Preheating after multifield inflation with nonminimal couplings, II: Resonance Structure

This is the second in a series of papers on preheating in inflationary models comprised of multiple scalar fields coupled nonminimally to gravity. In this paper, we work in the rigid-spacetime approximation and consider field trajectories within the single-field attractor, which is a generic feature of these models. We construct the Floquet charts to find regions of parameter space in which particle production is efficient for both the adiabatic and isocurvature modes, and analyze the resonance structure using analytic and semi-analytic techniques. Particle production in the adiabatic direction is characterized by the existence of an asymptotic scaling solution at large values of the nonminimal couplings, $\xi_I \gg 1$, in which the dominant instability band arises in the long-wavelength limit, for comoving wavenumbers $k \rightarrow 0$. However, the large-$\xi_I$ regime is not reached until $\xi_I \geq {\cal O} (100)$. In the intermediate regime, with $\xi_I \sim {\cal O}(1 - 10)$, the resonance structure depends strongly on wavenumber and couplings. The resonance structure for isocurvature perturbations is distinct and more complicated than its adiabatic counterpart. An intermediate regime, for $\xi_I \sim {\cal O} (1 - 10)$, is again evident. For large values of $\xi_I$, the Floquet chart consists of densely spaced, nearly parallel instability bands, suggesting a very efficient preheating behavior. The increased efficiency arises from features of the nontrivial field-space manifold in the Einstein frame, which itself arises from the fields' nonminimal couplings in the Jordan frame, and has no analogue in models with minimal couplings. Quantitatively, the approach to the large-$\xi_I$ asymptotic solution for isocurvature modes is slower than in the case of the adiabatic modes.Comment: 46 pages, 23 figures. References added and minor edits made to match published versio

Preheating after multifield inflation with nonminimal couplings, III: Dynamical spacetime results

This paper concludes our semi-analytic study of preheating in inflationary models comprised of multiple scalar fields coupled nonminimally to gravity. Using the covariant framework of paper I in this series, we extend the rigid-spacetime results of paper II by considering both the expansion of the universe during preheating, as well as the effect of the coupled metric perturbations on particle production. The adiabatic and isocurvature perturbations are governed by different effective masses that scale differently with the nonminimal couplings and evolve differently in time. The effective mass for the adiabatic modes is dominated by contributions from the coupled metric perturbations immediately after inflation. The metric perturbations contribute an oscillating tachyonic term that enhances an early period of significant particle production for the adiabatic modes, which ceases on a time-scale governed by the nonminimal couplings $\xi_I$. The effective mass of the isocurvature perturbations, on the other hand, is dominated by contributions from the fields' potential and from the curvature of the field-space manifold (in the Einstein frame), the balance between which shifts on a time-scale governed by $\xi_I$. As in papers I and II, we identify distinct behavior depending on whether the nonminimal couplings are small ($\xi_I \lesssim {\cal O} (1)$), intermediate ($\xi_I \sim {\cal O} (1 - 10)$), or large ($\xi_I \geq 100$).Comment: 34 pages, 11 figures. References added and minor edits made to match published versio

A Protease Isolated from the Latex of Plumeria rubra Linn (Apocynaceae) 1: Purification and Characterization

Purpose: To isolate, purify and characterize protease from the latex of the plant.Methods: Protease was isolated from the latex of Plumeria rubra Linn using acetone precipitation method and purified by a sequence of DEAE cellulose column chromatography, followed by two successive column purification in Sephadex G-50 and Sephadex G-200. The molecular weight of the purified protease was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDSPAGE). The protease was given a trivial name, Plumerin-R.Results: Plumerin-R showed a single protein band on SDS-PAGE and molecular weight was approximately 81.85 kDa. It remained active over a broad range of temperature but had optimum activity at 55 °C and pH 7.0 when casein was used as substrate. Activation of the protease by a thiol-activating agent indicated the presence of sulfhydryl as an essential group for its activity.Conclusion: A protease from the latex of Plumeria rubra Linn was purified to homogeneity by a simple purification procedure and then characterized.Keywords: Protease, Plumerin-R, Sulfhydryl, Purification; Characterizatio

A fluorophore attached to nicotinic acetylcholine receptor beta M2 detects productive binding of agonist to the alpha delta site

To study conformational transitions at the muscle nicotinic acetylcholine (ACh) receptor (nAChR), a rhodamine fluorophore was tethered to a Cys side chain introduced at the beta-19' position in the M2 region of the nAChR expressed in Xenopus oocytes. This procedure led to only minor changes in receptor function. During agonist application, fluorescence increased by (Delta-F/F) approximate to 10%, and the emission peak shifted to lower wavelengths, indicating a more hydrophobic environment for the fluorophore. The dose-response relations for Delta-F agreed well with those for epibatidine-induced currents, but were shifted approximate to 100-fold to the left of those for ACh-induced currents. Because (i) epibatidine binds more tightly to the alpha-gamma-binding site than to the alpha-delta site and (ii) ACh binds with reverse-site selectivity, these data suggest that Delta-F monitors an event linked to binding specifically at the alpha-delta-subunit interface. In experiments with flash-applied agonists, the earliest detectable Delta-F occurs within milliseconds, i.e., during activation. At low [ACh] (less than or equal to 10 muM), a phase of Delta-F occurs with the same time constant as desensitization, presumably monitoring an increased population of agonist-bound receptors. However, recovery from Delta-F is complete before the slowest phase of recovery from desensitization (time constant approximate to 250 s), showing that one or more desensitized states have fluorescence like that of the resting channel. That conformational transitions at the alpha-delta-binding site are not tightly coupled to channel activation suggests that sequential rather than fully concerted transitions occur during receptor gating. Thus, time-resolved fluorescence changes provide a powerful probe of nAChR conformational changes

A Protease Isolated from the Latex of Plumeria rubra Linn (Apocynaceae) 2: Anti-inflammatory and Wound- Healing Activities

Purpose: The aim of this study was to investigate the anti-inflammatory and wound-healing activities of the protease isolated from the latex of Plumeria rubra Linn.Methods: The protease was isolated from the latex of the plant by acetone precipitation method and given a trivial name, Plumerin-R. The anti-inflammatory activity of the protease was based on its effects on carrageenan-induced paw oedema in rats. Its wound healing effect was investigated using an excision wound rat model.Results: Four hours after treatment, the reduction in carrageenan-induced rat paw oedema by 20, 40 and 80 mg/kg body weight of plumerin-R was 21.6, 33.8 and 48.8 %, respectively, while oedema reduction by indomethacin (10 mg/kg) was 58.0 %. Plumerin-R showed significant (p < 0.05) wound closure and epithelialization time compared with control.Conclusion: This study demonstrates that the protease, Plumerin-R, has significant anti-inflammatory and wound-healing properties.Keywords: Protease, Plumerin-R, Anti-inflammatory, Excision wound, Healing

A new species of Philautus (Anura: Rhacophoridae) from the Eastern Ghats, south-eastern India

A new species of Philautus is described from the vicinity of Vishakhapatnam, Andhra Pradesh in south-eastern India. The new species is compared with congeners from peninsular India and Sri Lanka. Since the members of the genus are restricted to wet evergreen forests of the region, remnant patches of wet forests within a now largely degraded and arid Eastern Ghats are apparently refugia, supporting species that are tolerant of mesic conditions

Leptobrachium smithi Matsui, Nabitabhata, and Panha, 1999 (Anura: Megophryidae), an Addition to the Fauna of Myanmar (Burma)

Three specimens of Leptobrachium from the collections of the Zoological Survey of India are identified as Leptobrachium smithi. These specimens were collected by Limborg in 1877. These are the first confirmed records of Leptobrachium smithi for Myanmar

Catalogue of amphibian types in the collection of the Zoological Survey of India

The amphibian types in the collection of the National Zoological Collection, maintained by the Zoological Survey of India (ZSI), Kolkata (Calcutta), as well as those held by the regional stations at Dehra Dun and Chennai, are listed, up to 1 September 2000. The list includes many historical specimens collected and/or described by pioneering European naturalists, including Edward Blyth, Thomas Jerdon, William Blanford, William Theobald, Ferdinand Stoliczka, Nelson Annandale, and John Anderson, as well as those more recently described from expeditions to the Nicobar Islands, Arunachal Pradesh and Kerala, by the staff of the ZSI during the present century. The annotated list includes original citations, registration numbers, nature of types, and present status of every taxon. Additional remarks are provided where necessary. A total of 346 type specimens of amphibians are represented, including those representing 105 anuran species, one caudate species and nine apodan species, from Pakistan, India, Sri Lanka, Myanmar, China, Malaysia, and Indonesia. Syntypes from the original type series of two name-bearing taxa have lost their type status through the designation of lectotypes. In addition, the types of 39 name-bearing taxa described by the staff and members of the Asiatic Society of Bengal cannot be located in the ZSI collection

Microbial transformation of xenobiotics for environmental bioremediation

The accumulation of recalcitrant xenobiotic compounds is due to continuous efflux from population and industrial inputs that have created a serious impact on the pristine nature of our environment. Apart from this, these compounds are mostly carcinogenic, posing health hazards which persist over a long period of time. Metabolic pathways and specific operon systems have been found in diverse but limited groups of microbes that are responsible for the transformation of xenobiotic compounds.Distinct catabolic genes are either present on mobile genetic elements, such as transposons and plasmids, or the chromosome itself that facilitates horizontal gene transfer and enhances the rapid microbial transformation of toxic xenobiotic compounds. Biotransformation of xenobiotic compounds in natural environment has been studied to understand the microbial ecology, physiology and evolution for their potential in bioremediation. Recent advance in the molecular techniques including DNA fingerprinting, microarrays and metagenomics is being used to augment the transformation of xenobiotic compounds. The present day understandings of aerobic, anaerobic and reductive biotransformation by co-metabolic processes and an overview of latest developments in monitoring the catabolic genes of xenobiotic-degrading bacteria are discussed elaborately in this work. Till date, several reviews have come up, highlighting the problem of xenobiotic pollution, yet a comprehensiveunderstanding of the microbial biodegradation of xenobiotics and its application is in nascent stage. Therefore, this is an attempt to understand the microbial role in biotransformation of xenobiotic compounds in context to the modern day biotechnology

Statistics of leading digits leads to unification of quantum correlations

We show that the frequency distribution of the first significant digits of the numbers in the data sets generated from a large class of measures of quantum correlations, which are either entanglement measures, or belong to the information-theoretic paradigm, exhibit a universal behaviour. In particular, for Haar uniformly simulated arbitrary two-qubit states, we find that the first-digit distribution corresponding to a collection of chosen computable quantum correlation quantifiers tend to follow the first-digit law, known as the Benford's law, when the rank of the states increases. Considering a two-qubit state which is obtained from a system governed by paradigmatic spin Hamiltonians, namely, the XY model in a transverse field, and the XXZ model, we show that entanglement as well as information theoretic measures violate the Benford's law. We quantitatively discuss the violation of the Benford's law by using a violation parameter, and demonstrate that the violation parameter can signal quantum phase transitions occurring in these models. We also comment on the universality of the statistics of first significant digits corresponding to appropriate measures of quantum correlations in the case of multipartite systems as well as systems in higher dimensions.Comment: v1: 11 pages, 5 figures, 2 tables; v2: 11 pages, 6 figures, 2 tables, new results added, extended version of the published pape