1,871 research outputs found
FAM-1 Borehole: first results from the scientific drilling of the Alhama de Murcia Fault, Betic Cordillera, Spain
We present the preliminary results of the borehole FAM-1 a 175 m depth scientific drilling of the Alhama de Murcia fault. The borehole was drilled close to La Torrecilla rambla three km SW of Lorca where the fault zone shearing is more concentrated and it is dominated by well-developed clay rich fault gouge. To select the drilling point and to perform a prognosis of it, three trenches were excavated crossing the fault zone that allowed us to determine the detailed 3D structure of the fault zone. We have collected more than 100 m of unaltered high quality fault rock to be studied using mineralogical and microtectonic analysis, and geomechanical testing that will improve the knowledge of the influence of tectonic microfabric and mineralogy in the seismogenic behavior of the AMF. The borehole FAM-1 and the seismic monitoring borehole FamSis-1 constitute the first stage of a future geological-geophysical observatory for monitoring the activity of the AMF.This research is part of the INTERGEO project: CGL2013-47412-C2-1-P.Peer Reviewe
Effects of land vs. Aquatic plyometric training on vertical jump
El objetivo de este estudio fue comparar los efectos de dos programas de entrenamiento pliométrico (inmersión vs. seco) sobre el salto vertical. 65 hombres fÃsicamente activos fueron asignados aleatoriamente a tres grupos: entrenamiento pliométrico acuático (EPA, n 20), entrenamiento pliométrico (EP, n=20) y grupo control (GC, n=25). Los grupos EPA y EP entrenaron 2 sesiones por semana durante 10 semanas, mientras que GC no realizó entrenamiento alguno. El volumen de entrenamiento fue aumentado desde 10 series de 10 repeticiones en la primera semana hasta 10 series de 55 repeticiones en la última. Tanto EPA como EP aumentaron su rendimiento en CMJ y SJ con respecto al pretest (P≤0,001) sin encontrar diferencias significativas entre grupos, mientras que GC no mostró cambios. Como conclusión, el EPA puede ser un método alternativo a EP ya que ambos producen similares mejoras sobre el salto vertical y el estrés mecánico producido por EPA es menoThe aim of this study was to compare the effects of two plyometric training program (aquatic vs. land) on vertical jump. 65 male physical education students took part in this study and were randomly assigned to three groups: aquatic plyometric training group (APT, n = 20), plyometric training group (PT, n = 20) and control group (CG, n = 25). The training program was performed for 10 weeks with a frequency of 2 sessions per week. Volume was increased from 10 sets of 10 repetitions to 10 sets of 55 repetitions. Both APT and PT increased the performance in CMJ and SJ with respect to pretest (P ≤ .001), whereas CG remained unaltered. No statistically significant difference was observed between APT and PT. In conclusion, APT may be an alternative method to PT, because both training protocols have produced similar gains in the vertical jump, but APT might cause lower mechanical stres
Pore morphology evolution and atom distribution of doped Fe2O3 foams developed by freeze-casting after redox cycling
Chemical looping water splitting systems operate at relatively high
temperatures (450-800 degree C) to produce, purify, or store hydrogen by the
cyclic reduction and oxidation (redox) of a solid oxygen carrier. Therefore, to
improve long-term operation, it is necessary to develop highly stable oxygen
carriers with large specific surface areas. In this work, highly interconnected
doped Fe2O3 foams are fabricated through the freeze-casting technique, and the
aid of a submicrometric camphene-based suspension to prevent Fe sintering and
pore clogging during redox operation. The influence of the dopant elements (Al
and Ce) over the pore morphology evolution, and redox performances are
examined. The use of an Fe2O3 porous structure with initial pore size above 100
microns shows a significant reduction of the sample densification, and the
addition of Al2O3 by the co-precipitation process proves to be beneficial in
preventing the generation of a core-shell structure following redox processing.Comment: 25 pages, 8 figure
Production of new neutron-rich isotopes of heavy elements in fragmentation reactions of U projectiles at 1 A GeV
The production of heavy neutron-rich nuclei has been investigated using cold
fragmentation reactions of U projectiles at relativistic energies. The
experiment performed at the high-resolving-power magnetic spectrometer FRS at
GSI allowed to identify 45 new heavy neutron-rich nuclei: Pt,
Au, Hg, Tl, Pb, Bi,
Po, At, Rn and Fr. The production
cross sections of these nuclei were also determined and used to benchmark
reaction codes that predict the production of nuclei far from stability.Comment: 5 pages, 2 figure
Model definition for genetic evaluation of purebred and crossbred lambs including heterosis
Crossbreeding is a common practice among commercial sheep producers to improve animal performance. However, genetic evaluation of U.S. sheep is performed within breed type (terminal sire, semi-prolific, and western range). While incorporating crossbred records may improve assessment of purebreds, it requires accounting for heterotic and breed effects in the evaluation. The objectives of this study were to: 1) describe the development of a paternal composite (PC) line, 2) determine the effect of direct and maternal heterosis on growth traits of crossbred lambs, 3) estimate (co)variance components for direct and maternal additive, and uncorrelated maternal environmental, effects, and 4) provide an interpretation of the estimates of random effects of genetic groups, and to use those solutions to compare the genetic merit of founding breed subpopulations. Data included purebred and crossbred records on birth weight (BN; n = 14,536), pre-weaning weight measured at 39 or 84 d (WN; n = 9,362) depending on year, weaning weight measured at 123 d (WW; n = 9,297), and post-weaning weight measured at 252 d (PW; n = 1,614). Mean (SD) body weights were 5.3 (1.1), 16.8 (3.9) and 28.0 (7.6), 39.1 (7.2), and 54.2 (8.7) kg for BN, WN (at the two ages), WW, and PW, respectively. In designed experiments, the Siremax, Suffolk, Texel, Polypay, Columbia, Rambouillet, and Targhee breeds were compared within the same environment. Estimates of heterotic effects and covariance components were obtained using a multiple trait animal model. Genetic effects based on founders’ breeds were significant and included in the model. Percent estimates of direct heterosis were 2.89 ± 0.61, 2.60 ± 0.65, 4.24 ± 0.56, and 6.09 ± 0.86, and estimates of maternal heterosis were 1.92 ± 0.87, 4.64 ± 0.80, 3.95 ± 0.66, and 4.04 ± 0.91, for BN, WN, WW, and PW, respectively. Correspondingly, direct heritability estimates were 0.17 ± 0.02, 0.13 ± 0.02, 0.17 ± 0.02, and 0.46 ± 0.04 for BN, WN, WW, and PW. Additive maternal effects accounted for trivial variation in PW. For BN, WN, and WW, respectively, maternal heritability estimates were 0.16 ± 0.02, 0.10 ± 0.02, and 0.07 ± 0.01. Uncorrelated maternal environmental effects accounted for little variation in any trait. Direct and maternal heterosis had considerable impact on growth traits, emphasizing the value of crossbreeding and the need to account for heterosis, in addition to breed effects, if crossbred lamb information is included in genetic evaluation.
Lay Summary Crossbreeding is common in commercial sheep enterprises. It allows breeds with different attributes to be combined to generate crossbred progeny tailored to production environments and customer preferences. Additionally, crossbreds often benefit from heterosis, performing at levels above the average of their parental breeds. Over two decades, body weights were collected at birth and at pre-weaning, weaning, and post-weaning ages on purebred and crossbred lambs from semi-prolific (Polypay), western range (Columbia, Rambouillet, Targhee), and terminal sire (Siremax, Suffolk, Texel) breeds at the U.S. Sheep Experiment Station. When combined, the value of direct heterosis—that due to a lamb being crossbred—and maternal heterosis—that due to the lamb’s dam being crossbred—increased birth (5%) and post-natal (up to 10%) weights in crossbred lambs. This highlights the value of crossbreeding to the U.S. sheep industry, especially in western range production systems. Genetic variation between and within breeds also was detected for the purebred parental breeds. Such heterotic and breed effects must be accounted for if crossbred performance is to be incorporated in genetic evaluation of purebreds. Therefore, these results provide the foundation for utilizing crossbred information in the evaluation and selection of purebred sheep in the United States
Study of the prolificacy in the segureña sheep. Preliminary results
The prolificacy of the Segureña sheep breed as a expresión of its potential numerical productivity is under study in the last years because this trait is considered as a selection criteria as the weight and daily gains. We have analizad more that 207850 parturitions. The results obatined here are expresed as a function of the number of parturition of each ewe and the month of parturition, showing mean values around 1.30 lambs by parturition, very interesting taking into account the conditions of exterme hardness in extensive systems where the breed is exploited.La prolificidad de la raza Segureña como expresión de la productividad numérica potencial que atesora la población está siendo estudiada en los últimos años pues este parámetro podrÃa considerarse como un posible criterio de selección al igual que las variables de pesos y crecimientos. Se analizan más de 207850 partos. Los resultados obtenidos se expresan en función del número de parto de la hembra y mes de parto, obteniéndose valores medios en torno a 1,30 corderos por parto cifra interesante teniendo en cuenta las condiciones de extrema dureza en extensivo en las que se produce esta raza
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