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This note analyses on the long wavelength dynamics of a two horizon analogue black hole system in one spatial dimension. By introducing an effective scalar-dilaton model we show that closed form expressions can be obtained for the time-dependent Hawking flux and the energy density of the Hawking radiation. We show that, in the absence superluminal modes, there is a vacuum instability. This instability is recognisable to relativists as the analogue to the destabilisation of the Cauchy horizon of a black hole due to vacuum polarization., Comment: 12 pages, 6 figures

Particle production from the vacuum is a remarkable aspect of particle physics. Prime examples are the Schwinger process of particle production in strong electric fields and the Hawking process of particle production from black holes. These processes can be viewed as quantum tunnelling of particles from the vacuum. The tunnelling approach, and the closely related instanton or complex path approaches, are reviewed here with emphasis on paths in the complex coordinate plane. The method is applied to particle production from a black hole in a magnetic field, where ultra-high energy charged particles are produced., Comment: 18 pages, 12 figures. Conference talk for "Avenues of QFT in Curved Spacetime"

Additional file 2: Table S2. Data extraction form, including the extracted data from our systematic review.

Additional file 1: Table S1. Clinical and biochemical information from the 2 cases of suspected mesalazine induced AIN at Alder Hey Children’s Hospital.

We perform an analysis of the supercooled state in an analogue of an early universe phase transition based on a one dimensional, two-component Bose gas with time-dependent interactions. We demonstrate that the system behaves in the same way as a thermal, relativistic Bose gas undergoing a first order phase transition. We propose a way to prepare the state of the system in the metastable phase as an analogue to supercooling in the early universe. While we show that parametric resonances in the system can be suppressed by thermal damping, we find that the theoretically estimated thermal damping in our model is too weak to suppress the resonances for realistic experimental parameters. However, we propose that experiments to investigate the effective damping rate in experiments would be worthwhile., Comment: 21 pages, 5 figures

Heterochronic genes control the timing of developmental events during four C. elegans larval stages. They encode for proteins and miRNA that control them. Mutations in heterochronic genes can cause skipping or reiteration of cell fates associated with certain larval stages (L1 through L4).lin-28 and lin-46 are two well-studied heterochronic genes.lin-28 acts early in larval development and controls what happens in many tissues during the L2 stage: if it is missing or down-regulated too soon, L2-specific events are skipped. If it is not down-regulated on time, L2-specific events are repeated. This seems to be the sole function of lin-28 in C. elegans. lin-46 works at the same time and controls L2 events in the opposite way: When lin-46 is missing, L2-specific events are sometimes repeated. Interestingly, a lin-28; lin-46 double null mutant, where both genes are inactive, develops nearly perfectly normally.An important question is the conservation of roles of the heterochronic genes in the evolution. lin-28 homologs were studied in the fruit fly, clawed frog, zebrafish, mouse, and human. lin-28 is associated with the early developmental stages and undifferentiated cells and downregulated on the way to the differentiation. LIN-28 in C. elegans and C. briggsae has an 89% identity with the accumulation of mutations within the first 80 amino acids.The aim was to create mutations in lin-28 in lin-46 of C. briggsae and determine (1) whether they produce the same phenotypes as in C. elegans, and (2) determine whether they genetically suppress each other, as in C. elegansSeveral mutant alleles were created by injecting worms with Cas9 protein and in-vitro transcribed guide RNAs.Two frameshift alleles of Cb-lin-28 which are likely nulls. One 3’UTR deletion of Cb-lin-28 was obtained which likely affects a miRNA binding site, causing a gain-of-function (gf) allele. Two frameshift mutation of Cb-lin-46 were obtained, which are also likely nulls.

ATP-sensitive potassium channels (KATP channels) are critical nutrient sensors in many mammalian tissues. In the pancreas, KATP channels are essential for coupling glucose metabolism to insulin secretion. While orthologous genes for many components of metabolism–secretion coupling in mammals are present in lower vertebrates, their expression, functionality and ultimate impact on body glucose homeostasis are unclear. In this paper, we demonstrate that zebrafish islet β-cells express functional KATP channels of similar subunit composition, structure and metabolic sensitivity to their mammalian counterparts. We further show that pharmacological activation of native zebrafish KATP using diazoxide, a specific KATP channel opener, is sufficient to disturb glucose tolerance in adult zebrafish. That β-cell KATP channel expression and function are conserved between zebrafish and mammals illustrates the evolutionary conservation of islet metabolic sensing from fish to humans, and lends relevance to the use of zebrafish to model islet glucose sensing and diseases of membrane excitability such as neonatal diabetes.

Casimir forces from fermions in an extra dimension can stabilise Randall-Sundrum models. Contrary to previous expectations, the stabilisation can produce large electroweak hierarchies without fine tuning. The Casimir stabilisation occurs in the same five-dimensional fermion models which have been found to give the observed fermion mass hierarchies. This is shown for masses generated by the Higgs mechanism and by a Higgsless symmetry breaking mechanism, where new light Kaluza-Klein states are presented, Comment: LaTeX 4 pages

Here, we present the complete genome sequence of Streptomyces sp. strain CCM_MD2014 (phylum Actinobacteria), isolated from surface soil in Woods Hole, MA. Its single linear chromosome of 8,274,043 bp in length has a 72.13% G+C content and contains 6,948 coding sequences.

Here, we present the complete genome sequence of Streptomyces sp. strain CCM_MD2014 (phylum Actinobacteria), isolated from surface soil in Woods Hole, MA. Its single linear chromosome of 8,274,043 bp in length has a 72.13% G+C content and contains 6,948 coding sequences.

Stability of the Higgs vacuum during early universe inflation is dependent on how the Higgs couples to the spacetime curvature. Limits on the curvature coupling parameter at the electroweak scale $��_{EW}$ are shown to be consistent only when quantum gravity effects are included and a covariant quantisation procedure, such as Vilkovisky-DeWitt, is adopted. Stability requires $��_{EW}>-0.03$ for a top quark mass $M_t=173.34\,{\rm GeV}$., 5 pages, 3 figures, RevTex

Loss of functional β-cell mass is a hallmark of type 1 and type 2 diabetes, and methods for restoring these cells are needed. We have previously reported that overexpression of the homeodomain transcription factor NK6 homeobox 1 (Nkx6.1) in rat pancreatic islets induces β-cell proliferation and enhances glucose-stimulated insulin secretion, but the pathway by which Nkx6.1 activates β-cell expansion has not been defined. Here, we demonstrate that Nkx6.1 induces expression of the nuclear receptor subfamily 4, group A, members 1 and 3 (Nr4a1 and Nr4a3) orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated β-cell proliferation. Consistent with this finding, global knockout of Nr4a1 results in a decrease in β-cell area in neonatal and young mice. Overexpression of Nkx6.1 and the Nr4a receptors results in increased expression of key cell cycle inducers E2F transcription factor 1 and cyclin E1. Furthermore, Nkx6.1 and Nr4a receptors induce components of the anaphase-promoting complex, including ubiquitin-conjugating enzyme E2C, resulting in degradation of the cell cycle inhibitor p21. These studies identify a unique bipartite pathway for activation of β-cell proliferation, suggesting several unique targets for expansion of functional β-cell mass.

The quantisation of scalar field theory and Einstein gravity is investigated using a fully covariant background field formalism, including Vilkovisky-DeWitt corrections. The one-loop divergences, which are relevant for the consistency of the low-energy effective theory, differ substantially from non-covariant calculations. The results are applied to the effective action of Higgs inflation, with a non-minimal gravity coupling parameter $\xi$, where the use of a formalism which is independent of field redefinitions is particularly important. Consistency of the one-loop effective action requires the cut-off $\Lambda, Comment: 11 pages, LaTeX. v2 corrects some coefficients

This short note considers the effects of quantum theory on the linear evolution of the magnetic fields during and after inflation. The analysis appears to show that the magnetic fields decay exponentially in the high-temperature radiation era due to a combination of ohmic dissipation and vacuum polarisation., Comment: This paper has been withdrawn by the author. The paper only considers the omega>k regime, but the undamped modes have omega

The peptide uroguanylin regulates electrolyte transport in the intestine and kidney. Human uroguanylin has two conformations that can be stably isolated, owing to their slow interconversion rate. The A isomer potently activates the guanylate cyclase-C receptor found primarily in the intestine. The B isomer, by contrast, is a very weak agonist of this receptor, leading to a widely-held assumption that it is physiologically irrelevant. We show here, however, that human uroguanylin B has potent natriuretic activity in the kidney. Interestingly, uroguanylin A and B both induce saliuretic responses, but the activity profiles for the two peptides differ markedly. The uroguanylin B dose-response curve is sigmoidal with a threshold dose near 10 nmol/kg body weight, whereas uroguanylin A has a comparable threshold, but a bell-shaped dose-response curve. Additionally, our study indicates a unique interplay between the A and B isoforms, such that the A form at high concentrations antagonizes the natriuretic action of the B form. These data show that the kidney contains a uroguanylin receptor whose pharmacological profile does not match that of the well-defined intestinal uroguanylin receptor (guanylate cyclase-C), an observation consistent with previous studies showing that the kidney of the guanylate cyclase-C knockout mouse remains responsive to uroguanylin. The results presented here also support the unconventional notion that distinct conformations of a single endocrine peptide can elicit different responses in different tissues.

Dissipative effects can lead to a friction term in the equation of motion for an inflaton field during the inflationary era. The friction term may be linear and localised, in which case it is described by a dissipation coefficient. The dissipation coefficient is calculated here in a supersymmetric model with a two stage decay process in which the inflaton decays into a thermal gas of light particles through a heavy intermediate. At low temperatures, the dissipation coefficient $\propto T^3$ in a thermal approximation. Results are also given for a non-equilibrium anzatz. The dissipation coefficient is consistent with a warm inflationary regime for moderate ($\sim 0.1$) values of the coupling constants., Comment: 21 pages, 11 figures, ReVTeX

This paper considers eleven dimensional supergravity on a manifold with boundary and the theories related to heterotic $M$-theory, in which the matter is confined to the boundary. New low energy actions and boundary conditions on supergravity fields are derived. Previous problems with infinite constants in the action are overcome. The new boundary conditions are shown to be consistent with supersymmetry, and their role in the ten dimensional reduction and gaugino condensation is briefly discussed., Comment: 16 pages, ReVTeX, new section on 10D reduction

Based on some recent work of the authors, we focus on the relationship between the Casimir energy of a Majorana spinor field for a Euclidean Einstein universe $S^4\times R$ and for a Euclidean de Sitter brane ($S^4$) embedded in AdS(5). This is for a conformally coupled massless field. Interestingly, the one brane effective potential is zero and the results are equivalent, as for the scalar case, when evaluated on the conformally related cylinder. However, using the actual metric this equivalence no longer holds because a non-trivial contribution from the path integral measure (known as the cocycle function) is non-zero., Comment: Talk given at the 12th Workshop on General Relativity and Gravitation, University of Tokyo, Tokyo, Japan, 25-28 Nov 2002

A generalised canonical formulation of gravity is devised for foliations of spacetime with codimension $n\ge1$. The new formalism retains n-dimensional covariance and is especially suited to 2+2 decompositions of spacetime. It is also possible to use the generalised formalism to obtain boundary contributions to the 3+1 Hamiltonian., Comment: 18 pages, revtex, 3 postscript figures included

The problem of calculating the effective potential for a real scalar field with a double--well potential is a possible preliminary to understanding symmetry breaking phase transitions in the early universe. It is argued here that it is necessary to include multiple saddle points in the path integral formalism and that quadratic source terms are important. The resulting effective action has a well--defined propagator expansion with a positive mass and gives a new way of understanding high temperature expansions, but the results are equally valid at low or zero temperatures., Comment: 13 pages, NCL93-TP8 (REVTEX)

Some indication of conditions that are necessary for the formation of black holes from the collision of bubbles during a supercooled phase transition in the the early universe are explored. Two colliding bubbles can never form a black hole. Three colliding bubbles can refocus the energy in their walls to the extent that it becomes infinite., Comment: 12 pages, NCL93-TP13 (RevTeX)

Warm inflation dynamics is fundamentally based on a system-reservoir configuration in which the dynamics is dictated by a fluctuation-dissipation relation. Recent work by Cerioni et. al. (arXiv:0804.0163) examined dissipative dynamics with no associated fluctuation component. Their results, which are heavily dependent on initial conditions, are at odds with results in the warm inflation literature, especially the spectral indices. The inconsistency of their formalism is outlined here and it is shown how this would lead to their erroneous conclusions. It is then shown how, following the correct dynamical equations of warm inflation, the results in the literature are correct., Comment: Comment on arXiv:0804.0163 (3 pages)