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21.
Lubica Sobotova Jana Jurkovicova Ludmila Sevcikova 《The Science of the total environment》2010,408(6):1264-1270
Objective
The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.Methods
The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, Leq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, Leq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).Results
Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).Conclusions
These findings highlight the association between road traffic noise and cardiovascular risk. 相似文献22.
Olusola O. James Sudip Maity M. Adediran Mesubi Lamidi A. Usman Kolawole O. Ajanaku Tolu O. Siyanbola Satanand Sahu Rashmi Chaubey 《国际能源研究杂志》2012,36(6):691-702
Dependence on fossil fuels for global energy supply has continued to generate concerns about climate change and sustainable development. It has motivated the search for carbon‐neutral alternative resources for the production of transportation fuels to replace crude oil. Although biodiesels have recently emerged as a close substitute to petrol diesel, their use in compression ignition engines designed to run on petro‐diesel fuels are linked to adverse effects on the engines' performance and life span. This informed efforts at upgrading biodiesel or direct conversion of triglycerides to hydrocarbon mixtures that are identical or similar to that of petro‐diesel through hydrodeoxygenation. Moreover, it seems that commercial methods for the conversion of triglycerides to diesel fuels depends on inputs (methanol and hydrogen) derived from fossil fuels. However, it will be desirable to do so without inputs from fossil fuels. Hence, reaction paths for direct conversion of triglycerides to on‐specification hydrocarbons fuels without hydrogen gas input are discussed and suggested strategies are in cognisance of green chemistry principles. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
23.
Glycerolysis of fats and methyl esters 总被引:3,自引:3,他引:0
The glycerolysis of methyl esters and triglycerides with crude glycerol, a coproduct from the transesterification of triglycerides,
was studied. Three procedures were followed for this conversion. The first procedure was a one-step glycerolysis with methyl
esters. The second procedure was a two-step process. This procedure involved an initial partial glycerolysis with methyl esters,
followed by fat glycerolysis. The third procedure was a simultaneous glycerolysis with methyl esters and triglycerides. In
the glycerolysis with methyl esters, the removal of methanol is vital to the production of mono- and diglycerides. Methanol
was removed either by drawing vacuum on the reactor or by stripping methanol out by means of an inert carrier gas (nitrogen).
Different molar ratios of methyl esters to glycerol were tested in the first two processes. At low concentration of methyl
esters, total conversion of methyl esters to mono- and diglycerides was achieved. As the concentration of methyl esters was
increased, the conversion of methyl esters to mono- and diglycerides was decreased. Furthermore, the ratio of mono- to diglycerides
was also higher at lower concentrations of methyl esters. The conversion of triglycerides in the two-step process with crude
glycerol was similar to a one-step fat glycerolysis with pure glycerol. The composition of different components and the ratio
of mono- to diglycerides were also comparable. 相似文献
24.
Synthesis and isolation of epoxy secondary amidesvia direct amidation ofVernonia galamensis seed oil
Kent A. A. Bryant Chukwuma P. Nwaonicha Mahmoud Hassan Melissa A. Anderson Folahan O. Ayorinde 《Journal of the American Oil Chemists' Society》1993,70(5):457-460
Vernonia galamensis oil, containing naturally epoxidized triglycerides, was reacted withn-butylamine,n-pentylamine andn-hexylamine to afford high yields of epoxidized secondary amides. Three reaction conditions were investigated: (i) reflux
with amines as solvents, (ii) reflux with hexane as the solvent and (iii) room temperature with the amines as solvents. Reactions
with amines as refluxing solvents were completed in 1–5 h, while those with hexane went to completion within 2 to 5 d. Room
temperature reactions were onlyca. 80% complete after several days. Reactivity was increased with higher amine homologs at both reflux and room temperature
reaction conditions. Isolated yields of epoxy-containing amides were about 80% with purity exceeding 96% in all cases. Spectroscopic
characterization of the previously unreported alkyl-vernolamides is provided. 相似文献
25.
Mohamed M. Soumanou Uwe T. Bornscheuer Ulrich Menge Rolf D. Schmid 《Journal of the American Oil Chemists' Society》1997,74(4):427-433
Structured triglycerides (ST) that contain medium- and long-chain fatty acids were synthesized by lipase-catalyzed interesterification
between tricaprylin and peanut oil. To select appropriate enzymes, we investigated nine commercial lipase preparations for
their ability to hydrolyze pure triglycerides as well as natural oils. Three microbial lipases from Rhizomucor miehei (RML), Candida sp. (CSL), and Chromobacterium viscosum (CVL) gave good results, and immobilized preparations were used in the interesterification. RML gave the highest yields of
ST (73%, 40°C), although its hydrolytic activity toward triolein was low. As the temperature was raised to 50°C, the yield
of ST increased to 79%. After 120 h reaction time, remaining activities were high for CSL (71%), moderate for CVL (48%), and
low for RML (20%).
Parts of this paper were presented as a poster at the Biochemical Engineering Conference IX, May 1995, Davos, Switzerland. 相似文献
26.
Peter Fairley John M. Krochta J. Bruce German 《Journal of the American Oil Chemists' Society》1995,72(6):693-697
Blends of butterfat and tripalmitin are of interest for use as moisture barriers in edible films. Tripalmitin was blended
with butterfat in the ratios 100:0, 90:10, 80:20, and so on through to 10:90 and 0:100. Crystal morphologies of squash and
smear preparations were determined by polarizing light microscopy. Samples were stored at 19–22°C and re-examined after 6
d and after 30 d. Morphology was strongly dependent on composition and the presence of a coverslip. Morphology was less dependent
on polymorphic form and age. Barrier properties depend more strongly on morphology than on polymorphic form. 相似文献
27.
Andrew Pinkerton Peter J Randall Patricia A Wallace Margaret M Vonarx Rodney J Mailer 《Journal of the science of food and agriculture》1993,61(1):79-86
A rapid X-ray spectrometric (XRS) method has been developed for the determination of the total glucosinolate content of oilseed rape and other Brassica oilseeds. The method is based on analysis for fully oxidised sulphur (S6+), which includes half the sulphur (S) in the glucosinolate molecule, and the S in sulphate. Results are highly correlated with glucosinolate content determined by glucose release, a standard method widely used in Australia. The relationship is total glucosinolates = (23·97 S6+ -9·43) r2 = 0·987, where the glucosinolate content is expressed as μmol g?1 and the S6+ content in mg g?1. The relationship is applicable to seed of any glucosinolate content and to meal, and is unaffected by changes in protein sulphur content. The correlation of glucosinolates with S6+ is shown to be closer than the correlation with total S. The latter correlation forms the basis of the existing XRS method, used within the European Community in recent years. The advantages of S6+ derive from the linearity of the regression and the elimination of errors caused by variation in protein content. The method should be valuable to the Australian oilseed industry because it allows the rapid screening of breeding lines to ensure low glucosinolate content and the assessment of deliveries for crushing and of meal. 相似文献
28.
Comparison of pulsed NMR and ultrasonic velocity techniques for determining solid fat contents 总被引:3,自引:0,他引:3
D. J. McCLEMENTS M. J. W. POVEY 《International Journal of Food Science & Technology》1988,23(2):159-170
An ultrasonic velocity technique has been compared with pulsed NMR'weight' and 'direct' methods of determining solid fat contents (SFC). Measurements were made at 18°C using samples 0–20% of rapidly cooled tristearin in paraffin oil, tristearin in sunflower oil and tripalmitin in paraffin oil. Correlations between the amount of triglyceride added and the SFC predicted by each of the techniques were always better than 0.995 ( n ± 13). The precisions of the ultrasonic technique (0.2%) and the weight method (0.3%) were significantly better than that of the direct method (0.7%). The ultrasonic technique may therefore offer a suitable alternative or adjunct to the established pulsed NMR technique for SFC determinations; it has considerably lower capital cost and a faster sampling rate. 相似文献
29.
中碳链脂肪酸甘油三酯具有降低体重、调节脂代谢、缓解疲劳等功效,其常温下为液态,为方便其在食品领域应用,以乳清蛋白、菊粉为壁材,采用喷雾干燥的方法制备中碳链脂肪酸甘油三酯微胶囊。通过单因素实验,考察复配壁材比例、壁材添加量、芯壁比、乳化剂添加量、复配乳化剂比例对中碳链脂肪酸甘油三酯微胶囊包埋率的影响,采用Box-Behnken设计响应面实验优化中碳链脂肪酸甘油三酯微胶囊的制备配方,并测定制备的中碳链脂肪酸甘油三酯微胶囊基本理化性质。结果表明:中碳链脂肪酸甘油三酯微胶囊最佳制备配方为乳清蛋白:菊粉3∶1(w/w)、乳化剂添加量0.4 g/100 mL、芯壁比1∶1(w/w)、复配壁材(乳清蛋白和菊粉)添加量14 g/100 mL、复配乳化剂(单甘酯∶羧甲基纤维素钠)1∶1(w/w),在此条件下制备的中碳链脂肪酸甘油三酯微胶囊包埋率可达95%,具有良好流动性、分散性及溶解性,粒径分布均匀,平均粒径为4.43μm。 相似文献
30.
Shelby L. Oke Kendrick Lee Rosemary Papp Steven R. Laviolette Daniel B. Hardy 《International journal of molecular sciences》2021,22(14)
The rates of gestational cannabis use have increased despite limited evidence for its safety in fetal life. Recent animal studies demonstrate that prenatal exposure to Δ9-tetrahydrocannabinol (Δ9-THC, the psychoactive component of cannabis) promotes intrauterine growth restriction (IUGR), culminating in postnatal metabolic deficits. Given IUGR is associated with impaired hepatic function, we hypothesized that Δ9-THC offspring would exhibit hepatic dyslipidemia. Pregnant Wistar rat dams received daily injections of vehicular control or 3 mg/kg Δ9-THC i.p. from embryonic day (E) 6.5 through E22. Exposure to Δ9-THC decreased the liver to body weight ratio at birth, followed by catch-up growth by three weeks of age. At six months, Δ9-THC-exposed male offspring exhibited increased visceral adiposity and higher hepatic triglycerides. This was instigated by augmented expression of enzymes involved in triglyceride synthesis (ACCα, SCD, FABP1, and DGAT2) at three weeks. Furthermore, the expression of hepatic DGAT1/DGAT2 was sustained at six months, concomitant with mitochondrial dysfunction (i.e., elevated p66shc) and oxidative stress. Interestingly, decreases in miR-203a-3p and miR-29a/b/c, both implicated in dyslipidemia, were also observed in these Δ9-THC-exposed offspring. Collectively, these findings indicate that prenatal Δ9-THC exposure results in long-term dyslipidemia associated with enhanced hepatic lipogenesis. This is attributed by mitochondrial dysfunction and epigenetic mechanisms. 相似文献