703 research outputs found

    Sustaining productivity of tropical red snappers using new monitoring and reference points

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    OBJECTIVES: 1. Analyse current monitoring and logbook data sets, as well as survey and other information,to establish whether these data provide sufficient power to develop critical indicators of fishery performance. 2. Provide a risk analysis that examines the use of age structure and catch rate information for development of critical indicators, and response rules for those criteria, in the absence of other fishery information. 3. Develop a monitoring program that uses commercial vessels from the fishery to provide independent data

    Sensory traits, color, and shelf life of low-dose irradiated, precooked, ground beef patties

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    Irradiation did not influence bitter, bloody, burnt, chemical, fat-like, juiciness, liver-like, beef identity, metallic, rancid, sour, sweet, and toughness flavor/textural attributes, beef aroma, or off-odor in precooked ground beef patties. Irradiation slightly increased the animal hair flavor note, but intensity levels were <1 on the 15-point sensory scale. Except for 10% fat non-irradiated controls, reheated precooked patties had a slight sour, ammonia-like, top note. Irradiation at 3.5 kilograys (kGy) increased external redness in vacuum-packaged patties, but not in aerobic packages. Aerobic packaging with or without irradiation decreased external precooked redness. Oxidative rancidity increased when patties were irradiated in aerobic but not in vacuum packages. Reduction of oxygen in vacuum bags extended the shelf life of the precooked ground beef patties, at least in terms of oxidative rancidity. Precooking ground beef patties, irrespective of irradiation or packaging type, posed sensory disadvantages, and improvements to the precooking process are needed before irradiating at low-dose levels is appropriate

    Sensory traits, color, and shelf life of low-dose irradiated, raw, ground beef patties

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    Irradiation of raw ground beef patties had minimal effects on flavor and aroma of patties after cooking. Oxidative rancidity increased when patties were irradiated in aerobic but not in vacuum packages. Irradiation of vacuum-packaged ground beef patties produced a more stable color. In both packaging types, irradiation significantly reduced microbial growth during storage

    The Teachers’ voice in Saxony-Anhalt: perspectives on transition from primary to secondary school

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    Preparation and provision for transition between primary and secondary school get mixed reviews across all subjects. The literature suggests that modern languages is an area deserving particular attention. There are examples of good practice in transition but the general picture is, at best, patchy. Researchers (eg Blondin et al., 1998; Hill et al., 1998; Rosenbusch, 1995) confirm that this is not a country-specific issue but one which crosses borders of countries and continents. The purpose of this article is to report on how schools in Saxony-Anhalt, Germany, have dealt with the challenge of transition. The outcomes of semi-structured interviews with 25 secondary schools teachers suggest that many of the problems in Saxony-Anhalt are the same as for other countries, not least in relation to communication between secondary and primary schools and the exchange of information on individual pupils. Our German neighbours offer models of good practice in relation to Continuing Professional Development, clearly defined and understood teaching content and methods and the avoidance of any need for pupils to start their modern language learning experience afresh on arrival at secondary school

    Can induced gravity isotropize Bianchi I, V, or IX Universes?

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    We analyze if Bianchi I, V, and IX models in the Induced Gravity (IG) theory can evolve to a Friedmann--Roberson--Walker (FRW) expansion due to the non--minimal coupling of gravity and the scalar field. The analytical results that we found for the Brans-Dicke (BD) theory are now applied to the IG theory which has ω1\omega \ll 1 (ω\omega being the square ratio of the Higgs to Planck mass) in a cosmological era in which the IG--potential is not significant. We find that the isotropization mechanism crucially depends on the value of ω\omega. Its smallness also permits inflationary solutions. For the Bianch V model inflation due to the Higgs potential takes place afterwads, and subsequently the spontaneous symmetry breaking (SSB) ends with an effective FRW evolution. The ordinary tests of successful cosmology are well satisfied.Comment: 24 pages, 5 figures, to be published in Phys. Rev. D1

    Domain Wall Spacetimes: Instability of Cosmological Event and Cauchy Horizons

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    The stability of cosmological event and Cauchy horizons of spacetimes associated with plane symmetric domain walls are studied. It is found that both horizons are not stable against perturbations of null fluids and massless scalar fields; they are turned into curvature singularities. These singularities are light-like and strong in the sense that both the tidal forces and distortions acting on test particles become unbounded when theses singularities are approached.Comment: Latex, 3 figures not included in the text but available upon reques

    Stress corrosion cracking in Al-Zn-Mg-Cu aluminum alloys in saline environments

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    Copyright 2013 ASM International. This paper was published in Metallurgical and Materials Transactions A, 44A(3), 1230 - 1253, and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.Stress corrosion cracking of Al-Zn-Mg-Cu (AA7xxx) aluminum alloys exposed to saline environments at temperatures ranging from 293 K to 353 K (20 °C to 80 °C) has been reviewed with particular attention to the influences of alloy composition and temper, and bulk and local environmental conditions. Stress corrosion crack (SCC) growth rates at room temperature for peak- and over-aged tempers in saline environments are minimized for Al-Zn-Mg-Cu alloys containing less than ~8 wt pct Zn when Zn/Mg ratios are ranging from 2 to 3, excess magnesium levels are less than 1 wt pct, and copper content is either less than ~0.2 wt pct or ranging from 1.3 to 2 wt pct. A minimum chloride ion concentration of ~0.01 M is required for crack growth rates to exceed those in distilled water, which insures that the local solution pH in crack-tip regions can be maintained at less than 4. Crack growth rates in saline solution without other additions gradually increase with bulk chloride ion concentrations up to around 0.6 M NaCl, whereas in solutions with sufficiently low dichromate (or chromate), inhibitor additions are insensitive to the bulk chloride concentration and are typically at least double those observed without the additions. DCB specimens, fatigue pre-cracked in air before immersion in a saline environment, show an initial period with no detectible crack growth, followed by crack growth at the distilled water rate, and then transition to a higher crack growth rate typical of region 2 crack growth in the saline environment. Time spent in each stage depends on the type of pre-crack (“pop-in” vs fatigue), applied stress intensity factor, alloy chemistry, bulk environment, and, if applied, the external polarization. Apparent activation energies (E a) for SCC growth in Al-Zn-Mg-Cu alloys exposed to 0.6 M NaCl over the temperatures ranging from 293 K to 353 K (20 °C to 80 °C) for under-, peak-, and over-aged low-copper-containing alloys (~0.8 wt pct), they are typically ranging from 20 to 40 kJ/mol for under- and peak-aged alloys, and based on limited data, around 85 kJ/mol for over-aged tempers. This means that crack propagation in saline environments is most likely to occur by a hydrogen-related process for low-copper-containing Al-Zn-Mg-Cu alloys in under-, peak- and over-aged tempers, and for high-copper alloys in under- and peak-aged tempers. For over-aged high-copper-containing alloys, cracking is most probably under anodic dissolution control. Future stress corrosion studies should focus on understanding the factors that control crack initiation, and insuring that the next generation of higher performance Al-Zn-Mg-Cu alloys has similar longer crack initiation times and crack propagation rates to those of the incumbent alloys in an over-aged condition where crack rates are less than 1 mm/month at a high stress intensity factor

    Multi-Objective Optimization with an Adaptive Resonance Theory-Based Estimation of Distribution Algorithm: A Comparative Study

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    Proceedings of: 5th International Conference, LION 5, Rome, Italy, January 17-21, 2011.The introduction of learning to the search mechanisms of optimization algorithms has been nominated as one of the viable approaches when dealing with complex optimization problems, in particular with multi-objective ones. One of the forms of carrying out this hybridization process is by using multi-objective optimization estimation of distribution algorithms (MOEDAs). However, it has been pointed out that current MOEDAs have a intrinsic shortcoming in their model-building algorithms that hamper their performance. In this work we argue that error-based learning, the class of learning most commonly used in MOEDAs is responsible for current MOEDA underachievement. We present adaptive resonance theory (ART) as a suitable learning paradigm alternative and present a novel algorithm called multi-objective ART-based EDA (MARTEDA) that uses a Gaussian ART neural network for model-building and an hypervolume-based selector as described for the HypE algorithm. In order to assert the improvement obtained by combining two cutting-edge approaches to optimization an extensive set of experiments are carried out. These experiments also test the scalability of MARTEDA as the number of objective functions increases.This work was supported by projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029-C02-02.Publicad

    Psychological interventions for vaccine injections in young children 0 to 3 years: Systematic review of randomized controlled trials and quasi-randomized controlled trials

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    Background: This systematic review evaluated the effectiveness of distraction for reducing infant distress during vaccinations in young children aged 0 to 3 years. Design/Methods: Database searches identified relevant randomized and quasi-randomized controlled trials. Three separate clinical questions related to variants of the psychological strategy of distraction (directed video; directed toy; nondirected toy) were pursued. Distress was identified as the critical outcome to assess the benefits of distraction and extracted from relevant trials. Distress was analyzed by phase of procedure (distress preprocedure; distress acute; distress recovery; idiosyncratic phases based on some or all of the 3 aforementioned phases). Results: Ten studies were included in the review. Significant results are presented herein. For directed video distraction, moderate quality evidence suggested that distress was lowered in the treatment group standardized mean difference (SMD -0.68 lower [95% confidence interval (CI), -1.04 to -0.32]) for the acute+recovery phase as well as the preprocedure phase (SMD -0.49 lower [95% CI, -7.6 to -0.22]). For directed toy distraction, the analysis of low-quality evidence for a combined preprocedure+acute+ recovery phase of distress (analysis n=81), suggested that distress was lowered in the treatment group (SMD -0.47 lower [95% CI, -0.91 to -0.02]). An effect for nondirected toy distraction was also seen, analyzing very-low-quality evidence, for the acute distress phase (n=290; SMD -0.93 lower [95% CI, -1.86 to 0.00]). Conclusion: Generally low-quality to very-low-quality evidence suggests that there may be an effect of directed (toy and video) and nondirected toy distraction for children aged 0 to 3 years, for certain phases of the vaccination

    A novel approach to isolating improved industrial interspecific wine yeasts using chromosomal mutations as potential markers for increased fitness

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    Wine yeast breeding programs utilizing interspecific hybridization deliver cost-effective tools to winemakers looking to differentiate their wines through the development of new wine styles. The addition of a non-Saccharomyces cerevisiae genome to a commercial wine yeast can generate novel phenotypes ranging from wine flavor and aroma diversity to improvements in targeted fermentation traits. In the current study we utilized a novel approach to screen isolates from an evolving population for increased fitness in a S. cerevisiae × S. uvarum interspecific hybrid previously generated to incorporate the targeted phenotype of lower volatile acidity production. Sequential grape-juice fermentations provided a selective environment from which to screen isolates. Chromosomal markers were used in a novel approach to identify isolates with potential increased fitness. A strain with increased fitness relative to its parents was isolated from an early timepoint in the evolving population, thereby minimizing the risk of introducing collateral mutations and potentially undesirable phenotypes. The evolved strain retained the desirable fermentation trait of reduced volatile acidity production, along with other winemaking traits of importance while exhibiting improved fermentation kinetics.Jennifer R. Bellon, Christopher M. Ford, Anthony R. Borneman and Paul J. Chamber
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