247 research outputs found

    The earliest occurrence and remarkable stasis of the family Bostrichidae (Coleoptera: Polyphaga)in Cretaceous Charentes amber.

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    A new fossil species of auger beetle (Coleoptera: Bostrichidae), preserved in mid-Cretaceous (Albian-Cenomanian) amber from south-western France, is described as Stephanopachys vetus Peris, Delclòs et Perrichot sp. n. The species is the earliest fossil bostrichid discovered to date, but is remarkably similar to Recent species of the genus Stephanopachys, supporting long morphological conservation in wood boring beetles. The specimen is fossilized in fully opaque amber and was imaged in 3D using propagation phase-contrast X-ray synchrotron microtomography. Based on the ecology of extant related species habits, it is suggested that S. vetus sp. n. was a primary succession pioneer following wildfires in mid-Cretaceous forests. The fossil record of the family is reviewed

    Evolution of Research into the Management of Family Businesses that are Part of the Instituto de la Empresa Familiar Network of Chairs (1992-2016)

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    ABSTRACT: The family business field of study has grown considerably in recent years in Spain. In fact, it is no exaggeration to say that twenty years ago there was barely any research in this field. In 1992, exactly 25 years ago, a group of family entrepreneurs founded the Instituto de la Empresa Familiar (IEF). IEF created the Chair in Family Business at Spanish universities to foster its inclusion in Business Administration syllabuses and promote its research by Spanish academics. This paper analyses the evolution of research into family businesses carried out by academics who are part of the IEF Network of Chairs, both at international and management level. To do this, the ISI Web of Knowledge database and Scopus were used as sources of information

    Sources of hepatic triglyceride accumulation during high-fat feeding in the healthy rat

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    Hepatic triglyceride (HTG) accumulation from peripheral dietary sources and from endogenous de novo lipogenesis (DNL) was quantified in adult Sprague-Dawley rats by combining in vivo localized 1H MRS measurement of total hepatic lipid with a novel ex vivo 2H NMR analysis of HTG 2H enrichment from 2H-enriched body water. The methodology for DNL determination needs further validation against standard methodologies. To examine the effect of a high-fat diet on HTG concentrations and sources, animals (n = 5) were given high-fat chow for 35 days. HTG accumulation, measured by in vivo 1H MRS, increased significantly after 1 week (3.85 ± 0.60% vs 2.13 ± 0.34% for animals fed on a standard chow diet, P < 0.05) and was maintained until week 5 (3.30 ± 0.60% vs 1.12 ± 0.30%, P < 0.05). Animals fed on a high-fat diet were glucose intolerant (13.3 ± 1.3 vs 9.4 ± 0.8 mM in animals fed on a standard chow diet, for 60 min glycemia after glucose challenge, P < 0.05). In control animals, DNL accounted for 10.9 ± 1.0% of HTG, whereas in animals given the high-fat diet, the DNL contribution was significantly reduced to 1.0 ± 0.2% (P < 0.01 relative to controls). In a separate study to determine the response of HTG to weaning from a high-fat diet, animals with raised HTG (3.33 ± 0.51%) after 7days of a high-fat diet reverted to basal HTG concentrations (0.76 ± 0.06%) after an additional 7 days of weaning on a standard chow diet. These studies show that, in healthy rats, HTG concentrations are acutely influenced by dietary lipid concentrations. Although the DNL contribution to HTG content is suppressed by a high-fat diet in adult Sprague-Dawley rats, this effect is insufficient to prevent overall increases in HTG concentrations. Copyright © 2008 John Wiley & Sons, Ltd

    Improvement of the electrochemical behaviour of Zn-electroplated steel using regenerated Cr(III) passivation baths

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    Conversion coatings based on trivalent chromium are more sensitive to the presence of zinc and iron impurities than the chromate formulations. This fact contributes to a decrease in the quality of passivation and to the generation of a significant amount of hazardous liquid waste. Recently, a new eco-innovative process based on Emulsion Pertraction Technology (EPT) is being implemented at industrial scale for selectively removing Zn and Fe from spent passivation baths in order to enhance the lifetime of the Cr (III) baths. In this study, the effect of Zn and Fe removal on the electrochemical behaviour of Zn-electroplated steel samples was evaluated by means of polarisation curves and electrochemical impedance spectroscopy measurements at open circuit potential conditions in 3.5 g/L NaCl solutions. The main objective was to assess the benefits brought by EPT using electrochemical methods. Cr (III) passivation baths regenerated using the EPT process have been compared to the bath used in a local industry as well as to fresh and spent baths. According to the results, the samples passivated in the EPT regenerated bath showed a significant improvement in their electrochemical behaviour compared to the samples passivated in the spent baths. This study concluded the suitability of EPT for regenerating Cr (III) passivation baths

    Impactos ambientales del ciclo de vida de las baldosas cerámicas: análisis sectorial, identificación de estrategias de mejora y comunicación (I)

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    El artículo analiza el impacto ambiental que generan las baldosas cerámicas mediante el Análisis de Ciclo de Vida (AC) a nivel sectorial en el que participaron más de 50 empresas españolas. Los resultados han servido para la redacción de las Reglas de Categoría de Producto (RCP) para los recubrimientos de materiales cerámicos, necesarias para la edición de Declaraciones Ambientales de Producto. (Debido a la extensión del artículo recogeremos en esta edición la primera parte, correspondiente a la definición de objetivos y alcance del estudio y el análisis del inventario. La segunda parte, que consta de la evaluación de impactos e interpretación, la identificación de estrategias de mejora, la comunicación ambiental y las conclusiones se publicarán en el número 236 de Piscinas XXI).The article analyses the environmental impact of ceramic tiles by means of a sector-level Life Cycle Analysis (LCA) involving over 50 Spanish firms. The findings were then used to draw up the Product Category Rules (PCR) for ceramic coverings, which are needed to be able to issue Environmental Product Declarations. (Due to the length of the paper, in this edition we will include only the first part, which covers the definition of the aims and scope of the study, as well as the inventory analysis. The second part, which comprises the evaluation of the impacts and interpretation, the identification of the improvement strategies, environmental communication and the conclusions, will be published in issue 236 of Piscinas XXI.

    Effect of temperature on passive film formation of UNS N08031 Cr-Ni alloy in phosphoric acid contaminated with different aggressive anions

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    tThe influence of temperature and the effect of aggressive anions on the electrochemical behaviour of UNSN08031 stainless steel in a contaminated phosphoric acid solution were evaluated. Stabilisation of thepassive film was studied by potentiodynamic polarisation curves, potentiostatic tests, electrochemicalimpedance spectroscopy (EIS) measurements, Mott Schottky analysis and X-ray photoelectron spec-troscopy (XPS). The stability of the passive film was found to decrease as temperature increases. The filmformed on the stainless steel surface was a n-type semiconductor and the XPS spectrum revealed thepresence of fluoride ions.Authors express their gratitude to the Ministry of Education of Spain (MHE2011-00202) for its financial support during the stay at University of Manchester, to MAEC of Spain (PCI Mediterraneo C/8196/07, C/018046/08, D/023608/09 and D/030177/10) and to the Generalitat Valenciana (GV/2011/093) for the financial support. The authors would also like to acknowledge the support of the School of Materials at the University of Manchester for providing analytical and technical support for the study.Escrivá Cerdán, C.; Blasco Tamarit, ME.; García García, DM.; García Antón, J.; Akid, R.; Walton, J. (2013). Effect of temperature on passive film formation of UNS N08031 Cr-Ni alloy in phosphoric acid contaminated with different aggressive anions. Electrochimica Acta. 111:552-561. https://doi.org/10.1016/j.electacta.2013.08.040S55256111

    Genome-Wide Analysis of the Yeast Transcriptome Upon Heat and Cold Shock

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    DNA arrays were used to measure changes in transcript levels as yeast cells responded to temperature shocks. The number of genes upregulated by temperature shifts from 30 ℃ to 37℃ or 45℃ was correlated with the severity of the stress. Pre-adaptation of cells, by growth at 37 ℃ previous to the 45℃ shift, caused a decrease in the number of genes related to this response. Heat shock also caused downregulation of a set of genes related to metabolism, cell growth and division, transcription, ribosomal proteins, protein synthesis and destination. Probably all of these responses combine to slow down cell growth and division during heat shock, thus saving energy for cell rescue. The presence of putative binding sites for Xbp1p in the promoters of these genes suggests a hypothetical role for this transcriptional repressor, although other mechanisms may be considered. The response to cold shock (4℃) affected a small number of genes, but the vast majority of those genes induced by exposure to 4 ℃ were also induced during heat shock; these genes share in their promoters cis-regulatory elements previously related to other stress responses

    Total Absorption Spectroscopy Study of 92^{92}Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape

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    The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. 92^{92}Rb makes the dominant contribution to the reactor spectrum in the 5-8 MeV range but its decay properties are in question. We have studied 92^{92}Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.Comment: 6 pages, 3 figure

    Resolving the Sources of Plasma Glucose Excursions following a Glucose Tolerance Test in the Rat with Deuterated Water and [U-13C]Glucose

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    Sources of plasma glucose excursions (PGE) following a glucose tolerance test enriched with [U-13C]glucose and deuterated water were directly resolved by 13C and 2H Nuclear Magnetic Resonance spectroscopy analysis of plasma glucose and water enrichments in rat. Plasma water 2H-enrichment attained isotopic steady-state within 2–4 minutes following the load. The fraction of PGE derived from endogenous sources was determined from the ratio of plasma glucose position 2 and plasma water 2H-enrichments. The fractional gluconeogenic contributions to PGE were obtained from plasma glucose positions 2 and 5 2H-positional enrichment ratios and load contributions were estimated from plasma [U-13C]glucose enrichments. At 15 minutes, the load contributed 26±5% of PGE while 14±2% originated from gluconeogenesis in healthy control rats. Between 15 and 120 minutes, the load contribution fell whereas the gluconeogenic contribution remained constant. High-fat fed animals had significant higher 120-minute blood glucose (173±6 mg/dL vs. 139±10 mg/dL, p<0.05) and gluconeogenic contributions to PGE (59±5 mg/dL vs. 38±3 mg/dL, p<0.01) relative to standard chow-fed controls. In summary, the endogenous and load components of PGE can be resolved during a glucose tolerance test and these measurements revealed that plasma glucose synthesis via gluconeogenesis remained active during the period immediately following a glucose load. In rats that were placed on high-fat diet, the development of glucose intolerance was associated with a significantly higher gluconeogenic contribution to plasma glucose levels after the load
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