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31.
The role of brown adipose tissue in the mechanism of medium chain triglyceride (MCT)-induced thermogenesis was investigated.
Under anesthesia, the interscapular brown adipose tissue (IBAT) was excised in male Sprague-Dawley rats, and the animals were
fitted with gastrostomy tubes. After a 10-day recovery period, the animals were divided into two groups: one group received
a diet containing MCT as 50% of calories, and the other group received an isocaloric diet containing long chain triglyceride
(LCT). The diets were fed for 6 wk at a level of calorie intake that was 150% of the ad libitum intake of a parallel control
group. During the last week of the study, resting and norepinephrine (NE)-stimulated O2 consumption and CO2 production were measured in a Noyons diaferometer. At the end of 6 wk, the animals were weighed and killed. The individual
fat pads were dissected and weighed, and an aliquot of the right retroperitoneal fat pad was used to measure adipocyte size
and number. The results showed that body weight and adipocyte size (but not adipocyte number) were significantly smaller in
the MCT-fed compared to the LCT-fed animals. Resting as well as maximal NE-stimulated oxygen consumption values were significantly
higher in the MCT-fed than the LCT-fed rats. It is concluded that the enhanced thermogenesis induced by MCT persists despite
the absence of IBAT and that the phenomenon is likely related to more extensive oxidation of MCT-in contrast to LCT-derived
fatty acids, thus leading to increased oxygen consumption, enhanced dissipation of energy as heat and diminished efficiency
of weight gain and deposition of body fat.
Presented at the symposium on “Specialty Lipids and Their Biofunctionality” at the annual meeting of the American Oil Chemists'
Society, Philadelphia, May 1985. 相似文献
32.
Abstract The importance of liquid viscosity in chemical process design makes it one of the most measured transport properties. Nevertheless, in the pure-component database, no experimental data on liquid viscosity for nearly 50% of the compounds are available. Therefore, prediction methods for liquid viscosity of alkenes over a wide range of absolute temperature for each components are necessary. Moreover, experimental data measured at lower temperatures are often extrapolated to higher temperatures with erroneous results. To improve liquid viscosity prediction of experimental data to temperatures and carbon numbers, we propose an empirical rule for estimating the viscosity of alkenes compounds. A predictive method, based physical properties (absolute temperature and carbon numbers) as its inputs, to correlate liquid viscosity by the statistical analysis is proposed. For a group of 19 compounds, the mean average absolute deviation was 4.6% for 118 data points. These values are better than other predictive methods and show that the statistical analysis model is stable and can be used to obtain good predictions for compounds that were not used in the model calibration. 相似文献
33.
Z. Siri Z. Mustafa I. Hashim 《International Journal of Heat and Mass Transfer》2009,52(25-26):5770-5775
The effect of a feedback control on the onset of steady and oscillatory Bénard–Marangoni instability in a rotating horizontal fluid layer is considered theoretically using linear stability theory. It is demonstrated that generally the critical Marangoni number for transition from the no-motion (conduction) to the motion state can be drastically increased by the combined effects of feedback control and rotation. The role of the controller gain parameter on the Pr-Ta and Pr-R/Rc parameter spaces, dividing stability domains into which either steady or oscillatory convection is preferred, is determined. 相似文献
34.
Ismayadi Ismail Mansor Hashim Khamirul Amin Matori Rosidah Alias Jumiah Hassan 《Journal of Superconductivity and Novel Magnetism》2012,25(1):71-77
In this paper the effect of sintering temperature on Ni0.5Zn0.5Fe2O4 is examined closely. The evolution of toward magnetically ordered materials was to be tracked with the parallel evolving
microstructure subjected to sintering temperatures in an ascending order. The starting powder of Ni0.5Zn0.5Fe2O4 was prepared via mechanical alloying and later molded into toroidal samples. After each sintering, we observed the resulting
changes in the materials. The XRD data showed a single phase being formed as early as 600 °C and the peak intensity was increasing
with the sintering temperature indicating an increase in the degree of crystallinity. The BH hysteresis loops showed the evolution
from paramagnetism to moderate ferromagnetism to strong ferromagnetism with microstructural changes. For lower sintering temperatures,
the samples showed paramagnetic behavior dominating the samples. As sintering temperature increased, paramagnetic states decreased
and, at 900 °C, a moderately ferromagnetic state appeared. Sintering at 1000 °C produced a strongly ferromagnetic state giving
a well-formed sigmoid-shape hysteresis loop. 相似文献
35.
M. Z.M. Nor M. A. Noranizan N. L. Chin K. Hashim 《International Journal of Food Properties》2013,16(5):966-977
This work describes the effect of a repetitive cooking-chilling process on resistant starch content in crackers prepared from a mixture of fish and starch, which are popularly known in Malaysia as “keropok.” Three fish cracker formulations were prepared using tapioca, wheat, and sago starch. Up to four cycles of repetitive cooking-chilling increased the resistant starch content in all products; however, the hardness of chilled samples decreased, and their moisture content increased. For the fried samples, the texture became harder, the color turned darker, and linear expansion was reduced. The dried fish cracker samples prepared with sago starch yielded the highest resistant starch content. The results demonstrated that four cycles of repetitive cooking-chilling were able to enhance resistant starch in fish crackers. 相似文献
36.
This study investigated the role of age, marital status, gender, nationality, educational background and monthly income in drivers' comprehension of traffic signs. The populations sampled here were from five Arabian Gulf Countries. A total of 28 symbolic warning and regulatory signs were investigated. A questionnaire specially prepared to collect the necessary data was distributed to over 9000 drivers in the five countries; 4774 responded (53%). The results indicated substantial problems with the level of comprehension among the drivers about the traffic signs. The percentages of drivers who correctly identified the regulatory signs and warning signs were around 55 and 56%, respectively. Age, gender, education and income played major roles in determining drivers' comprehension of signs, whereas marital status showed no significant effect. Drivers who are young, female, those with lower levels of education or lower incomes understand the signs significantly worse than drivers who are older, male, with higher levels of education or higher incomes. Drivers from Europe and USA are significantly better than Asian and Arab drivers. These findings are believed to be important for the designers of road signs for international applications. 相似文献
37.
A relatively thermostable 22-kDa endoribonuclease (MAR1) was purified more than 10,000-fold from a mitochondrial extract of Leishmania tarentolae and the gene cloned. The purified nuclease has a Km of 100-145 +/- 33 nM and a Vmax of 1.8-2.9 +/- 2 nmol/min, depending on the RNA substrate, and yields a 3'-OH and a 5'-phosphate. Cleavage was limited to several specific sites in the substrate RNAs tested, but cleavage of pre-edited RNAs was generally independent of the addition of cognate guide RNA. The MAR1 gene was expressed in Escherichia coli or in L. tarentolae cells, and the recombinant protein was affinity-purified. The cleavage specificity of the recombinant enzyme from L. tarentolae was identical to that of the native enzyme. The single copy MAR1 gene maps to an 820-kilobase pair chromosome and contains an open reading frame of 579 nucleotides. The 18-amino acid N-terminal sequence shows characteristics of an uncleaved mitochondrial targeting sequence. Data base searching revealed two homologues of MAR1 corresponding to unidentified open reading frames in Caenorhabditis elegans (GenBankTM accession number Z69637) and Archaeoglobus fulgidus (GenBankTM accession number AE000943). The function of MAR1 in mitochondrial RNA metabolism in L. tarentolae remains to be determined. 相似文献
38.
The pathogenic significance of cell adhesion molecules (CAMs) in ulcerative colitis (UC) is largely unknown. Colonic expression of E-selectin, sialyl Lewis X (sLe(x)), and macrophage inflammatory protein-1x (MIP-1alpha) as well as serum concentrations of E-selectin and MIP-1alpha in UC were studied. Thirty patients with UC, 10 patients with irritable bowel syndrome, and 10 healthy subjects were included. Colonic biopsies were stained immunohistochemically, and blood concentrations were measured with an ELISA technique. Soluble E-selectin did not correlate with diagnosis or disease activity. MIP-1alpha was below the detection limit. Epithelial cells expressed all three molecules, both on surface membranes and intracellularly. sLe(x) staining was weaker (P = 0.0002) and MIP-1alpha staining stronger (P = 0.014) in UC patients than in controls. Leukocyte MIP-alpha staining correlated with diagnosis (P = 0.021), sLe(x) staining (P = 0.023), and colonoscopy (P = 0.018). It is shown that E-selectin, sLe(x), and MIP-1alpha are synthesized and expressed by epithelial cells, indicating that CAMs are not only involved in leukocyte extravasation and migration, but also in the interaction between leukocytes and colonic epithelium. This knowledge might contribute to the development of improved treatments in UC. 相似文献
39.
40.
A procedure for subspace stacking is proposed, and it is proved that the technique is equally successful for both linear codes and anticodes. It is demonstrated that families of errorcorrecting codes may be constructed using the proposed technique for stacking linear codes. Examples of such codes are given with rates better than the best known codes of identical Hamming distance and the same number of information digits. 相似文献