43 research outputs found
Global entanglement and quantum criticality in spin chains
Entanglement in quantum XY spin chains of arbitrary length is investigated
via a recently-developed global measure suitable for generic quantum many-body
systems. The entanglement surface is determined over the phase diagram, and
found to exhibit structure richer than expected. Near the critical line, the
entanglement is peaked (albeit analytically), consistent with the notion that
entanglement--the non-factorization of wave functions--reflects quantum
correlations. Singularity does, however, accompany the critical line, as
revealed by the divergence of the field-derivative of the entanglement along
the line. The form of this singularity is dictated by the universality class
controlling the quantum phase transition.Comment: 4 pages, 2 figure
Evaluation of a Rapid Dipstick (Crystal VC) for the Diagnosis of Cholera in Zanzibar and a Comparison with Previous Studies
BackgroundThe gold standard for the diagnosis of cholera is stool culture, but this requires laboratory facilities and takes at least 24 hours. A rapid diagnostic test (RDT) that can be used by minimally trained staff at treatment centers could potentially improve the reporting and management of cholera outbreaks.MethodsWe evaluated the Crystal VC™ RDT under field conditions in Zanzibar in 2009. Patients presenting to treatment centers with watery diarrhea provided a stool sample for rapid diagnostic testing. Results were compared to stool culture performed in a reference laboratory. We assessed the overall performance of the RDT and evaluated whether previous intake of antibiotics, intravenous fluids, location of testing, and skill level of the technician affected the RDT results.ResultsWe included stool samples from 624 patients. Compared to culture, the overall sensitivity of the RDT was 93.1% (95%CI: 88.7 to 96.2%), specificity was 49.2% (95%CI: 44.3 to 54.1%), the positive predictive value was 47.0% (95%CI: 42.1 to 52.0%) and the negative predictive value was 93.6% (95%CI: 89.6 to 96.5%). The overall false positivity rate was 50.8% (213/419); fieldworkers frequently misread very faint test lines as positive.ConclusionThe observed sensitivity of the Crystal VC RDT evaluated was similar compared to earlier versions, while specificity was poorer. The current version of the RDT could potentially be used as a screening tool in the field. Because of the high proportion of false positive results when field workers test stool specimens, positive results will need to be confirmed with stool culture
Extraluminal gastrointestinal stromal tumour (GIST) located at the splenic flexure of the colon
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A large number of hypothetical proteins are differentially expressed during stress in desulfovibrio vulgaris
Human Capital Attainment and Gender Empowerment: The Kerala Paradox
The State of Kerala in southwestern India shows the highest gender development index in the country. Despite having the highest literacy rate and educational achievements of women, the suicide rate among females is very high, and domestic violence committed against women is increasing every year in Kerala. This article attempts to analyze the demographic, social, and cultural changes that are occurring in order to understand this apparent paradox of high human capital attainment and high violence and suicides experienced by women in Kerala. Copyright (c) 2007 by the Southwestern Social Science Association.
Silica Sulphuric Acid: An Efficient and Recyclable Catalyst for the Synthesis of β‐Acetamido Ketones in Single Pot
Jejunal GIST with extramural hemangiomatous component presenting as an obscure lower GI bleed: a case report
Opening the terahertz window on the OSIRIS spectrometer
A cooled and mechanically retractable beryllium filter has been installed and commissioned on the low-energy OSIRIS spectrometer at ISIS. This instrument development extends the energy-transfer range of the spectrometer up to ca. 20 meV (∼ 5 THz), leading to an excellent resolution at THz frequencies and substantial gains in detected flux relative to existing capabilities on the neighbouring IRIS spectrometer. Herein, we provide a concise account of this new capability for high-resolution neutron spectroscopy in the THz domain, as well as outline a number of ongoing and potential scientific opportunities in condensed-matter physics, chemistry, and materials science