Can re-entrance be observed in force induced transitions?

A large conformational change in the reaction co-ordinate and the role of the solvent in the formation of base-pairing are combined to settle a long standing issue {\it i.e.} prediction of re-entrance in the force induced transition of DNA. A direct way to observe the re-entrance, i.e a strand goes to the closed state from the open state and again to the open state with temperature, appears difficult to be achieved in the laboratory. An experimental protocol (in direct way) in the constant force ensemble is being proposed for the first time that will enable the observation of the re-entrance behavior in the force-temperature plane. Our exact results for small oligonucleotide that forms a hairpin structure provide the evidence that re-entrance can be observed.Comment: 12 pages and 5 figures (RevTex4). Accepted in Europhys Lett. (2009

Toward 959 nematode genomes

The sequencing of the complete genome of the nematode Caenorhabditis elegans was a landmark achievement and ushered in a new era of whole-organism, systems analyses of the biology of this powerful model organism. The success of the C. elegans genome sequencing project also inspired communities working on other organisms to approach genome sequencing of their species. The phylum Nematoda is rich and diverse and of interest to a wide range of research fields from basic biology through ecology and parasitic disease. For all these communities, it is now clear that access to genome scale data will be key to advancing understanding, and in the case of parasites, developing new ways to control or cure diseases. The advent of second-generation sequencing technologies, improvements in computing algorithms and infrastructure and growth in bioinformatics and genomics literacy is making the addition of genome sequencing to the research goals of any nematode research program a less daunting prospect. To inspire, promote and coordinate genomic sequencing across the diversity of the phylum, we have launched a community wiki and the 959 Nematode Genomes initiative (www.nematodegenomes.org/). Just as the deciphering of the developmental lineage of the 959 cells of the adult hermaphrodite C. elegans was the gateway to broad advances in biomedical science, we hope that a nematode phylogeny with (at least) 959 sequenced species will underpin further advances in understanding the origins of parasitism, the dynamics of genomic change and the adaptations that have made Nematoda one of the most successful animal phyla

Quantum statistics and noncommutative black holes

We study the behaviour of a scalar field coupled to a noncommutative black hole which is described by a $\kappa$-cylinder Hopf algebra. We introduce a new class of realizations of this algebra which has a smooth limit as the deformation parameter vanishes. The twisted flip operator is independent of the choice of realization within this class. We demonstrate that the $R$-matrix is quasi-triangular up to the first order in the deformation parameter. Our results indicate how a scalar field might behave in the vicinity of a black hole at the Planck scale.Comment: 8 pages, no figures, revtex4; in v2 some points are explained in more detail, few typos corrected and one reference adde

HIGGINS: where knowledge acquisition meets the crowds

We present HIGGINS, an engine for high quality Knowl- edge Acquisition (KA), placing special emphasis on its ar- chitecture. The distinguishing characteristic and novelty of HIGGINS lies in its special blending of two engines: An automated Information Extraction (IE) engine, aided by semantic resources, and a game-based, Human Computing engine (HC). We focus on KA from web data and text sources and, in particular, on deriving relationships between enti- ties. As a running application we utilise movie narratives, using which we wish to derive relationships among movie characters

Equipartition of Current in Parallel Conductors on Cooling Through the Superconducting Transition

Our experiments show that for two or more pieces of a wire, of different lengths in general, combined in parallel and connected to a dc source, the current ratio evolves towards unity as the combination is cooled to the superconducting transition temperature Tc, and remains pinned at that value below it. This re-distribution of the total current towards equipartition without external fine tuning is a surprise. It can be physically understood in terms of a mechanism that involves the flux-flow resistance associated with the transport current in a wire of type-II superconducting material. It is the fact that the flux-flow resistance increases with current that drives the current division towards equipartition.Comment: Revised version of J.Phys. Condens.Matter; vol. 18(2006) L143-L147 14 pages including 3 figures; provided an explanation in terms of the physical mechanism of flux flow induced resistance that is proportional to the impressed current. We are adding a simple, physically robust derivation of our equipartition without taking resort to the minimum dissipation principl

Effect of Landauer's blowtorch on the equilibration rate in a bistable potential

Kinetic aspect of Landauer's blowtorch effect is investigated for a model double-well potential with localized heating. Using the supersymmetric approach, we derive an approximate analytical expression for the equilibration rate as function of the strength, width and the position of the hot zone, and the barrier height. We find that the presence of the hot zone enhances the equilibration rate, which is found to be an increasing function of the strength and width of the hot zone. Our calculations also reveal an intriguing result, namely, that placing the hot zone away from the top of the potential barrier enhances the rate more than when it is placed close to it. A physically plausible explanation for this is attempted. The above analytical results are borne out by detailed numerical solution of the associated Smoluchowski equation for the inhomogeneous medium.Comment: 15 pages in LaTeX format and 6 figures in postscript E-Mail : [email protected] [email protected]