Search results for "value"
showing 10 items of 5321 documents
An upper bound for nonlinear eigenvalues on convex domains by means of the isoperimetric deficit
2010
We prove an upper bound for the first Dirichlet eigenvalue of the p-Laplacian operator on convex domains. The result implies a sharp inequality where, for any convex set, the Faber-Krahn deficit is dominated by the isoperimetric deficit.
On dependence of sets of functions on the mean value of their elements
2009
The paper considers, for a given closed bounded set M ⊂ R m and K = (0,1) n ⊂ R n , the set M = {h ϵ L2 (K;R m ) | h(x) ϵ M a.e.x ϵ K} and its subsets It is shown that, if a sequence {hk } ⊂ coM converges to an element hk ϵ M(hk ) there is h‘k ϵ M(ho ) such that h'k - hk → 0 as k → ∞ . If, in addition, the set M is finite or M is the convex hull of a finite set of elements, then the multivalued mapping h → M(h) is lower semicontinuous on coM. First published online: 14 Oct 2010
Thermally Induced Structural Modification of Silica Nanoparticles Investigated by Raman and Infrared Absorption Spectroscopies
2010
We report an experimental investigation by Raman and infrared (IR) absorption spectroscopies on the structural modifications induced by isochronal thermal treatments on amorphous SiO2 nanoparticles (fumed silica). In particular, three different commercial types of this material, characterized by particle mean diameters of 7, 14, and 40 nm, were subjected to thermal treatments from 100 up to 1000 °C. We found that some properties of fumed silica, such as the SiOSi mean bond angle, ring size distribution, and surface adsorbed water content, are drastically different from those of common bulk silica materials and intimately related to the particles' dimension. The SiOSi mean bond angle, probed…
Italian multicenter, prospective study to evaluate the negative predictive value of 16- and 64-slice MDCT imaging in patients scheduled for coronary …
2009
This was a prospective, multicenter study designed to evaluate the utility of MDCT in the diagnosis of coronary artery disease (CAD) in patients scheduled for elective coronary angiography (CA) using different MDCT systems from different manufacturers. Twenty national sites prospectively enrolled 367 patients between July 2004 and June 2006. Computed tomography (CT) was performed using a standardized/optimized scan protocol for each type of MDCT system (> or =16 slices) and compared with quantitative CA performed within 2 weeks of MDCT. A total of 284 patients (81%) were studied by 16-slice MDCT systems, while 66 patients (19%) by 64-slice MDCT scanners. The primary analysis was on-site/off…
Prognostic outcome of routine clinical noninvasive Multidetector row Computed Tomography Coronary Angiography in Patients with suspected coronary art…
2011
The aim of the study was to assess the prognostic value of multidetector-row CT coronary angiography (MDCT-CA) in patients with suspected coronary artery disease (CAD) in a routine clinical context.A total of 125 patients (82 men, age 57.4±10.3 years) with suspected CAD underwent MDCT-CA. All patients were assessed for cardiovascular risk factors, symptoms and coronary calcium score. A 2-year follow-up study for the occurrence of major adverse cardiac events was performed.According to the Morise pretest score, 76 patients (60.8%) were at intermediate risk. Patients with suspected CAD presented the following prognostic outcome (p0.0001): in 41 patients with normal coronary arteries at MDCT-C…
The German CPU Registry: Dyspnea independently predicts negative short-term outcome in patients admitted to German Chest Pain Units.
2015
While dyspnea is a common symptom in patients admitted to Chest Pain Units (CPUs) little is known about the impact of dyspnea on their outcome. The purpose of this study was to evaluate the impact of dyspnea on the short-term outcome of CPU patients.We analyzed data from a total of 9169 patients admitted to one of the 38 participating CPUs in this registry between December 2008 and January 2013. Only patients who underwent coronary angiography for suspected ACS were included. 2601 patients (28.4%) presented with dyspnea.Patients with dyspnea at admission were older and frequently had a wide range of comorbidities compared to patients without dyspnea. Heart failure symptoms in particular wer…
Improving diagnostic accuracy of MDCT coronary angiography in patients with mild heart rhythm irregularities using ECG editing
2006
OBJECTIVE. The objective of our study was to compare diagnostic accuracy of MDCT coronary angiography in a population of patients with mild heart rhythm irregularities before and after editing the ECG. SUBJECTS AND METHODS. Thirty-eight patients who underwent MDCT coronary angiography and conventional coronary angiography were enrolled in the study. The inclusion criterion was the presence of mild heart rhythm irregularities (i.e., premature beats; atrial fibrillation; mistriggering; or low heart rate, defined as 40 beats per minute or less) during the scan. All patients underwent MDCT with the following parameters: 16 detectors; collimation, 0.75 mm; gantry rotation time, 375 msec; 120 kV;…
Prognostic value of Morise clinical score, calcium score and computed tomography coronary angiography in patients with suspected or known coronary ar…
2011
Our aim was to determine the prognostic value of computed tomography coronary angiography (CTCA), coronary artery calcium scoring (CACS) and Morise clinical score in patients with known or suspected coronary artery disease (CAD). A total of 722 patients (480 men; 62.7 +/- 10.9 years) who were referred for further cardiac evaluation underwent CACS and contrast-enhanced CTCA to evaluate the presence and severity of CAD. Of these, 511 (71%) patients were without previous history of CAD. Patients were stratified according to the Morise clinical score (low, intermediate, high), to CACS (0-10, 11-100, 101-400, 401-1,000, > 1,000) and to CTCA (absence of CAD, nonsignificant CAD, obstructive CAD…
Right coronary artery arising from pulmonary trunk: assessment with conventional coronary angiography and multislice computed tomography coronary ang…
2009
We present a case of a 59-year-old man who was admitted to the hospital because of atypical chest pain and dyspnea. Conventional coronary angiography showed an anomalous origin of the right coronary artery from the pulmonary trunk. The patient underwent multislice computed tomography in order to clarify the origin and course of the anomalous vessel. The aim of this report is to emphasize the role of multislice computed tomography as an accurate noninvasive imaging tool in the evaluation of coronary artery anomalies.
Les effets des liens personnels interconseils sur la performance de l'entreprise : une analyse comparée entre France et Allemagne
2010
Obgleich das Thema „personelle Unternehmensverflechtungen über den Aufsichtsrat“ re-gelmäßig im Fokus öffentlicher Diskussionen steht – wobei in der Regel eine negative Wirkung der Mandatekumulation auf die Kontrolleffizienz des Überwachungsgremiums und damit letztlich auf die Unternehmensperformance unterstellt wird –, zeigt eine Analyse der empirischen Litera-tur, dass insbesondere in Kontinentaleuropa eine klare Schlussfolgerung hinsichtlich der Wirkung von Mehrfachmandaten auf die Wertschöpfung für die Aktionäre nicht möglich ist. Ursache für die starke Divergenz der Ergebnisse scheint sowohl die Verwendung verschiedener theoretischer Erklärungsmodelle als auch die Mobilisierung untersc…