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131.
Buitenhuis AJ Lund MS Thomasen JR Thomsen B Nielsen VH Bendixen C Guldbrandtsen B 《Journal of dairy science》2007,90(1):472-481
Lameness is an important factor for culling animals. Strong legs and feet improve herd life of dairy cows. Therefore, many countries include leg and feet conformation traits in their breeding programs, often as early predictors of longevity. However, few countries directly measure lameness related traits to include these in a breeding program. Lameness indices in 3 different lactations and 5 leg conformation traits (rear legs side view, rear legs rear view, hock quality, bone quality, and foot angle) were measured on granddaughters of 19 Danish Holstein grandsires with 33 to 105 sons. A genome scan was performed to detect quantitative trait loci (QTL) based on the 29 autosomes using microsatellite markers. Data were analyzed across and within families for QTL affecting lameness and leg conformation traits. A regression method and a variance component method were used for QTL detection. Two QTL each for lameness in the first [Bos taurus autosome (BTA); BTA5, BTA26] and second (BTA19, BTA22) lactations were detected. For the 5 different leg conformation traits, 7 chromosome-wise significant QTL were detected across families for rear legs side view, 5 for rear legs rear view, 4 for hock quality, 4 for bone quality, and 1 for foot angle. For those chromosomes where a QTL associated with 2 different traits was detected (BTA1, BTA11, BTA15, BTA26, and BTA27), a multitrait-1-QTL model and a multitrait-2-QTL model were performed to characterize these QTL as single QTL with pleiotropic effects or distinct QTL. 相似文献
132.
L. Zanini S. Dementjev W. Leung K. Thomsen M. Wohlmuther A. Class P. Agostini J.-C. David S. Leray L. Cachon P. Roubin N. Thiolliere 《Journal of Nuclear Materials》2011,415(3):367-377
The (MEGAWatt Pilot Experiment) MEGAPIE target was successfully irradiated in 2006 at the SINQ facility of the Paul Scherrer Institut. During the irradiation a series of measurements to monitor the operation of the target, the thermal hydraulics behavior and the neutronic and nuclear aspects, has been performed. In the post-test analysis phase of the project, the data were analyzed and important information relevant to accelerator-driven systems (ADS) was gained, in particular: (i) from the operation of the target several recommendations concern the simplification of the system and the improved reliability; (ii) data from the thermal hydraulic measurements have offered the opportunity to validate the codes used in the design phase; (iii) the neutronic analysis confirm the high performance of a liquid metal target and the importance of the delayed neutron measurements in an ADS target; (iv) the nuclear measurements of the gas released gave the opportunity to validate the codes used during the design phase and provided indications for the operation. From the results in these different domains recommendations to further development of ADS and heavy liquid metal targets are discussed. 相似文献
133.
不同脱毒方法对玉米秸秆水解液酒精发酵的影响 总被引:2,自引:1,他引:1
利用湿热预处理(195℃,15 min)后的玉米秸秆水解液,考察了3种不同脱毒方法(中和法、饱和生石灰法和Na2SO3法)对水解液中的抑制剂的去除效果,研究了树干毕赤酵母(Pichia stipitis 58376)对脱毒后的水解液酒精发酵情况.结果表明:玉米秸秆水解液经过3种方法脱毒处理后,醛类抑制荆(糠醛和5-羟甲... 相似文献
134.
De Vico L Iversen L Sørensen MH Brandbyge M Nygård J Martinez KL Jensen JH 《Nanoscale》2011,3(9):3635-3640
A single charge screening model of surface charge sensors in liquids (De Vico et al., Nanoscale, 2011, 3, 706-717) is extended to multiple charges to model the effect of the charge distributions of analyte proteins on FET sensor response. With this model we show that counter-intuitive signal changes (e.g. a positive signal change due to a net positive protein binding to a p-type conductor) can occur for certain combinations of charge distributions and Debye lengths. The new method is applied to interpret published experimental data on Streptavidin (Ishikawa et al., ACS Nano, 2009, 3, 3969-3976) and Nucleocapsid protein (Ishikawa et al., ACS Nano, 2009, 3, 1219-1224). 相似文献
135.
Here, we show that the Raman intensity of the G-mode in tip-enhanced Raman spectroscopy (TERS) is strongly dependent on the
height of the bundle. Moreover, using TERS we are able to position different single-walled carbon nanotubes along a bundle,
by correlating the observed radial breathing mode (RBM) with the AFM topography at the measuring point. The frequency of the
G- mode behaves differently in TERS as compared to far-field Raman. Using the RBM frequency, the diameters of the tubes were
calculated and a very good agreement with the G- -mode frequency was observed. 相似文献
136.
Vincenzo Liso Mads Pagh Nielsen Søren Knudsen Kær Henrik H. Mortensen 《International Journal of Hydrogen Energy》2014
Temperature changes in PEM fuel cell stacks are considerably higher during load variations and have a negative impact as they generate thermal stresses and stack degradation. Cell hydration is also of vital importance in fuel cells and it is strongly dependent on operating temperature. A combination of high temperature and reduced humidity increases the degradation rate. Stack thermal management and control are, thus, crucial issues in PEM fuel cell systems especially in automotive applications such as forklifts. 相似文献
137.
Werner Wagner Friedrich Gröschel Knud Thomsen Hajo Heyck 《Journal of Nuclear Materials》2008,377(1):12-16
The lead-bismuth liquid metal target MEGAPIE (MEGAwatt Pilot Experiment) was operated at the Swiss Spallation Neutron Source SINQ starting mid-August 2006, for a scheduled irradiation period until 21st of December 2006. The continuous (51 MHz) 590 MeV proton beam hitting the target reaches routinely an average current of ∼1300 μA, corresponding to a beam power 0.77 MW. This article illustrates the main features of the target and the ancillary systems specially needed for the liquid metal target operation. Further, the operational experiences made with this target during start-up and routine operation are summarized, besides the general performance highlighting new beam and target safety devices, and last but not least the neutronic efficiency in relation to the previously operated solid lead target. 相似文献
138.
Fox J. Marsack J. Kim J. Thomsen S. Rylander H.G. III Milner T.E. 《IEEE journal of selected topics in quantum electronics》2001,7(6):899-905
We report results of a study using optical coherence tomography (OCT) to create area maps of the retinal nerve fiber layer (RNFL) thickness. Low-resolution B scans (two-dimensional images) of the in vivo rhesus monkey retina have been recorded in the optic disk, peripapillary area, and macula. Three-dimensional (3-D) renderings of these areas have been created from OCT images and compared to corresponding data from histology. Results of our study indicate: (1) OCT may be utilized to measure the retinal nerve fiber layer thickness in vivo and (2) 3-D surface maps accurately depict the anatomy of the RNFL 相似文献
139.
Compas Bruce E.; Connor-Smith Jennifer K.; Saltzman Heidi; Thomsen Alexandria Harding; Wadsworth Martha E. 《Canadian Metallurgical Quarterly》2001,127(1):87
Progress and issues in the study of coping with stress during childhood and adolescence are reviewed. Definitions of coping are considered, and the relationship between coping and other aspects of responses to stress (e.g., temperament and stress reactivity) is described. Questionnaire, interview, and observation measures of child and adolescent coping are evaluated with regard to reliability and validity. Studies of the association of coping with symptoms of psychopathology and social and academic competence are reviewed. Initial progress has been made in the conceptualization and measurement of coping, and substantial evidence has accumulated on the association between coping and adjustment. Problems still remain in the conceptualization and measurement of coping in young people, however, and aspects of the development and correlates of coping remain to be identified. An agenda for future research on child–adolescent coping is outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
140.
Merrill Lex L.; Thomsen Cynthia J.; Sinclair Barbara B.; Gold Steven R.; Milner Joel S. 《Canadian Metallurgical Quarterly》2001,69(6):992
Female Navy recruits (N=5,226) completed surveys assessing history of childhood sexual abuse (CSA), childhood strategies for coping with CSA, childhood parental support, and current psychological adjustment. Both CSA and parental support independently predicted later adjustment. In analyses examining whether CSA victims' functioning was associated with CSA severity (indexed by 5 variables), parental support (indexed by 3 variables), and coping (constructive, self-destructive, and avoidant), the negative coping variables were the strongest predictors. A structural equation model revealed that the effect of abuse severity on later functioning was partially mediated by coping strategies. However, contrary to predictions, the model revealed that childhood parental support had little direct or indirect impact on adult adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献