Efecto de los grados día de ayuno y del hacinamiento previos al sacrificio sobre el contenido estomacal y respuesta de estrés en trucha arcoíris (Oncorhynchus mykiss)

El ayuno pre-sacrificio es una práctica rutinaria en acuicultura que se lleva a cabo para vaciar el aparato digestivo disminuyendo la cantidad de heces y previniendo una contaminación de la canal (Robb, 2008). Sin embargo, el ayuno puede también incrementar los niveles de estrés de los peces y si estos son lo suficientemente altos afectan a la calidad de la canal (Poli et al., 2005)

Binding energy effects in cascade evolution and sputtering

The MARLOWE model was extended to include a binding energy dependent on the local crystalline order, so that atoms are bound less strongly to their lattice sites near surfaces or associated damage. Sputtering and cascade evolution were studied on the examples of self-ion irradiations of Cu and Au monocrystals. In cascades, the mean binding energy is reduced {approximately}8% in Cu with little dependence on the initial recoil energy; in Au, it is reduced {approximately}9% at 1 keV and {approximately}15% at 100 keV. In sputtering, the mean binding energy is reduced {approximately}8% in Cu and {approximately}15% in Au with little energy dependence; the yields are increased about half as much. Most sites from which sputtered atoms originate are isolated in both metals. Small clusters of such sites occur in Cu, but there are some large clusters in Au, especially in [111] targets. There are always more large clusters with damage-dependent binding than with a constant binding energy, but only a few clusters are compact enough to be regarded as pits

A Conformally Invariant Holographic Two-Point Function on the Berger Sphere

We apply our previous work on Green's functions for the four-dimensional quaternionic Taub-NUT manifold to obtain a scalar two-point function on the homogeneously squashed three-sphere (otherwise known as the Berger sphere), which lies at its conformal infinity. Using basic notions from conformal geometry and the theory of boundary value problems, in particular the Dirichlet-to-Robin operator, we establish that our two-point correlation function is conformally invariant and corresponds to a boundary operator of conformal dimension one. It is plausible that the methods we use could have more general applications in an AdS/CFT context.Comment: 1+49 pages, no figures. v2: Several typos correcte

Hybrid Detergents Facilitate Scalable Charge Reduction and Stabilize Membrane Proteins While Retaining Lipid Interactions

Membrane protein complexes regulate many biological functions, yet they are incredibly challenging to handle. Detergents are a key enabling technology for purification and analysis as they can provide membrane proteins with controlled solubility, stability, and heterogeneity. However, the design criteria for detergents that enable both the purification and analysis of membrane proteins with their associated lipids remain unclear. Here, we leverage the modular nature of nonionic hybrid detergents to chemically tune molecular parameters that are important for maintaining native oligomeric states of membrane protein complexes and copurifying lipids. Tuning the hydrophilic‐lipophilic balance (HLB), and the relative size of a nonionic head in proximity to a tetraethylene glycol headgroup, led to altered charge reduction, retention of protein oligomers and changed the relative degree of copurifying lipids from purification to analysis in a predictable manner. Our findings represent a significant step forward in the investigation of membrane proteins and interactions with lipids

Libraries and open society; Popper, Soros and digital information

This paper examines the role of libraries and information services, in promoting the ‘open society’ espoused by Karl Popper and George Soros. After a brief discussion of the nature of an ‘open society’, the paper covers the role played by provision of knowledge and information, of new technology, particularly the Internet, and of critical thinking and digital literacy in the development of this form of society. Conclusions are drawn for the role of libraries and librarians, with seven general principles suggested: • provision of access to a wide variety of sources without ‘negative’ restriction or censorship • provision of ‘positive’ guidance on sources, based on open and objective criteria • a recognition that a ‘free flow of information’ though essential, is not sufficient • a recognition that provision of factual information, while valuable, is not enough • a need for a specific concern for the effect of new ICTs, and the Internet in particular • promotion of critical thinking and digital literacy • a need for explicit consideration of the ethical values of librarie

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

Computer studies of the scattering of low energy hydrogen ions from polycrystalline solids

Reflection of 50 eV to 10 keV H atoms from polycrystalline Cu, Nb and Au targets has been calculated using the binary collision cascade program MARLOWE. The fractions of particles and energy reflected (backscattered) increase with increasing atomic number of the target and decrease with increasing incident energy. The results indicate that the effects of polycrystallinity are modest, reducing the amorphous reflection coefficients by about 25 percent. The calculations agree quite well with the experimental data for Cu and Au, but are about a factor of two larger than is observed for Nb