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The chemical composition, mineral composition and content, dissemination characteristics, particle size distribution, and occurrence state of rubidium element of a rubidium ore in Inner Mongolia Autonomous Region were studied by means of chemical multi-element analysis, optical microscope analysis, scanning electron microscope analysis and MLA (automatic analysis system of mineral parameters). The results show that Rb2O content in the ore is 0. 107%. The main minerals of the rubidium ore are albite, quartz, K-feldspar, mica and kaolinite. Rubidium mainly exists in mica and K-feldspar in the form of isomorphism. Mica contains 0.886% Rb2O, with a distribution rate of 47.49%, and K-feldspar contains 0.226% Rb2O, with a distribution rate of 52. 51%. The particle size of quartz in the ore is the largest. The embedded particle size of potash feldspar and aite is close, 0.74 - 1.2 mm. The particle size of mica is mainly distributed in 0.02 - 0.85 mm. It is difficult to separate the fine mica and the mica interspersed in feldspar or wrapped in feldspar, and it is also easy to produce mud, which is not conducive to the beneficiation and recovery of rubidium. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between serum leptin concentration with blood pressure and hypertension in different gender., Methods: A total of 343 non-hypertensive residents aged 30 to 65 were randomly selected from Zhejiang Province in 2014. Parameters including height, weight, waist, blood pressure, serum lipid and serum leptin concentration of participants were measured and determined by physical examination and laboratory detection in 2014 and 2017. The differences in serum leptin levels between the new hypertensive and non-hypertensive people were compared after three years. The relationship between serum leptin levels and hypertension was analyzed by Logistic regression., Results: In 2014 and 2017, concentration of serum leptin in females was significantly higher than that in males, and the blood pressure in males was higher than that in females. At the end of follow-up, 26 new cases of hypertension were found. Serum leptin levels were higher in the female hypertensive group than in the non-hypertensive group(P=0. 0289), whereas there was no statistical difference in males(P>0. 01). Regardless of gender, serum leptin was significantly positively correlated with body mass index(BMI) and waist-to-height ratio(WHtR)(P<0. 0001), and also had correlation with blood pressure. However, after adjusting for BMI or WHtR, the correlation between serum leptin and blood pressure disappeared(P>0. 01). Logistic regression also showed the similar result., Conclusion: Serum leptin is not directly related to blood pressure and hypertension, and the positive correlation between them may be explained largely by BMI and WHtR.

Objective: To investigate the effects of isocaloric diets with different percentage energy from fat on blood glucose and lipids in rats., Methods: Forty male SD rats were assigned to low fat group, normal fat group, medium fat group and high fat group using randomized blocks method. Rats in four groups were fed with isocaloric diets whose percentage energy from fat were 5%, 15%, 25% and 40% respectively for 10 weeks. Body weight and body length of rats were measured every week. Blood glucose, blood lipids and insulin were determined at 0, 5th and 10 th week. The perirenal fat and epididymal fat pad were separated and weighed at the end of the 10 th week and the body fat rate was calculated., Results: At the end of the 5th and 10 th week, there were no significant differences among four groups in body weight, Lee's index, body fat rate, insulin and low density lipoprotein cholesterol. At the end of the 10 th week, the level of blood glucose was higher for rats in the high fat group than those in the low fat group( P <0. 01). The level of total cholesterol, triglyceride and high density lipoprotein cholesterol were lower for rats in the high fat group than those in the low fat group( P < 0. 01). The level of blood glucose of the 10 th week was higher for rats in the high fat group than the level at the beginning( P < 0. 05). The level of total cholesterol, low density lipoprotein cholesterol and high density lipoprotein cholesterol of the 10 th week was higher for rats in the high fat group than the level at the beginning( P < 0. 01)., Conclusion: When rats were fed with a isocaloric diet and in the condition of normal growth, diet with high proportion of energy derived from fat would not lead to overweight in rats, whereas it may change the metabolism of blood glucose and lipids.

Objective: To investigate the influence of marginal zinc deficiency on obesity and provide the theory basis for the prevention and treatment of obesity., Methods: Thirty two male SPF SD rats were randomly divided into four groups. Four groups were supplied different doses of zinc. All rats were sacrificed after 6 weeks. Serum zinc, serum lipid, leptin, total antioxidant capacity( T-AOC), superoxide dismutase( SOD) and malondialdehyde( MDA) were detected., Results: From the 5th week, the serum zinc in low zinc group was significantly lower than that in low zinc pair-control group and control group( P < 0. 05), and marginal zinc deficiency model was set up. At the 6th week, body fat ratio of rats in low zinc group was significantly higher than that in low zinc paircontrol group and control group( P < 0. 05). The MDA in liver tissue of the rats in low zinc group and middle zinc group was significantly higher than that in control group( P <0. 05). The levels of T-AOC and SOD in the liver tissue in low zinc group and middle zinc group were significantly lower than that in control group( P < 0. 05). The oxidative stressof the rats in low zinc group and middle zinc group increased., Conclusion: Marginal zinc deficiency can increase the risk of obesity. Oxidative stress significantly increase in marginal zinc-deficient rats, which may be the main reason that marginal zinc deficiency increase the risk of obesity.

Objective: To investigate the association between body mass index(BMI), waist-to-height ratio(WHtR) and dietary fat with serum leptin concentration., Methods: A three-day 24-h dietary recall method was conducted on 513 participants aged30-65 years who were randomly selected from Zhejiang Province in 2014 to investigate usual fat intake. In addition, parameters including height, weight, waist and serum leptinconcentration of participants were measured and determined by physical examination and laboratory detection., Results: Concentration of serum leptin in women was significantly higher than that in men( P< 0. 001). Both BMI and WHtR were positively correlated with serum leptin level( men: r=0. 488 and 0. 576, women: r =0. 453 and 0. 333, P<0. 0001), but only correlation of WHtR that men(r=0. 354, P<0. 0001) and BMI in women(r=0. 321, P< 0. 0001) remained when BMI and WHtR were controlled respectively. Standardized partial regression coefficient of WHtR(β =0. 27) was higher than that of BMI(β=0. 21) in men while in women the coefficient of BMI(β=0. 26)was higher than that of WHtR(β = 0. 20). Serum leptin level was negatively correlated with total energy, total fat and MUFA in men(P<0. 05), but the correlation between total energy and leptin was disappeared when WHtR was controlled for. Serum leptin level was positively correlated with the proportion of PUFA from total energy and(PUFA +MUFA) ∶ SFA in women(P<0. 05), while only the correlation between the proportion of PUFA from total energy and leptin remained when BMI was controlled for., Conclusion: Obesity degree was gender-specifically positively correlated with serum leptin level, which indicated different obesity indicators should be used for men and women when analyzing serum leptin. Serum leptin was negatively correlated with total fat and MUFA in men, while positively correlated with the proportion of PUFA from total energy in women.