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41.
Cholesterol oxidation in lard containing two levels of added cholesterol was monitored using capillary gaschromatography.
Loss of cholesterol and formation of cholesterol oxidation products (COPs) were measured. Lard samples with 10 times (Test
I) and 2 times (Test II) the amount of cholesterol originally found in each batch of lard were heated at 180°C for 10 hr a
day for 240 and 160 hr, respectively. Cholesterol steadily decreased throughout the heating period in both tests. Cholesterol
loss followed a first-order reaction rate, with a rate constant (k) of −1.18×10−3 h−1 for Test I and −9.45×10−3 h−1 for Test II. The COPs accumulated during both heating tests. But the amount of COPs formed did not total the amount of cholesterol
lost. During heating, thermal degradation of cholesterol likely occurred, and those products were not detected. During cooling,
hydroperoxides formed, which further oxidized into the COPs that were detected. The 7-ketocholesterol and 5α,6α-epoxycholesterol
were the predominant COPs formed. The isomeric 7α-and 7β-hydroxycholesterols also accumulated in the heating tests. The 3β,5α,6β-cholestantriol
was found in very small amounts and the 25-hydroxycholesterol was not detected.
Presented in part at the 80th AOCS Annual Meeting, Cincinnati, OH, in May, 1989. 相似文献
42.
This treatability study evaluated the overall effectiveness of advanced oxidation processes (AOPs) to treat membrane concentrates containing the pesticides bromoxynil and trifluralin. The results of study indicate that high levels of pesticide degradation were achieved using ozone (O3) plus hydrogen peroxide (H2O2) for all concentrate matrices. However, the toxicity of the samples during the O3/H2O2 process was higher than that obtained during ultraviolet (UV) light combined with H2O2. Low levels of pesticide oxidation were observed in experiments using a mixture of pesticides during all treatment options. 相似文献
43.
Tana V. McDaniel Pamela A. Martin Glenn C. Barrett Kim Hughes Andrée D. Gendron Lenny Shirose Christine A. Bishop 《Journal of Great Lakes research》2009
Little is known of mudpuppy (Necturus maculosus) population structure and ecology; some populations in the Great Lakes are thought to be in decline. Mudpuppies are the obligate hosts for the mudpuppy mussel (Simpsonaias ambigua), a species that is endangered in Canada and in many Great Lakes states. We surveyed mudpuppies from the Sydenham River, the only known Canadian locality of the mudpuppy mussel, in order to generate information on relative density, deformity rates and population age/size structure and used this information to compare them to known mudpuppy populations from Great Lakes sites in the Detroit River, Lake St. Clair and Long Point in Lake Erie. Deformity rates were elevated at some sites in the Sydenham River. The relative density of mudpuppies in the Sydenham River was lower than that of other Great Lakes sites and their age was skewed towards younger individuals. Although at lower densities than at other Great Lakes sites, the mudpuppy population in the Sydenham River appears stable and is showing signs of recruitment which bodes well for the future of the mudpuppy mussel population of the river. 相似文献
44.
Erica Costantini Lisa Aielli Federica Serra Lorenzo De Dominicis Katia Falasca Pamela Di Giovanni Marcella Reale 《International journal of molecular sciences》2022,23(4)
Wound healing (WH) proceeds through four distinct phases: hemostasis, inflammation, proliferation, and remodeling. Impaired WH may be the consequence of the alteration of one of these phases and represents a significant health and economic burden to millions of individuals. Thus, new therapeutic strategies are the topics of intense research worldwide. Although radiofrequency electromagnetic field (RF-EMF) has many medical applications in rehabilitation, pain associated with musculoskeletal disorders, and degenerative joint disorders, its impact on WH is not fully understood. The process of WH begins just after injury and continues during the inflammatory and proliferative phases. A thorough understanding of the mechanisms by which RF-EMF can improve WH is required before it can be used as a non-invasive, inexpensive, and easily self-applicable therapeutic strategy. Thus, the aim of this study is to explore the therapeutic potential of different exposure setups of RF-EMF to drive faster healing, evaluating the keratinocytes migration, cytokines, and matrix metalloproteinases (MMPs) expression. The results showed that RF-EMF treatment promotes keratinocytes’ migration and regulates the expression of genes involved in healing, such as MMPs, tissue inhibitors of metalloproteinases, and pro/anti-inflammatory cytokines, to improve WH. 相似文献
45.
Ford Kentya H.; Diamond Pamela M.; Kelder Steven H.; Sterling Kymberle Landrum; McAlister Alfred L. 《Canadian Metallurgical Quarterly》2009,23(2):271
Attitudes toward smoking, self-efficacy to avoid smoking, and smoking intention, widely cited correlates of youth smoking prevention, are often measured in large-scale youth tobacco surveys. The psychometric properties of these scales have not been well studied among middle school youth. We examined the factorial, discriminate, and convergent validity of these scales among sixth to eighth graders from a convenience sample of 22 Texas middle schools (51.2% female; 51.21% White, 32.1% Hispanic, 16.9% African American, and 8.8% Other; 67.8% nonsmokers, 21.9% experimental smokers; 3.3% former smokers; and 7.6% current smokers). Confirmatory factor analysis and invariance testing suggest that smoking attitudes, self-efficacy, and intention have evidence of construct validity in this multiethnic sample, and the scales are appropriate to assess these constructs among middle school adolescents. Additional studies are needed to establish additional evidence of validity of these constructs in other middle school samples and other subgroups (e.g. current, experimental, and former smokers). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Multi-criteria location planning for public facilities in tsunami-prone coastal areas 总被引:3,自引:0,他引:3
We present a model for multi-objective decision analysis with respect to the location of public facilities as schools in areas
near to coasts, taking risks of inundation by tsunamis into account. A mathematical programming formulation with three objective
functions is given. The first objective function is a weighted mean of a minisum and a maximum coverage criterion. The second
objective function expresses risk by possible tsunami events; for quantifying this risk, a statistical model for tsunami occurrences
by Kaistrenko and Pinegina is applied. The third criterion represents costs. For the solution of the multi-objective optimization
problem, we propose a heuristic approach based on the NSGA-II algorithm and compare it with a decomposition technique where
the region under consideration is partitioned into smaller sub-regions, and the problem is solved for each separate subregion
either exactly or heuristically. Both approaches are tested on two real-life instances from southern Sri Lanka. 相似文献
47.
Blewitt Pamela; Rump Keiran M.; Shealy Stephanie E.; Cook Samantha A. 《Canadian Metallurgical Quarterly》2009,101(2):294
Shared book reading, and the conversation that accompanies it, can facilitate young children's vocabulary growth. To identify the features of extratextual questions that help 3-year-olds learn unfamiliar words during shared book reading, two experiments explored the impact of cognitive demand level, placement, and an approximation to scaffolding. Asking questions about target words improved children's comprehension and production of word–referent associations, and children with larger vocabularies learned more than children with smaller vocabularies. Neither the demand level nor placement of questions differentially affected word learning. However, an approximation to scaffolding, in which adults asked low demand questions when words first appeared and high demand questions later, did facilitate children's deeper understanding of word meanings as assessed with a definition task. These results are unique in experimentally demonstrating the value for word learning of shifting from less to more challenging input over time. Discussion focuses on why a scaffolding-like procedure improves children's acquisition of elaborated word meanings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
During the past decade, 3 major developments in psychotherapy have been converging: the establishment of evidence-based practices in psychology (EBPP); enormous growth in cognitive–behavior therapy and research (CBT); and increasing recognition of the impact of multicultural influences, as highlighted in the field of multicultural therapy (MCT). Cognitive–behavioral research has produced many empirically supported treatments used in the establishment of the scientific research base of EBPP, and MCT research has provided a wealth of qualitative information that balances this scientific emphasis with recognition of the importance of culturally competent clinical judgment, expertise, and experience. This article describes the advantages and potential limitations involved in the integration of CBT and multicultural considerations, with limitations reframed as opportunities to improve the relevance and effectiveness of psychotherapy. Ten suggestions are provided for integrating multicultural considerations into the clinical practice of cognitive–behavior therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
50.