Synchrotron radiation from a runaway electron distribution in tokamaks

The synchrotron radiation emitted by runaway electrons in a fusion plasma provides information regarding the particle momenta and pitch-angles of the runaway electron population through the strong dependence of the synchrotron spectrum on these parameters. Information about the runaway density and its spatial distribution, as well as the time evolution of the above quantities, can also be deduced. In this paper we present the synchrotron radiation spectra for typical avalanching runaway electron distributions. Spectra obtained for a distribution of electrons are compared to the emission of mono-energetic electrons with a prescribed pitch-angle. We also examine the effects of magnetic field curvature and analyse the sensitivity of the resulting spectrum to perturbations to the runaway distribution. The implications for the deduced runaway electron parameters are discussed. We compare our calculations to experimental data from DIII-D and estimate the maximum observed runaway energy.Comment: 22 pages, 12 figures; updated author affiliations, fixed typos, added a sentence at the end of section I

Differences in intestinal size, structure, and function contributing to feed efficiency in broiler chickens reared at geographically distant locations

The contribution of the intestinal tract to differences in residual feed intake (RFI) has been inconclusively studied in chickens so far. It is also not clear if RFI-related differences in intestinal function are similar in chickens raised in different environments. The objective was to investigate differences in nutrient retention, visceral organ size, intestinal morphology, jejunal permeability and expression of genes related to barrier function, and innate immune response in chickens of diverging RFI raised at 2 locations (L1: Austria; L2: UK). The experimental protocol was similar, and the same dietary formulation was fed at the 2 locations. Individual BW and feed intake (FI) of chickens (Cobb 500FF) were recorded from d 7 of life. At 5 wk of life, chickens (L1, n = 157; L2 = 192) were ranked according to their RFI, and low, medium, and high RFI chickens were selected (n = 9/RFI group, sex, and location). RFI values were similar between locations within the same RFI group and increased by 446 and 464 g from low to high RFI in females and males, respectively. Location, but not RFI rank, affected growth, nutrient retention, size of the intestine, and jejunal disaccharidase activity. Chickens from L2 had lower total body weight gain and mucosal enzyme activity but higher nutrient retention and longer intestines than chickens at L1. Parameters determined only at L1 showed increased crypt depth in the duodenum and jejunum and enhanced paracellular permeability in low vs. high RFI females. Jejunal expression of IL1B was lower in low vs. high RFI females at L2, whereas that of TLR4 at L1 and MCT1 at both locations was higher in low vs. high RFI males. Correlation analysis between intestinal parameters and feed efficiency metrics indicated that feed conversion ratio was more correlated to intestinal size and function than was RFI. In conclusion, the rearing environment greatly affected intestinal size and function, thereby contributing to the variation in chicken RFI observed across locations

Introduction : analysing English syntax past and present

This book is an exploration of categories, constructions, and change in English syntax. A great many books are published on the syntax of English, both monographs and edited volumes, and yet another may seem unnecessary. However, we felt more than justified in adding to the sizeable literature here for two reasons. The first, to borrow from Richard M. Hogg and David Denison’s justification for A History of the English Language, is that ‘one of the beauties of the language is its ability to show continuous change and flexibility while in some sense remaining the same

Laser scanning microscopy of guided vortex flow in microstructured high-Tc films

We report the visualization of guidance of vortices by artificial microholes (antidots) in superconducting thin films using a low-temperature laser scanning microscope. Previously, guided motion of vortices via tilted rows of antidots in YBa2Cu3O7 films was detected indirectly by using resistive Hall-type measurements. Here we prove that vortices are steered between antidots into a priori chosen direction by imaging of resistive photoresponse with a spatial resolution down to about 1 mu m. We observe predominant paths for vortex motion. Vortices are nucleated and annihilated at antidots, i.e., antidots define starting and ending points of predominant vortex paths. Depending on the misorientation angle between rows of antidots and the current-driven direction of vortex motion, different channels dominate in antidot-guided vortex motion. Our experimental results can be explained by the n-channel model. Finally, we present direct measurements of the local critical currents. This technique can be used as a quantitative method for the analysis of vortex motion in micropatterned thin films. (c) 2006 American Institute of Physics

The rigid amphipathic fusion Inhibitor dUY11 acts through photosensitization of viruses

Copyright © 2014, American Society for Microbiology. All Rights Reserved.Supplemental material for this article may be found at http://dx.doi.org/10.1128 /JVI.02907-13.Rigid amphipathic fusion inhibitors (RAFIs) are lipophilic inverted-cone-shaped molecules thought to antagonize the membrane curvature transitions that occur during virus-cell fusion and are broad-spectrum antivirals against enveloped viruses (Broad-SAVE). Here, we show that RAFIs act like membrane-binding photosensitizers: their antiviral effect is dependent on light and the generation of singlet oxygen (1O2), similar to the mechanistic paradigm established for LJ001, a chemically unrelated class of Broad-SAVE. Photosensitization of viral membranes is a common mechanism that underlies these Broad-SAVE.This work was supported by NIH grants U01 AI070495, U01 AI082100, R01 AI069317, and U54 AI065359 (PSWRCE) (to B.L.) and by Fundação para a Ciência e a Tecnologia-Ministério da Educação e Ciência (Portugal) project DELIN-HIVERA/0002/2013 and fellowship SFRH/BPD/72037/2010 (to N.C.S. and A.H., respectively

H2 as a fuel for flavin- and H2O2-dependent biocatalytic reactions

The soluble hydrogenase from Ralstonia eutropha provides an atom efficient regeneration system for reduced flavin cofactors using H2 as an electron source. We demonstrated this system for highly selective ene-reductase-catalyzed C[double bond, length as m-dash]C-double bond reductions and monooxygenase-catalyzed epoxidation. Reactions were expanded to aerobic conditions to supply H2O2 for peroxygenase-catalyzed hydroxylations.DFG, 284111627, H2-basierende Kaskaden für die Biosynthese von N-HeterocyclenDFG, 405325648, ,Engineering von O2-toleranten Hydrogenasen und ihre physiologischen Auswirkungen in rekombinanten Bakterien im Hinblick auf die Hydrogenase-abhängige NAD(P)H-Regeneration und H2-ProduktionDFG, 390540038, EXC 2008: UniSysCatTU Berlin, Open-Access-Mittel - 202

Characterization of liposomes coated with S-layer proteins from lactobacilli

The stability of liposomes coated with S-layer proteins from Lactobacillus brevis and Lactobacillus kefir was analyzed as a previous stage to the development of a vaccine vehicle for oral administration. The interactions of the different S-layer proteins with positively charged liposomes prepared with soybean lecithin or dipalmitoylphosphatidylcholine were studied by means of the variation of the Z potential at different protein-lipid ratios, showing that both proteins were able to attach in a greater extent to the surface of soybean lecithin liposomes. The capacity of these particles to retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract, pH change and after a thermal shock showed that both S-layer proteins increased the stability of the liposomes in the same magnitude. The non-glycosylated protein from L. brevis protects more efficiently the liposomes at pH 7 than those from L. kefir even without treatment with glutaraldehyde.Centro de Investigación y Desarrollo en Criotecnología de Alimento