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Background: Bedside courses are of outstanding importance when training medical students. The fact that less and less teaching is taking place nowadays at the patient's bedside makes it all the more important that the available time be put to effective use. The aim of this study was to check whether structured improvement measures in the course (scripts, lecturer briefing, e-learning cases) would improve the abilities of the students on the basis of a subjective self-assessment as well as an external assessment by the lecturers with respect to clinical abilities. Methods: Bedside teaching takes place in the fourth study year in the Medical Clinics of the TU Munich. Both students and lecturers had the chance to hand in an anonymous, quantitative self- and external assessment of the clinical abilities of the students (German grading system) after every course date. This assessment took place online in the three categories "Medical history & examination", "Diagnosis" and "Therapy". An overall period of four semesters, each with 6 course dates, was investigated. After two of the total of four semesters in the study, the course was changed by introducing scripts, lecturer briefing as well as interactive e-learning cases. The self- and external assessment was compared both within the semester (date 1-3: A; date 4-6: B), during the course as well as before and after introducing the improvement measures ("before" (T0): SS 2012, SS 2013, "after" (T1): WS 2013/2014, SS 2014).Results: There was a significant improvement in one's own abilities on the basis of the self-assessment within each semester when comparing the first (A) and the last (B) course dates. Moreover, there was a significant improvement in the performances in all three categories when T0 was compared with T1, from both the point of view of the students ("Medical history & examination": T0 =2.5±0.9, T1=2.2±0.7, pp

We linked hydraulic vulnerability in Norway spruce (Picea abies (L.) Karst.) trunkwood with different cambial age to wood density and applied the findings on annual density variations in healthy and declining trees from southern Norway during 1990 to 2010. We hypothesized that drought stress due to the 2003 or 2006 European heat waves were the triggers for tree decline and focused analyses on the structure of wood that was produced after, as well as before, signs of stress, i.e., when decreases in height or diameter growth were visible. In the data set comprising previously published and new measurements, [P.sub.50], i.e., the pressure potential necessary to induce a 50% loss in hydraulic conductivity, was negatively related to wood density. Declining trees produced wider annual rings with lower density than vigorous trees before their radial and height increment started to decline in 2003 or 2006. Trees that produced low-density wood under favorable water availability were more stressed by a sudden drought event because of higher [P.sub.50] values in their sapwood. Due to the strong genotypic relationship between wood density and growth, we suggest that spruce trees selected for fast growth might experience limited hydraulic performance under the impact of extreme heat waves. Resume: Nous avons relie la vulnerabilite hydraulique dans le bois de tronc d'age cambial variable a la densite du bois chez l'epicea commun (Picea abies (L.) Karst.) et nous avons applique les resultats aux variations annuelles de densite dans des arbres sains et deperissants croissant dans le sud de la Norvege, de 1990 a 2010. Nous avons fait l'hypothese que le stress du a la secheresse causee par les vagues de chaleur de 2003 et 2006 en Europe avait declenche le deperissement des arbres et nous avons axe les analyses sur la structure du bois produit apres aussi bien qu'avant l'apparition des signes de stress, c.-a-d. lorsque la diminution de croissance en hauteur et en diametre est devenue visible. Dans le jeu de donnees compose de mesures deja publiees et de nouvelles mesures, [P.sub.50], c.-a-d. le potentiel hydrique qui entraine une perte de 50 % de la conductivite hydraulique, etait negativement relie a la densite du bois. Les arbres deperissants produisaient des cernes annuels plus larges avec une densite plus faible que les arbres vigoureux avant que leur accroissement radial et en hauteur commence a diminuer en 2003 ou 2006. Les arbres qui produisaient du bois de faible densite dans des conditions de disponibilite hydrique favorables etaient plus stresses par un episode soudain de secheresse parce que la valeur de [P.sub.50] dans leur bois d'aubier etait plus elevee. Etant donne l'etroite relation genotypique entre la densite du bois et la croissance, nous croyons que les epiceas selectionnes pour leur croissance rapide pourraient avoir une moins bonne performance hydraulique sous l'impact de vagues de chaleur extreme. [Traduit par la Redaction], Introduction Frequently occurring extreme weather events in the northern hemisphere such as the European heat waves of 2003 and 2006 (Intergovernmental Panel on Climate Change (IPCC) 2012) are a challenge [...]

Climate change‐related environmental stress has been recognized as a driving force in accelerating forest mortality over the last decades in Central Europe. Here, we aim to elucidate the thermal sensitivity of three native conifer species, namely Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and silver fir (Abies alba), and three non‐native species, namely Austrian pine (Pinus nigra), Douglas fir (Pseudotsuga menziesii) and Atlas cedar (Cedrus atlantica).Thermal sensitivity, defined here as a decline of the maximum quantum yield of photosystem II (Fv/Fm) with increasing temperature, was measured under varying levels of heat stress and compared with the turgor loss point (πtlp) as a drought resistance trait. We calculated three different leaf thermotolerance traits: the temperature at the onset (5%) of the Fv/Fm decline (T5), the temperature at which Fv/Fm was half the maximum value (T50) and the temperature at which only 5% Fv/Fm remained (T95).T5 ranged from 38.5 ± 0.8 °C to 43.1 ± 0.6 °C across all species, while T50 values were at least 9 to 11 degrees above the maximum air temperatures on record for all species. Only Austrian pine had a notably higher T5 value than recorded maximum air temperatures. Species with higher T5 values were characterized by a less negative πtlp compared to species with lower T5.The six species could be divided into 'drought‐tolerant heat‐sensitive' and 'drought‐sensitive heat‐tolerant' groups. Exposure to short‐term high temperatures thus exhibits a considerable threat to conifer species in Central European forest production systems. [ABSTRACT FROM AUTHOR]

A study of the long-term changes of various climatic extremes was made jointly by a number of European countries. It was found that the changes in maximum and minimum temperatures follow, in broad terms, the corresponding well-documented mean temperature changes. Minimum temperatures, however, have increased slightly more than maximum temperatures, although both have increased. As a result, the study confirms that the diurnal temperature range has mostly decreased during the present century in Northern and Central Europe. Frost has become less frequent. Two extreme-related precipitation characteristics, the annual maximum daily precipitation and the number of days with precipitation [greater than or equal to] 10 mm, show no major trends or changes in their interannual variability. An analysis of return periods indicated that in the Nordic countries there were high frequencies of 'extraordinary' 1-day rainfalls both in the 1930s and since the 1980s. There have been no long-term changes in the number of high wind speeds in the German Bight. Occurrences of thunderstorms and hails show a decreasing tendency in the Czech Republic during the last 50 years. Finally, using proxy data sources, a 500-year temperature and precipitation event graph for the Swiss Mittelland is presented. It shows large interdecadal variations as well as the exceptionality of the latest decade 1986-1995.

Presents a study which investigated the oxidation of titanium disilicide on polycrystalline silicon-coated substrates by steam oxidation. Analysis of the films by Rutherford backscattering spectrometry and transmission electron microscopy; Comparison of oxidation and pressure to the calculated values for single-crystal silicon substrate oxidation; Relation between temperature and the diffusional transport of silicon through the silicide grain boundaries.