e september 2001 ökar frekvensen av civilreligion hos Bush. Det är tydligt att den amerikanske presidenten vill ena en nation i chock. Vi menar också att det av tradition förväntas att USA:s president har ett civilreligiöst språkbruk. Vi menar att Bush använder civilreligionen som en ursäkt för att inte genomföra reella politiska förändringar i samhället

The Forest Resources of the Former European USSR

This book, the second in a series, reports the results of a four-year study of the effects of air pollutants, ineffective silviculture practices and other factors on forests in the European sector of the former Soviet Union. The specific objectives of this book are: to gain an impartial view of potential developments of the forest resources in the European sector of the former USSR; to build alternative and consistent scenarios of the future developments; to illustrate the effects of forest decline from air pollutants; to identify meaningful policy options concerning the forest resources in the area; to support future policy decisions concerning the forest resources of the region

Identifying cross country skiing techniques using power meters in ski poles

Power meters are becoming a widely used tool for measuring training and racing effort in cycling, and are now spreading also to other sports. This means that increasing volumes of data can be collected from athletes, with the aim of helping coaches and athletes analyse and understanding training load, racing efforts, technique etc. In this project, we have collaborated with Skisens AB, a company producing handles for cross country ski poles equipped with power meters. We have conducted a pilot study in the use of machine learning techniques on data from Skisens poles to identify which "gear" a skier is using (double poling or gears 2-4 in skating), based only on the sensor data from the ski poles. The dataset for this pilot study contained labelled time-series data from three individual skiers using four different gears recorded in varied locations and varied terrain. We systematically evaluated a number of machine learning techniques based on neural networks with best results obtained by a LSTM network (accuracy of 95% correctly classified strokes), when a subset of data from all three skiers was used for training. As expected, accuracy dropped to 78% when the model was trained on data from only two skiers and tested on the third. To achieve better generalisation to individuals not appearing in the training set more data is required, which is ongoing work.Comment: Presented at the Norwegian Artificial Intelligence Symposium 201

Exhaust particle number of a non-road diesel engine fuelled by methyl esters with different fatty acid compositions

ArticleThe main aim of this study was to find out how methyl esters with different fatty acid compositions affect the exhaust particle numbers. Along with fossil diesel fuel oil (DFO) and renewable diesel (HVO), a high-speed non-road diesel engine was fuelled by rapeseed (RME) and soybean (SME) methyl esters. Particle numbers within the size range of 5.6–560 nm were measured by means of an engine exhaust particle sizer (EEPS). The exhaust smoke, gaseous emissions and the basic engine performance were also determined. During the measurements, the 4-cylinder, turbocharged, intercooled engine was run according to the non-road steady cycle. Methyl esters reduced particles within the size range of 70 to 200 nm. For RME and SME, both positive and significant correlations were found between the sum of the particle numbers detected above the size category of 23 nm and methyl palmitate (C16:0), methyl stearate (C18:0) and methyl linoleate (C18:2) contents at 10% load at rated speed. In terms of nitrogen oxide (NOx) and hydrocarbon (HC) emissions, HVO was beneficial while carbon monoxide (CO) emission was the lowest with DFO. The level in smoke emission was negligible

Exhaust particle size distributions of a non-road diesel engine in an endurance test

The main objective of this study was to find out how the non-road diesel engine running period of 500 hours affects the exhaust particle size distribution. By means of an engine exhaust particle sizer (EEPS), particle number was measured before the endurance test and after 250 and 500 hours of engine operation. The size distributions were determined at full and 75% loads both at rated and at intermediate speeds. The soot, gaseous emissions and the basic engine performance were also determined and lubricating oil was analysed a few times during the running period. A blend of low-sulphur fossil diesel and soybean methyl ester (B20) was used as fuel in the 4-cylinder, turbocharged, intercooled engine which was equipped with a diesel oxidation catalyst (DOC) and a selective catalytic reduction (SCR) system. All emissions were measured downstream the catalysts. During the 500 hours of operation, the particle number increased considerably within an approximate size range of 7 to 30 nm. Between the initial and final measurements, no notable differences were observed in the particle number emissions within a particle size range of 50 to 200 nm. The copper content of lubricating oil also increased significantly during the 500 hours’ experiment. One possible reason for the substantial increase in the nucleation mode particle number was assumed to be copper, which is one of the metallic elements originating from engine wear. The engine efficiency was almost equal, and the differences both in smoke and hydrocarbon emission were negligible throughout the 500 hours’ experiment.fi=vertaisarvioitu|en=peerReviewed