Delocalization of slowly damped eigenmodes on Anosov manifolds

We look at the properties of high frequency eigenmodes for the damped wave equation on a compact manifold with an Anosov geodesic flow. We study eigenmodes with spectral parameters which are asymptotically close enough to the real axis. We prove that such modes cannot be completely localized on subsets satisfying a condition of negative topological pressure. As an application, one can deduce the existence of a "strip" of logarithmic size without eigenvalues below the real axis under this dynamical assumption on the set of undamped trajectories.Comment: 28 pages; compared with version 1, minor modifications, add two reference

Extended metal-organic solids based on benzenepolycarboxylic and aminobenzoic acids

This article describes the recent results obtained in our laboratory on the interaction of polyfunctional ligands with divalent alkaline earth metal ions and a few divalent transition metal ions. Treatment of MC12·nH2O (M = Mg, Ca, Sr or Ba) with 2-amino benzoic acid leads to the formation of complexes [Mg(2-aba)2] (1), [Ca(2-aba)2(OH2)3]∞ (2), [{Sr(2-aba)2(OH2)2}2·H2O)]∞ (3), [Ba(2-aba)2(OH2)]∞ (4), respectively. While the calcium ions in 2 are hepta-coordinated, the strontium and barium ions in 3 and 4 reveal a coordination number of nine apart from additional metal-metal interactions. Apart from the carboxylate functionality, the amino group also binds to the metal centres in the case of strontium and barium complexes 3 and 4. Complexes [{Mg(H2O)6}(4-aba)2·2H2O] (5), [Ca(4-aba)2(H2O)2] (6) prepared from 4-aminobenzoic acid reveal more open or layered structures. Interaction of 2-mercaptobenzoic acid with MCl2·6H2O (M = Mg, Ca), however, leads to the oxidation of the thiol group resulting in the disulphide 2,2' -dithiobis(benzoic acid). New metal-organic framework based hydrogen-bonded porous solids [{M(btec) (OH2)4}n·n(C4H12N2)·4nH2O] (btec = 1,2,4,5-benzene tetracarboxylate) (M = Co9; Ni10; Zn11) have been synthesized from 1,2,4,5-benzene tetracarboxylic acid in the presence of piperazine. These compounds are made up of extensively hydrogen-bonded alternating layers of anionic M-btec co-ordination polymer and piperazinium cations. Compounds 2- 11 described herein form polymeric networks in the solid-state with the aid of different coordinating capabilities of the carboxylate anions hydrogen bonding interactions

Benign breast diseases: experience at a teaching hospital in rural India

Background: Though benign breast diseases are very common with nearly 1/3 of women suffering some time during their life time, not many studies have focused on this entity, especially in rural areas. Our teaching hospital situated amongst the villages in rural part of India provided the right background for the study.  Objective: To determine the frequency of benign breast diseases in a teaching hospital situated in the rural setting and to analyze the role of triple assessment in assessing benign breast diseases.Study design: Prospective, descriptive study.Setting: MVJ Medical College and Research Hospital, Hoskote, Bangalore Rural district, Karnataka, India.Method of study: Data including age, complaints, clinical examination, radiological investigations and histopathological diagnosis was collected from patients presenting to the department of surgery with breast complaints. Patients with carcinoma of the breast were excluded from the study.Results: A total of 110 patients were studied between November 2009 to March 2011. Mean age of patients was 28.6 years. Fibroadenoma was the most common diagnosis in 56.4% followed by fibroadenosis in 20.9%. There was one case each of lipoma, tuberculosis and duct ectasia and two cases of atypical ductal hyperplasia. The sensitivity of clinical diagnosis in our study was 91.1% and FNAC was 100% accurate in all patients with fibroadenoma but had a sensitivity of only 78% in the diagnosis of fibroadenosis. Only 3.3% of cases of fibroadenoma were treated conservatively

Mineral Composition of Marine Macroalgae from Mandapam Coastal Regions; Southeast Coast of India

The present study focused on the trace metal and mineral composition analysis of various seaweeds such as Chlorophyceae (Cladophora glomerata, Ulva reticulata, Halimeda macroloba, H.tuna), Phaeophyceae (Dictyota dichotoma, Padina pavonica) Rhodophyceae (Gracilaria crassa, Gelidiella acerosa, Hypnea musciformis) collected from Mandapam coastal regions, Southeast coast of India. Among these groups of seaweeds, U. reticulata belonging to the Chlorophyceae showed the maximum contents of mineral elements such as chromium, copper, and magnesium. H.tuna observed the minimum level of mineral content such as cobalt, iron, magnesium, manganese, nickel, lead and zinc

YAPA: A generic tool for computing intruder knowledge

Reasoning about the knowledge of an attacker is a necessary step in many formal analyses of security protocols. In the framework of the applied pi calculus, as in similar languages based on equational logics, knowledge is typically expressed by two relations: deducibility and static equivalence. Several decision procedures have been proposed for these relations under a variety of equational theories. However, each theory has its particular algorithm, and none has been implemented so far. We provide a generic procedure for deducibility and static equivalence that takes as input any convergent rewrite system. We show that our algorithm covers most of the existing decision procedures for convergent theories. We also provide an efficient implementation, and compare it briefly with the tools ProVerif and KiSs

Semiclassical measures and the Schroedinger flow on Riemannian manifolds

In this article we study limits of Wigner distributions (the so-called semiclassical measures) corresponding to sequences of solutions to the semiclassical Schroedinger equation at times scales $\alpha_{h}$ tending to infinity as the semiclassical parameter $h$ tends to zero (when $\alpha _{h}=1/h$ this is equivalent to consider solutions to the non-semiclassical Schreodinger equation). Some general results are presented, among which a weak version of Egorov's theorem that holds in this setting. A complete characterization is given for the Euclidean space and Zoll manifolds (that is, manifolds with periodic geodesic flow) via averaging formulae relating the semiclassical measures corresponding to the evolution to those of the initial states. The case of the flat torus is also addressed; it is shown that non-classical behavior may occur when energy concentrates on resonant frequencies. Moreover, we present an example showing that the semiclassical measures associated to a sequence of states no longer determines those of their evolutions. Finally, some results concerning the equation with a potential are presented.Comment: 18 pages; Theorems 1,2 extendend to deal with arbitrary time-scales; references adde

Yeast functional screen to identify genetic determinants capable of conferring abiotic stress tolerance in Jatropha curcas

<p>Abstract</p> <p>Background</p> <p>Environmentally inflicted stresses such as salinity and drought limit the plant productivity both in natural and agricultural system. Increasing emphasis has been directed to molecular breeding strategies to enhance the intrinsic ability of plant to survive stress conditions. Functional screens in microorganisms with heterologous genes are a rapid, effective and powerful tool to identify stress tolerant genes in plants. <it>Jatropha curcas </it>(Physic nut) has been identified as a potential source of biodiesel plant. In order to improve its productivity under stress conditions to benefit commercial plantations, we initiated prospecting of novel genes expressed during stress in <it>J. curcas </it>that can be utilized to enhance stress tolerance ability of plant.</p> <p>Results</p> <p>To identify genes expressed during salt tolerance, cDNA expression libraries were constructed from salt-stressed roots of <it>J. curcas</it>, regulated under the control of the yeast <it>GAL1 </it>system. Using a replica based screening, twenty thousand yeast transformants were screened to identify transformants expressing heterologous gene sequences from <it>J. curcas </it>with enhanced ability to tolerate stress. From the screen we obtained 32 full length genes from <it>J. curcas </it>[GenBank accession numbers <ext-link ext-link-id="FJ489601" ext-link-type="gen">FJ489601</ext-link>-<ext-link ext-link-id="FJ489611" ext-link-type="gen">FJ489611</ext-link>, <ext-link ext-link-id="FJ619041" ext-link-type="gen">FJ619041</ext-link>-<ext-link ext-link-id="FJ619057" ext-link-type="gen">FJ619057</ext-link> and <ext-link ext-link-id="FJ623457" ext-link-type="gen">FJ623457</ext-link>-<ext-link ext-link-id="FJ623460" ext-link-type="gen">FJ623460</ext-link>] that can confer abiotic stress tolerance. As a part of this screen, we optimized conditions for salt stress in <it>J. curcas</it>, defined parameters for salt stress in yeast, as well as isolated three salt hypersensitive yeast strains <it>shs-2, shs-6 </it>and <it>shs-8 </it>generated through a process of random mutagenesis, and exhibited growth retardation beyond 750 mM NaCl. Further, we demonstrated complementation of the salt sensitive phenotypes in the <it>shs </it>mutants, and analyzed the expression patterns for selected <it>J. curcas </it>genes obtained from the screen in both leaf and root tissues after salt stress treatments.</p> <p>Conclusions</p> <p>The approach described in this report provides a rapid and universal assay system for large scale screening of genes for varied abiotic stress tolerance within a short span of time. Using this screening strategy we could isolate both genes with previously known function in stress tolerance as well as novel sequences with yet unknown function in salt stress tolerance from <it>J. curcas</it>. The isolated genes could be over-expressed using plant expression system to generate and evaluate transgenic plants for stress tolerance as well as be used as markers for breeding salt stress tolerance in plants.</p

Monitoring of Noctiluca Bloom in Mandapam and Keelakarai Coastal Waters; Southeast Coast of India

Monitoring the Harmful Algal Blooms was carried out during July to December 2008 in Mandapam and Keelakarai coastal waters of Tamil Nadu, Southeast coast of India. In the month of October several fishes and shellfishes were died due to Noctiluca blooms along these two areas. The present investigation the following species of phyto and zooplankton were found to be common; phytoplankton such as Coscinodiscus sp., Skeletonema costatum, Bacillaria paradoxa, Thallassiothrix frauenfeldii, T. longisima, Leptocylindrus sp., and  zooplankton such as Paracalanus parvus, Acrocalanus gracilis, Pseudodiaptomus serricautatus, Rhincalanus cornutus, R. nasutus, Euterpina acutifrons, Nannocalanus minor, Eucalanus attenuates, E. crassus, Fish larvae, Fish eggs, Barnacle nauplii, Bivalve larvae, Gastropod larvae, Copepod nauplii  and Mysis larvae. The hydrobiological parameters also analysed during bloom and after blooms; the dissolved oxygen (2.6 – 4.9µM L-1) nutrients varied between nitrate (0.66 – 1.01µM L-1) nitrite (0.11 – 0.21µM L-1) phosphate (0.51 – 0.86µM L-1) and silicate (0.81 – 4.2µM L-1)

Entropic bounds on semiclassical measures for quantized one-dimensional maps

Quantum ergodicity asserts that almost all infinite sequences of eigenstates of a quantized ergodic system are equidistributed in the phase space. On the other hand, there are might exist exceptional sequences which converge to different (non-Liouville) classical invariant measures. By the remarkable result of N. Anantharaman and S. Nonnenmacher math-ph/0610019, arXiv:0704.1564 (with H. Koch), for Anosov geodesic flows the metric entropy of any semiclassical measure must be bounded from below. The result seems to be optimal for uniformly expanding systems, but not in general case, where it might become even trivial if the curvature of the Riemannian manifold is strongly non-uniform. It has been conjectured by the same authors, that in fact, a stronger bound (valid in general case) should hold. In the present work we consider such entropic bounds using the model of quantized one-dimensional maps. For a certain class of non-uniformly expanding maps we prove Anantharaman-Nonnenmacher conjecture. Furthermore, for these maps we are able to construct some explicit sequences of eigenstates which saturate the bound. This demonstrates that the conjectured bound is actually optimal in that case.Comment: 38 pages, 4 figure