934 research outputs found

    Razvoj sustava proizvodnje iberijskih svinja u Španjolskoj

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    Total number of Iberian swine sows in Spain is close to 230.000, giving rise to around 2 mill finished Iberian pigs in 2003. The Iberian swine constitutes a singular breed, strongly adapted to the ecological conditions of the "Dehesa" ecosystem. This breed includes a number of strains, all of them showing low prolific and growth rates, very early maturing fat deposition, and an excellent meat quality, which is valuated in the market according to the fatty acid Drofile (palmitic, stearic, oleic and linoleic acids) of subcutaneous fat. This paper mainly deals with available feeding sources of the "Dehesa" for Iberian pigs, the productive features of this breed and the evolution that feeding and production systems have experienced last years.Ukupan broj krmača iberijske svinje u Španjolskoj iznosi blizu 230 000 pa je prema tome u 2003. god. bilo oko 2 milijuna gotovih iberijskih svinja. Iberijska svinja je rijetka pasmina, dobro prilagođena ekološkim uvjetima ekosustava "Dehesa". Ova pasmina ima brojne značajke koje sve pokazuju nisku stopu plodnosti i rasta, vrlo rano dozrijevanje naslaga masti te izvrsnu kakvoću mesa koje se vrednuje na tržištu prema profilu masne kiseline (palmitinske, stearinske, oleinske i linolne kiseline) potkožne masti. Ovaj se članak uglavnom bavi dostupnim izvorima hranidbe "Dehesa" za iberijske svinje, proiz¬vodnim značajkama ove pasmine i razvojem sustava hranidbe i proizvodnje prošle godine

    Low-pH cement mortar-bentonite perturbations in a small-scale pilot laboratory experiment

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    This article has been published in a revised form in Clay Minerals [http://doi.org/10.1180/clm.2018.16]. This version is free to view and download for private research and study only. Not for re-distribution, re-sale or use in derivative worksA novel method to perform small-scale laboratory experiments that reproduce concrete–bentonite and concrete–groundwater interactions has been developed. Such interfaces will prevail in engineered barrier systems used for isolation of nuclear waste. With the goal of optimizing the experimental method, this work has analysed the geochemical interaction of distilled water, low-pH cement mortar and FEBEX-bentonite for 75 days. Limited but evident reactivity between the materials was observed, mainly decalcification in cement mortar, carbonation at the interface with bentonite and Mg enrichment in bentonite. These results are consistent with the state-of-the-art literature and were used to validate this small-scale pilot laboratory experiment to establish the basis for further studies comparing the behaviour of different buffer and cement materialsThe research leading to these results has received funding from the European Union's Horizon 2020 Research and Training 305 Programme of the EURATOM (H2020-NFRP-2014/2015) under grant agreement n° 662147 (CEBAMA

    Solution of the Kwiecinski evolution equations for unintegrated parton distributions using the Mellin transform

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    The Kwiecinski equations for the QCD evolution of the unintegrated parton distributions in the transverse-coordinate space (b) are analyzed with the help of the Mellin-transform method. The equations are solved numerically in the general case, as well as in a small-b expansion which converges fast for b Lambda_QCD sufficiently small. We also discuss the asymptotic limit of large bQ and show that the distributions generated by the evolution decrease with b according to a power law. Numerical results are presented for the pion distributions with a simple valence-like initial condition at the low scale, following from chiral large-N_c quark models. We use two models: the Spectral Quark Model and the Nambu--Jona-Lasinio model. Formal aspects of the equations, such as the analytic form of the b-dependent anomalous dimensions, their analytic structure, as well as the limits of unintegrated parton densities at x -> 0, x -> 1, and at large b, are discussed in detail. The effect of spreading of the transverse momentum with the increasing scale is confirmed, with growing asymptotically as Q^2 alpha(Q^2). Approximate formulas for for each parton species is given, which may be used in practical applications.Comment: 18 pages, 6 figures, RevTe

    Low Energy Chiral Lagrangian in Curved Space-Time from the Spectral Quark Model

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    We analyze the recently proposed Spectral Quark Model in the light of Chiral Perturbation Theory in curved space-time. In particular, we calculate the chiral coefficients L1,...,L10L_1, ..., L_{10}, as well as the coefficients L11L_{11}, L12L_{12}, and L13L_{13}, appearing when the model is coupled to gravity. The analysis is carried for the SU(3) case. We analyze the pattern of chiral symmetry breaking as well as elaborate on the fulfillment of anomalies. Matching the model results to resonance meson exchange yields the relation between the masses of the scalar, tensor and vector mesons, Mf0=Mf2=2MV=43/NcπfπM_{f_0}=M_{f_2}=\sqrt{2} M_V= 4 \sqrt{3 /N_c} \pi f_\pi. Finally, the large-NcN_c limit suggests the dual relations in the vector and scalar channels, MV=MS=26/NcπfπM_V=M_S= 2 \sqrt{6 /N_c} \pi f_\pi and S1/2=<r2>V1/2=2Nc/fπ=0.59fm^{1/2}_S = < r^2 >^{1/2}_V = 2 \sqrt{N_c} / f_\pi = 0.59 {\rm fm} .Comment: 18 pages, no figure

    Effects of internal molecular degrees of freedom on the thermal conductivity of some glasses and disordered crystals

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    The thermal conductivity κ(T) of the fully ordered stable phase II, the metastable phase III, the orientationally disordered (plastic) phase I, as well as the nonergodic orientational glass (OG) phase, of the glass former cyclohexanol (C 6H 11OH) has been measured under equilibrium vapor pressure within the 2-200 K temperature range. The main emphasis is here focused on the influence of the conformational disorder upon the thermal properties of this material. Comparison of results with those regarding cyanoclyclohexane (C 6H 11CN), a chemically related compound, serves to quantify the role played by the terminal groups -OH and -CN on the phonon scattering processes. The picture that emerges shows that motions of such groups do play a minor role as scattering centers, both within the low-temperature orientationally ordered phases as well as in the OG states. The results are analyzed within the Debye-Peierls relaxation time model for isotropic solids comprising mechanisms for long-wave phonon scattering within the OG and orientational ordered low-temperature phases, as well as others arising from localized short-wavelength vibrational modes as pictured by the Cahill-Pohl model. By means of complementary neutron and Raman scattering we show that in the OG state the energy landscapes for both compounds are very similar. © 2012 American Physical Society.This work was financially supported in part by the Spanish Ministry of Science and Innovation (Grant No. FIS2008-00837) and the Catalan Government (Grant No. 2009SGR-1251)Peer Reviewe

    Functional polymorphisms in the CYP3A4, CYP3A5, and CYP21A2 genes in the risk for hypertension in pregnancy

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    An intronic single nucleotide polymorphism (SNP) in the CYP3A5 gene (CYP3A5*3; SNP rs776746) affects RNA splicing and enzymatic activity. The CYP3A5*3 frequency increased with distance from the equator and natural selection has been proposed to explain the worldwide distribution of this allele. CYP3A activity has been related with the risk for hypertension in pregnancy, a major cause of morbidity and mortality among women, and CYP3A5*3 could reduce the risk for this disease in populations from regions with high sodium and water availability. The CYP3A5 genotype was related with blood pressure in the general population, but the effect on the risk for hypertension in pregnancy has not been evaluated. We compared the allele and genotype frequencies of three functional SNPs in the CYP3A5 (rs776746), CYP3A4 (rs2740574), and CYP21A2 (rs6471) genes between pregnant women who developed hypertension (n=250) or who remained normotensive (control group, n=250). In addition, we sequenced the full CYP3A5 coding sequence in 40 women from the two groups to determine whether some gene variants could explain the risk for hypertensive pregnancies in our population. Allele and genotype frequencies did not differ between hypertensive and normotensive women for the three CYP variants. We did not find CYP3A5 nucleotide changes that could explain a higher risk for hypertension in pregnancy. Our data suggests that the variation in CYP3A5, CYP3A4, and CYP21A2 did not contribute to the risk for hypertension in pregnancy in our populationThe author´s work is supported by a grant from the Spanish Fondo de Investigaciones Sanitarias/Fondos FEDER European Union (ETS PI08/90008)

    Electrical transport studies of quench condensed Bi films at the initial stage of film growth: Structural transition and the possible formation of electron droplets

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    The electrical transport properties of amorphous Bi films prepared by sequential quench deposition have been studied in situ. A superconductor-insulator (S-I) transition was observed as the film was made increasingly thicker, consistent with previous studies. Unexpected behavior was found at the initial stage of film growth, a regime not explored in detail prior to the present work. As the temperature was lowered, a positive temperature coefficient of resistance (dR/dT > 0) emerged, with the resistance reaching a minimum before the dR/dT became negative again. This behavior was accompanied by a non-linear and asymmetric I-V characteristic. As the film became thicker, conventional variable-range hopping (VRH) was recovered. We attribute the observed crossover in the electrical transport properties to an amorphous to granular structural transition. The positive dR/dT found in the amorphous phase of Bi formed at the initial stage of film growth was qualitatively explained by the formation of metallic droplets within the electron glass.Comment: 7 pages, 6 figure

    Mitochondrial DNA and TFAM gene variation in early-onset myocardial infarction: evidence for an association to haplogroup H

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    The main objective of this research was to define the association between common mitochondrial DNA (mtDNA) polymorphisms and mitochondrial transcription A gene (TFAM) variants and myocardial infarction (MI) in patients with atherosclerotic diseased vessels. Ten mitochondrial polymorphisms that defined the nine common European haplogroups were genotyped in 500 male patients with early onset MI (<55 years) and at least one atherosclerotic coronary vessel (angiographically confirmed), and 500 healthy controls. In addition, we searched for DNA variants in the coding region of the TFAM gene and compared patients and controls for the allele and genotype frequencies. Early onset MI was strongly associated with male gender and tobacco smoking in our population. MtDNA haplogroup H (defined by allele 7028 C) was significantly more frequent in a first group of patients (n=250) compared to controls (n=300), and the association was confirmed in a second group of only smokers (250 patients and 200 controls). For total patients and controls, we obtained a p=0.002 (OR=1.50; 95% CI= 1.17-1.92) for H vs. the other haplogroups. We found four common TFAM polymorphisms, with allele/genotype frequencies that did not differ between patients and controls. In conclusion, mitochondrial haplogroup H was associated with early onset MI in male smokers. Our work supported a role for the mtDNA variation in the risk for atherosclerosis and ischemic associated events, likely due to differences in mitochondrial function and reactive oxygen production between the different haplogroups.Acknowledgements. This work was supported by grants from the Spanish Fondo de Investigaciones Sanitarias-Fondos FEDER European Union (FIS-06/0214; 09-00172), and Red de Investigación Renal-REDINREN (RD06/0016). MP is the recipient of a predoctoral fellowship from FICYT

    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

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    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
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