• Journal of Nutrition and Health
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• v.28 no.10
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• pp.967-975
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• 1995

To investigate effects of dietary fish oil and vitamin E level on the tissue levels of vitamin E and vitamin A and to see which tissue is sensitive to lipid peroxidizability, male Sprague-Dawley rats were fed experimental diets composed of either menhaden oil or soybean oil nad either low(equivalent to 17 mg $\alpha$-tocopherol) or high (equivalent to 140mg $\alpha$-tocopherol) vitamin E level for 4 weeks. Palsma TBARS per mg lipid was significantly elevated in rats fed fish oil with low vitamin E level compared to soybean oil-fed rats. TBARS levels of liver, heart, kidney and liver microsomes were also increased by feeding fish oil with low vitamin E level. Plasma TBARS level was significantly correlated with TBARS levels of liver, heart, kidney and liver microsome. Plasma vitamin E level of groups with vitamin E supplementation was elevated significantly as compared to the those without vitamin E supplementation, whereas vitamin E levels of liver, heart and kidney were not changed significantly. Plasma TBARS was negatively correlated with plasma vitamin E(r=0.5763, P<0.001) and A(r=-0.4523, P<0.01) and seems to be a good indicator of in vivo lipid peroxidative stress.

• Journal of Nutrition and Health
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• v.28 no.10
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• pp.1031-1039
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• 1995

Dietary mehaden oil enhances mucosal hyperplasia that normally occurs after massive small bowel resection. In contrast, dexamethasone and aspirin inhibit the adaptation response. In order to gain insight on the mechanism of these effects, male Sprague-Dawley rats weighing approximately 150gram were randomly divided into two groups and fed diet containing either 15% safflower oil or 14% menhaden oil and 1% safflower oil. Ten days later they were subjected to 70% jejunoilear resection. Immediately after surgery each group was further divided into two groups and receive either vehicle or 125ug/kg/day dexamethasone subcutaneously. All animals were sacrificed seven days after the surgery, and the remaining intestine was removed and divided at the anastomotic site. Dexamethasone, which decreased gut hyperplasia in both dietary groups, decreased both serum IGF-I levels and ileral PGE2 synthesis. Menhaden oil enhanced gut hyperplasia, but did not increase IGF-I or IGF-II levels in serum. PGE2 synthesis was lower in the ileum of menhaden oil-fed rats compared to that of safflower oil-fed rats. The effects of menhaden oil on adaptation did not apper to be mediated either through IGFs or PGE2 synthesis. Other factors could have played a role in enhancing adaptation following menhaden oil feeding.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.130-136
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• 2004

Presence of water in the lubricating oils could be one of the first indicators of potentially expensive and possibly catastrophic failure of the machine as it may cause displace the oil films to prevent the lubrication function of the oil or chemically react with many oil additives resulting in the oil degradation. In order to detect water content quantitatively in lubricating oils many methods and sensors has been developed. Among these, capacitive sensors including sensitive layer, whose dielectric factor changes according to the water content absorbed in the layer, are proposed mainly in the market. But these sensors are not sensitive to a high water content. Besides, the absorbing layer soils in time. In this work, an evaporation of water moisture from oil into air volume above lubricant surface and condensation of water vapor at a cooling surface was used to measure water content quantitatively in an lubricating oil. Laboratory test results of a prototype sensor were presented. Test results showed that the proposed method could be avaliable to measure a low levels of oil moisture.

• Tribology and Lubricants
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• v.24 no.1
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• pp.1-6
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• 2008

An experimental study was conducted to evaluate the viscosity characteristics of multi-grade engine oils in which contain diesel fuels. Unused engine oils of SAE 5W40, 10W40 and 15W40 were blended with a diesel fuel ratio of 5%, 10%, and 15%. The viscosity of a diluted engine oil was measured with temperature variation ranging from $-20^{\circ}C$ to $120^{\circ}C$ using a rotary viscometer. The diluted engine oil in which is blended to a diesel fuel plays an important role for decreasing an engine oil viscosity, which may decrease the oil film thickness and a load-carrying capacity. Test results show that the viscosity tends to fall for the increased temperature when engine oil is mixed with a diesel fuel. Especially, the viscosity at a low temperature zone is radically decreased compared with a high temperature zone. Based on the experimental results, the empirical equation that can predict the viscosity of diluted engine oil is expressed in the exponential function with the variation of the temperature and a fuel ratio of diluted engine oil. This equation may be possible to predict the limitation of the oil-fuel dilution rate at the concept design stage of the CDPF system, which doesn't affect the influence of the tribological components.

• Tribology and Lubricants
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• v.30 no.3
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• pp.168-176
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• 2014

This paper presents an engine oil change warning algorithm based on the test results of a small dip-stick-gage-type engine-oil-deterioration-detection sensor, software to realize the algorithm and a display device to apply the software. The algorithm determines the engine oil deterioration condition from the rate of change in the dielectric constant based on the average measured capacitance at $80^{\circ}C$ after the engine stops. The rate of change in the dielectric constant at the time for oil change correlates with the time that one of recommended warning limits for engine oil physical properties such as TAN (Total Acid Number), TBN (Total Base Number) and viscosity is first reached. At this point, a warning signal for oil change appears on the display device like a smart-phone or individual display device. The frames of smartphone app have three stages. The user can directly input all of the thresholds into the frame of the smartphone app. The screen of the display device comprises one frame for each warning signature with the related message. The user can input the thresholds to the device through a USB cable connected to a personal computer.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1183-1188
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• 2005

Several lipases of commercial grade were screened to catalyze the methanolysis of castor oil, and an immobilized Candida antarctica (Novozym 435) had the highest activity among the lipases tested. To enhance the yield of methyl ricinoleate, several reaction parameters were optimized. The optimum temperature was $50^{\circ}C$, and the original water content of lipase was sufficient to maintain the activity of lipase, and additional water supplied inhibited the methanolysis of castor oil. Because the lipase was deactivated by methanol, the reaction was tested by three-step addition of 1 molar equivalent of methanol to the oil. However, the oil was not completely converted to its methyl esters. The final reaction mixture using 3 molar equivalents of methanol to the oil consisted of $70\%$ methyl ricinoleate, $18\%$ monoricinoleate, $11\%$ diricinoleate, and trace triricinoleate at the equilibrium state. The yield of methyl ricinoleate was $97\%$ at 6 molar ratio of methanol to the oil with 300g of castor oil and 6g of immobilized Candida antarctica at $50^{\circ}C$ within 24 h.

• The Journal of Asian Finance, Economics and Business
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• v.4 no.2
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• pp.19-23
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• 2017

It is undisputable that crude oil and its price fluctuations are major components that affect most of the countries' economies. Recent studies have demonstrated that beside the impact that crude oil price fluctuations have on common macroeconomic indicators like gross domestic product (GDP), inflation rates, exchange rates, unemployment rate, etc., it also has a strong influence on stock markets and their performance. This relationship has been examined in a number of settings, but it is yet to be unraveled in the Omani context. Accordingly, the main purpose of this study is to examine the possible effect of the oil price fluctuations on stock price movements. The study applies Toda and Yamamoto's (1995) Granger non-causality test on the daily Oman stock index (Muscat Securities Market Index) and oil prices between the period of 2 January 2003 and 13 March 2016. The results indicated that the oil price fluctuations have a significant impact on stock index movements. However, the stock price movements do not have a significant impact on oil prices. These findings have significant implications not only for the Omani economy but also for the economy of similar countries, particularly in the Gulf Cooperation Council (GCC) countries. The latter should carefully consider their policies and strategies regarding crude oil production and the generated income allocation as it might potentially affect the financial markets performance in these countries.

• Journal of Nutrition and Health
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• v.13 no.4
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• pp.159-166
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• 1980

Methods for the determination of sterols in sesame oils were studied. The sesame oils were saponified and the sterols isolated from the unsaponifiable matter by Florisil column chromatography, and the individual components were determined by means of gas chromatography. Campesterol, ${\beta}-sitosterol$, stigmasterol were found in sesame oil including unknown Ⅰ and Ⅱ. The use of SE-30 gas chromatographic column allows the slow elution, duplication of peaks and relatively low reproducibility, therefore, 3% OV-17 was suitable for the sterol analysis. The result of this study showed that contents of sterols in sesame oil were campesterol 8.4%, stigmasterol 4.5%, ${\beta}-sitosterol$ 33.9% and others 53.0% involving 8.8% of unknown I and 44.3% of unknown Ⅱ. There has been no specific test available for identifying the sesame oil among common edible oils. But the ratio of sterols in sesame oils allowed the estimation of genuiness. The ratio of sterols vs. campesterol in genuine sesame oils were stigmasterol 0.3- 0.6, ${\beta}-sitosterol$ 3.0-3.8 and unknown Ⅱ 3.0, respectively. The 65 samples were composed of genuine sesame oil 40%, mixed rape seed oil 3%, cotton seed oil 1. 5% others were reused soybean oil or re-extracted oil.

• Korean Journal of Microbiology
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• v.39 no.2
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• pp.102-107
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• 2003

With the enrichment culture technique, bacterial strains which degrade diesel oil were isolated from soil contaminated with diesel oil. One of the isolates named GENECO 1 showed the highest activity for emulsification of diesel oil as well as the highest growth rate. This strain, GENECO 1, was identified as a Pseudomonas sp. based on its biochemical, physiological characteristics and 16S rDNA sequences. The optimal cultural conditions for cell growth and oil emulsifying activity of its culture were as follow; $30^{\circ}C$ for temperature, 7.0 for pH. Diesel oil degradation was analysed by the gas chromatography. More than 95% of 1% treated diesel oil were converted into a form no longer extractable by mixed organic solvents after 96 hours incubation.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.462-469
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• 2007

Isolation and application of oil-degradation microbes from the oil-contaminated soil and the determination of optimal operation conditions about the peat moss, the addition for the oil-biodegradation. After all experiments, we have acquired three important conclusions: First, we found out the 4 microbes, Pseudomonas fluorescens, Pseudomonas aeruinosa, Kurtia sp., Bacillus ceres, with excellent capability for the oil-degradation; Second, the optimal operating conditions of the peat moss for TPH treatment were pH $7{\sim}8$, temperature $25{\sim}30^{\circ}C$, water content 20%, mixing 2 times/ day, addition volume 2%; Third, in case of the application to the oil-contaminated soil with 4 mixed microbes, the removal efficiency of TPH was increased from 54% to 83% in oil-contaminated soil and from 65% to 85% in oil-contaminated soil with the peat moss.