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131.
Eunice N. Marete Jean-Christophe Jacquier Dolores O'Riordan 《Food research international (Ottawa, Ont.)》2013,50(2):593-596
The stability of parthenolide, the active ingredient in feverfew and a potential anti-inflammatory bioactive in beverages was evaluated at different pHs (2.9, 3.7, 4.6 and 6.0) during heat processing at 40–100 °C. The residual concentration of parthenolide was analysed by High Performance Liquid Chromatography and degradation kinetics determined using a nonisothermal method. Parthenolide degradation with thermal treatment followed pseudo-first order kinetics. The stability of parthenolide was significantly affected by pH and processing temperature. Feverfew infusions at near neutral pH levels exhibited good stability but a significant decrease in stability was observed at lower pHs. This model is likely to be a useful tool to predict the optimum pH and time-temperature profile required to retain parthenolide during heat processing. 相似文献
132.
133.
J.S. Pérez Guerrero L.C.G. Pimentel T.H. Skaggs M.Th. van Genuchten 《International Journal of Heat and Mass Transfer》2009,52(13-14):3297-3304
This paper presents a formal exact solution of the linear advection–diffusion transport equation with constant coefficients for both transient and steady-state regimes. A classical mathematical substitution transforms the original advection–diffusion equation into an exclusively diffusive equation. The new diffusive problem is solved analytically using the classic version of Generalized Integral Transform Technique (GITT), resulting in an explicit formal solution. The new solution is shown to converge faster than a hybrid analytical–numerical solution previously obtained by applying the GITT directly to the advection–diffusion transport equation. 相似文献
134.
New sulfur analogs of the sex pheromone of the female processionary mothThaumetopoea pityocampa have been found to be effective inhibitors of the natural pheromone activity both in EAG bioassays and field tests. The structures of these analogs have been derived from replacement of the oxygen atom(s) of the acetate group by sulfur (compounds 3-5) and the olefinic moiety of the enyne function by the isosteric SCH2 group (compounds 6 and 7). The synthesis and biological activity of 3-[(Z)-12-pentadecen-10-ynylthio]-1,1,1-trifluoropropan-2-one (8), a closely related structure to the pheromone is also described. 相似文献
135.
Qualls Sara Honn; Segal Daniel L.; Norman Suzanne; Niederehe George; Gallagher-Thompson Dolores 《Canadian Metallurgical Quarterly》2002,33(5):435
Rapid population growth among older adults means an increased need for psychologists prepared to provide mental health services to this population. A representative survey of 1,227 practitioner members of the American Psychological Association yielded information about current patterns of practice with older adults, sources of training in geropsychology, perceived need for continuing education (CE) in geropsychology, and preferred CE formats. Most respondents provided some services to older adults, but typically very little. The services provided are inadequate to meet projected demand. Most respondents lacked formal training in geropsychology and perceived themselves as needing additional training. CE workshops at the regional level and distance education were the most popular formats. These data serve as a call to the field to expand training opportunities at all levels of training, with an emphasis on the need for empirically based, broadly accessible CE offerings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Miguel Ángel Rincón‐Cervera María Dolores Suárez‐Medina José Luis Guil‐Guerrero 《European Journal of Lipid Science and Technology》2009,111(9):920-925
Fifteen roes from different marine fish species available in Spain were analyzed in order to determine their fatty acid (FA) composition, especially the eicosapentaenoic acid (20:5n‐3, EPA) and docosahexaenoic acid (22:6n‐3, DHA) contents. Roes from Atlantic bonito (Sarda sarda), European squid (Loligo vulgaris), cuttlefish (Sepia spp.), lumpfish (Cyclopterus lumpus), European hake (Merluccius merluccius), Atlantic salmon (Salmo salar) and gonads of male Atlantic mackerel (Scomber scombrus) reached EPA + DHA amounts higher than 30% of the total FA, and among them, roes from lumpfish, European hake and salmon provide different FA type ratios that could make them adequate as dietary sources of EPA and DHA. 相似文献
137.
138.
J. Miranda P. Partal F. Cordobes A. Guerrero 《Journal of the American Oil Chemists' Society》2002,79(2):183-190
The present work studies the rheological properties of avian egg yolks processed by spray-drying and by lipid-cholesterol
extraction with CO2 under near-critical conditions. The results have been compared with those obtained from native egg products in order to analyze
the effect of processing on the microstructure and rheological properties of egg yolks. The rheological study included linear
viscoelasticity measurements by means of dynamic oscillatory shear and creep tests, which provided information about the unperturbed
structure of the material, as well as steady-state flow measurements. The thermal denaturation of proteins, which was produced
during the spray-drying of egg yolk, was responsible for the dramatic change from fluid to gel-like behavior. The thermal
denaturation of proteins promotes the formation of a gel-like network, which may be attributed to exposure of internal hydrophobic
groups that favor protein aggregation. Lipid (and cholesterol) extraction from yolk increased the viscoelasticity functions
and flow properties due to the increased protein concentration. 相似文献
139.
During the last 15 years, reports, books, and published papers have demonstrated the positive health benefits of comprehensive health promotion and disease prevention interventions at the worksite. Although the progress made in worksite health promotion should not be understated, experts agree that it is time to step forward and address the new demands of the changing labor force. One area of intervention that needs to be more aggressively addressed is that of minority populations. Because work force projections show the high participation rate that Hispanics will have in the future labor force, the Hispanic population should be one of the targets of worksite health promotion. This paper reviews how employee health promotion programs have addressed Hispanic workers in the past and establishes directions for the future. 相似文献
140.
Opposing effects of quinacrine and chloroquine on the development of TA3 transplanted tumors in mice
Both quinacrine and chloroquine had been used as antimalarial agents. Furthermore, antineoplastic and antiviral effects have been described for quinacrine, while chloroquine has been described to induce viral replication and promote tumor growth. To search for differences in the growing rate of transplanted tumors, chloroquine or quinacrine were administered orally to AJ mice from 30 days previous to the inoculation of TA3 transplantable tumor cells, treatment being continued up to the end of the experiment. A control group, transplanted with tumor cells received tap drinking water. Marked differences between the three groups were found. Quinacrine had antitumoral effect, while chloroquine promoted a faster tumoral growth than controls. (p < 0.01). Results suggest caution in the use of chloroquine, because it might have a similar promoting effect on human neoplasia. 相似文献