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71.
Yong Qin Koh Hassendrini N. Peiris Kanchan Vaswani Fatema B. Almughlliq Susanne Meier Chris R. Burke John R. Roche Charlotte B. Reed Buddhika J. Arachchige Sarah Reed Murray D. Mitchell 《Journal of dairy science》2018,101(7):6462-6473
The current study evaluated exosomes isolated from plasma of heifers bred to have high or low fertility through developing extreme diversity in fertility breeding values, however, key animal traits (e.g., body weight, milk production, and percentage of North American genetics) remained similar between the 2 groups. The exosomes were isolated by a combined ultracentrifugation and size exclusion chromatography approach and characterized by their size distribution (nanoparticle tracking analysis), morphology (transmission electron microscopy), and presence of exosomal markers (immunoblotting). In addition, a targeted mass spectrometry approach was used to confirm the presence of 2 exosomal markers, tumor susceptibility gene 101 and flotillin 1. The number of exosomes from plasma of high fertility heifers was greater compared with low fertility heifers. Interestingly, the exosomal proteomic profile, evaluated using mass spectrometry, identified 89 and 116 proteins in the high and low fertility heifers respectively, of which 4 and 31 were unique, respectively. These include proteins associated with specific biological processes and molecular functions of fertility. Most notably, the tetratricopeptide repeat protein 41-related, glycodelin, and kelch-like protein 8 were identified in plasma exosomes unique to the low fertility heifers. These proteins are suggested to play a role in reproduction; however, the role of these proteins in dairy cow reproduction remains to be elucidated. Their identification underscores the potential for proteins within exosomes to provide information on the fertility status and physiological condition of the cow. This may potentially lead to the development of prognostic tools and interventions to improving dairy cow fertility. 相似文献
72.
Objective: Evaluate the utility of the current 7-scale structure of the Life Situation Questionnaire—Revised (LSQ–R) using confirmatory factor analysis (CFA) and explore the factor structure of each set of items. Design: Adults (N = 1,543) with traumatic spinal cord injury (SCI) were administered the 20 satisfaction and 30 problems items from the LSQ–R. Results: CFA suggests that the existing 7-scale structure across the 50 items was within the acceptable range (root-mean-square error of approximation [RMSEA] = 0.078), although it fell just outside of this range for women. Factor analysis revealed 3 satisfaction factors and 6 problems factors. The overall fit of the problems items (RMSEA = 0.070) was superior to that of the satisfaction items (RMSEA = 0.80). RMSEA fell just outside of the acceptable range for Whites and men on the satisfaction scales. All scales had acceptable internal consistency. Conclusion: Results suggest the original scoring of the LSQ–R remains viable, although individual results should be reviewed for special population. Factor analysis of subsets of items allows satisfaction and problems items to be used independently, depending on the study purpose. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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许多人都将自拍视为一种自恋和自我陶醉的方式,而非真正的摄影,但我却乐此不疲,因为这带来了挑战自我和展现自己的机会,使我乐在其中. 相似文献
75.
Data were collected in 1998-2002 from wheat stored in commercial grain elevators in south-central Kansas. Bins at these elevators had concrete walls and were typically 6-9 m in diameter and 30-35 m tall. A vacuum-probe sampler was used to collect grain samples in the top 12 m of the wheat in each bin. The primary insect species found in the wheat samples were: Cryptolestes ferrugineus, Rhyzopertha dominica, and Tribolium castaneum. In the top 3.7 m of grain, R. dominica, C. ferrugineus, T. castaneum and Sitophilus oryzae made up 44, 36, 19 and 1% of the insects found in the samples, respectively. From 3.8 to 12.2 m, R. dominica, C. ferrugineus, T. castaneum and S. oryzae were present at 84, 8, 8, and 1%, respectively. The most prevalent species also changed over time. In June, the start of wheat harvesting and storage in Kansas, insect density was low in the bins. At this time, C. ferrugineus was the most common insect, and it was found mostly in the top grain sample (0-1.2 m). In September through November, C. ferrugineus and R. dominica were at similar densities; however, from February to March, R. dominica was more common.Generally, insect density was greatest at the top and decreased with grain depth. Very few insects were found in samples collected from greater than 12 m (most of the bins contained grain to depths of 24-36 m). Insect density for all species increased rapidly from June through October. During this period less than 20% of the bins had economically significant insect densities (>2 insects/kg). From October until February, the average insect density remained fairly constant but it was greatly reduced in April, May, and June. Bins that had insect densities >2 insects/kg tended to be located adjacent to other heavily infested bins. 相似文献
76.
Reed C.W. Cichanowskil S.W. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1994,1(5):904-922
This paper covers the basic phenomena involved in the aging of capacitors constructed using polymer films as the major dielectric material. A wide variety of aging phenomena can be identified, ranging from simple electrical, dielectric, thermal, radiation, chemical and physical aging, to aging originating from the specific construction of the capacitor. Some phenomena occur quickly, such as some morphological changes in the polymer, others occur progressively, and others occur later in the life of the capacitor. The polymers covered range from biaxially-oriented polypropylene, which is widely used in commercial utility and industrial capacitors, to polymers like polycarbonate, polysulfone, polyimide, and polyvinylidene fluoride, which are used in high-energy density, outer-space, high-temperature, or other special applications. The paper addresses two constructions of polymer film capacitor where the aging phenomena are significantly different due to the differences in construction: polymer/foil capacitors and metalized film capacitors. Metalized polymer film capacitors have the quality of clearing or self healing that is not present in film/foil capacitors. The discussion of aging in this paper is given from the perspective of these two designs 相似文献
77.
As part of comprehensive joint medical surveillance measures outlined by the Department of Defense, the US Army Center for Health Promotion and Preventive Medicine (USACHPPM) is beginning to assess environmental health threats to continental US military installations. A common theme in comprehensive joint medical surveillance, in support of Force Health Protection, is the identification and assessment of potential environmental health hazards, and the evaluation and documentation of actual exposures in both a continental US and outside a continental US setting. For the continental US assessments, the USACHPPM has utilized the US Environmental Protection Agency (EPA) database for risk management plans in accordance with Public Law 106-40, and the toxic release inventory database, in a state-of the art geographic information systems based program, termed the Consequence Assessment and Management Tool Set, or CATS, for assessing homeland industrial chemical hazards outside the military gates. As an example, the US EPA toxic release inventory and risk management plans databases are queried to determine the types and locations of industries surrounding a continental US military installation. Contaminants of concern are then ranked with respect to known toxicological and physical hazards, where they are then subject to applicable downwind hazard simulations using applicable meteorological and climatological data sets. The composite downwind hazard areas are mapped in relation to emergency response planning guidelines (ERPG), which were developed by the American Industrial Hygiene Association to assist emergency response personnel planning for catastrophic chemical releases. In addition, other geographic referenced data such as transportation routes, satellite imagery and population data are included in the operational, equipment, and morale risk assessment and management process. These techniques have been developed to assist military medical planners and operations personnel in determining the industrial hazards, vulnerability assessments and health risk assessments to continental United States military installations. These techniques and procedures support the Department of Defense Force Protection measures, which provides awareness of a terrorism threat, appropriate measures to prevent terrorist attacks and mitigate terrorism's effects in the event that preventive measures are ineffective. 相似文献
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79.
Plale B. Gannon D. Brotzge J. Droegemeier K. Kurose J. Mclaughlin D. Wilhelmson R. Graves S. Ramamurthy M. Clark R.D. Yalda S. Reed D.A. Joseph E. Chandrasekar V. 《Computer》2006,39(11):56-64
Two closely linked projects aim to dramatically improve storm forecasting speed and accuracy. CASA is creating a distributed, collaborative, adaptive sensor network of low-power, high-resolution radars that respond to user needs. LEAD offers dynamic workflow orchestration and data management in a Web services framework designed to support on-demand, real-time, dynamically adaptive systems 相似文献
80.
Estrogen withdrawal-induced human breast cancer tumour regression in nude mice is prevented by Bcl-2
MA Pratt S Krajewski M Menard M Krajewska H Macleod JC Reed 《Canadian Metallurgical Quarterly》1998,440(3):403-408
The purpose of this study was to assess the safety and efficacy of percutaneous transluminal cerebral balloon angioplasty (PTCBA) of extra- and intra-cranial arteries by investigating procedural outcome. Eighty haemodynamically significant extra- and intra-cranial lesions (% diameter stenosis > 70) in 74 clinically symptomatic patients were treated by elective and initial PTCBA between March 1991 and February 1996 and thereafter followed. Death, stroke, surgery, or repeated angioplasty of restenosis or new lesions were regarded as cerebral events after the initial PTCBA. The procedural and clinical success rates were 81 % (65 of 80) and 81 % (60 of 74), respectively. Progressively ischaemic symptoms disappeared completely after clinically successful dilatation. Angiographic restenosis rate at 3 months was 22 %(14 of 65). By life-table method, the death/stroke risk was 16 %, and any cerebral event risk was 49 % at 2 years following PTCBA, respectively. The most common of first cerebral events presented was repeated angioplasty of restenosis. In conclusion, PTCBA has great efficacy in decreasing recurrent neurological symptoms and produces a favourable short-term outcome, whereas restenosis limits long-term benefit. 相似文献