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排序方式: 共有254条查询结果,搜索用时 15 毫秒
21.
G.R. Wiggans T.S. Sonstegard L.K. Matukumalli R.D. Schnabel F.S. Schenkel 《Journal of dairy science》2009,92(7):3431-3436
Nearly 57,000 single-nucleotide polymorphisms (SNP) genotyped with the Illumina BovineSNP50 BeadChip (Illumina Inc., San Diego, CA) were investigated to determine usefulness of the associated SNP for genomic prediction. Genotypes were obtained for 12,591 bulls and cows, and SNP were selected based on 5,503 bulls with genotypes from a larger set of SNP. The following SNP were deleted: 6,572 that were monomorphic, 3,213 with scoring problems (primarily because of poor definition of clusters and excess number of clusters), and 3,649 with a minor allele frequency of <2%. Number of SNP for each minor allele frequency class (≥2%) was fairly uniform (777 to 1,004). For 5 contiguous SNP assigned to chromosome 7, no bulls were heterozygous, which indicated that those SNP are actually on the nonpseudoautosomal portion of the X chromosome. Another 178 SNP that were not assigned to a chromosome but that had many fewer heterozygotes than expected were also assigned to the X chromosome. Existence of Hardy-Weinberg equilibrium was investigated by comparing observed with expected heterozygosity. For 11 SNP, the observed percentage of heterozygous individuals differed from the expected by >15%; therefore, those SNP were deleted. For 2,628 SNP, the genotype at another SNP was highly correlated (i.e., genotypes were identical for >99.5% of bulls), and those were deleted. After edits, 40,874 SNP remained. A parent-progeny conflict was declared when the genotypes were alternate homozygotes. Mean number of conflicts was 2.3 when pedigree was correct and 2,411 when it was incorrect. The sire was genotyped for >93% of animals. Maternal grandsire genotype was similarly checked; however, because alternate homozygotes could be valid, a conflict threshold of 16% was used to indicate a need for further investigation. Genotyping consistency was investigated for 21 bulls genotyped twice with differences primarily from SNP that were not scored in one of the genotypes. Concordance for readable SNP was extremely high (99.96-100%). Thousands of SNP that were polymorphic in Holsteins were monomorphic in Jerseys or Brown Swiss, which indicated that breed-specific SNP sets are required or that all breeds need to be considered in the SNP selection process. Genotypes from the Illumina BovineSNP50 BeadChip are of high accuracy and provide the basis for genomic evaluations in the United States and Canada. 相似文献
22.
Carolina Griebeler Gianluca Tondi Thomas Schnabel Carmen Iglesias Sergio Ruiz 《Holz als Roh- und Werkstoff》2018,76(5):1495-1504
A new method that consists of combining wood pre-grading by surface colour followed by the application of homogeneity thermal treatments is proposed to reduce the surface colour variability of the thermally modified blue gum wood. To identify the conditions of the homogeneity thermal treatment for two pre-graded groups with different initial surface colours (pinkish and yellowish), the effects of applying 25 different thermal treatment intensities to such groups were analysed. The effects of this method on mass loss and volumetric swelling were also analysed. Results show that an optical pre-grading of the wood samples and treatments under different conditions can reduce the colour variability of the blue gum wood samples, as well as the volumetric swelling. Mass loss was not homogenised after the treatment, but the difference of masses between the two groups was similar to their untreated state. The application of this new methodology may be of interest for the sawn timber industry to bring more uniform boards on the markets and to promote Eucalyptus globulus as a price-competitive and sustainable alternative timber. 相似文献
23.
24.
Kinetics of water adsorption in microporous aluminophosphate layers for regenerative heat exchangers
Hendrik van Heyden Gunther Munz Lena Schnabel Ferdinand Schmidt Svetlana Mintova Thomas Bein 《Applied Thermal Engineering》2009,29(8-9):1514-1522
The performance of thick aluminophosphate molecular sieve layers for heat exchanger applications is evaluated. The aluminophosphate AlPO-18 (AEI structure type code) molecular sieve sorbent is coated on aluminium supports prior the sorption measurements. Two AlPO-18 samples with different morphological appearance, i.e. nano-sized crystals with monomodal size distribution and micron-sized crystals of varying sizes, are used to prepare layers with thickness in the range of 80–750 μm. As a binder component, polyvinyl alcohol (PVOH) was utilized in order to prepare mechanically stable layers, which are mechanically stable over numerous measuring cycles. The sorption measurements are conducted under canonical conditions at 40 °C. The AlPO-18 layers showed decreased mass flows with increasing the thickness. Additionally, the layers comprising nanosized crystals showed higher equilibrium loadings and faster kinetics compared to films based on micron-sized crystals. Following the kinetic studies of pressure, temperature and heat flow, it can be concluded that the heat transport is the rate limiting mechanism for thick aluminophosphate layers. Importantly, the diffusion limitation plays a role only for relatively thin microporous aluminophosphate layers (<200 μm). Below this thickness complete heat transfer is achieved within 2 min which allows fast heat exchanger cycles. Thus, the application of microporous aluminophosphate layers for heat transformation and storage applications is considered possible. 相似文献
25.
This study analyzes the age profile of scientific employees and its relation to personnel costs and scientific productivity
within eight faculties at the University of Vienna. The age demography can overall be divided into two main categories: Category
one faculties represent an increased number of younger aged researchers (Catholic-, Protestant Theology, Law, Economics, Information
Sciences, and Medicine), category two faculties show an increased number of older aged researchers (Social Sciences, Humanities,
and Science). In addition, it can be demonstrated that the personnel costs for full professors are higher within four faculties
(Catholic-, Protestant Theology, Law, and Economics and Information Sciences). Inevitably, this leads to savings for habilitated
and non- habilitated researchers at these faculties. The faculty of Medicine represents a well-balanced use of personnel costs.
Three faculties (Social Sciences, Humanities, and Sciences) have to pay dramatically more for their older aged habilitated
and non-habilitated personnel. For the entire university and two faculties, Medicine and Humanities, a positive and significant
relationship between age and the average weekly teaching performance is shown. This study suggests that institutions with
a high percentage of older researchers, mainly in the categories of habilitated and non- habilitated personnel, must change
their policy to become more flexible and attractive for new talented young people. Due to the fact, that this cannot only
be realized through the introduction of new laws, each faculty must establish a scientific plan combined with reorganizations
of the personnel structure and personnel costs.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
26.
Conflicts over conservation are often regarded as dichotomies of diametrical opposites. When national parks are established in Norway, two stereotypes can be sketched: (1) the ecocentric position valuing 'pure, authentic nature', relying on the national government as the only acceptable decision and management level; and (2) a more anthropocentric position valuing cultural landscape elements and certain traditional and future uses of the area, favouring local management. A conflict over restoring a firing range to a state of 'authentic nature' for future designation as a national park is examined. The case has raised comprehensive local debate. It is asked whether the relevant actors should be seen as situated in the stereotypes, or whether a more complex three-dimensional picture would provide a better interpretation. 相似文献
27.
Murphy K van Ginneken B Reinhardt JM Kabus S Ding K Deng X Cao K Du K Christensen GE Garcia V Vercauteren T Ayache N Commowick O Malandain G Glocker B Paragios N Navab N Gorbunova V Sporring J de Bruijne M Han X Heinrich MP Schnabel JA Jenkinson M Lorenz C Modat M McClelland JR Ourselin S Muenzing SE Viergever MA De Nigris D Collins DL Arbel T Peroni M Li R Sharp GC Schmidt-Richberg A Ehrhardt J Werner R Smeets D Loeckx D Song G Tustison N Avants B Gee JC Staring M Klein S Stoel BC Urschler M 《IEEE transactions on medical imaging》2011,30(11):1901-1920
EMPIRE10 (Evaluation of Methods for Pulmonary Image REgistration 2010) is a public platform for fair and meaningful comparison of registration algorithms which are applied to a database of intrapatient thoracic CT image pairs. Evaluation of nonrigid registration techniques is a nontrivial task. This is compounded by the fact that researchers typically test only on their own data, which varies widely. For this reason, reliable assessment and comparison of different registration algorithms has been virtually impossible in the past. In this work we present the results of the launch phase of EMPIRE10, which comprised the comprehensive evaluation and comparison of 20 individual algorithms from leading academic and industrial research groups. All algorithms are applied to the same set of 30 thoracic CT pairs. Algorithm settings and parameters are chosen by researchers expert in the configuration of their own method and the evaluation is independent, using the same criteria for all participants. All results are published on the EMPIRE10 website (http://empire10.isi.uu.nl). The challenge remains ongoing and open to new participants. Full results from 24 algorithms have been published at the time of writing. This paper details the organization of the challenge, the data and evaluation methods and the outcome of the initial launch with 20 algorithms. The gain in knowledge and future work are discussed. 相似文献
28.
Christoph Schnabel 《Datenschutz und Datensicherheit - DuD》2007,31(6):426-430
Im Aufsehen erregenden „Mikado“-Fall haben die Ermittlungsbeh?rden Banken dazu bewegt, 22 Millionen deutsche Kreditkartenkonten
zu überprüfen. Dabei wurden 322 Personen ermittelt und deren Wohnungen und Gesch?ftsr?ume daraufhin durchsucht, ob sie kinderpornographische
Bilder besa?en. Der Beitrag geht der Frage nach, ob es sich dabei um eine zul?ssige Fahndungsmethode handelte, indem er die
Ermittlungen aus datenschutzrechtlicher und strafprozessualer Sicht untersucht. 相似文献
29.
M B?hm O Zolk M Flesch F Schiffer P Schnabel JP Stasch A Knorr 《Canadian Metallurgical Quarterly》1998,31(3):747-754
PURPOSE: To present 10 years experience with direct fluoroscopically guided percutaneous jejunostomy. MATERIALS AND METHODS: Percutaneous jejunostomy was performed in 62 patients, most of whom had undergone major abdominal surgery. A new or replacement jejunostomy was created for alimentation in 20 and 21 patients, respectively. Jejunostomy was performed for interventional procedures of the bile ducts or intestine in 13 patients and for retrograde gastroesophageal drainage in eight. The distended jejunum was accessed with a 21-gauge needle, immobilized with a gastric anchor, and catheterized with a 10-14-F locking loop drain. RESULTS: The technical success rate was 19 of 20 (95%) for new feeding jejunostomy and 17 of 21 (81%) for replacement feeding jejunostomy. Jejunostomy facilitated drainage, dilation, stone extraction, and recanalization in the bile ducts or intestine in all 13 patients. Retrograde jejunoesophagogastrostomy suction effectively replaced painful nasogastric suction in all eight patients. Two patients who underwent replacement jejunostomy required laparotomy for possible leakage; there was no important procedure-related morbidity and no procedure-related mortality. CONCLUSION: The technical success and complication rates of feeding percutaneous jejunostomy compare favorably with those of surgery or endoscopy. Percutaneous jejunostomy is a useful and underused approach to managing bowel and biliary obstruction. 相似文献
30.