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71.
Frances Richards 《Journal of Failure Analysis and Prevention》2013,13(6):653-657
From aviation accidents to pipeline explosions, the National Transportation Safety Board is often called to determine probable cause and make safety recommendations, as they did in the aftermath of the 2010 San Bruno pipeline explosion. 相似文献
72.
J. Chen K. Chandrashekhara C. Mahimkar S. N. Lekakh V. L. Richards 《The International Journal of Advanced Manufacturing Technology》2012,62(9-12):1001-1011
Hot radial forging is used to reduce porosity and increase strength for large-diameter billets. The goal of this research is to study void closure behavior in the hot radial forging process. A nonlinear coupled finite element model is developed to investigate the deformation mechanism of internal void defects during the hot radial forging process. The model is formulated in a three-dimensional frame and a viscoplastic material model has been used to describe the material behavior subjected to large deformation and high temperature. A global–local technique is employed to obtain accurate solutions around the void region. The effects of void location, mandrel, die shape, and the reduction of the tube thickness on the final void reduction are systematically investigated. The predicted reductions for central longitudinal voids in hot upsetting and hot rolling processes are in good agreement with experimental findings. The simulation results provide a valuable procedure for the design of porosity reduction during the hot radial forging process. 相似文献
73.
The use of composite multiple feedback in a newly proposed virtual reality system enables the patient to perceive similar real-world performance in the virtual world. However, it might cause information overload, which makes the patient feel confused and distracted during training. The aim of this study is to investigate the effectiveness of having separate function-specific feedback pre-training prior to the final multiform feedback task. During the evaluating tests with thirty healthy subjects, it has been found that effective pre-training set could overcome the problem in the main task. Minor modifications on the pre-training set could overcome or aggravate the problem, which indicates the importance of choosing the correct pre-training parameters. 相似文献
74.
It is a matter of common knowledge that in laboratory hot-dip aluminizing, great difficulties are often encountered in preparing specimens that are free of surface oxides and other ubiquitous contaminants such as oils, grease and dust. Inadequate preparation of specimens will inevitably lead to the prevention of alloy layer growth during hot dipping and poor coatings following withdrawal. This paper describes a method for the production on a laboratory scale of hot-dipped type 1 aluminized sheet- steel specimens of commercial quality. 相似文献
75.
Nigel Allison Jackie Richards 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2014,89(9):1283-1287
Single use technology (SUT) is in widespread use throughout the biopharmaceutical industry where it is replacing traditional stainless steel plant particularly for the manufacture of small volume, high value products. The key drivers for SUT uptake include reduction of regulatory risk, lower capital and energy costs and increased facility flexibility. Disposable technology is now well established for cell culture, liquid handling and storage but its application to some downstream operations is proving more intractable. Single‐use chromatography resins are generally uneconomic at process scale and there are limitations on large‐scale tangential flow filtration capacities. The development of disposable sensor technology is lagging behind that of bioreactors and capacities for microbial culture are presently limited to 2000 litres. Concerns regarding compatibility of equipment from different suppliers and extractable and leachable testing are being addressed but continue to influence uptake of SUT by traditional manufacturers. Complete ‘plug and play’ disposable process trains, however, are becoming increasingly available and are being embraced by Contract Manufacturing Organisations (CMOs) with multiproduct facilities. © 2013 Society of Chemical Industry 相似文献
76.
Novel interactions of caffeic acid with different hemoglobins: Effects on discoloration and lipid oxidation in different washed muscles 总被引:1,自引:0,他引:1
Caffeic acid (CA) accelerated methemoglobin (Hb) formation at pH 5.8 and 25 °C. This was attributed to electron donation from CA to liganded O2 in Hb. CA inhibited hemin dissociation from metHb. Pig Hb remained mostly as oxyHb and did not promote lipid oxidation in washed cod muscle (WCM) nor washed turkey muscle (WTM) during iced storage at pH 5.8. Conversely, perch Hb rapidly was converted to metHb and readily promoted lipid oxidation based on lipid peroxide and hexanal formation. CA strongly inhibited perch Hb-mediated lipid oxidation during storage. Once metHb formation occurred in WCM, CA appeared to maintain the heme protein as metHb during the remainder of iced storage. CA may have become bound to perch Hb based on filtration analysis. CA facilitated the transfer of perch Hb (but not pig Hb) from the aqueous phase to the insoluble components of WCM. Collectively, these results suggest that CA inhibited Hb-mediated lipid oxidation by various mechanisms not related to inhibition of metHb formation. 相似文献
77.
78.
A. Richards T. Ginige A. Seneviratne T. Buczkowska M. Fry 《Concurrency and Computation》1994,6(4):357-373
It has been shown that protocol processing represents a severe bottle-neck for high speed computer networks. The disadvantages of currently proposed solutions are their incompatibility with existing standardised protocol implementations, their complexity and/or their inflexibility. One method of alleviating these limitation is to have an adaptable protocol stack, as proposed in the paper. Preliminary results are presented which show that significant gains in throughput can be achieved while creating a framework suitable for future applications. 相似文献
79.
Evelyn M. Templeton Moritz Lass Torsten Kleffmann Leigh J. Ellmers Suetonia C. Palmer Trent Davidson Nicola J. A. Scott John W. Pickering Christopher J. Charles Zoltan H. Endre Vicky A. Cameron A. Mark Richards Miriam T. Rademaker Anna P. Pilbrow 《International journal of molecular sciences》2022,23(2)
One-quarter of patients with acute decompensated heart failure (ADHF) experience acute kidney injury (AKI)—an abrupt reduction or loss of kidney function associated with increased long-term mortality. There is a critical need to identify early and real-time markers of AKI in ADHF; however, to date, no protein biomarkers have exhibited sufficient diagnostic or prognostic performance for widespread clinical uptake. We aimed to identify novel protein biomarkers of AKI associated with ADHF by quantifying changes in protein abundance in the kidneys that occur during ADHF development and recovery in an ovine model. Relative quantitative protein profiling was performed using sequential window acquisition of all theoretical fragment ion spectra–mass spectrometry (SWATH–MS) in kidney cortices from control sheep (n = 5), sheep with established rapid-pacing-induced ADHF (n = 8), and sheep after ~4 weeks recovery from ADHF (n = 7). Of the 790 proteins quantified, we identified 17 candidate kidney injury markers in ADHF, 1 potential kidney marker of ADHF recovery, and 2 potential markers of long-term renal impairment (differential abundance between groups of 1.2–2.6-fold, adjusted p < 0.05). Among these 20 candidate protein markers of kidney injury were 6 candidates supported by existing evidence and 14 novel candidates not previously implicated in AKI. Proteins of differential abundance were enriched in pro-inflammatory signalling pathways: glycoprotein VI (activated during ADHF development; adjusted p < 0.01) and acute phase response (repressed during recovery from ADHF; adjusted p < 0.01). New biomarkers for the early detection of AKI in ADHF may help us to evaluate effective treatment strategies to prevent mortality and improve outcomes for patients. 相似文献
80.
Amy Richards Chakra Wijesundera Phil Salisbury 《Journal of the American Oil Chemists' Society》2008,85(2):159-168
The effects of genotype and growing environment on the tocopherols and fatty acids (FA) of experimental Brassica juncea and B. napus breeding lines were investigated. For both species, with the exception of a few genotypes, the concentration ratio of γ-tocopherols
to α-tocopherol was practically constant. The genotype influenced the tocopherol concentration in B. napus, and to a lesser degree, B. juncea. The environment also had a similar effect, and a positive correlation existed between the daily maximum temperature and
the α-tocopherol concentration in B. napus. Genotype effects on the FA composition were significant for the conventional but not for Clearfield or triazine tolerant
traits of B. napus. The genotype had no effect on the FA of the B. juncea genotypes. In contrast, the growing environment had a significant influence on the FA composition of both species with apparent
influence from temperature and rainfall. For both species, the concentration of γ-tocopherol as well as total tocopherols
was inversely related to the 18:3 concentration, which could have resulted from opposite and independent effects of temperature
on the two variables. No relationship existed between the concentrations of tocopherol and the remaining unsaturated FA 18:1
and 18:2. The positional distribution of unsaturated FA within the oil triacylglycerol was a function of their total concentration. 相似文献