1,266 research outputs found
Semen evaluation of two selected lines of rabbit bucks
[EN] Twenty rabbit bucks of 9 months of age were used to evaluate semen quality of two lines of New Zealand rabbit bucks selected for litter size at weaning (A line) and growth rate from weaning to slaughter (R line). The morphological semen characteristics indicated that the A line spermatozoa had greater acrosome integrity (+3.6 percentage units; P<0.01) and smaller sperm head size (for example, ¿1.46 ¿m2 for sperm head area) than in the R line. Seminal functional traits were also significantly higher for the A line (+13.4 percentage units for viability, +10.6 percentage units for hypo-osmotic swelling test (HOST) and +3.3 g/L for seminal plasma protein. However, no differences were detected between lines for motility parameters and seminal plasma protein electrophoretic profiles. Both lines had the same twelve bands with the following molecular weights to the nearest 1 kD: 124, 117, 99, 86, 75, 62, 40, 32, 21, 19, 10 and 6 kD. A relationship (r=0.308 for A line and 0.359 for R line; P<0.01) was found between the integrity of the plasmatic membrane (viability rate) and tail membrane (HOST) of the spermatozoa in the A line, but not in the R line, which had greater sperm head size. There was also a significant positive correlation coefficient between sperm concentration and either viability or some kinetic traits (r=0.567 and 0.575 for VCL, r=0.584 and 0.561 for VSL and r=0.588 and 0.588 for VAP, for A and R lines, respectively; P<0.001). We concluded that the A line seems to have better semen characteristics than the R line. We also found an interesting correlation among the seminal morphological, functional and kinetic traits, which could possibly be used to facilitate semen evaluation.Hosam M. Safaa was supported by a grant from ICSC-World Laboratory, Switzerland. This work has been supported by the Spanish Research Project (CICYT AGL2004-02710/GAN). The authors are indebted to F. Marco-Jiménez, Universidad Politécnica de Valencia, Valencia, Spain, and G.M.K. Mehaisen, Department of Animal Production, Faculty of Agricultural, Cairo University, Giza, Egypt, for their excellent cooperation throughout this study and to D.A.A. El-Sayed, Faculty of Agricultural, Cairo University, Giza, Egypt, for her help in preparing the manuscript.Safaa, H.; Vicente, J.; Lavara, R.; Viudes De Castro, M. (2008). Semen evaluation of two selected lines of rabbit bucks. World Rabbit Science. 16(3). doi:10.4995/wrs.2008.62216
Discreteness of the spectrum of the compactified D=11 supermembrane with non-trivial winding
We analyze the Hamiltonian of the compactified D=11 supermembrane with
non-trivial central charge in terms of the matrix model constructed recently by
some of the authors. Our main result provides a rigorous proof that the quantum
Hamiltonian of the supersymmetric model has compact resolvent and thus its
spectrum consists of a discrete set of eigenvalues with finite multiplicity.Comment: 16 pages, final versio
Does the inclusion of protease inhibitors in the insemination extender affect rabbit reproductive performance?
[EN] The bioavailability of buserelin acetate when added to the seminal dose appears to be determined by the activity of the existing aminopeptidases. Thus, the addition of amino peptidase inhibitors to rabbit semen extenders could be a solution to decrease the hormone degradation. This study was conducted to evaluate the effect of the protease activity inhibition on rabbit semen quality parameters and reproductive performance after artificial insemination. Seminal quality was not affected by the incubation with protease inhibitors, being the values of motility, viability, and acrosome integrity not significantly different between the protease inhibitors and the control group. In addition, seminal plasma aminopeptidase activity was inhibited in a 55.1% by the protease inhibitors. On the other hand, regarding the effect of protease inhibitors on reproductive performance, our results showed that the presence of protease inhibitors affected the prolificacy rate (9.2 +/- 0.26 and 9.3 +/- 0.23 vs. 8.2 +/- 0.22 total born per litter for negative control, positive control, and aminopeptidase inhibitors group, respectively; P < 0.05), having this group one kit less per delivery. We conclude that the addition of a wide variety of protease inhibitors in the rabbit semen extender negatively affects prolificacy rate. Therefore, the development of new extenders with specific aminopeptidase inhibitors would be one of the strategies to increase the bioavailability of GnRH analogues without affecting the litter size. (C) 2016 Elsevier Inc. All rights reserved.This research was supported in part by the RTA2013-00058-00-00 from INIA, the European Social Fund and the European FEDER Funds. L Casares-Crespo is supported by a scholarship from Institute Valenciano de Investigaciones Agrarias (IVIA) and the European Social Fund.Casares-Crespo, L.; Vicente Antón, JS.; Talavan, A.; Viudes De Castro, MP. (2016). Does the inclusion of protease inhibitors in the insemination extender affect rabbit reproductive performance?. Theriogenology. 85(5):928-932. doi:10.1016/j.theriogenology.2015.10.044S92893285
Educación y cooperación para el desarrollo mediante estándares universales de accesibilidad
II FORO «IBEROAMÉRICA EN LA ESCENA ECONÓMICA INTERNACIONAL: INVERSIONES Y EDUCACIÓN PARA EL DESARROLLO». UNIVERSIDAD REY JUAN CARLOS, MADRID (ESPAÑA), 14 DE DICIEMBRE DE 200
Accesibilidad a Internet: requisitos para la calidad en la docencia e investigación
A good Internet platform for teaching and research must be accessible, independently of the computer platform used, language and other peculiarities (personal or external). This work analyzes the current limitations of Internet access, as well as the potentialities that would represent an access being truly independent of the computer platform, discapacities, availability and speed of access, language and legislation. Thus, the benefits for a more accesible network for lecturing and investigation, overcoming the geographic location or possible discapacity, would be immediate and would have a broad impact spectrum. A more accesible Internet would enhace not only the dissemination of the information, approaching us to the 'global village', but also others aspects like university principles and values that sould be considered: an improvement of the equality of opportunities and the access to the culture and the education, that are the basis of the progress and the individual and collective liberties.Una buena plataforma de docencia e investigación en la red debe ser accesible, independientemente del entorno informático, idioma y condicionantes( personales o externos). Es este trabajo se analizan, por una parte, las limitaciones actuales que se presentan en el acceso a Internet, y por otra las potencialidades que tendría un acceso un acceso independiente de las plataforma informáticas, discapacidades, disponibilidad y velocidad de acceso, idioma y legislación. Así, los beneficios para la docencia y la investigación de una red más accesible, por encima de la localización geográfica o posible discapacidad, serán inmediatos y redundaría en otros campos. Una Internet más accesible abriría una nueva vía no sólo para la difusión de la información, acercándonos a la 'aldea global', sino también para otros aspectos de lo que entenderemos como principios y valores universitarios y que deben ser considerados: una mejora en la igualdad de oportunidades y en el acceso a la cultura y la formación, que son las bases del progreso y de las libertades tanto individuales como colectivas
Progress in Identifying High Nature Value Montados: Impacts of Grazing on Hardwood Rangeland Biodiversity
Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands
known as montados are often considered high nature value (HNV) farming systems, and as such, they may be
deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is
known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems,
due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity.
Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and
their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On
the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated
analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and
structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data,
such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results
show no overall biodiversity variation as a result of different management practices. However, different groups
of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration
in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired
SOBRINA Spanish study-analysing the frequency, cost and adverse events associated with overuse in primary care: protocol for a retrospective cohort study
Introduction Several institutions and quality national agencies have fostered the creation of recommendations on what not to do to reduce overuse in clinical practice. In primary care, their impact has hardly been studied. The frequency of adverse events (AEs) associated with doing what must not be done has not been analysed, either. The aim of this study is to measure the frequency of overuse and AEs associated with doing what must not be done (commission errors) in primary care and their cost. Methods and analysis A coordinated, multicentric, national project. A retrospective cohort study using computerised databases of primary care medical records from national agencies and regional health services will be conducted to analyse the frequency of the overuse due to ignore the do-not-do recommendations, and immediately afterwards, depending on their frequency, a representative random sample of medical records will be reviewed with algorithms (triggers) that determine the frequency of AEs associated with these recommendations. Cost will determine by summation of the direct costs due to the consultation, pharmacy, laboratory and imaging activities according to the cases. Ethics and dissemination The study protocol has been approved by the Ethics Committee of Primary Care Research of the Valencian Community. We aim to disseminate the findings through international peerreviewed journals and on the website (http://www. nohacer. es/). Outcomes will be used to incorporate algorithms into the electronic history to assist in making clinical decisions
Measurements of the reaction of antiproton annihilation at rest at three hydrogen target densities
The proton-antiproton annihilation at rest into the final state
was measured for three different target densities: liquid hydrogen, gaseous
hydrogen at NTP and at a low pressure of 5 mbar. The yield of this reaction in
the liquid hydrogen target is smaller than in the low-pressure gas target. The
branching ratios of the channel were calculated on the basis of
simultaneous analysis of the three data samples. The branching ratio for
annihilation into from the protonium state turns out to be
about ten times smaller as compared to the one from the state.Comment: 10 pages, 3 Postscript figures. Accepted by Physics Letters
New data on OZI rule violation in bar{p}p annihilation at rest
The results of a measurement of the ratio R = Y(phi pi+ pi-) / Y(omega pi+
pi-) for antiproton annihilation at rest in a gaseous and in a liquid hydrogen
target are presented. It was found that the value of this ratio increases with
the decreasing of the dipion mass, which demonstrates the difference in the phi
and omega production mechanisms. An indication on the momentum transfer
dependence of the apparent OZI rule violation for phi production from the 3S1
initial state was found.Comment: 11 pages, 3 PostScript figures, submitted to Physics Letter
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