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41.
S.C. Ring D.A. Graham R.G. Sayers N. Byrne M.M. Kelleher M.L. Doherty D.P. Berry 《Journal of dairy science》2018,101(7):6190-6204
Bovine herpesvirus-1 (BoHV-1) is a viral pathogen of global significance that is known to instigate several diseases in cattle, the most notable of which include infectious bovine rhinotracheitis and bovine respiratory disease. The genetic variability in the humoral immune response to BoHV-1 has, to our knowledge, not ever been quantified. Therefore, the objectives of the present study were to estimate the genetic parameters for the humoral immune response to BoHV-1 in Irish female dairy cattle, as well as to investigate the genetic relationship between the humoral immune response to BoHV-1 with milk production performance, fertility performance, and animal mortality. Information on antibody response to BoHV-1 was available to the present study from 2 BoHV-1 sero-prevalence research studies conducted between the years 2010 to 2015, inclusive; after edits, BoHV-1 antibody test results were available on a total of 7,501 female cattle from 58 dairy herds. National records of milk production (i.e., 305-d milk yield, fat yield, protein yield, and somatic cell score; n = 1,211,905 milk-recorded cows), fertility performance (i.e., calving performance, pregnancy diagnosis, and insemination data; n = 2,365,657 cows) together with animal mortality data (i.e., birth, farm movement, death, slaughter, and export events; n = 12,853,257 animals) were also available. Animal linear mixed models were used to quantify variance components for BoHV-1 as well as to estimate genetic correlations among traits. The estimated genetic parameters for the humoral immune response to BoHV-1 in the present study (i.e., heritability range: 0.09 to 0.16) were similar to estimates previously reported for clinical signs of bovine respiratory disease in dairy and beef cattle (i.e., heritability range: 0.05 to 0.11). Results from the present study suggest that breeding for resistance to BoHV-1 infection could reduce the incidence of respiratory disease in cattle while having little or no effect on genetic selection for milk yield or milk constituents (i.e., genetic correlations ranged from ?0.13 to 0.17). Moreover, even though standard errors were large, results also suggest that breeding for resistance to BoHV-1 infection may indirectly improve fertility performance while also reducing the incidence of mortality in older animals (i.e., animals >182 d of age). Results can be used to inform breeding programs of potential genetic gains achievable for resistance to BoHV-1 infection in cattle. 相似文献
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Fructose 1,6-bisphosphate (FBP) protects astrocytes from hypoxic injury in vitro. To determine whether FBP and citrate (inhibitors of phosphofructokinase) ameliorate hypoxia-induced injury to neurons and, if they do, whether the protective effects are a direct result of their actions on neurons or a consequence of their actions on astrocytes, we added FBP or citrate to the media of normoxic and hypoxic 'pure', mixed and co-culture systems. FBP (3.5 mM) and citrate (10 microM-2 mM) decreased release of LDH from astrocytes following 24 h of hypoxia. Eight hours of hypoxia killed pure neuronal cultures and neither FBP nor citrate prevented this death. However, in mixed and co-culture systems, FBP and citrate increased neuronal viability (as determined by the ratio of live-to-total cells), even after 47 h of hypoxia. In co-culture, following 24 h of hypoxia, both FBP and citrate reduced neuronal release of LDH and neuronal death. Fluorocitrate, a suicidal-inhibitor of aconitase, also protected astrocytes, but not neurons, from hypoxia in 'pure' culture, presumably by increasing intracellular citrate concentrations through inhibition of the catalysis of citrate to isocitrate We conclude that FBP and citrate attenuate hypoxic neuronal injury through their effects on astrocytes. 相似文献
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Sheldon D.J. Gruenschlaeger C.W. Kammerdiner L. Henis N.B. Kelleher P. Hayden J.D. 《Semiconductor Manufacturing, IEEE Transactions on》1988,1(4):140-146
The application of a novel planarization process using a sacrificial fill layer of photoresist is presented. The process is shown to solve the planarization problems encountered in both intermetal dielectric for a 1.2 μm 256 K SRAM technology and trench isolation for a0.8-μm 1M SRAM technology. The process is a simple extension of the standard dielectric etch-back scheme. A discussion of how to precisely quantify circuit planarization using well-known techniques is also presented. This information can then be adapted for statistical quality control purposes 相似文献
45.
A retrospective follow-up study was performed on 40 patients, in which tuberculous spondylitis was treated conservatively between 1969 and 1985 with orthotic supports for an average of 16 months (range, 10-30 months) and with anti-tuberculous agents. All had persistent back pain, but none had neurological deficits. The mean follow-up period was 17 years (range, 10-26 years). Diagnosis was confirmed histopathologically. The spinal segments involved ranged from T5 to L5. The kyphotic angle was calculated according to Cobb. At final follow-up, 22 patients were pain free, 11 had occasional pain, 6 complained of pain in the morning, and 1 had chronic pain and needed frequent analgesics. Solid bony union was found in 75% of patients. The kyphotic deformity occurred in the thoracic spine with a mean angle of 20 degrees (range, 13-28 degrees) and in the lumbar spine with a mean angle 12 degrees (range, 5-26 degrees). The long-term follow-up of conservative treatment showed only slightly increased kyphosis. Conservative treatment is an alternative to surgical intervention in cases with kyphosis < 35 degrees. 相似文献
46.
Brian Conroy Yéli Traoré Sanjooram Paddea Joe Kelleher 《Materials Science & Technology》2017,33(10):1231-1251
ASTM F75 femoral knee implant components distort during manufacture due to residual stress re-distribution or inducement. X-ray diffraction, neutron diffraction, centre-hole drilling and the contour method residual stress determination techniques were applied to as-cast and/or shot-blasted components. The centre-hole drilling and contour methods can only be considered qualitative as a result of uncertainty associated with the elastic anisotropy of gauge volumes. Additionally, neutron diffraction experimentation returned unfeasible results. However, it was qualitatively identified that a shot-blasting shell-removal process has the ability to significantly alter the bulk residual stress state of the implants and induce a stress state which would cause distortion by re-distribution following material removal during manufacturing processes. 相似文献
47.
DSC analysis of acrylonitrile-butadiene-styrene (ABS) samples either weathered outdoors for up to 10 years or aged at 71°C has shown that these plastics deteriorate most readily through the polybutadiene (BD) component. Oxidation of the BD in ABS leads to an increasing and broadening Tgas well as a decrease in ΔCp at Tg. The latter quantity can be used to quantitatively assay the amount of unoxidized rubber in a photo- or thermal-oxidized sample. The loss of impact strength of these resins with chemical aging can be correlated with the oxidation of the polybutadiene phase. Studies of rubber content as a function of sample thickness have revealed that an embrittled layer containing oxidized BD develops at the surface of an aged, 100 mil. ABS plaque (natural) and grows to a thickness of about 10 mils after 3 years exposure to sunlight. ABS containing carbon black is effectively screened from this photo induced degradation and consequently has much better retention of its initial impact strength values. In addition, carbon black was observed to retard thermal oxidation in some ABS samples. Lastly, it appears possible to do accelerated aging studies at elevated temperatures to evaluate the relative stabilities of various ABS formulations. 相似文献
48.
Inside Cover: Improving Cell‐Free Protein Synthesis through Genome Engineering of Escherichia coli Lacking Release Factor 1 (ChemBioChem 5/2015) 下载免费PDF全文
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The extension of quantitation methods for small peptides to ions above 5 kDa, and eventually to global quantitative proteomics of intact proteins, will require extensive refinement of current analytical approaches. Here we evaluate postgrowth Cys-labeling and 14N/15N metabolic labeling strategies for determination of relative protein expression levels and their posttranslational modifications using top-down mass spectrometry (MS). We show that intact proteins that are differentially alkylated with acrylamide (+71 Da) versus iodoacetamide (+57 Da) have substantial chromatographic shifts during reversed-phase liquid chromatography separation (particularly in peak tails), indicating a requirement for stable isotopes in alkylation tags for top-down MS. In the 14N/15N metabolic labeling strategy, we achieve 98% 15N incorporation in yeast grown 10 generations under aerobic conditions and determine 50 expression ratios using Fourier transform ion cyclotron resonance MS in comparing these cells to anaerobically grown control (14N) cells. We devise quantitative methods for top-down analyses, including a correction factor for accurate protein ratio determination based upon the signal-to-noise ratio. Using a database of 200 yeast protein forms identified previously by top-down MS, we verify the intact mass tag concept for protein identification without tandem MS. Overall, we find that top-down MS promises work flows capable of large-scale proteome profiling using stable isotope labeling and the determination of >5 protein ratios per spectrum. 相似文献