The static electric polarizability of a particle bound by a finite potential well

In this paper we derive an expression for the static electric polarizability of a particle bound by a finite potential well without the explicit use of the continuum states in our calculations. This will be accomplished by employing the elegant Dalgarno-Lewis perturbative technique.Comment: 14 Pages, 2 Table

A bizarre foreign body in the appendix: A case report

Foreign bodies are rare causes of appendicitis and, in most cases, ingested foreign bodies pass through the alimentary tract asymptomatically. However, ingested foreign bodies may sometimes remain silent within the appendix for many years without an inflammatory response. Despite the fact that cases of foreign-body-induced appendicitis have been documented, sharp and pointed objects are more likely to cause perforations and abscesses, and present more rapidly after ingestion. Various materials, such as needles and drill bits, as well as organic matter, such as seeds, have been implicated as causes of acute appendicitis. Clinical presentation can vary from hours to years. Blunt foreign bodies are more likely to remain dormant for longer periods and cause appendicitis through obstruction of the appendiceal lumen. We herein describe a patient presenting with a foreign body in his appendix which had been swallowed 15 years previously. The contrast between the large size of the foreign body, the long clinical history without symptoms and the total absence of any histological inflammation was notable. We suggest that an elective laparoscopic appendectomy should be offered to such patients as a possible management optio

Density correlations in ultracold atomic Fermi gases

We investigate density fluctuations in a coherent ensemble of interacting fermionic atoms. Adapting the concept of full counting statistics, well-known from quantum optics and mesoscopic electron transport, we study second-order as well as higher-order correlators of density fluctuations. Using the mean-field BCS state to describe the whole interval between the BCS limit and the BEC limit, we obtain an exact expression for the cumulant-generating function of the density fluctuations of an atomic cloud. In the two-dimensional case, we obtain a closed analytical expression. Poissonian fluctuations of a molecular condensate on the BEC side are strongly suppressed on the BCS side. The size of the fluctuations in the BCS limit is a direct measure of the pairing potential. We also discuss the BEC-BCS crossover of the third cumulant and the temperature dependence of the second cumulant.Comment: 4 pages, 4 figures. To appear in Phys. Rev. A. New calculation of the bin statistics of a free Bose gas; updated and extended bibliograph

Experimental evaluation of a localization algorithm for multiple acoustic sources in reverberating environments

Publication in the conference proceedings of EUSIPCO, Florence, Italy, 200

New insight into the genomic structure of dog T cell receptor beta (TRB) locus inferred from expression analysis

Here is an updated report on the genomic organization of T cell receptor beta (TRB) locus in the domestic dog (Canis lupus familiaris) as inferred from comparative genomics and expression analysis. The most interesting results we found were a second TRBD–J–C cluster, which is absent from the reference genome sequence, and the annotation of two additional TRBV genes. In dogs, TRB locus consists of a library of 37 TRBV genes positioned at the 50 end of two in tandem aligned D–J–C gene clusters, each composed of a single TRBD, 6 TRBJ and one TRBC genes, followed by a single TRBV gene with an inverted transcriptional orientation. The TRB genes are distributed in less than 300 kb, making the canine locus, one of the smaller mammalian TRB locus studied so far. The small size may be ascribed to reduced gene duplication occurrences and a lower density of total interspersed repeats compared to humans and mice. Despite the low TRBV gene content, a large and diversified beta chain repertoire is displayed in the dog peripheral blood. A full usage of TRBV and TRBJ genes, including pseudogenes, and a high level of allelic polymorphism contribute to generate diversity. Finally, this study suggests that the overall TRB locus organization is evolutionarily conserved supporting the dog as a highly suited model system for immune development and diseases

Vertebral Body Stapling versus Bracing for Patients with High-Risk Moderate Idiopathic Scoliosis.

Purpose. We report a comparison study of vertebral body stapling (VBS) versus a matched bracing cohort for immature patients with moderate (25 to 44°) idiopathic scoliosis (IS). Methods. 42 of 49 consecutive patients (86%) with IS were treated with VBS and followed for a minimum of 2 years. They were compared to 121 braced patients meeting identical inclusion criteria. 52 patients (66 curves) were matched according to age at start of treatment (10.6 years versus 11.1 years, resp. [P = 0.07]) and gender. Results. For thoracic curves 25-34°, VBS had a success rate (defined as curve progressio

The influence of direct instruction on asynchronous educational discussions

Title from PDF of title page (University of Missouri--Columbia, viewed on May 25, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Joi L. MooreVita."December 2011"Ph. D. University of Missouri-Columbia 2011.Online learning is an important and rapidly growing area, and asynchronous discussions are a vital component of online courses. This doctoral study examined the influence of discussion moderator messages, specifically messages with direct instruction content, had on those discussions. This study obtained data from content analysis of course discussions. The subjects for this study were the instructor and all 15 students enrolled in a fully-online graduate course at a large, public university medical center. The study found that the direct instruction content of an instructor message influenced students replying to that instructor message as well as students reading other student replies to that instructor message. The current study found that the direct instruction content of the instructor message may also influence students reading an instructor message and students responding to other replies to that instructor message. Instructors can use these findings to more effectively moderate their online discussions.Includes bibliographical reference

MRI analysis for Hippocampus segmentation on a distributed infrastructure

Medical image computing raises new challenges due to the scale and the complexity of the required analyses. Medical image databases are currently available to supply clinical diagnosis. For instance, it is possible to provide diagnostic information based on an imaging biomarker comparing a single case to the reference group (controls or patients with disease). At the same time many sophisticated and computationally intensive algorithms have been implemented to extract useful information from medical images. Many applications would take great advantage by using scientific workflow technology due to its design, rapid implementation and reuse. However this technology requires a distributed computing infrastructure (such as Grid or Cloud) to be executed efficiently. One of the most used workflow manager for medical image processing is the LONI pipeline (LP), a graphical workbench developed by the Laboratory of Neuro Imaging (http://pipeline.loni.usc.edu). In this article we present a general approach to submit and monitor workflows on distributed infrastructures using LONI Pipeline, including European Grid Infrastructure (EGI) and Torque-based batch farm. In this paper we implemented a complete segmentation pipeline in brain magnetic resonance imaging (MRI). It requires time-consuming and data-intensive processing and for which reducing the computing time is crucial to meet clinical practice constraints. The developed approach is based on web services and can be used for any medical imaging application

Complex-Valued Physics-Informed Neural Network for Near-Field Acoustic Holography

We present a novel approach to Near-field Acoustic Holography (NAH) with the introduction of the Complex-Valued Kirchhoff-Helmholtz Convolutional Neural Network (CV-KHCNN). Our study focuses on analyzing Complex-Valued Neural Networks (CVNNs) in the application of NAH scenario. We compare the performance between CV-KHCNN and its equivalent Real-Valued Neural Networks (RVNNs). Moreover, different complex activation functions are evaluated for CV-KHCNN. The results emphasize the effectiveness of CVNNs in tackling NAH challenges and highlight the suitability of Cardioid as the activation function for CVNNs. This discovery underscores the promising contributions of CVNNs to the field of NAH. T-distributed Stochastic Neighbor Embedding (t-SNE) is further adopted to visualize the features of the embedding layer. The results show that even without prior knowledge of the vibrations, CV-KHCNN demonstrates the capability to distinguish between different boundary conditions (BCs) and mode shapes