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

Opening the terahertz window on the OSIRIS spectrometer

4 pags., 6 figs. -- QENS/WINS 2014 - 11th International Conference on Quasielastic Neutron Scattering and 6th International Workshop on Inelastic Neutron SpectrometersA 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.The authors gratefully acknowledge the UK Science & Technology Facilities Council for financial support and access to beam time at ISIS

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

A Short Communication On Some Aspects Of Underfive Clinic Services At GODA Periurban Community

A longitudinal study on underfives of a periurban community was undertaken to study the magnitude of the problem and some important related factors. The extent of utilization and role of repeated clinic visits in the prevention of under nutrition was also studied. Results revealed that prevalence of under nutrition was 45.6% being maximum in the age group of 3-5 years and in males. Recurrent diarrhoea, dysentery and worm infestations were important reasons probably responsible for under- nutrition. Families with more than three siblings had a greater prevalence of undernourished under fives. 56.79% had more than two visits to the clinic. Repeated clinic visits could not improve the nutritional status of the underfives

METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS CARRIAGE AMONG HEALTH-CARE PROFESSIONALS OF A TERTIARY CARE HOSPITAL

 Objective: The aim of this study was to find the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carrier status in anterior nares and hands of health-care professionals working in orthopedic wards of a tertiary care hospital and to decolonize them to reduce spread of MRSA to their patients.Methods: The study was conducted in a super specialty, tertiary care teaching hospital. The samples were collected from anterior nares, palm, web spaces, and fingertips of 140 health-care professionals (48 doctors, 74 nurses, and 18 technicians) working in orthopedic wards using sterile pre-moistened swabs. MRSA carrier status was identified by Kirby-Bauer disc diffusion method.Result: Most (76.4%) of the health-care professionals were <30 years of age and 51% were male. MRSA in anterior nares of doctors was 4.3%, nurses 1.4%, and technicians 0.7% and none had MRSA in their hands. Methicillin-sensitive Staphylococcus aureus (MSSA) growth was more among nurses (nurses - 5.7%, doctors - 2.1%, and technicians - 1.4%) in anterior nares. In addition, 1.4% nurses' hands were colonized with MSSA. Both MRSA and MSSA carriers were decolonized effectively and repeat sampling showed no growth.Conclusion: Health-care professionals have a greater chance of transmitting MRSA to patients and orthopedic patients are more susceptible for infection. Although MRSA carrier status was not very high among orthopedic health-care professionals compared to previous studies, it cannot be ignored. Nasal mupirocin and bath with chlorhexidine soap were effective in decolonization. Periodic screening and treatment of colonizers would help in elimination of MRSA carriage