Non-symmetric trapped surfaces in the Schwarzschild and Vaidya spacetimes

Marginally trapped surfaces (MTSs) are commonly used in numerical relativity to locate black holes. For dynamical black holes, it is not known generally if this procedure is sufficiently reliable. Even for Schwarzschild black holes, Wald and Iyer constructed foliations which come arbitrarily close to the singularity but do not contain any MTSs. In this paper, we review the Wald-Iyer construction, discuss some implications for numerical relativity, and generalize to the well known Vaidya spacetime describing spherically symmetric collapse of null dust. In the Vaidya spacetime, we numerically locate non-spherically symmetric trapped surfaces which extend outside the standard spherically symmetric trapping horizon. This shows that MTSs are common in this spacetime and that the event horizon is the most likely candidate for the boundary of the trapped region.Comment: 4 pages, 3 figures; v2: minor modifications; v3: clarified conclusion

Degradation and breakdown characteristics of thin MgO dielectric layers

MgO has been suggested as a possible high-k dielectric for future complementary metal-oxide semiconductor processes. In this work, the time dependent dielectric breakdown (TDDB) characteristics of 20 nm MgO films are discussed. Stress induced leakage current measurements indicate that the low measured Weibull slopes of the TDDB distributions for both n-type and p-type devices cannot be attributed to a lower trap generation rate than for SiO2. This suggests that much fewer defects are required to trigger breakdown in MgO under voltage stress than is the case for SiO2 or other metal-oxide dielectrics. This in turn explains the progressive nature of the breakdown in these films which is observed both in this work and elsewhere. The reason fewer defects are required is attributed to the morphology of the films

Unusual ocean-atmosphere conditions in the tropical Indian Ocean during 1994

The southeastern tropical Indian Ocean (SETIO) was characterized by unusually cold sea surface temperature (SST) and strong northwestward alongshore surface winds during 1994. Using multi-source data sets including ocean model simulation, two key processes are identified for the SETIO cooling. Entrainment cooling produced most of the negative SST anomaly near the coast whereas evaporative cooling dominated the process away from the coast. Convection was anomalously suppressed over SETIO and the divergence of moist air from the region helped the local evaporative process. This also led to anomalous moisture transports that explain the enhanced convection over the central equatorial Indian Ocean, India and East Asia. The positive feedback between the enhanced and suppressed convection regions in turn helped maintain the surface wind anomalies. These evidences clearly indicate the existence of an ocean-atmosphere coupled phenomenon in the Indian Ocean during 1994

The Development of Iron and Steel Industry in India's Five Year Plans

Many thousands of years separate us from the historic Iron Age when man first learned how to smelt iron from ore and shape it into tools and weapons. Since then, the number of metals and alloys developed by man for his needs has been greatly extended, but still iron and steel hold the uncha-llenged supremacy as can be seen from the fact that during the first quarter of the present century the quantity of iron and steel produced and used throughout the world was much more than that of any other metal. In the recon-struction and economic development of our country.Whether it relates to greater industrial production or increased development of water and power resources, transport and agriculture or development of cottage industries, it is the iron and steel industry that forms the backbone allot provides scope for maximum employment of ever increasing population

Association of DNA damage and dyslipidemia with polycystic ovarian syndrome

Polycystic ovary syndrome (PCOS) is associated with hyperinsuli-nemia and insulin resistance which may lead to cardiovascular diseases. Evidence for cardiovascular events in women who were affected by PCOS during fertile age is limited. The pathogenesis is unknown; however, it is a complex multigenetic disorder. The present study was undertaken to evaluate the various cardiovas-cular risk factors and their DNA repair efficiency in women with PCOS by investigating the biochemical, endocrinological and mo-lecular cytogenetic alterations. These investigations were carried out in 116 women in the age group of 15-35 years clinically diag-nosed with PCOS. Data were compared with that of 50 age-matched healthy normal women. Fasting blood sugar (FBS), Lipid profile, Follicle-Stimulating Hormone (FSH) and Luteinizing Hor-mone (LH), Prolactin and Estradiol were estimated after getting the informed consent. Mutagen induced chromosome sensitivity analysis was carried out in the lymphocytes of the subjects to as-sess the DNA repair proficiency. Fasting Blood Sugar, total cho-lesterol and LDL cholesterol were found to be elevated whereas HDL cholesterol was found to be lowered in the test subjects. FSH, LH and prolactin were also found to be significantly elevated in the test subjects. Change in the estradiol concentration in the test subjects was not significant. The mutagen sensitivity analysis revealed a significant elevation in break per cell (b/c) values indi-cating a deficiency in the DNA repair mechanism / DNA damage in PCOS patients. Modification of life style by changing the dietary habit and sedentary life style will help to reduce the oxidative stress and may increase the ovarian function and a sensible life-style management is recommended for reducing the risk for CVD

P09-15. Selection of higher avidity HLA-restricted T cell responses as a viral adaptation strategy

Loss of immune reactivity due to HIV mutational escape is well described. Data generated from a large population-based study (n>800) suggested that certain CD8 T cell epitopes are created as a result of HIV adaptation and are associated with enhanced viral replication. Here we sought to investigate the HLA-restricted T-cell responses associated with seven such adaptations