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A Hybrid Method for Accelerated Simulation of Coulomb Collisions in a Plasma
No full textIf the collisional time scale for Coulomb collisions is comparable to the characteristic time scales for a plasma, then simulation of Coulomb collisions may be important for computation of kinetic plasma dynamics. This can be a computational bottleneck because of the large number of simulated particles and collisions (or phase-space resolution requirements in continuum algorithms), as well as the wide range of collision rates over the velocity distribution function. This paper considers Monte Carlo simulation of Coulomb collisions using the binary collision models of Takizuka & Abe and Nanbu. It presents a hybrid method for accelerating the computation of Coulomb collisions. The hybrid method represents the velocity distribution function as a combination of a thermal component (a Maxwellian distribution) and a kinetic component (a set of discrete particles). Collisions between particles from the thermal component preserve the Maxwellian; collisions between particles from the kinetic component are performed using the method of or Nanbu. Collisions between the kinetic and thermal components are performed by sampling a particle from the thermal component and selecting a particle from the kinetic component. Particles are also transferred between the two components according to thermalization and dethermalization probabilities, which are functions of phase space
The use of motivational interviewing techniques to enhance the efficacy of guided self-help behavioral weight loss treatment
No full textThis study assessed whether motivational interviewing (MI), applied as part of a standard guided self-help (GSH) behavioral weight loss treatment, reduced attrition rate and improved participant weight loss and other eating-related and general psychological measures. The study also included assessments based on two theories of motivated behavior, to assess whether these measures predicted treatment outcome and whether MI increased participant motivation. Thirty-nine overweight patients (7 males, 32 females) were randomized to receive either 6 sessions of traditional GSH and 2 traditional motivation-focused sessions (GSH); or 6 GSH sessions and 2 sessions utilizing an MI approach to motivation (MI/GSH). In intention-to-treat and completer analyses, significant differences were found in the areas of eating concern and control over eating, favoring MI/GSH. Between-group effect size estimates indicated a small to medium advantage for MI/GSH over GSH in weight loss, as well as on a number of secondary eating-related measures. Analyses of motivational measures indicated no significant differences by treatment group, but suggested that individuals who were more confident in their abilities to change and endorsed more extrinsic reasons for change lost more weight than other participants. Implications and future directions are discussed.Ph.D.Includes bibliographical references (p. 65-70)
A high-precision miniaturized rotating coil transducer for magnetic measurements
No full textA miniaturized Printed Circuit Board (PCB) sensing coil, jointly developed by CERN and Fermilab for measuring the field of small-gap (less than 10 mm) accelerator magnets, is illustrated. A sensing coil array, with a scheme for compensating the main field when measuring the harmonic error components, hosted on a synthetic sapphire-based transducer, is presented. Key innovating features are (i) very-small size, both for the sensing coil array (thickness of 1.380 mm) and for the transducer (overall diameter of 7.350 mm), (ii) metrological performance, namely accuracy (more than five times better than state of the art), and 1-sigma repeatability (ten times better on harmonics with amplitude less than 100 ppm), and (iii) manufacturing technology of both the coil array (13 double layers aligned within 10 m), and the sapphire support (concentricity, the most important uncertainty source for rotating coils, 3 m of uncertainty, namely one order of magnitude better than fiberglass support). After stating the measurement problem, the design of the transducer and a case study of a two-layer PCB sensor array are illustrated. Then, the prototyping and quality control of both the sensor and the transducer are discussed. Furthermore, the calibration and the results obtained with a prototype setup at Fermilab are presented. Finally, in the appendix, the theory of the rotating coil, the sensor geometry, and the harmonic compensation are briefly reviewed for the reader easiness
Identification of a syndrome of nocturnal restlessness in Parkinson's disease using a novel visual analogue sleep scale
No full textAbdominal splenosis and its differential diagnoses: What the radiologist needs to know
No full textSplenosis is a benign acquired condition characterized by the presence of heterotopic viable splenic tissue in other organs or within cavities such as peritoneum, retroperitoneum, or thorax after splenic trauma or surgery. Abdominal splenosis is often an incidental finding and computed tomography and magnetic resonance usually allow a confident diagnosis. The typical enhancement that parallels the spleen is a useful hallmark of splenosis. Splenic implants lack contrast uptake in the hepatobiliary phase and show high signal at high b-values on diffusion-weighted images. In some cases splenosis may mimic malignant and benign conditions in the peritoneum as well as in hollow and parenchymal abdominal organs and further investigations – including scintigraphy with Tc99m-labelled heat-denatured red blood cells or biopsy – are sometimes required in challenging cases. This pictorial essay reviews the imaging presentation and potential differential diagnosis of splenosis according to the site of implantation. A prompt and accurate radiological diagnosis of splenosis can avoid unnecessary biopsy or surgery
Morbidity associated with anomalous origin of the left circumflex coronary artery from the right aortic sinus.
No full textAnomalous origin of the left circumflex (LC) coronary artery from the right sinus of Valsalva is the most common coronary anomaly and, generally, is considered to be benign.Nevertheless, myocardial infarction or sudden death in young patients with this coronary anomaly has infrequently been described.We report 2 cases of anomalous origin of the LC coronary artery from right aortic sinus, free of atherosclerotic obstructive lesions, presenting clinically with either myocardial infarction or effort angina
Identification of a syndrome of nocturnal restlessness in Parkinson's disease using a novel visual analogue sleep scale
No full textCase report Open Access Liver abscess caused by Klebsiella pneumoniae: two case reports
No full textThis is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
S-Detect characterization of focal solid breast lesions: a prospective analysis of inter-reader agreement for US BI-RADS descriptors
No full textBackground: To assess inter-reader agreement for US BI-RADS descriptors using S-Detect: a computer-guided decision-making software assisting in US morphologic analysis. Methods: 73 solid focal breast lesions (FBLs) (mean size: 15.9 mm) in 73 consecutive women (mean age: 51 years) detected at US were randomly and independently assessed according to the BI-RADS US lexicon, without and with S-Detect, by five independent reviewers. US-guided core-biopsy and 24-month follow-up were considered as standard of reference. Kappa statistics were calculated to assess inter-operator agreement, between the baseline and after S-Detect evaluation. Agreement was graded as poor (≤ 0.20), moderate (0.21–0.40), fair (0.41–0.60), good (0.61–0.80), or very good (0.81–1.00). Results: 33/73 (45.2%) FBLs were malignant and 40/73 (54.8%) FBLs were benign. A statistically significant improvement of inter-reader agreement from fair to good with the use of S-Detect was observed for shape (from 0.421 to 0.612) and orientation (from 0.417 to 0.7) (p < 0.0001) and from moderate to fair for margin (from 0.204 to 0.482) and posterior features (from 0.286 to 0.522) (p < 0.0001). At baseline analysis isoechoic (0.0485) and heterogeneous (0.1978) echo pattern, microlobulated (0.1161) angular (0.1204) and spiculated (0.1692) margins and combined pattern (0.1549) for posterior features showed the worst agreement rate (poor). After S-Detect evaluation, all variables but isoechoic pattern showed an agreement class upgrade with a statistically significant improvement of inter-reader agreement (p < 0.0001). Conclusions: S-Detect significantly improved inter-reader agreement in the assessment of FBLs according to the BI-RADS US lexicon but evaluation of margin and echo pattern needs to be further improved, particularly isoechoic pattern
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