1,598 research outputs found

    Range extension of a mantis Shrimp <em>Harpiosquilla harpax</em> (Family: Squillidae) in the Chilika Lagoon

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    18-24The present study describes the first live occurrence of a species of mantis shrimp i.e. Harpiosquilla harpax from the Chilika lagoon. It was a new record to Chilika after the opening of natural inlet due to super cyclone Phailin during October 2013 and range extension from Visakhapatnam coast.  However, concrete information regarding its population and spatio-temporal distribution is certainly not known. since it was caught as by catch. Food and feeding behaviour and morphological structure of the compound eye and ommatidia was also studied

    A simple sum rule for the thermal gluon spectral function and applications

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    In this paper, we derive a simple sum rule satisfied by the gluon spectral function at finite temperature. This sum rule is useful in order to calculate exactly some integrals that appear frequently in the photon or dilepton production rate by a quark gluon plasma. Using this sum rule, we rederive simply some known results and obtain some new results that would be extremely difficult to justify otherwise. In particular, we derive an exact expression for the collision integral that appears in the calculation of the Landau-Pomeranchuk-Migdal effect.Comment: 24 latex pages, 2 postscript figure

    Enhanced thermal production of hard dileptons by 323\to 2 processes

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    In the framework of the Hard Thermal Loop effective theory, we calculate the two-loop contributions to hard lepton pair production in a quark-gluon plasma. We show that the result is free of any infrared and collinear singularity. We also recover the known fact that perturbation theory leads to integrable singularities at the location of the threshold for qqˉγq\bar{q}\to\gamma^*. It appears that the process calculated here significantly enhances the rate of low mass hard dileptons.Comment: 32 latex pages, 14 postscript figure

    Impact of torrential rain on coastal ecosystem at kalpakkam, southeast coast of India

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    1609-1615The present study focuses on the drastic changes observed in the coastal ecosystem at Kalpakkam during flooding event due to huge rainfall that occurred in and around northern Tamil Nadu during December 2015. A significant increase in hydrological parameters (nitrate, phosphate, silicate, total nitrogen and phosphorous) was recorded as compared to previous years (2006-2014). In the present instance, the coastal water salinity which was about 19 psu was the lowest as compared to the data available since 1979. The phytoplankton population density was severely affected by the runoff. The present observed density 1.4 x 104 cells l-1 was the lowest among the available data at this coast. Availability of green algae species in the coastal waters was significantly high (10 species, 17 % of total species) as compared to previous reports. One of the most interesting features of this study was the observation of epibiosis on zooplankton in massive numbers. A comparison of previous occurrences of epibiotic relationship in plankton community with the present observation showed a staggering increase in epibiosis to 38 % of zooplankton species as compared to 5-13 % during 2008-2014

    Nearly perfect fluid in Au+Au collisions at RHIC

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    In the Israel-Stewart's theory of dissipative hydrodynamics, we have analysed the STAR data on ϕ\phi meson production in Au+Au collisions at s\sqrt{s}=200 GeV. From a simultaneous fit to ϕ\phi mesons multiplicity, mean pTp_T and integrated v2v_2, we obtain a phenomenological estimate of QGP viscosity, η/s=0.07±0.03±0.14\eta/s =0.07 \pm 0.03 \pm 0.14, the first error is due to the experimental uncertainty in STAR measurements, the second reflects the uncertainties in initial and final conditions of the fluid.Comment: 5 pages, 6 figures. Version accepted for publication in Phys. Lett.

    Effect Of Pre-freeze Addition Of Cysteine Hydrochloride And Reduced Glutathione On Post-thaw Sperm Parameters And Field Fertility In Jersey Crossbred Bull Semen

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    The present study was aimed to assess the effect of pre-freeze addition of cysteine hydrochloride and glutathione (GSH) on post-thaw sperm functional parameters and field fertility. The experimental bulls aged 4 to 6 years were used for the present study. A total of 36 ejaculates, 6 ejaculates from each bull (n=6) were collected and divided in to three groups, group I (control), group II (5mM cysteine hydrochloride) and group III (5mM GSH). The extended semen samples were added with @5mM additives, filled in mini straw using automatic filling and sealing machine (IMV, France) and cryopreserved in liquid nitrogen. Post-freeze seminal traits were also recorded after thawing at 37oC for 30 seconds. Post thaw livability was significantly (p&#x3c; 0.01) higher in GSH group as compared to cysteine and control groups. The loss of acrosomal integrity was significantly (p&#x3c; 0.01) lower in GSH group than cysteine and control groups. Analysis of variance for post thaw motility parameters (Forward progressive and Total motility) has revealed that significant difference (p&#x3c; 0.05) between the good and poor freezer in the group II and there was no difference in the group I and III under study at 0 and 1 hr incubation period and at 2 hrs the group III and at 4 hrs group I has revealed significance difference (p&#x3c; 0.05).The curvilinear velocity (VCL) and amplitude of lateral head displacement (ALH) values were significantly (P&#x3c;0.05) higher in GSH than the cysteine and control groups. The Mitochondrial membrane potential (per cent) had no significance difference between the treatment groups. The present study indicates that the addition of cysteine and GSH suggestive of reducing lipid peroxide levels. The conception rate (%) in glutathione (68) added semen was significantly (p&#x3e;0.05) higher than cysteine (58) and control (49) groups. The post-thaw sperm progressive forward motility (r=0.4) had moderate but, no significant correlation with conception rate. However post-thaw VSL (r=0.7), loss of acrosomal integrity (r=-0.8) and mitochondrial membrane potential (r=0.9) had significant (p&#x3c; 0.05) correlation with field fertility. The present study indicates that the use of glutathione as semen additives may be recommended for improving semen quality and overall augmentation of pregnancy in cows. The present study suggests that pre-freeze addition of glutathione was found to be better than cysteine in improving sperm fertility

    Monitoring, Corporate Performance and Institutional Directors

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    This is the pre-peer reviewed version of the following article: Monitoring, Corporate Performance and Institutional Directors, which has been published in final form at https://doi.org/10.1111/auar.12262. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Our main objective is to study the effect of institutional directors on firm performance, distinguishing directors according to whether they maintain business relationships (pressure‐sensitive) or not (pressure‐resistant). Our results show that in weak regulatory and low investor protection environments, institutional directors have a negative impact on corporate performance. Our evidence shows that this negative effect is mainly driven by the role of pressure‐resistant directors and not for those directors representing mainly banks and other financial institutions with a long‐term investment horizon. These findings have implications for numerous parties, such as institutional investors, regulators, potential new board members and other corporate governance reform proponents, who frequently examine board characteristics to assess the effectiveness of boards in value‐creation policies

    Optical Activity From Extra Dimension

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    Optical activity, like Faraday effect, is a rotation of the plane of polarization of propagating light in a medium and can be attributed to different sources with distinct signatures. In this note we discuss the effect of optical activity {\it{in vacuum}} due to Kaluza-Klein scalar field ϕ\phi, in the presence of an external electro-magnetic field. The astrophysical implication of this effect is indicated. We also point out the possibility of observing the same in laboratory conditions.Comment: Four Page

    A Honeycomb Proportional Counter for Photon Multiplicity Measurement in the ALICE Experiment

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    A honeycomb detector consisting of a matrix of 96 closely packed hexagonal cells, each working as a proportional counter with a wire readout, was fabricated and tested at the CERN PS. The cell depth and the radial dimensions of the cell were small, in the range of 5-10 mm. The appropriate cell design was arrived at using GARFIELD simulations. Two geometries are described illustrating the effect of field shaping. The charged particle detection efficiency and the preshower characteristics have been studied using pion and electron beams. Average charged particle detection efficiency was found to be 98%, which is almost uniform within the cell volume and also within the array. The preshower data show that the transverse size of the shower is in close agreement with the results of simulations for a range of energies and converter thicknesses.Comment: To be published in NIM
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