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41.
Richard J Bloomer Robert E Canale Megan M Blankenship Kelsey H Fisher-Wellman 《Nutrition journal》2010,9(1):49
Background
The purpose of this investigation was to determine the effects of a dietary supplement (Ambrotose AO®) on resting and exercise-induced blood antioxidant capacity and oxidative stress in exercise-trained and untrained men and women.Methods
25 individuals (7 trained and 5 untrained men; 7 trained and 6 untrained women) received Ambrotose AO® (4 capsules per day = 2 grams per day) or a placebo for 3 weeks in a random order, double blind cross-over design (with a 3 week washout period). Blood samples were collected at rest, and at 0 and 30 minutes following a graded exercise treadmill test (GXT) performed to exhaustion, both before and after each 3 week supplementation period. Samples were analyzed for Trolox Equivalent Antioxidant Capacity (TEAC), Oxygen Radical Absorbance Capacity (ORAC), malondialdehyde (MDA), hydrogen peroxide (H2O2), and nitrate/nitrite (NOx). Quality of life was assessed using the SF-12 form and exercise time to exhaustion was recorded. Resting blood samples were analyzed for complete blood count (CBC), metabolic panel, and lipid panel before and after each 3 week supplementation period. Dietary intake during the week before each exercise test was recorded.Results
No condition effects were noted for SF-12 data, for GXT time to exhaustion, or for any variable within the CBC, metabolic panel, or lipid panel (p > 0.05). Treatment with Ambrotose AO® resulted in an increase in resting levels of TEAC (p = 0.02) and ORAC (p < 0.0001). No significant change was noted in resting levels of MDA, H2O2, or NOx (p > 0.05). Exercise resulted in an acute increase in TEAC, MDA, and H2O2 (p < 0.05), all which were higher at 0 minutes post exercise compared to pre exercise (p < 0.05). No condition effects were noted for exercise related data (p > 0.05), with the exception of ORAC (p = 0.0005) which was greater at 30 minutes post exercise for Ambrotose AO® compared to placebo.Conclusion
Ambrotose AO® at a daily dosage of 4 capsules per day increases resting blood antioxidant capacity and may enhance post exercise antioxidant capacity. However, no statistically detected difference is observed in resting or exercise-induced oxidative stress biomarkers, in quality of life, or in GXT time to exhaustion.42.
Reverse osmosis (RO) treatment has been found to be effective for a wide range of organics but generally small, polar, uncharged molecules such as N-nitrosodimethylamine (NDMA) can be poorly rejected. The rejection of seven N-nitrosoalkylamines with molecular masses in the range of 78-158Da, including NDMA, N-nitrosodiethylamine (NDEA), N-nitrosomethylethylamine (NMEA), N-nitrosodipropylamine (NDPA), N-nitrosodibutylamine (NDBA), N-nitrosopyrrolidine (NPyr), N-nitrosopiperidine (NPip) by three commercial brackish-water reverse osmosis membranes was studied in flat-sheet cells under cross-flow conditions. The membranes used were ESPA3 (Hydranautics), LFC3 (Hydranautics) and BW-30 (Dow/Filmtec), commonly used in water reuse applications. The effects of varying ionic strength and pH, dip-coating membranes with PEBAX 1657, a hydrophilic polymer, and artificial fouling with alginate on nitrosamine rejection were quantified. Rejection in deionized (DI) water increased with molecular mass from 56 to 70% for NDMA, to 80-91% for NMEA, 89-97% for NPyr, 92-98% for NDEA, and to beyond the detection limits for NPip, NDPA and NDBA. For the nitrosamines with quantifiable transmission, linear correlations (r(2)>0.97) were found between the number of methyl groups and the log(transmission), with factor 0.35 to 0.55 decreases in transmission per added methyl group. A PEBAX coating lowered the ESPA3 rejection of NDMA by 11% but increased the LFC3 and BW30 rejection by 6% and 15%, respectively. Artificially fouling ESPA3 membrane coupons with 170g/m(2) alginate decreased the rejection of NDMA by 18%. A feed concentration of 100mM NaCl decreased rejection of NDMA by 15% and acidifying the DI water feed to pH=3 decreased the rejection by 5%, whereas increasing the pH to 10 did not have a significant (p<0.05) effect. 相似文献
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44.
The ultimate coke yield was determined for agglomerates of Athabasca vacuum residue and coke particles by heating on Curie‐point alloy strips in an induction furnace at 503 and 530°C until all toluene‐soluble material was converted. Coke yield results from agglomerates were compared to the coke yield results from reacting thin films of vacuum residue. The average coke yield from the agglomerates was 23%, while the coke yield from thin films of 20 µm thickness was 11%, which supports the role of mass transfer in coke formation reactions. The ultimate coke yield was insensitive to vacuum residue concentration, agglomerate size, and reaction temperature. The temperature profile within agglomerates was measured by implanting a thermocouple, and a simple heat transfer model was used to describe the temperature variation with time. The effective thermal diffusivity of the agglomerates was 0.20 × 10?6 m2/s. Control experiments on reaction in thin liquid films confirmed that heating rates in the range of 14.8–148 K/s had no effect on the ultimate yield of coke yield. 相似文献
45.
Dr. Marina Tanasova Matthew Plutschack Megan E. Muroski Prof. Shana J. Sturla Prof. Geoffrey F. Strouse Prof. D. Tyler McQuade 《Chembiochem : a European journal of chemical biology》2013,14(10):1263-1270
Recent publications suggest that high dietary fructose might play a significant role in cancer metabolism and can exacerbate a number of aspects of metabolic syndrome. Addressing the role that fructose plays in human health is a controversial question and requires a detailed understanding of many factors including the mechanism of fructose transport into healthy and diseased cells. Fructose transport into cells is thought to be largely mediated by the passive hexose transporters Glut2 and Glut5. To date, no probes that can be selectively transported by one of these enzymes but not by the other have been identified. The data presented here indicate that, in MCF‐7 cells, a 1‐amino‐2,5‐anhydro‐D ‐mannitol‐based fluorescent NBDM probe is transported twice as efficiently as fructose and that this takes place with the aid of Glut5. Its Glut5 specificity and differential uptake in cancer cells and in normal cells suggest this NBDM probe as a potentially useful tool for cross‐cell‐line correlation of Glut5 transport activity. 相似文献
46.
Piper Megan E.; Piasecki Thomas M.; Federman E. Belle; Bolt Daniel M.; Smith Stevens S.; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2004,72(2):139
The dependence construct fills an important explanatory role in motivational accounts of smoking and relapse. Frequently used measures of dependence are either atheoretical or grounded in a unidimensional model of physical dependence. This research creates a multidimensional measure of dependence that is based on theoretically grounded motives for drug use and is intended to reflect mechanisms underlying dependence. Data collected from a large sample of smokers (N = 775) indicated that all 13 subscales of the Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) have acceptable internal consistency, are differentially present across levels of smoking heaviness, and have a multidimensional structure. Validity analyses indicated the WISDM-68 subscales are significantly related to dependence criteria such as smoking heaviness and to 4th edition Diagnostic and Statistical Manual of Mental Disorders symptoms of dependence and relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Zaslow Martha J.; Weinfield Nancy S.; Gallagher Megan; Hair Elizabeth C.; Ogawa John R.; Egeland Byron; Tabors Patton O.; De Temple Jeanne M. 《Canadian Metallurgical Quarterly》2006,42(1):27
This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N=278) in low-income African American families were assessed when the child was in preschool, using maternal report, the Home Observation for Measurement of the Environment-Short Form (P. Baker & F. Mott, 1989; R. Bradley & B. Caldwell, 1984), and structured observational measures of parenting. Child outcomes reported by children, mothers, teachers, and direct assessment were collected 4 years later. All parenting methodologies showed some predictive value; however, observational parenting measures showed the strongest and most consistent predictions of child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
49.
McKay James R.; Alterman Arthur I.; Cacciola John S.; Rutherford Megan J.; O'Brien Charles P.; Koppenhaver Janelle 《Canadian Metallurgical Quarterly》1997,65(5):778
Ninety-eight male cocaine-dependent patients who completed an intensive outpatient program (IOP) were randomly assigned to either standard group counseling (STND) or individualized relapse prevention (RP) aftercare. Heavier cocaine and alcohol use during IOP and low self-efficacy predicted more cocaine use during the treatment phase of the study, whereas lifetime diagnoses of alcohol dependence, major depression, and any anxiety disorder predicted less cocaine use. Rates of complete abstinence during the 6-month study period were higher in STND than RP, whereas RP was more effective in limiting the extent of cocaine use in those who used during Months 1-3. Matching analyses indicated patients who failed to achieve remission from cocaine dependence during IOP and those with a commitment to absolute abstinence did better in RP than in STND, whereas patients with other abstinence goals did better in STND than RP. Several differences in experiences before cocaine use and "near-miss" episodes were also identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Adrian Field Karen Witten Elizabeth Robinson Megan Pledger 《Urban Policy and Research》2004,22(2):189-205
This article explores patterns of access to services, amenities and facilities in two neighbouring New Zealand cities. An area-level indicator of community resource access, based on priorities identified by caregivers of young children, is analysed alongside census data to examine associations with community resource access in each city. Analysis reveals variations in resource access between the two cities that could not be solely explained by population density. Associations were found between resource access and patterns of deprivation, population density, age, and families with children. Of particular note was a positive association between areas of higher levels of resource access and areas of higher levels of deprivation within cities. There were, however, higher overall levels of resource access in the city with a less deprived profile. These findings support action by both central and local government to ensure equitable resource distribution to promote local well-being. 相似文献