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11.
Although 40% of US women indicate they are currently trying to lose weight, the association between intentional weight loss and longevity is unknown. The authors analyzed prospective data from 43,457 overweight, never-smoking US white women aged 40-64 years who in 1959-1960 completed a questionnaire that included questions on weight change direction, amount, time interval, and intentionality. Vital status was determined in 1972. Proportional hazards regression was used to estimate mortality rate ratios for women who intentionally lost weight compared with women who had no change in weight. Women who died within the first 3 years of follow-up were excluded. Analyses were stratified by preexisting illness and adjusted for age, beginning body mass index, alcohol intake, education, physical activity, and health conditions. In women with obesity-related health conditions (n = 15,069), intentional weight loss of any amount was associated with a 20% reduction in all-cause mortality, primarily due to a 40-50% reduction in mortality from obesity-related cancers; diabetes-associated mortality was also reduced by 30-40% in those who intentionally lost weight. In women with no preexisting illness (n = 28,388), intentional weight loss of > or = 20 lb (> or = 9.1 kg) that occurred within the previous year was associated with about a 25% reduction in all-cause, cardiovascular, and cancer mortality; however, loss of < 20 lb (< 9.1 kg) or loss that occurred over an interval of > or = 1 year was generally associated with small to modest increases in mortality. The association between intentional weight loss and longevity in middle-aged overweight women appears to depend on their health status. Intentional weight loss among women with obesity-related conditions is generally associated with decreased premature mortality, whereas among women with no preexisting illness, the association is equivocal.  相似文献   
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13.
In this study, a novel organic–inorganic hybrid compound with AgNO3 and 2,3-pyridinedicarboxylic acid (H2pydc), [Ag26-pydc)]n (1) has been synthesized. The molecular structure of complex has been determined by the single crystal X-ray diffraction. The complex has been observed to crystallize in the monoclinic space group P21/c. The asymmetric unit of compound consists of two crystallographically different Ag(I) centers and one pydc ligand. The Ag1 and Ag2 adopt tetrahedral and T-shaped geometries, respectively. At the same time, the silver(I) compound consists of a fish bone similar to the 1D silver cluster. Furthermore, novel coordination mode shown by H2pydc indicates that the crystal exhibits photoluminescence in the solid state at room temperature.  相似文献   
14.
ABSTRACT

Two lignites and one bituminous coal were extracted with benzene, toluene and pyridine at both sub and overcritical conditions in a specially designed experimental system which enabled easy solid-liquid separation. Extract yields increased somewhat at overcritical conditions due to more thermal decomposition. The differences between the power of the solvents were not apparent for the lignites, whereas the solubility in pyridine of the bituminous coal was very much higher than those in benzene and toluene. The amounts of oils, asphaltenes and preasphaltenes in the extracts depended on the type of coal and the solvent.  相似文献   
15.
ABSTRACT

The extraction kinetics of two lignites and one bituminous coal with benzene, toluene and pyridine were studied at both sub and supercritical conditions in a batch reactor equipped with a coal basket. The time-extract yield data of lignites at supercritical conditions could'nt be treated due to severe thermal decomposition and heating-up effects. The data for Zonguidak coal and those for subcritical extraction of Cizre lignite could be fitted into a first order rate equation with the rate constants changing 0·02-0·05 min?1 range.  相似文献   
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17.
Design, synthesis, and properties of a novel donor-acceptor-donor type low-voltage-driven green polymeric electrochrome, P1, which is based on 8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-11-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7-yl)acenaphtho[1,2-b]quinoxaline (1) are highlighted. It is noted that P1 has an ambipolar (n- and p-doping processes) character in 0.1 M tetrabutylammonium hexafluorophosphate/dichloromethane solution and switches to a transmissive blue state upon oxidation. Furthermore, this new polymeric electrochromic candidate exhibits high redox stability, high coloration efficiency and/or contrast ratio, high percent transmittance (%T) and low response time (1.0 s) with a band gap of 1.10 eV-1.25 eV.  相似文献   
18.
In this article, the potential utilization of hazel nut shell as a combustible residue was studied. To obtain liquid and gaseous products, the hazel nut shell was subjected to pyrolysis and it was converted to 49.3 % (w) gaseous and 20.0 % (w) liquid products at 475 °C for 7.5 minutes in a simple pyrolysis device The kinetic model used in the present study was based on fractional weight loss for each pyrolysis step. The simple fast pyrolysis was compared with TGA technique.  相似文献   
19.
This experiment was carried out to evaluate the effects of vitamin E supplementation on growth, non-carcass components and retail cut percentages, and meat quality traits of Awassi male lambs at approximately 8 months of age. The lambs were divided into two groups as control (CG, n=12) and experimental (VG, n=12) at the beginning of the fattening period. The CG and VG lambs were fed with a concentrate and grass hay close to ad-libitum by biweekly adjustment of the amount offered. In addition, the VG received a supplement of 45 mg vitamin E per lamb per day during a 75-day fattening period. Inital weight, final weight, daily weight gain and feed conversion efficiency were 31.8±1.40 kg, 45.5±1.37 kg, 183±13 g and 7.6 for CG, 32.5±1.45 kg, 46.7±1.42 kg, 189±15 g and 7.0 for VG, respectively. Vitamin E supplementation did not have a statistically significant effect on animal performance traits, non-carcass components and retail cut percentages, but produced an 8.1% improvement in feed conversion efficiency. After slaughter, carcasses were chilled at 4?°C for 24 h. Then, the carcasses were dissected into wholesale cuts, and m. longissimus dorsi (LD) muscles excised. The samples of muscle were subjected to moisture, protein, ether extract and ash analyses. Samples were cooked for shear test and cooking yield measurements. There were no significant differences between CG and VG lamb groups in chemical composition of meat samples from the LD muscles. Though the influence of vitamin E supplementation on color parameters (L*, a*, b*) was not statistically significant, the mean a* (redness) values decreased on days 2 and 4 and increased on days 7 and 12 of the storage period. However, the a* values of muscles from the VG were higher than those grouping CG. L* and a* values in LD muscle from vitamin E-treated lamb groups were also preserved for a period of 12 days of maturation. In this study, drip loss was relatively preserved by vitamin E supplementation to the diet of animals. The results showed that vitamin E supplementation to the diet of Awassi male lambs at an inclusion rate over the amount of nutritional recommendations relatively reduced lipid oxidation, drip loss and tended to maintain meat redness.  相似文献   
20.
This research was carried out to determine the effects of vitamin E supplementation on meat quality traits of approximate 8 months of age Morkaraman male lambs. The lambs were divided into two groups-control (CG, n=7) and experimental (VG, n=6)-at the beginning of fattening period. The diet given to the CG and VG consisted of concentrate and grass hay. In addition, the VG received a supplement of 45 mg vitamin E per lamb in a day during a 75-day fattening period. At the end of the study, average daily weight gain and feed conversion efficiency values as to feed basis were found to be 208 g and 6.3 for CG and 223 g and 6.0 for VG groups, respectively. Vitamin E supplementation resulted in 8.8% improvement in feed conversion efficiency. In the same way, vitamin E supplementation resulted in 6.7% increase in daily weight gain. Slaughter and carcass characteristics of lambs were also determined, but fattening performance, slaughter and carcass characteristics were not significantly different between groups. The effects of vitamin E on meat characteristics, meat colour (L*, a* and b*), thiobarbituric acid reactive substances content (TBARS), drip loss and pH were determined using m. longissimus dorsi (LD) muscles obtained from CG and VG. Though the effect of vitamin E supplementation on most of the meat quality traits was not statistically significant (P>0.05), L* and a* values in LD muscle from VG were preserved for a period of 12 days of maturation. In addition, a* (redness) tended to increase slightly. TBARS values in samples from CG were found to be higher than those of vitamin E treatment group. In this study, it was also concluded that drip loss was relatively preserved by vitamin E supplementation. In conclusion, vitamin E supplementation of Morkaraman male lambs at an inclusion rate over the amount of nutritional recommendations, significantly reduced lipid oxidation, drip loss and tended to maintain meat redness.  相似文献   
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