Dielectric breakdown in spin polarized Mott insulator

Nonlinear response of a Mott insulator to external electric field, corresponding to dielectric breakdown phenomenon, is studied within of a one-dimensional half-filled Hubbard model. It is shown that in the limit of nearly spin polarized insulator the decay rate of the ground state into excited holon-doublon pairs can be evaluated numerically as well to high accuracy analytically. Results show that the threshold field depends on the charge gap as $F_{th} \propto \Delta^{3/2}$. Numerical results on small systems indicate on the persistence of a similar mechanism for the breakdown for decreasing magnetization down to unpolarised system.Comment: 4 pages, 6 figure

Interaction corrections at intermediate temperatures: dephasing time

We calculate the temperature dependence of the weak localization correction in a two dimensional system at arbitrary relation between temperature, $T$ and the elastic mean free time. We describe the crossover in the dephasing time ${\tau_\phi(T)}$ between the high temperature, $1/\tau_\phi \simeq T^2 \ln T$, and the low temperature $1/\tau_\phi \simeq T$ behaviors. The prefactors in these dependences are not universal, but are determined by the Fermi liquid constant characterising the spin exchange interaction.Comment: 4 pages, to appear in PRB, minor errors corrected, added reference

A study on dog bite incidence in Union Territory of Dadra & Nagar Haveli, India

The injuries caused by dog bites have grown to such epidemic proportions that they are now considered a major public health concern. The epidemiology of dog bites in the UT of Dadra & Nagar Haveli has been evaluated, for the year 2012. This assessment included victims age, sex, biting site and season of the year. During the study, a total of 938 dog bites, were reported from aforesaid place. Of all the dog bites reported, 39.6% victim belonged to age group upto 0-15 year (children) and 60.4% were more than 15 years old (adults). The majority of the incidents 40.8% occurred during the pre monsoon period (1-20 weeks). There was no case of rabies. There is a need to educate the public about the magnitude of dog-bite problems, enforce leash laws and impound stray dogs as an integral part of prevention programs

On the unusual landing of juvenile black pomfret at Veraval and Mangrol landing centre of Gujrat

Pomfrets form an Important component in the fishery off Mangrol and Veraval. They are landed by trawl nets and monofilament gill nets. The silver pomfret Pampas argenteus Is locally called "Vichhuda" and the black pomfret, Formio niger is called "Halva". The former dominates the pomfret fishery with peak landings in the monsoon and post monsoon period. The black pomfret does not show any regular pattern of landing

Record size of Oriental sole (Euryglossa orientalis) (Bloch & Schneider, 1801), caught off Nawabunder, Gujarat

E. orientalis largest ever recorded oriental sole landed in Nawabunder Fishing Harbour in Gujarat caught by Dol net

In-plane Magnetoconductivity of Si-MOSFET's: A Quantitative Comparison between Theory and Experiment

For densities above $n=1.6 \times 10^{11}$ cm$^{-2}$ in the strongly interacting system of electrons in two-dimensional silicon inversion layers, excellent agreement between experiment and the theory of Zala, Narozhny and Aleiner is obtained for the response of the conductivity to a magnetic field applied parallel to the plane of the electrons. However, the Fermi liquid parameter $F_0^\sigma(n)$ and the valley splitting $\Delta_V(n)$ obtained from fits to the magnetoconductivity, although providing qualitatively correct behavior (including sign), do not yield quantitative agreement with the temperature dependence of the conductivity in zero magnetic field. Our results suggest the existence of additional scattering processes not included in the theory in its present form

Electron-electron interaction at decreasing kFlk_Fl

The contribution of the electron-electron interaction to conductivity is analyzed step by step in gated GaAs/InGaAs/GaAs heterostructures with different starting disorder. We demonstrate that the diffusion theory works down to $k_F l\simeq 1.5-2$, where $k_F$ is the Fermi quasimomentum, $l$ is the mean free paths. It is shown that the e-e interaction gives smaller contribution to the conductivity than the interference independent of the starting disorder and its role rapidly decreases with $k_Fl$ decrease.Comment: 5 pages, 6 figure

Bumper landings of Arius dussumieri at Nawabundar.

Marine catfish production showed a continuously declining trend all along the Indian coast, heavy landings of A. dussumieri has been recorded at Nawabundar landing centre. Black tip sea catfish locally known as "Khaga" forms an important seasonal fishery in the Dol nets operated at Nawabundar, contributing 5 to 16% of total fish catch with the annual Estimated catch (tonnes) & Effort of A. dussumieri landed at Nawabundar

Pantoea: A Versatile bacterial Candidate of Agricultural Importance

Genus Pantoea is a diverse group of the family Enterobacteriaceae which inhabit various ecological niches. Various species of Pantoea are found associated with a diverse host range that include plants, animals, insects and humans. Besides this Pantoea spp. has been widely distributed in nature including water, soil, dairy products, meat and fish. It is commonly associated with plants as epiphyte or pathogen. Pantoea was first recognized as a genus about 25 years ago, but since then, approximately 20 species with a wide range of characteristics have been discovered. Identification of plant-pathogenic Pantoea species is difficult, due to the high degree of phenotypic similarity between species of this genus and related Enterobacteriaceae. Pantoea species are typically characterized based on colony morphology, physiological and biochemical tests, and in some cases, fatty acid analysis or quinone composition. These have a wide range of plant hosts where they live as nonpathogenic endophytes as well as epiphytes that colonize the leaves, stems and roots. In this perspective, some Pantoea strains can be beneficial to the plant host by providing growth promoting substances such as the plant-growth hormone indole-acetic acid (IAA), phosphate solubilization or nitrogen fixation. Number of Pantoea species are also involved in bioremediation of various pesticides and organic chemical compounds. This indicates the potential to degrade some recalcitrant and xenobiotic compounds. Some Pantoea strains also provide effective protection to plants against various bacterial and fungal diseases and post-harvest fruit rots. On the other hand, some of the species are recognized as a human pathogen and has led to controversy as limited documented cases of P. agglomerans bacteremia and infections have been reported. Most of the cases reported among immunocompromised patients or the pediatric population. Thus, Pantoea is a multifaceted bacterium that plays a significant role in agriculture as a plant growth promoter by producing hormone like IAA, inorganic pollutant degradation by producing potent enzymes and also protects some plants against pathogens by producing antibacterial and antifungal compounds. In some cases, these also cause diseases in human beings. Therefore, this genus is very important for studies. In this review, the industrial, agricultural as well as ecological significance of the genus Pantoea is emphasized

Sudden emergence of fishery and some aspects of biology and population dynamics of Aluterus monoceros (Linnaeus, 1758) at Veraval

The sudden emergence of a fishery and selected aspects of biology and population dynamics of Aluterus monoceros landed by trawlers at Veraval was studied from January 2008 to December 2009. Total catch of 475 t recorded in September 2009, which increased to 7042 t in October dominated in the trawl landings with a contribution of 29.5%. However, in November and December, the catch decreased sharply to 1374 t and 94 t, respectively. The combined length-weight relationship was log W = -1.50 + 2.694 log L (r = 0.86) (n = 222) indicating allometric growth. Sex ratio was 1:1.05 (n = 129). Females attained sexual maturity at 50.2 cm total length. Zoobenthos, dominated by benthic invertebrates, cnidarians and worms, zooplankton dominated by copepods and nekton dominated by Acetes spp. and clupeid juveniles were the major food items of A. monoceros. The von Bertalanffy growth equation was Lt = 63.53 [1 – e - 0.22 (t + 0.077)]. Natural mortality, fishing mortality and exploitation ratio were 0.53, 0.58 and 0.52 respectivel