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

Dynamics of Priacanthus hamrur (Forsskal) exploited off Saurashtra coast

Bull’s eye landings off Saurashtra reached a peak of 3813 tons in 1999 with a catch rate of 4.3 kg per haul. The group is represented by a single species, Priacanthus hamrur (Forsskal). Gut content analysis revealed P. hamrur to be a carnivorous fish with a preference for pelagic crustaceans and fishes. Spawning females were encountered from March to December and the length at first maturity of female P. hamrur was 198 mm. Recruitment to the fishery takes place with two peaks annually - one in January-February and a minor one in October-November. A common length-weight relationship for both sexes was obtained with a = 3.481x105 and b = 2.83498. The von Bertalanffy growth equation was derived as Lt = 360.35 [1-e-0.56(t+ 0.1013)] and the length attained by the fish at the end of 1 to 4 years were estimated as 165, 249, 296 and 324 mm. The length growth performance index was obtained as !’ = 4.86 and the longevity, tmax was estimated as 4.44 years. The mortality co-efficient Z, M and F were 2.35, 1.14 and 1.21, respectively and exploitation rate, E was 0.51. Stock assessment studies reveal that the present average annual catch can be increased by 764 t to reach the MSY of 4996 tons

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

Record landings of cephalopods by trawlers at Veraval during first quarter of 2009

Cephalopods represent one of the most important exploited marine fishery resources at Veraval. The cephalopod landings in Gujarat increased by more than two folds from 0.234 lakh t in 2002 to 0.49 lakh t in 2006 (Mohanraj et al., 2009), with a concomitant increase in catch rate from 5.05 kg h-1 in 2003 to 14.74 kg h-1 in 2006. The cephalopod resource was constituted mainly by Loligo duvauceli, Sepia pharaonis and S. aculeat

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

Fetomaternal outcome in breech delivery

Background: Breech Presentation is the commonest of all malpresentations. Vaginal delivery of the breech presentations at term is associated with a much higher perinatal mortality and morbidity than that of vertex presentation. The objectives of the present study are to know the common causes leading to breech presentation. Further, to compare the different management protocols and outcome in different types of breech presentation.  Also, to know the perinatal morbidity and mortality associated with different types of breech presentation nd comparison of perinatal morbidity and mortality with vaginal delivery against cesarean section.Methods: This is a retrospective study of randomized 100 cases of pregnant women in labour with breech presentations after 28 weeks or more attending C U Shah Medical College, Surendranagar, over a period of May 2012 to April 2014.Results: Out of 100 patients breech presentation was more common in booked patients and multigravida. In primi and multigravidae patients, caesarean delivery was more compared to assisted breech delivery. Perinatal outcome was good in majority of the patients in both extended and complete breech with an incidence of 94% and 88% respectively. perinatal outcome was good in caesarean section with 100% compared to assisted breech delivery 93%.Conclusions: The balanced decision about the mode of delivery on a case by case basis as well as conduct, training and regular drills of assisted breech delivery will go a long way to optimize the outcome of breech presentation like ours. Delivery of breech fetus when labor and delivery is supervised and or conducted by experienced obstetrician lowers maternal morbidity, neonatal morbidity and mortality

Water users' association in Bhima Lift Irrigation Scheme: Farmers' experience

Water users' associationsCooperativesWater distributionLow lift irrigationIrrigation canalsWater ratesCropping systems

By-catch of the gastropod Tibia spp. in gillnets operated along Gujarat coast

The rocky coastal belt of Gujarat possesses an enormous potential resource of lobsters. Gillnets are regularly operated for lobster along the coast of Mangrol, Porbunder and Muldwarka. Gastropods such as Tibia maculata and Tibia curta occurred in large quantities as by-catch along with lobsters. Other gastropods such as Archipecten sp. and Murex sp. also make their occurrence in small quantities