295 research outputs found
New Forms of BRST Symmetry on a Prototypical First-Class System
We scrutinize the many known forms of BRST symmetries, as well as some new
ones, realized within a prototypical first-class system. Similarities and
differences among ordinary BRST, anti-BRST, dual-BRST and anti-dual-BRST
symmetries are highlighted and discussed. We identify a precise
discrete group of symmetries of the ghost
sector, responsible for connecting the various forms of BRST transformations.
Considering a Hamiltonian approach, those symmetries can be interrelated by
canonical transformations among ghost variables. However, the distinguished
characteristic role of the dual BRST symmetries can be fully appreciated within
a gauge-fixed Lagrangian viewpoint. New forms of BRST symmetries are given, a
set generalizing particular ones previously reported in the literature as well
as a brand new unprecedented set. The featured gauge invariant prototypical
first-class system encompasses an extensive class of physical models and sheds
light on previous controversies in the current quantum field theory literature.Comment: 12 pages, No Figs, Late
Physiological and behavioral risk factors of type 2 diabetes mellitus in rural India
BACKGROUND: The dynamics of physiological and behavioral risk factors of diabetes in rural India is poorly understood. Using data from a health and demographic surveillance site of Birbhum district in West Bengal, India, this study aims to assess the risk factors associated with type 2 diabetes mellitus. RESEARCH DESIGN AND METHODS: A total of 7674 individuals aged ≥18 years participated in a cross-sectional study. Venous plasma glucose method was used for measuring and reporting glucose concentrations in blood, categorized as individuals with diabetes, pre-diabetes or impaired, and normoglycemic. Aside from a set of physiological and behavioral risk factors, a range of socioeconomic confounders of diabetes was computed. Bivariate analysis with χ(2) test, and multivariate ordered logit regression methods were deployed to attain the study's objective. RESULTS: Overall 2.95% and 3.34% of study participants were diagnosed as individuals with diabetes and pre-diabetes or impaired, respectively. Compared to the poorest, the richest have higher probability (β: 0.730; 95% CI 0.378 to 1.083) of being diagnosed with diabetes. As compared to people with normal body mass index, overweight/obese people are more prone to being diagnosed with diabetes (β: 0.388; 95% CI 0.147 to 0.628). With a decreasing level of physical activity, people are more likely to be diagnosed with diabetes. CONCLUSIONS: To curb the level of diabetes, this study recommends a culturally sensitive, focused intervention for the adoption of physical activity with more traditional dietary practices, to control the level of overweight/obesity. Attention should be paid to relatively older patients with diabetes or adults with pre-diabetes
New forms of BRST symmetry in rigid rotor
We derive the different forms of BRST symmetry by using the
Batalin-Fradkin-Vilkovisky formalism in a rigid rotor. The so called
"dual-BRST" symmetry is obtained from usual BRST symmetry by making a canonical
transformation in the ghost sector. On the other hand, a canonical
transformation in the sector involving Lagrange multiplier and its
corresponding momentum leads to a new form of BRST as well as dual-BRST
symmetry.Comment: 10 Pages, revtex, No Fig
Carriage Prevalence of Carbapenem Resistant Enterobacteriaceae in Stool Samples: A Surveillance Study
BackgroundWith more people being exposed to antibiotics, intestinal microflora faces constant pressure of antibiotic selection, which has resulted in the emergence of multidrug resistant strains. This may pose a severe problem as intestinal Enterobacteriaceae members are commonly implicated in human infections. Â AimsThis surveillance study was undertaken to investigate the carriage of carbapenem-resistant Enterobacteriaceae (CRE) in the gastrointestinal tract among patients attending the outpatient clinic in a tertiary care center of East Delhi, India. MethodWe performed a prospective surveillance study to screen 242 Enterobacteriaceae isolates for carbapenemase production from the stool samples of 123 outpatients attending a tertiary care hospital in East Delhi over a four-month period. ResultsTwenty-four (9.9 per cent) isolates demonstrated carbapenemase activity among 242 screened Enterobacteriaceae isolates. Four stool samples had two isolates of different species, both eliciting this feature and therefore indicating presence of multiple carbapenem-resistant Enterobacteriaceae (CRE) isolates in a single sample. ConclusionScreening for carriage of CRE in stools of patients undergoing elective or emergency gastrointestinal surgical procedures, with haematological malignancies taking chemotherapy, or those planned for bone marrow transplantation can guide clinicians about gut colonisation of multidrug-resistant Enterobacteriaceae as these groups of patients are at risk of possible endogenous infection.
Relating the generating functionals in field/antifield formulation through finite field dependent BRST transformation
We study the field/antifield formulation of pure Yang Mills theory in the
framework of finite field dependent BRST transformation. We show that the
generating functionals corresponding to different solutions of quantum master
equation are connected through the finite field dependent BRST transformations.
We establish this result with the help of several explicit examples.Comment: Revtex4, 18 pages, No figs, Accepted in Eur. Phys. J
Noncommutative Dirac oscillator in an external magnetic field
We show that (2+1) dimensional noncommutative Dirac oscillator in an external
magnetic field is mapped onto the same but with reduced angular frequency in
absence of magnetic field. We construct the relativistic Landau levels by
solving corresponding Dirac equation in (2+1) dimensional noncommutative phase
space. We observe that lowest Landau levels are exactly same as in commutative
space and independent of non-commutative parameter. All the Landau levels
become independent of noncommutative parameter for a critical value of the
magnetic field. Several other interesting features along with the relevance of
such models in the study of atomic transitions in a radiation field have been
discussed.Comment: 10 pages, Np figs, communicated to journal. arXiv admin note: text
overlap with arXiv:0907.454
An environmentally benign antimicrobial nanoparticle based on a silver-infused lignin core
Silver nanoparticles have antibacterial properties, but their use has been a cause for concern because they persist in the environment. Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and, together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies have shown that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles
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