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951.
ABSTRACT: The objective of this project was to treat fresh-cut apple slices with the ethylene inhibitor 1-methylcyclopropene (1-MCP) to retard ethylene-induced deterioration and senescence and to prolong the shelf life of such products. Intact Braeburn and Pacific Rose apples were treated at different times with 1-MCP, cut, and stored at 0 °C. Samples were analyzed initially and then weekly for ethylene, respiration, flesh firmness, tissue color, titratable acidity, and soluble solids content during 5 wk of storage. 1-MCP treatment was effective in reducing ethylene production, respiration, and loss of firmness and color of slices when applied to whole apples directly after harvest. Total sugar and acidity levels were not affected significantly. 相似文献
952.
Distribution of radiation exposure circumcranially for patients undergoing brain scanning with EMI computed tomographic equipment was measured using thermoluminescent dosimeters. The exposures are found to lie in the range of 1-5 R depending on position relative to tube motion. The maximum exposure of 5 R in CT scanning lies between the estimated exposure of 1.2 R for skull radiography and approximately 10 R for angiographic examination. Measured exposures are reported corresponding to locations of the patients' eyes, thyroid, chest and gonads, and at various locations in the vicinity of the unit. 相似文献
953.
Rollover protective structures (ROPS) are safety devices fitted to heavy vehicles to provide protection to the operator during an accidental rollover. At present, ROPS design standards require full-scale destructive testing, which can be expensive, time consuming, and unsuitable for small companies. More economical analytical methods would require an understanding on postyield behavior and energy absorption capacity of ROPS. With this in mind, this paper treats a bulldozer ROPS using experimental and analytical techniques to generate research information that will enable development of analytical design guidance and enhance safety. 相似文献
954.
Luiz Henrique Nunes Julio Cezar Estrella Charith Perera Stephan Reiff‐Marganiec Alexandre Cláudio Botazzo Delbem 《Software》2017,47(10):1325-1341
The growth of real‐world objects with embedded and globally networked sensors allows to consolidate the Internet of things paradigm and increase the number of applications in the domains of ubiquitous and context‐aware computing. The merging between cloud computing and Internet of things named cloud of things will be the key to handle thousands of sensors and their data. One of the main challenges in the cloud of things is context‐aware sensor search and selection. Typically, sensors require to be searched using two or more conflicting context properties. Most of the existing work uses some kind of multi‐criteria decision analysis to perform the sensor search and selection, but does not show any concern for the quality of the selection presented by these methods. In this paper, we analyse the behaviour of the SAW, TOPSIS and VIKOR multi‐objective decision methods and their quality of selection comparing them with the Pareto‐optimality solutions. The gathered results allow to analyse and compare these algorithms regarding their behaviour, the number of optimal solutions and redundancy. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
955.
An analysis of 16 cases of secondary hemorrhages in injuries of bones and soft tissues of the extremities is presented. The secondary hemorrhages occurred within the period from 16 hours to 27 days after the trauma. Angiographic study is a valuable adjunct for establishing the correct diagnosis. Arrosion of large arterial trunks was the adjunct for establishing the correct diagnosis. Arrosion of large arterial trunks was the basic cause of the secondary hemorrhage. In the prophylaxis of the latter a special importance is attached to a wide wound dissection in primary surgical treatment and to secure hemostasis, especially in the body portions having multilayer musculature. 相似文献
956.
By means of in vivo microscopy the influence of human, rat, and hamster purified salivary kallikreins upon the microvessels was studied in rat mesentery and hamster cheek pouch. Dilatation of arterioles, a decrease of the venule diameter, and an increase in the number of active capillaries was revealed. The species and organ peculiarities of these effects were described. The mesentery and the cheek pouch homogenates, albumin proteins, histamine and some amino acids were capable of activating the salivary kallikreins. 相似文献
957.
To define binding characteristics of drugs, levodopa melanin was prepared with the aid of mushroom tyrosinase. The binding of radiolabeled substances was studied with increasing concentrations of melanin in a fixed volume of potassium phosphate buffer (pH 7.4) at 37 degrees. The affinity and capacity of the drug binding were calculated according to Langmuir's adsorption isotherm. The affinity constant of various sympathomimetic amines such as (-)-amphetamine, (+)-amphetamine, (-)-ephedrine, (+/-)-octopamine, and (+)-norepinephrine ranged from 1.1 to 2.8 X 10(5) M-1. The binding capacity for the amines ranged from 1.4 to 3.2 X 10(-9) mole/mg. Although the capacity of (+/-)-cocaine for binding was similar to that of the amines, the affinity was slightly higher, 8.9 X 10(5) M-1. The binding of atropine to the synthetic melanin appeared to be a saturable process with the affinity and capacity values of 0.2 X 10(5) M-1 and 7.6 X 10(-9) mole/mg, respectively. Although the binding lacks stereoselectivity, the drugs vary in their capacity and affinity to bind with melanin. The observed differential pharmacological and toxicologic properties of drugs in the pigmented tissues may in part be related to their differential bi binding characteristics. 相似文献
958.
BP Grubb PN Temesy-Armos D Samoil DA Wolfe H Hahn L Elliott 《Canadian Metallurgical Quarterly》1993,25(1):24-28
The development and application of a highly sensitive double-target fluorescence in situ hybridization (FISH) method in combination with immunohistochemistry for detection of chromosome 1 abnormalities in interphase nuclei of neuroblastoma samples is reported. An alpha-satellite probe specific for chromosome 1 and a VNTR probe that hybridizes to chromosome band 1p36.3 were hybridized to GD2 prestained neuroblastoma cells in double-target FISH experiments. The ratio of intact to deleted chromosome 1 homologs in the neuroblastoma cells was assessed. To demonstrate the reliability of the method described, four selected samples derived from different neuroblastoma stages are presented. FISH results correlated well with data obtained by conventional cytogenetic procedures. The technique described allows sensitive detection of chromosome 1 abnormalities in interphase nuclei and enables partial cytogenetic analysis of nondividing cells with a defined immunological phenotype. 相似文献
959.
The performance of a 5 in. diameter diffusion pump (Edwards EO4) has been studied using a distillation cut of the perfluoropolyether fluid with an average mass of 3000 amu. A pumping speed for air of 700 l/s was measured which is similar to the speed obtained when the pump is charged with Silicone 704 fluid. A higher critical backing pressure was obtained, however, for the new fluid viz 1.2 torr compared with 0.8 torr for the conventional fluid. Fragmentation spectra of the vapour molecule obtained by direct injection into the ion source and from backstreaming fluid showed prominent peaks at mass to charge ratios 31 and 69 corresponding to the fragments CF and CF3. The similarity of the spectra obtained by the two methods suggests that the fragmentation takes place in the ion source and that the fluis is not degraded by use in the pump. An analysis of the pumping mechanism in vapour stream pumps is given. 相似文献