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971.
BS Andresen S Olpin BJ Poorthuis HR Scholte C Vianey-Saban R Wanders L Ijlst A Morris M Pourfarzam K Bartlett ER Baumgartner JB deKlerk LD Schroeder TJ Corydon H Lund V Winter P Bross L Bolund N Gregersen 《Canadian Metallurgical Quarterly》1999,64(2):479-494
Very-long-chain acyl-CoA dehydrogenase (VLCAD) catalyzes the initial rate-limiting step in mitochondrial fatty acid beta-oxidation. VLCAD deficiency is clinically heterogenous, with three major phenotypes: a severe childhood form, with early onset, high mortality, and high incidence of cardiomyopathy; a milder childhood form, with later onset, usually with hypoketotic hypoglycemia as the main presenting feature, low mortality, and rare cardiomyopathy; and an adult form, with isolated skeletal muscle involvement, rhabdomyolysis, and myoglobinuria, usually triggered by exercise or fasting. To examine whether these different phenotypes are due to differences in the VLCAD genotype, we investigated 58 different mutations in 55 unrelated patients representing all known clinical phenotypes and correlated the mutation type with the clinical phenotype. Our results show a clear relationship between the nature of the mutation and the severity of disease. Patients with the severe childhood phenotype have mutations that result in no residual enzyme activity, whereas patients with the milder childhood and adult phenotypes have mutations that may result in residual enzyme activity. This clear genotype-phenotype relationship is in sharp contrast to what has been observed in medium-chain acyl-CoA dehydrogenase deficiency, in which no correlation between genotype and phenotype can be established. 相似文献
972.
In this study a small diameter dynamic pressure probe was used to measure the flow characteristics and the annulus thickness in a circulating fluidized bed. The nonhomogeities of fluidization in the vertical and radial directions have been measured and the results are presented in a new way, as dynamic pressure against time. The diagrams reveal that the flow can, under certain conditions, exhibit significant reversals in the core areas. Particle size distribution in the vertical direction was also studied by using the quick-closing valve technique. The pilot scale riser was cylindrical and the particles were typical FCC catalyst. 相似文献
973.
Andrew Marete Goutam Sahana Sébastien Fritz Rachel Lefebvre Anne Barbat Mogens Sandø Lund Bernt Guldbrandtsen Didier Boichard 《Journal of dairy science》2018,101(7):6205-6219
Using a combination of data from the BovineSNP50 BeadChip SNP array (Illumina, San Diego, CA) and a EuroGenomics (Amsterdam, the Netherlands) custom single nucleotide polymorphism (SNP) chip with SNP pre-selected from whole genome sequence data, we carried out an association study of milking speed in 32,491 French Holstein dairy cows. Milking speed was measured by a score given by the farmer. Phenotypes were yield deviations as obtained from the French evaluation system. They were analyzed with a linear mixed model for association studies. We identified SNP on 22 chromosomes significantly associated with milking speed. As clinical mastitis and somatic cell score have an unfavorable genetic correlation with milking speed, we tested whether the most significant SNP on these 22 chromosomes associated with milking speed were also associated with clinical mastitis or somatic cell score. Nine hundred seventy-one genome-wide significant SNP were associated with milking speed. Of these, 86 were associated with clinical mastitis and 198 with somatic cell score. The most significant association signals for milking speed were observed on chromosomes 7, 8, 10, 14, and 18. The most significant signal was located on chromosome 14 (ZFAT gene). Eleven novel milking speed quantitative trait loci (QTL) were observed on chromosomes 7, 10, 11, 14, 18, 25, and 26. Twelve candidate SNP for milking speed mapped directly within genes. Of these, 10 were QTL lead SNP, which mapped within the genes HMHA1, POLR2E, GNB5, KLHL29, ZFAT, KCNB2, CEACAM18, CCL24, and LHPP. Limited pleiotropy was observed between milking speed QTL and clinical mastitis. 相似文献
974.
The Danish city Frederikshavn is aiming at becoming a 100% renewable energy city. The city has a number of energy resources including a potential for off-shore wind power, waste and low-temperature geothermal energy usable as heat source for heat pumps producing district heating. 相似文献
975.
Jorma Hoelsae Taneli Laamanen Mika Lastusaari Janne Niittykoski Pavel Novak 《中国稀土学报(英文版)》2009,27(4):550-554
The electronic structure of the strontium aluminate (SrAl2O4:Eu2+) materials was studied with a combined experimental and theoretical approach. The UV-VUV synchrotron radiation was applied in the experimental study while the electronic structure of the non-optimized and optimized crystal structure were investigated theoretically by using the density functional theory. The structure of the valence and conduction bands as well as the band gap energy of the material together with the position of the Eu2+ 4f7 8S7/2 ground state were calculated. The calculated band gap energy (6.4 eV) agreed well with the experimental value of 6.6 eV. The valence band consisted mainly of oxygen states whereas the bottom of the conduction band of strontium states. In agreement with the experimental results, the calculated 4f7 8S7/2 ground state of Eu2+ lies in the energy gap of the host. The position of the 4f7 ground state depended on the Coulomb repulsion strength. The position of the 4f7 ground state with respect to the valence and conduction bands was discussed using theoretical and experimental evidence available. 相似文献
976.
During a period of 9 months, 194 marinated and non-marinated poultry products were collected from retail shops in a defined area in Western Finland and tested for Campylobacter spp. using a conventional enrichment culture and Polymerase Chain Reaction (PCR) method. For marinated poultry products, the study involved modification of a commercial DNA isolation method. Using either a conventional culture or PCR method, a total of 25 (12.9%) of all investigated samples were Campylobacter positive. In marinated poultry products, Campylobacter was detected at a prevalence of 21.1% and 9.5% in turkey and chicken products, respectively. In August, there was a peak with 28.9% positive Campylobacter samples. Campylobacter inoculation tests were carried out to test the detection limit of both methods. The PCR method used is faster than microbiological analyses. However, enrichment of the samples is necessary due to the low occurrence of Campylobacter spp. in retail Finnish poultry products. 相似文献
977.
Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in triacylglycerol synthesis in the mammary gland, and the corresponding gene has emerged as a strong candidate for the variation in milk fat percentage. In this study, the allele frequencies and effects of the DGAT1 K232A variants in the Swedish dairy breeds Swedish Red and Swedish Holstein were investigated. A total of 239 cows, 143 of the Swedish Red breed and 96 of the Swedish Holstein breed, in the experimental herd at the Swedish University of Agricultural Sciences were genotyped for the DGAT1 polymorphism. The Swedish Red cows in the herd belonged to 1 of 2 selection lines with high or low milk fat percentage, respectively, but with similar high total milk energy production. The frequency of the K variant was found to be significantly greater in the high-fat line than in the low-fat line. The average frequency of the K variant in the 2 lines of the Swedish Red cows was 0.09 compared with 0.12 among the Swedish Holstein cows. Mixed model analysis was used to estimate the effect of the DGAT1 K232A polymorphism based on 16,866 test-day records for milk production traits. In accordance with previous studies, the most pronounced effects were found for fat and protein percentages and milk yield; and the K variant was associated with an increase in milk fat and protein percentages but less milk yield compared with the A variant. Less pronounced effects were found for yields of fat and protein for which the K variant was associated with greater fat yield but less protein yield. 相似文献
978.
Thomasen JR Guldbrandtsen B Sørensen P Thomsen B Lund MS 《Journal of dairy science》2008,91(5):2098-2105
The objectives of this study were 1) to detect quantitative trait loci (QTL) affecting direct and maternal calving traits at first calving in the Danish Holstein population, 2) to distinguish between pleiotropic and linked QTL for chromosome regions affecting more than one trait, and 3) to detect QTL affecting stillbirth and calving difficulties but not calf size that could be used in selection to improve calving performance. Progeny-tested sons (2,297) were genotyped for 356 microsatellites in 34 grandsire families on all 29 autosomes. A total of 27 significant QTL on 17 chromosomes were detected using a between-families linear regression model. For the direct calving traits, 4 QTL significantly affected calving difficulty, 5 QTL affected stillbirth, and 7 QTL affected calf size subjectively assessed by the farmer as a categorical trait. When the maternal components of the same traits were tested, there were significant effects of 3 QTL on calving difficulty, 6 QTL on stillbirth, and 2 QTL on calf size. The variance component mapping approach was used to estimate the relative posterior probability of linkage and pleiotropic models. The most probable model indicated a pleiotropic QTL on chromosome 12 and 25 and a linked QTL on chromosome 7 and 26. Chromosome 18 seemed to harbor a QTL with a pleiotropic effect on the direct calving traits and linked to maternal stillbirth. Markers on chromosomes 3, 4, 7, 10, 12, 18, 21, 24, 26, and 28 can be used to select new breeding candidates to produce daughters with more efficient calving performance. 相似文献
979.
High efficiency thermoelectric generators (TEG) can recover waste heat from both industrial and private sectors. Thus, the development and deployment of TEG may represent one of the main drives for technological change and fuel substitution. This paper will present an analysis of system efficiency related to the integration of TEG into thermal energy systems, especially Combined Heat and Power production (CHP). Representative implementations of installing TEG in CHP plants to utilize waste heat, wherein electricity can be generated in situ as a by-product, will be described to show advantageous configurations for combustion systems. The feasible deployment of TEG in various CHP plants will be examined in terms of heat source temperature range, influences on CHP power specification and thermal environment, as well as potential benefits. The overall conversion efficiency improvements and economic benefits, together with the environmental impact of this deployment, will then be estimated. By using the Danish thermal energy system as a paradigm, this paper will consider the TEG application to district heating systems and power plants through the EnergyPLAN model, which has been created to design suitable energy strategies for the integration of electricity production into the overall energy system. 相似文献
980.
A rapid method for sizing and placing of distributed electricity generation (DES) systems in an electric transmission network in respect to voltage has been developed and successfully validated. The new tool presented is in particularly useful for avoiding overvoltage situations, which are critical for the whole electricity system. The results show that DES placement closer to the transformer side is always more beneficial in terms of voltage than at the end of the line. Depending on the size of the DES unit, both up and downstream flow of power may occur. The method can be used for investigating a range of different placement and sizing configurations. 相似文献