2,670 research outputs found
A methodology to allow avalanche forecasting on an information retrieval system
This paper presents adaptations and tests undertaken to allow an information retrieval (IR) system to forecast the likelihood of avalanches on a particular day. The forecasting process uses historical data of the weather and avalanche conditions for a large number of days. A method for adapting these data into a form usable by a text-based IR system is first described, followed by tests showing the resulting system’s accuracy to be equal to existing ‘custom built’ forecasting systems. From this, it is concluded that the adaptation methodology is effective at allowing such data to be used in a text-based IR system. A number of advantages in using an IR system for avalanche forecasting are also presented
Collars and partitions of hyperbolic cone-surfaces
For compact Riemann surfaces, the collar theorem and Bers' partition theorem
are major tools for working with simple closed geodesics. The main goal of this
paper is to prove similar theorems for hyperbolic cone-surfaces. Hyperbolic
two-dimensional orbifolds are a particular case of such surfaces. We consider
all cone angles to be strictly less than to be able to consider
partitions.Comment: 11 pages, 9 figures; v2: minor changes, to appear in Geometriae
Dedicat
Transformations between the theoretical and observational planes in the HST-NICMOS and WFPC2 photometric systems
Color-temperature relations and bolometric corrections in the HST-NICMOS
F1110W, F160W and F222M and in the WFPC2 F439W, F555W and F814W photometric
systems, using two different sets of model atmospheres, have been derived. This
database of homogeneous, self-consistent transformations between the
theoretical and observational planes also allows combinations of visual and
infrared quantities, without any further transformation between the two
different photometric systems. The behavior of the inferred quantities with
varying the stellar parameters, the adopted model atmospheres and the
instrumental configurations are investigated. Suitable relations to transform
colors and bolometric corrections from HST to ground-based photometric systems
are also provided.Comment: 22 pages, 14 figure
Status febrilis mit Bewusstlosigkeit
Zusammenfassung: Eine zerebrale Beteiligung bei Malaria mit Plasmodium vivax ist ungewöhnlich. Diese schwere Form der Malaria ist üblicherweise durch Plasmodium falciparum bedingt. Wir berichten über eine 18-jährige Patientin aus Pakistan mit langjähriger intermittierender Fieberanamnese, welche 4Monate nach Einreise in die Schweiz erstmals an einer zerebralen Vivax-Malaria erkrankt. Die eindrückliche neurologische Symptomatik mit Amaurosis und Bewusstseinsstörung bildete sich in diesem Fall unter Therapie in wenigen Tagen zurück. Jedoch sind Todesfälle bei zerebraler Malaria durch Plasmodium vivax beschriebe
Long-term Outcome after Surgical Closure of Atrial Septal Defect in Childhood with Extensive Assessment Including MRI Measurement of the Ventricles
Surgical closure of the secundum type of atrial septal defect (ASD) in childhood leads to excellent survival. However, relevant morbidity has been reported. Transcatheter closure of these defects has now become an alternative approach. To compare the results of the two different interventions, reliable data are needed on the long-term morbidity after defect closure with both methods. Patients were evaluated after a minimum of 10 years after surgical closure of an ASD in childhood. Assessment included analysis of perioperative data, interview, clinical examination, electrocardiogram, (ECG), 24-hour ECG, ergometry, chest radiograph, echocardiography, and MRI. A total of 66 patients underwent operation between 1971 and 1986 at our institution. Forty-eight of them (73%) were interviewed and 38 (58%) participated fully in the study program. Eighteen (27%) either refused to participate or were lost to follow-up. There were no substantial residual disorders, such as arrhythmias, right-sided heart dilatation, pulmonary hypertension, or reduced work capacity. Surgical closure of an ASD in childhood has an excellent long-term outcome. Surgical closure is thus the standard against which transcatheter closure needs to be measure
Stable Isotope Event Markers Near the Permo-Triassic Boundary in the Karavanke Mountains (Slovenia)
Stable isotope analyses of carbonates and organic matter from the Permo-Triassic boundary section in the Karavanke Mountains, Slovenia, indicate a further example of the “light carbon” event across the boundary. In this section the changes in carbon isotope values were a direct result of the culmination of the marine regression and associated events at the end of the Permian, which caused a drop in primary productivity, as well as related local environmental changes, with no evidence of any considerable diagenetic overprint
Initial Mass Function Effects on the Colour Evolution of Disk Galaxies
Aims. In this work, we want to find out if the IMF can be determined from colour images, integrated colours, or mass-to-light ratios, especially at high redshift, where galaxies cannot be resolved into individual stars, which would enable us to investigate dependencies of the IMF on cosmological epoch.
Methods. We use chemo-dynamical models to investigate the influence of the Initial Mass Function (IMF) on the evolution of a Milky Way-type disk galaxy, in particular of its colours.
Results. We find that the effect of the IMF on the internal gas absorption is larger than its effect on the light from the stellar content. However, the two effects work in the opposite sense: An IMF with more high mass stars leads to brighter and bluer star-light, but also to more interstellar dust and thus to more absorption, causing a kind of “IMF degeneracy”. The most likely wavelength region in which to detect IMF effects is the infrared (i.e., JHK). We also provide photometric absorption and inclination corrections in the SDSS ugriz and the HST WFPC2 and NICMOS systems
Bayesian multi-model projection of climate: bias assumptions and interannual variability
Current climate change projections are based on comprehensive multi-model ensembles of global and regional climate simulations. Application of this information to impact studies requires a combined probabilistic estimate taking into account the different models and their performance under current climatic conditions. Here we present a Bayesian statistical model for the distribution of seasonal mean surface temperatures for control and scenario periods. The model combines observational data for the control period with the output of regional climate models (RCMs) driven by different global climate models (GCMs). The proposed Bayesian methodology addresses seasonal mean temperatures and considers both changes in mean temperature and interannual variability. In addition, unlike previous studies, our methodology explicitly considers model biases that are allowed to be time-dependent (i.e. change between control and scenario period). More specifically, the model considers additive and multiplicative model biases for each RCM and introduces two plausible assumptions ("constant bias” and "constant relationship”) about extrapolating the biases from the control to the scenario period. The resulting identifiability problem is resolved by using informative priors for the bias changes. A sensitivity analysis illustrates the role of the informative prior. As an example, we present results for Alpine winter and summer temperatures for control (1961-1990) and scenario periods (2071-2100) under the SRES A2 greenhouse gas scenario. For winter, both bias assumptions yield a comparable mean warming of 3.5-3.6°C. For summer, the two different assumptions have a strong influence on the probabilistic prediction of mean warming, which amounts to 5.4°C and 3.4°C for the "constant bias” and "constant relation” assumptions, respectively. Analysis shows that the underlying reason for this large uncertainty is due to the overestimation of summer interannual variability in all models considered. Our results show the necessity to consider potential bias changes when projecting climate under an emission scenario. Further work is needed to determine how bias information can be exploited for this tas
Differences of disease progression in congestive heart failure due to alcoholic as compared to idiopathic dilated cardiomyopathy
In patients with alcoholic cardiomyopathy there is evidence that mild heart failure is reversible if patients abstain from alcohol, but there is no consensus whether the disease is progressive once structural myocardial dilatation has evolved. The aim of the present study was to compare the long-term course of congestive heart failure due to alcoholic and idiopathic dilated cardiomyopathy. Of 75 patients with overt congestive heart failure, 23 had alcoholic cardiomyopathy and were compared to 52 patients with idiopathic cardiomyopathy. The mean age was 48 ± 12 years. Despite medical therapy, heart failure class New York Heart Association III-IV was present in 52% of patients with alcoholic and 47% of patients with idiopathic cardiomyopathy (not significant). Their mean left ventricular ejection fraction was 30 ± l2% vs 28 ± 12% and left ventricular end-diastolic volumes were 264 ± 125 ml and 254 ± 100 ml respectively (not significant). Overall survival at 1, 5 and 10 years was l00%, 81% and 81% for the group with alcoholic dilated cardiomyopathy and 89%, 48% and 30% for the group with idiopathic cardiomyopathy, respectively (P=0·041 and the difference was even greater for transplant-free survival P=0·005 Clinical and invasive signs of left and right heart failure as well as left ventricular dimensions were predictive of a fatal outcome; however, symptom duration and left ventricular volumes were only predictive in patients with idiopathic cardiomyopathy, suggesting that in the two patient groups different mechanisms may lead to death. Mortality in patients with severe congestive heart failure and left ventricular dilatation due to alcoholic cardiomyopathy is significantly lower than that in patients with idiopathic cardiomyopathy and similar degrees of heart failure. Thus, despite structural changes mherent in marked left ventricular dilatation, disease progression in alcoholic dilated cardiomyopathy is different from that in idiopathic cardiomyopathy and thus may have implications for the choice of therap
Winterzwiebeln: Anbau IP oder Bio
Bei der Sorte Radar führt das Stecken von «grossen» Steckzwiebeln zu einem höheren Ertrag in beiden Anbausystemen, IP und Bio. Auch wird der Anteil an grossen und Metzgerzwiebeln gesteigert, besonders ausgeprägt unter IP-Bedingungen. Dies ging einher mit einer leichten Zunahme (<6%) der Schossneigung bei «grossen» Steckzwiebeln und frühem Stecktermin
- …
