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The effect of short-term storage on the protein, phosphorus and phenolic content as well as peroxidase and o-diphenolase activities of cut, harvested Jamaican yam (Dioscorea sp) tubers (D rotundata. D alata and D cayenensis) was studied. There was an initial increase in the total phenolic content up to the third week of storage followed by a gradual decrease to the sixth week. Phenolic content was found to be highest in D cayenensis followed by D rotundata and D alata. The activities of peroxidase (EC 1. 11. 1. 7) and o-diphenolase (EC 1. 10.3.1) increased steadily up to the third week of storage and thereafter decreased to the fifth week. The intensity and rapidity of browning in tubers when cut, correlated very closely with the tuber o-diphenolase and phenolic content levels while the onset of rotting correlated with the peroxidase activity levels in the species studied.  相似文献   
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The total syntheses of 9(Z),12(E)- and 9(E),12(Z)-octadecadienoic acids have been carried out. A useful intermediate in both syntheses, 8-bromo-octanoic acid, recently has become available from commercial sources. This compound has been used to expedite the preparation of these isomers. The remaining carbon atoms were derived from propargyl alcohol along with either 1-heptyne or acetylene and 1-bromopentane. Because the overall yield for each sequence was roughly 15% and there were no extraordinary reaction conditions in any of the synthetic steps, the compounds could be prepared readily in multiple gram quantities. The syntheses of the two compounds were supported by data from a variety of spectroscopic techniques.  相似文献   
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A genetic formulation for a hybrid finite element solution for three-dimensional electromagnetic scattering is given using the equivalent current approach. The major computational tasks involved in monostatic scattering calculations are analyzed and compared as a function of the method of implementing the near-field radiation condition, i.e. method of moments, model expansion, and body of revolution (BOR). A method utilizing a BOR formulation that addresses these computational issues is given. This BOR implementation utilizes Hermite cubic basis functions and a variable number of modes per basis function in order to achieve the greatest efficiency. The combined field integral equation formulation is used to eliminate nonphysical resonance of the mesh boundary. Examples are given showing the efficiency and accuracy of this BOR code by itself, and as part of this hybrid finite-element method.<>  相似文献   
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BACKGROUND: In an effort to intensify osteosarcoma therapy, systemic ifosfamide was added pre- and postoperatively to an already aggressive three-drug regimen. In a subgroup of patients, loco-regional treatment intensification was attempted by using the intraarterial route to give cisplatin. PATIENTS AND METHODS: Patients < or = 40 years at diagnosis of a localised, de novo high-grade central extremity osteosarcoma were eligible for inclusion into study COSS-86 if registered within three weeks from biopsy. Doxorubicin, high-dose methotrexate, and cisplatin were given to all patients. Patients who fulfilled one or more of three defined high-risk criteria received early systemic treatment intensification by adding ifosfamide as the fourth agent. Preoperatively, these high-risk patients received cisplatin either intraarterially or intravenously. RESULTS: 171 eligible patients were entered, of which 128 were stratified into the high-risk group. When all 171 were analysed by intention-to-treat, actuarial overall and event-free survival rates at ten years were 72% and 66%, respectively. No benefit of intraarterial cisplatin application was detected. Cumulative treatment toxicity was considerable. CONCLUSIONS: In a multicenter setting, intensive treatment of osteosarcoma according to protocol COSS-86 led to long-term disease-free survival for two thirds of patients. We saw no benefit of using the intraarterial route to administer cisplatin.  相似文献   
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Digitalization and the trend towards more short‐term and project‐oriented social engagement have had a direct impact on traditional crisis management. This societal change has supported the evolution of new types of volunteers who use low‐threshold potentials to organize and maintain support independently. Traditional institutions like the German Red Cross are challenged to deal with these rapid changes regarding their own organizational culture in relation to the new phenomenon of so‐called unaffiliated volunteers. This paper investigates how unaffiliated volunteers influence and change the organizational culture of German disaster management by analysing and reflecting organizational adaptation processes in the aftermath of the German floods in 2013, the storm events in the west of Germany in 2014 and the refugee relief mission in 2015–2016. Therefore, semi‐structured interviews with experts of the German Red Cross were held to analyse their reactions towards unaffiliated Volunteers during the Floods in 2013 and the refugee relief missions, and further focus group interviews were conducted to validate the extracted results. Findings suggest that among professionals and leading entities in the German Red Cross, a process of rethinking has emerged, recognizing the importance and necessity to open up organizational structures for the collaboration and coordination of unaffiliated volunteers.  相似文献   
8.
The formation of WN x /GaAs Schottky contacts using selective ion implantation of nitrogen into the sputtered tungsten film has been demonstrated. The contacts were characterized by Auger electron spectroscopy and current-voltage measurements. The composition of WN x films and the thermal stability of WN x /GaAs contacts were investigated. Good thermal stability of WN x /GaAs contacts compared with a W/GaAs contact was observed after capless rapid thermal annealing at 450, 800 and 950°C for 10 s.  相似文献   
9.
Thiosulfate in the form of sodium thiosulfate (STS) is a major oxidation product of hydrogen sulfide (H2S), an endogenous signaling molecule and the third member of the gasotransmitter family. STS is currently used in the clinical treatment of acute cyanide poisoning, cisplatin toxicities in cancer therapy, and calciphylaxis in dialysis patients. Burgeoning evidence show that STS has antioxidant and anti-inflammatory properties, making it a potential therapeutic candidate molecule that can target multiple molecular pathways in various diseases and drug-induced toxicities. This review discusses the biochemical and molecular pathways in the generation of STS from H2S, its clinical usefulness, and potential clinical applications, as well as the molecular mechanisms underlying these clinical applications and a future perspective in kidney transplantation.  相似文献   
10.
Glycol diesters and mixtures of mono- and diesters have been prepared from methyl esters of partially hydrogenated soybean oil fatty acids and diethylene, dipropylene, neopentyl and triethylene glycols. The catalyst used in these reactions was a mixture of calcium acetate/barium acetate (3∶1, w/w). The reactions were carried out under nitrogen with 0.5% catalyst at temperatures in the range of 190–275°C. Borated esters of mixed mono- and diesters were prepared with 0.33 equivalent of boric acid per 1.0 equivalent hydroxyl group on the ester. Refractive indices, viscosities, and flash and fire points were determined for diesters, mixed mono- and diesters, and mixed diesters and borated esters. The viscosities, flash points and fire points indicate that these esters can be used as a component of lubricating oils. Wear-prevention characteristics of mixed diesters and borated esters indicated that they can be used as antifriction additives in lubricating oils. Lecture presented at the joint meeting of the International Society for Fat Research and the American Oil Chemists' Society in Toronto, May 10, 1992.  相似文献   
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