Erratum: ‘‘Evidence for field enhanced electron capture by EL2 centers in semi‐insulating GaAs and the effect on GaAs radiation detectors’’ [J. Appl. Phys. 75, 7910 (1994)]

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69985/2/JAPIAU-77-3-1331-1.pd

Evidence for field enhanced electron capture by EL2 centers in semi‐insulating GaAs and the effect on GaAs radiation detectors

The performance of Schottky contact semiconductor radiation detectors fabricated from semi‐insulating GaAs is highly sensitive to charged impurities and defects in the material. The observed behavior of semi‐insulating GaAs Schottky barrier alpha particle detectors does not match well with models that treat the semi‐insulating material as either perfectly intrinsic or as material with deep donors (EL2) of constant capture cross section compensated with shallow acceptors. We propose an explanation for the discrepancy based on enhanced capture of electrons by EL2 centers at high electric fields and the resulting formation of a quasineutral region in the GaAs. Presented is a simple model including field enhanced electron capture which shows good agreement with experimental alpha particle pulse height measurements.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71231/2/JAPIAU-75-12-7910-1.pd

Utilization of Upper Endoscopy for Surveillance of Gastric Ulcers in the United States

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73657/1/j.1572-0241.2008.01945.x.pd

Evidence for field enhanced electron capture by EL2 centers in semi-insulating GaAs and the effect on GaAs radiation detectors

The performance of Schottky contact semiconductor radiation detectors fabricated from semi-insulating GaAs is highly sensitive to charged impurities and defects in the material. The observed behavior of semi-insulating GaAs Schottky barrier alpha particle detectors does not match well with models that treat the semi-insulating material as either perfectly intrinsic or as material with deep donors (EL2) of constant capture cross section compensated with shallow acceptors. We propose an explanation for the discrepancy based on enhanced capture of electrons by EL2 centers at high electric fields and the resulting formation of a quasineutral region in the GaAs. Presented is a simple model including field enhanced electron capture which shows good agreement with experimental alpha particle pulse height measurements

A multicenter, prospective, randomized comparison of a novel signal transmission capsule endoscope to an existing capsule endoscope.

BACKGROUND: MiroCam, a capsule endoscope, uses a novel transmission technology, electric-field propagation, which uses the human body as a conduction medium for data transmission. OBJECTIVE: To compare the ability of the MiroCam (MC) and PillCam (PC) to identify sources of obscure GI bleeding (OGIB). DESIGN: Prospective, multicenter, comparative study. SETTING: Six academic hospitals. PATIENTS: A total of 105 patients with OGIB. INTERVENTION: Patients ingested both the MC and PC capsules sequentially in a randomized fashion. MAIN OUTCOME MEASUREMENTS: Concordance of rates in identifying a source of OGIB, operational times, and rates of complete small-bowel examination. RESULTS: Data analysis resulted in 43 (48%) abnormal cases identifying a source of OGIB by either capsule. Twenty-four cases (55.8%) were positive by both capsules. There was negative agreement in 46 of 58 cases (79.3%). The κ index was 0.547 (χ(2) = 1.32; P = .36). In 12 cases, MC positively identified a source that was not seen on PC, whereas in 7 cases, PC positively identified a source that was not seen on MC. MC had a 5.6% higher rate of detecting small-bowel lesions (P = .54). MC captured images at 3 frames per second for 11.1 hours, and PC captured images at 2 frames per second for 7.8 hours (P \u3c .0001). Complete small-bowel examination was achieved in 93.3% for MC and 84.3% for PC (P = .10). LIMITATIONS: Readers were not blinded to the particular capsule they were reading. CONCLUSION: A positive diagnostic finding for OGIB was identified by either capsule in 48% of cases. The concordance rate between the 2 capsules was comparable to that of prior studies in identifying sources of small-bowel bleeding. The longer operational time of the MC may result in higher rates of complete small-bowel examination, which may, in turn, translate into a higher rate of detecting small-bowel lesions. (Clinical trial registration number: NCT00878982.)

Sport and British Jewish identity

This article examines the relationship between sport and Jewish identity. The experiences of Jewish people have rarely been considered in previous sport-related research which has typically focused on ‘Black’ and South Asian individuals, sports clubs, and organisations. Drawing on data generated from interviews ( n = 20) and focus groups ( n = 2) with individuals based in one British city, this article explores how their Jewish identity was informed, and shaped by, different sports activities and spaces. This study’s participants were quick to correct the idea that sport was alien to Jewish culture and did not accept the stereotype that ‘Jews don’t play sport’. The limited historical research on sport and Jewish people and the ongoing debates around Jewish identity are noted before exploring the role of religion and the suggestion that Jewish participation in sport is affected by the Shabbat (sabbath). Participants discussed how sports clubs acted as spaces for the expression and re/affirmation of their Jewish identity, before they reflected on the threats posed to the wider Jewish community by secularism, assimilation, and antisemitism. The article concludes by discussing how the sporting experiences of the study’s British Jewish participants compare with the experiences of individuals from other ethnic minority communities

Durability of Radiofrequency Ablation in Barrett's Esophagus With Dysplasia

Radiofrequency ablation (RFA) can eradicate dysplasia and intestinal metaplasia in patients with dysplastic Barrett’s esophagus (BE), and reduce rates of esophageal adenocarcinoma. We assessed long-term rates of eradication, durability of neosquamous epithelium, disease progression, and safety of RFA in patients with dysplastic BE

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children