Series solutions for a static scalar potential in a Salam-Sezgin Supergravitational hybrid braneworld

The static potential for a massless scalar field shares the essential features of the scalar gravitational mode in a tensorial perturbation analysis about the background solution. Using the fluxbrane construction of [8] we calculate the lowest order of the static potential of a massless scalar field on a thin brane using series solutions to the scalar field's Klein Gordon equation and we find that it has the same form as Newton's Law of Gravity. We claim our method will in general provide a quick and useful check that one may use to see if their model will recover Newton's Law to lowest order on the brane.Comment: 5 pages, no figure

Antileukemic Activity of Nuclear Export Inhibitors that Spare Normal Hematopoietic Cells

Drugs that target the chief mediator of nuclear export, chromosome region maintenance 1 protein (CRM1) have potential as therapeutics for leukemia, but existing CRM1 inhibitors show variable potencies and a broad range of cytotoxic effects. Here, we report the structural analysis and antileukemic activity of a new generation of small-molecule inhibitors of CRM1. Designated selective inhibitors of nuclear export (SINE), these compounds were developed using molecular modeling to screen a small virtual library of compounds against the nuclear export signal (NES) groove of CRM1. The 2.2-Å crystal structure of the CRM1-Ran-RanBP1 complex bound to KPT-251, a representative molecule of this class of inhibitors, shows that the drug occupies part of the groove in CRM1 that is usually occupied by the NES, but penetrates much deeper into the groove and blocks CRM1-directed protein export. SINE inhibitors exhibit potent antileukemic activity, inducing apoptosis at nanomolar concentrations in a panel of 14 human acute myeloid leukemia (AML) cell lines representing different molecular subtypes of the disease. When administered orally to immunodeficient mice engrafted with human AML cells, KPT-251 had potent antileukemic activity with negligible toxicity to normal hematopoietic cells. Thus, KPT-SINE CRM1 antagonists represent a novel class of drugs that warrant further testing in AML patients

Production and decay of evolving horizons

We consider a simple physical model for an evolving horizon that is strongly interacting with its environment, exchanging arbitrarily large quantities of matter with its environment in the form of both infalling material and outgoing Hawking radiation. We permit fluxes of both lightlike and timelike particles to cross the horizon, and ask how the horizon grows and shrinks in response to such flows. We place a premium on providing a clear and straightforward exposition with simple formulae. To be able to handle such a highly dynamical situation in a simple manner we make one significant physical restriction, that of spherical symmetry, and two technical mathematical restrictions: (1) We choose to slice the spacetime in such a way that the space-time foliations (and hence the horizons) are always spherically symmetric. (2) Furthermore we adopt Painleve-Gullstrand coordinates (which are well suited to the problem because they are nonsingular at the horizon) in order to simplify the relevant calculations. We find particularly simple forms for surface gravity, and for the first and second law of black hole thermodynamics, in this general evolving horizon situation. Furthermore we relate our results to Hawking's apparent horizon, Ashtekar et al's isolated and dynamical horizons, and Hayward's trapping horizons. The evolving black hole model discussed here will be of interest, both from an astrophysical viewpoint in terms of discussing growing black holes, and from a purely theoretical viewpoint in discussing black hole evaporation via Hawking radiation.Comment: 25 pages, uses iopart.cls V2: 5 references added; minor typos; V3: some additional clarifications, additional references, additional appendix on the Viadya spacetime. This version published in Classical and Quiantum Gravit

Expression of Interleukin-8 Receptors (CXCR1 and CXCR2) in Premenopausal Women with Recurrent Urinary Tract Infections

The migration of neutrophils through infected tissues is mediated by the CXC chemokines and its receptors (CXCR1 and CXCR2). It has been proposed that a CXCR1 deficiency could confer susceptibility to acute pyelonephritis in children. The objective of the study is to assess the surface expression of CXCR1 and CXCR2 and the existence of polymorphisms in the CXCR1 gene in premenopausal women with recurrent urinary tract infections. The study included 20 premenopausal women with recurrent urinary infections, with normal urinary tracts, and without diseases potentially associated with relapsing urinary infections and 30 controls without previous urinary infections. The levels of CXCR1 and CXCR2 expression on neutrophils were measured and analyzed by flow cytometry by measuring the mean fluorescence intensity (MFI) channel. The promoter and coding regions of the CXCR1 gene were analyzed for the presence of polymorphisms by a sequence-based typing method. Patients with recurrent urinary tract infections exhibited median levels of CXCR1 expression, determined from MFI values, similar to those of the controls. The analysis of CXCR2 showed that patients with recurrent urinary infections had lower median levels of expression, determined from the MFI values, than the controls (P = 0.002, Mann-Whitney U test). No polymorphisms were detected at the promoter or at the exon 1 region of the CXCR1 gene either in the patients or in the controls. Polymorphisms were detected at the exon 2 of CXCR1, but their frequencies did not differ between patients and controls. We have found a low level of CXCR2 expression in patients with recurrent urinary tract infections. These results suggest that a low level of CXCR2 expression may increase the susceptibilities of premenopausal women to urinary tract infections

Modelling HW/SW Co-Designed Processors

This paper presents DARCO, an extensible platform for modelling HW/SW co-designed processors with different guest and host ISAs. Its Emulation Software Layer (ESL) provides staged compilation, which translates and optimizes x86 binaries to run on a PowerPC processor. In addition to the functional models, DARCO provides timing simulators and a powerful debugging toolchain. DARCO has a functional emulation speed of 8 million x86 instructions per second

Linking exposure models to regulatory and sustainability driven frameworks

The assessment of exposure of chemicals to environment and to human via the environment is of major concern for policy and industry and ultimately benefits all citizens. Currently many different types of exposure models are available. However, not all exposure models are designed for the same goal. Exposure assessment of chemicals depends highly on the context. In order to allow a comparison between and selection of exposure models, a transparent and objective framework based on a comprehensive list of scoring factors was developed. A comprehensive list of criteria was set up to structure the characteristics of the exposure tools. These criteria were divided into two categories: general and framework/context specific criteria. The general criteria were transferred into questions and were scored on importance by an expert panel. The framework specific criteria, which are highly context specific, received a score based on their applicability and importance in a certain type of framework. The following regulatory and sustainability driven frameworks were considered: REACH regulation, Plant Protection Products Regulation, Biocidal Product Regulation, environmental/spatial oriented directives (e.g. Water Framework Directive), Food oriented directives (e.g. Food Supplement Directive), product or process certification, site specific impact assessment and sustainability assessment. After scoring the criteria, a list of exposure models (such as EUSES, CalTOX, QUASI, 4FUN, USETOX, GREATER, PEARL, etc.) were evaluated using the Multi-Criteria Decision analysis (MCDA). The MCDA approach is a decision support tool, which allowed us to rank the different exposure models per framework. In conclusion, this methodology is ideally situated to determine the strengths and weaknesses of exposure models and to determine the suitability of a model towards a certain type of framework

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