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61.
JF Richmond S Lu JC Santoro J Weng SL Hu DC Montefiori HL Robinson 《Canadian Metallurgical Quarterly》1998,72(11):9092-9100
DNA vaccination is an effective means of eliciting strong antibody responses to a number of viral antigens. However, DNA immunization alone has not generated persistent, high-titer antibody and neutralizing antibody responses to human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env). We have previously reported that DNA-primed anti-Env antibody responses can be augmented by boosting with Env-expressing recombinant vaccinia viruses. We report here that recombinant Env protein provides a more effective boost of DNA-initiated antibody responses. In rabbits primed with Env-expressing plasmids, protein boosting increased titer, persistence, neutralizing activity, and avidity of anti-Env responses. While titers increased rapidly after boosting, avidity and neutralizing activity matured more slowly over a 6-month period following protein boosting. DNA priming and protein immunization with HIV-1 HXB-2 Env elicited neutralizing antibody for T cell line-adapted, but not primary isolate, viruses. The most effective neutralizing antibody responses were observed after priming with plasmids which expressed noninfectious virus-like particles. In contrast to immunizations with HIV-1 Env, DNA immunizations with the influenza virus hemagglutinin glycoprotein did not require a protein boost to achieve high-titer antibody with good avidity and persistence. 相似文献
62.
63.
The Dufour's gland secretion ofXylocopa virginica texana possesses short-term repellency for conspecifics when applied to passion flowers. This secretion contains a number of straight-chain hydrocarbons. The two major components are the methyl esters of palmitic and myristic acid. A mixture of the two esters and two of the available hydrocarbons were as effective as the Dufour's gland extract in eliciting a response in females to the passion flower,Passiflora incarnata, to which the extract was applied.Approved as TA13387 by the Director, Texas Agricultural Experiment Station and conducted in cooperation with the USDA. Supported in part by NSF-DEB-76-03963. 相似文献
64.
N. A. Khan W. E. Tolberg D. H. Wheeler W. O. Lundberg 《Journal of the American Oil Chemists' Society》1954,31(11):460-466
- It has been confirmed that the principal products formed in the oxidation of methyl oleate by oxygen under a variety of conditions are predominantlytrans hydroperoxides. However no inversion of the double bond occurs in unoxidized oleate. Hence the conversion ofcis totrans double bonds and peroxide formation occur together in the same molecules.
- The autoxidation of methyl linoleate at low temperature yields predominantlycis,trans conjugated hydroperoxides. Autoxidation at 25°C., oxidation catalyzed by visible light, or ultraviolet light and copper soap catalyzed oxidation at temperatures appreciably above 0°C., lead to the formation primarily oftrans,trans conjugated hydroperoxides. The inversion of the second double bond in this case appears to be independent of the peroxide-forming reactions.
- The photochlorophyll oxidation of methyl linoleate leads to the formation of some unconjugated hydroperoxides, some of which containtrans double bonds.
- Under all of the conditions employed in the present investigation, the oxidation of methyl oleate and linoleate led primarily to the formation of monomeric peroxides which retained most of the unsaturation of the parent compound.
65.
Summary The rates of polymerization of alpha and beta eleostearates agree with second order kinetics, as would be expected for a bimolecular
Diels-Alder addition. The all-trans, beta isomer reacts faster than thecis, trans, trans alpha isomer, in agreement with knowncis, trans effects on diene activity.
The polymerization of normal linoleate follows an apparent first order reaction. It is suggested that conjugation is the slow
rate determining monomolecular reaction, as has been proposed for the non-conjugated linoleate isomers.
Paper No. 177, Journal Series, Research Laboratories, General Mills Inc. Presented at the 28th fall (Paul Bunyan) meeting
of the American Oil Chemists’' Society, Oct. 12, 1954, Minneapolis, Minn. 相似文献
66.
Jonathan Wheeler Ángel Galán-Martín Fernando D. Mele Gonzalo Guillén-Gosálbez 《American Institute of Chemical Engineers》2021,67(4):e17131
The design of sustainable supply chains, which recently emerged as an active area of research in process systems engineering, is vital to ensure sustainable development. Despite past and ongoing efforts, the available methods often overlook impacts beyond climate change or incorporate them via standard life cycle assessment metrics that are hard to interpret from an absolute sustainability viewpoint. We here address the design of biomass supply chains considering critical ecological limits of the Earth—planetary boundaries—which should never be surpassed by anthropogenic activities. Our method relies on a mixed-integer linear program that incorporates a planetary boundaries-based damage model to quantify absolute sustainability precisely. We apply this approach to the sugarcane-to-ethanol industry in Argentina, identifying the optimal combination of technologies and network layout that minimize the impact on these ecological boundaries. Our framework can find applications in a wide range of supply chain problems related to chemicals and fuels production, energy systems, and agriculture planning. 相似文献
67.
Edward J. Daniels Joseph A. CarpenterJr. Claudia Duranceau Michael Fisher Candace Wheeler Gerald Winslow 《JOM Journal of the Minerals, Metals and Materials Society》2004,56(8):28-32
Approximately 15 million cars and trucks reach the end of their useful life in the United States each year. More than 75%
of the materials from end-of-life vehicles are profitably recovered and recycled by the private sector; automotive materials
recycling is a success story. To achieve greater fuel efficiency and safety, today’s cars incorporate an increasing share
of innovative light-weight materials. While these materials greatly enhance efficiency during vehicle use, they can present
special challenges for recycling. These challenges will persist as automotive designs and the mix of materials used in vehicles
continue evolving to further improve safety and performance. To meet the challenges of automotive materials recycling, the
U.S. Department of Energy has recently expanded its collaborative research with industry in this area. This article discusses
this collaborative government/industry approach to sustainable end-of-life vehicle recycling.
For more information, contact Edward J. Daniels, Argonne National Laboratory, 9700 S. Cass Avenue, Building 362, Room C393,
Argonne, IL 60439-4815; (630) 252-5279; fax (630) 252-1342; e-mail edaniels@anl.gov. 相似文献
68.
The morbidity and mortality in short bowel syndrome are directly related to the length of the remaining small bowel and to the duration of total parenteral nutrition. We describe the successful salvage of an infant with extensive small bowel infarction for whom a new technique was used to preserve all viable mucosal surfaces. The infant, with gastroschisis, was found to have a tight volvulus of the extruded bowel and extensive small bowel ischemia at the time of delivery. Forty-eight hours after reduction of the volvulus and abdominal decompression, a second-look laparotomy was performed. Although only the terminal 13 cm of ileum was completely viable, 25% of the circumference of a further 23 cm of proximal jejunum/ileum was considered salvageable. After debridement of the dead tissue, the remaining gutter of jejunum was divided at its midpoint, and the two halves were anastomosed longitudinally to provide a "neojejunum" of 12 cm in length, which was anastomosed between the duodenum and terminal ileum. Full enteral feeding was tolerated from day 47. Although the neojejunum was excised on day 149, after becoming dilated and atonic, by that time the remaining small bowel had elongated to 30 cm. Because of the early institution of full enteral feeding, there were no long-term complications related to total parenteral nutrition. 相似文献
69.
OBJECTIVE: This study explored psychosocial and "environmental" correlates of childhood anxiety disorders. The study examined relationships among parental psychiatric symptomatology, perceived family environment, temperament, and self-competence in children with a DSM-III-R anxiety disorder. METHOD: A community sample of third through sixth graders was screened initially for symptoms of test anxiety. Those with high and low scores were administered the Anxiety Disorders Interview Schedule for Children. Three groups (childhood anxiety disorder, test-anxious only, and normal controls) were identified and compared on the psychosocial variables. RESULTS: Children with an anxiety disorder had greater impairment on the indices of perceived self-competence and temperamental flexibility than controls, with the test-anxious children showing intermediate, yet significant, levels of disturbance. There was a trend for children with an anxiety disorder to describe their families as less promoting of independence than the other groups. Finally, measures of parental psychiatric symptomatology revealed more obsessive-compulsive symptoms for the fathers of both the anxiety disorder and test-anxious children compared with controls. CONCLUSIONS: Results are consistent with previous findings suggesting the familial transmission of anxiety disorders and recent speculations regarding a relationship between behavioral inhibition, environmental control, and anxiety. Further research may isolate psychosocial and family environmental factors as instrumental treatment targets in the management of childhood anxiety disorders. 相似文献
70.
The classic hypoglossal transfer to the facial nerve is invariably followed by complications caused by tongue atrophy. In 1984, Terzis introduced the "baby-sitter" procedure which involved a formal cross-facial procedure, in addition to partial neurectomy of the hypoglossal nerve, and an end-to-side coaptation with the ipsilateral facial nerve. This reported study provides, for the first time, quantification of the number of hypoglossal motor fibers needed to successfully restore eye sphincter function, using an end-to-side coaptation with preservation of the tongue. Thirty adult Sprague-Dawley rats were divided into six groups: control, denervated, perineurial window, 20 percent partial neurectomy (PN), 40 percent PN, and 80 percent PN. The procedure involves interposing a nerve graft (saphenous) between the partially severed XII nerve and the upper zygomatic branch of the facial nerve. Evaluation of the behavioral data (blink reflex) revealed good-to-superb return of the blinking mechanism in the 40 percent group, without significant tongue atrophy. Electrophysiologic data in the 40 percent neurectomy group demonstrated superiority to the other groups. Quantitative axonal morphometry of the coaptation sites and graft, as well as motor end-plates of the orbicularis oculi muscle and tongue showed the 40 percent partial neurectomy group to be the optimal group. 相似文献