Ytterbium-doped tantalum pentoxide waveguides: spectroscopy for compact waveguide lasers

Ytterbium-doped materials are common gain media in high-performance laser systems. In this work, the first spectroscopic investigation of ytterbium-doped tantalum pentoxide (Yb:Ta2O5) for compact waveguide laser applications is presented

Minimizing the Total Cost in the Out Patient Department (OPD) of a Multispecialty Hospital

Waiting lines are experienced in out daily activities. Waiting in line or queue causes inconvenience to individuals (Patients) and economic costs to firms and organizations. Providing too much service capacity to operate a system involves excessive cost. But not providing enough service capacity results in excessive waiting time and cost. In this study the queuing characteristics at the specialist clinic was analysed using a multiserver queuing model and the waiting and service costs determined with a view to determining the optimal service level. This model can also be used by decision and other policy makers to solve other multi-server queuing problems.nbs

An Approach of Initiating Geriatric Screening OPD at the Rural Health Training Centre of SMVMCH, Pondicherry

Objectives: To study the common chronic health problems among the elderly patients attending in recently initiated geriatric screening OPD at the RHTC. Material and Methods: Since one year, screening OPD has been started at RHTC of SMVMCH, for old patients (>60 years), twice a week. A team of trained medical interns, a post-graduate, a faculty in Community Medicine and a counselor screen and counsel the elderly patients for common medical and mental health problems. The screening tool is structured and has been adopted for patients of geriatric OPD at RHTC. The screening tool consist of General Health Questionnaire (GHQ-5), Psychosis screening, Alzheimer’s disease (AD8) questionnaire and checklist of common medical conditions. Patients were screened for early detection of health problems followed by counseling them/their caregivers and referral to specialty OPD for further care. Results: Total 512 elderly patients were screened over 4 months period from the start of geriatric OPD. Out of them, 276 (54%) and 117 (23%) were between the age group of 60-65 years and 66-70 years respectively. Among them 387 (75%) were below poverty line and 68 (13.3%) were having some kind of health insurance. GHQ score indicates that 255 (50%) patients had a score more than one and it was significantly higher among females compared to males. About 76 (16.8%) elderly had a score of > 1 for psychosis, out of which only 12 (14%) were referred to the higher centre. AD8 score shows 204 (40%) patients attended the clinic having a score more than 1 and it is significantly higher among females compared to males. Counseling for caregivers was given only in 13 (6%) of the patients with high AD8 score. Common chronic conditions present among them were joint pains (310, 60%), visual disturbances (247, 48%), hearing difficulty (120, 23.4%) and hypertension (107, 21%). Conclusion: The proportion of people with AD8 score more than 1 is high and most common chronic condition seen is joint pain. The action component of the clinic such as referral of dementia patients, psychosis patients and counseling of their care-givers need to be strengthened

Entanglement entropy in lattice gauge theories

We report on the recent progress in theoretical and numerical studies of entanglement entropy in lattice gauge theories. It is shown that the concept of quantum entanglement between gauge fields in two complementary regions of space can only be introduced if the Hilbert space of physical states is extended in a certain way. In the extended Hilbert space, the entanglement entropy can be partially interpreted as the classical Shannon entropy of the flux of the gauge fields through the boundary between the two regions. Such an extension leads to a reduction procedure which can be easily implemented in lattice simulations by constructing lattices with special topology. This enables us to measure the entanglement entropy in lattice Monte-Carlo simulations. On the simplest example of Z2 lattice gauge theory in (2 + 1) dimensions we demonstrate the relation between entanglement entropy and the classical entropy of the field flux. For SU(2) lattice gauge theory in four dimensions, we find a signature of non-analytic dependence of the entanglement entropy on the size of the region. We also comment on the holographic interpretation of the entanglement entropy.Comment: Talk presented at the Confinement8 conference (Mainz, Germany, September 1 - 6, 2008) and at the conference "Liouville Field Theory and Statistical Models", dedicated to Alexey Zamolodchikov memory (Moscow, Russia, June 21 - 24, 2008

Enhancement of bulk second-harmonic generation from silicon nitride films by material composition

We present a comprehensive tensorial characterization of second-harmonic generation from silicon nitride films with varying composition. The samples were fabricated using plasma-enhanced chemical vapor deposition, and the material composition was varied by the reactive gas mixture in the process. We found a six-fold enhancement between the lowest and highest second-order susceptibility, with the highest value of approximately 5 pm/V from the most silicon-rich sample. Moreover, the optical losses were found to be sufficiently small (below 6 dB/cm) for applications. The tensorial results show that all samples retain in-plane isotropy independent of silicon content, highlighting the controllability of the fabrication process.Comment: 4 pages, 3 figures, 2 tables; Re-submitted to Optics Letter

Fabrication of green nanoinsecticides from agri-waste of corn silk and its larvicidal and antibiofilm properties

he corn silk (CS) is composed of the thread- like stigmas of female inflorescences of Zea mays L. and represents an important waste material from maize crop production that can be recycled in further applications. In this research, the CS was used for the bio-fabrication of Ag nanoparticles (AgNPs) that were evaluated against (I–V) larval instars and pupae of the mosquito vector Aedes aegypti. CS-AgNPs were characterized by UV-Vis spectroscopy, TEM, EDAX, XRD, FTIR, DLS, and zeta potential analysis. Z. mays extract analyzed by gas chro- matography mass spectrometry reveals 14 compounds. The larvicidal effectiveness of CS-fabricated AgNPs was 2.35 μg·mL−1 (I Instar) to 6.24 μg·mL−1 (pupae). The field application in water storage reservoirs of both CS extracts and CS-AgNPs (10 × LC50) led to a 68–69% reduction in larval density after 72 h post-treatment. Ecotoxicological impact of CS-fabricated AgNPs was evaluated on the pre- datory efficacy of Poecilia reticulata on all the larval instars and pupae of Ae. aegypti. Finally, CS-AgNPs were tested to elucidate its anti-biofilm attributes. The CS-AgNPs at 125 μg·mL−1 showed a biofilm inhibition of 90% on S. aureus and 79% on S. epidermidis. These results support the use of CS-AgNPs for futuristic green alternative to mosquito vector management

Length–weight relationship of the endemic velvet leatherjacket, Lalmohania velutina (Hutchins, 1994) inhabiting Gulf of Mannar waters (southeast coast of India)

1097-1098Length–weight relationship (LWR) of an endemic fish, velvet leatherjacket, Lalmohania velutina (Hutchins, 1994) inhabiting Gulf of Mannar (GoM), southeast coast of India was determined during the present study. A total of 131 individuals (male n = 84; females n = 47) were collected from bycatch of shore seines in GoM and used for establishing LWR of this endemic species. The calculated value for parameter 'b' of LWRs were 2.5189, 2.6174 and 2.5614 for male, female and for total individuals (pooled), respectively. Maximum total length (TL) recorded for a female individual (TLmax = 13.4 cm) is the new report of maximum TL in L. velutina. The present study is the first reference on the length-weight relationship and the new maximum length recorded for L. velutina

Heavy Metal Accumulation in Molluscs and sediment from Uppanar Estuary, Southeast Coast of India

The concentration of (Cd, Co, Cu, Fe, Mg, Mn, Pb, Zn) were analyzed in sediments, shells and tissues of the molluscs Meretrix meretrix, Crassostrea madrasensis and Cerithidea cingulata from two stations of Uppanar Estuary, southeast coast of India. The concentrations of the heavy metals analyzed exhibited variations in sediments, tissues and shells of the study animal from all the two stations. Zn and Cu concentration were below the alarming level. In the present study Mg content was found to be higher in shell and tissue. The Fe content was found to be higher in sediment in both the stations, but it was the second highest metal recorded in shell and tissue. Cd and Co was minimum accumulated of all the metals estimated in sediment and animal whereas Mg was recorded maximum (548.3 ± 5) in C. cingulata shell. All the metals analysed were within the safety level. The combined correlation of both the stations between the sediment vs. sediment, tissue vs. tissue, shell vs. shell were positively correlated and significant at P < 0.001 and P < 0.05 level. In addition to continuous contribution of pollutants due to human activities, industries may have a significant contribution of these metals in all the stations. As suggested by many reported studies found in the literature, regular biomonitoring of heavy metal concentrations at these sites is needed since Meretrix meretrix, Crassostrea madrasensis are a popular commercial bivalve in India