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The purpose was to establish a characteristic fingerprint of Eucommia ulmoides leaves extract, a feed additive, using high-performance liquid chromatography (HPLC), to provide a reference for its quality control. The HPLC method was used to determine the chemical constituents of 36 batches of Eucommia ulmoides leaves extract on a Sunfire C18 (4.6 mmx250 mm, 5 µm) column, with acetonitrile-0.1% formic acid in water as the mobile phase, at a flow rate of 1.2 mL/min, with an injection volume of 10 µL, a column temperature of 35 °C, and a detection wavelength of 254 nm. Eight peaks with better separation and peak shape in the chromatograms of 36 batches of Eucommia ulmoides leaves extracts were selected as the characteristic peaks to obtain the HPLC chromatograms of Eucommia ulmoides leaves extract. Based on the information of the control product, the precise relative molecular mass and the fragmentation ions, eight characteristic peaks were identified as the constituents of Eucommia ulmoides leaves extract. The results showed that a total of eight characteristic peaks were identified in the HPLC characteristic chromatogram of Eucommia ulmoides leaves extract, and seven chromatographic peaks of aucubin, geniposidic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, quercetin rutin, and isoquercitrin were identified. The study indicates that the characteristic chromatogram of Eucommia ulmoides leaves extract established in the experiment has achieved stable quality control and can provide reference for the quality evaluation of Eucommia ulmoides leaves extract as a feed additive. [ABSTRACT FROM AUTHOR]

Studying the dissociation of liquid hydrogen at extreme high pressure and temperature is very helpful for understanding its equation of state and thermodynamic properties. Based the previous ab-initio simulation results which were in good agreement with various experiments, the values of dissociation degree of hot dense hydrogen at different state points were calculated via the coordination number, and then the effects of dissociation in shocked deuterium on its thermodynamic properties were discussed. The results show that the deuterium is mostly a diatomic fluid blow 20 GPa, and almost a monatomic fluid above 53 GPa, with a dissociation of 11.5% and 90% respectively, and thus a fluid composed of D2 and D between 20 GPa and 53 GPa. Furthermore, two critical lines of liquid hydrogen in the T-p and T-P space when its dissociation nearly occurs or ends were mapped, and a suggestion that there is at least 50% dissociation at the onset of metallization in the dense liquid hydrogen was made. [ABSTRACT FROM AUTHOR]

Taking the typical yellow soil in Guizhou as the research object, four treatments were set up： no fertilization （CK）, single application of chemical fertilizer （NP）, 50% organic fertilizer instead of chemical nitrogen fertilizer [1/2（NPM）], and 100% organic fertilizer instead of chemical nitrogen fertilizer （M）. The effects of organic fertilizer instead of chemical nitrogen fertilizer on organic carbon and its active components, soil carbon pool management index, soil enzyme activity, and maize and soybean yield in yellow soil were studied in order to provide theoretical basis for scientific fertilization and soil quality improvement in this area. The results showed that the replacement of chemical nitrogen fertilizer by organic fertilizer significantly increased soil pH, organic carbon （SOC）, total nitrogen （TN） content, and C/N ratio. Compared with those in the CK and NP treatments, the content and distribution ratio of soil active organic carbon components and soil carbon pool management index （CPMI） were improved by replacing chemical nitrogen fertilizer with organic fertilizer, and the effect of replacing chemical nitrogen fertilizer with 50% organic fertilizer was the best. Compared with those in the NP treatment, the 1/2 （NPM） treatment significantly increased the contents of soil readily oxidizable organic carbon （ROC 333 , ROC 167 ）, dissolved organic carbon （DOC）, and microbial biomass carbon （MBC） by 22.90%, 8.10%, 29.32%, and 23.22%, respectively. Compared with those under the CK and NP treatments, organic fertilizer instead of chemical nitrogen fertilizer increased soil enzyme activities. The activities of catalase, urease, sucrase, and phosphatase in the 1/2 （NPM） treatment were significantly increased by 21.89%, 8.24%, 34.91%, and 18.78%, respectively, compared with those in the NP treatment. Compared with that of the NP treatment, the maize yield of the 1/2 （NPM） and M treatments was significantly increased by 44.15% and 17.39%, respectively. There was no significant difference in soybean yield among different fertilization treatments. Correlation analysis showed that soil SOC was significantly positively correlated with ROC 333 , ROC 167 , ROC 33 , DOC, MBC, and soil active organic carbon components, and CPMI was significantly positively correlated with soil organic carbon and its active components （ P <0.01）. Corn yield was significantly positively correlated with soil enzyme activity, CPMI, total organic carbon, and its active components （ P <0.05）. Therefore, from the perspective of yield increase and soil fertility, 50% organic fertilizer instead of chemical nitrogen fertilizer was conducive to improving soil quality and soil fertility, which is the key fertilization technology to achieve a high yield of crops in the yellow soil area of Anshun, Guizhou.

Objective: To investigate the effect of Astragalus membranaceus (AM) on endothelial-dependent (EDV) and non- dependent (EIV) vascular relaxation in ex vivo thoracic aortic rings of obese rats., Methods: Fifteen SD rats were randomized into 3 equal groups, namely the control group fed with normal chow, obese group with high-fat chow, and AM intervention group fed with high-fat chow and daily AM gavage. The rats were sacrificed after 6 weeks of feeding, and the aortic rings were dissected and cut into 3-mm rings. The response to acethylcholine (Ach) and sodium nitroprusside (SNP) were examined in organ bath. In ex vivo study, the aortic rings obtained from the control group and obese group were incubated with AM or vehicle for 3 h in organ bath before testing the EDV and EIV. The body weight and weight of the visceral fat in each group were recorded., Results: The weight of visceral fat was greater in the obese group than in the control group, and a 6-week AM treatment significantly reduced the fat tissue due to high-fat diet. The maximum EDV value was (87.0 - or + 3.5)% in the control group, (54.8 - or + 7.8)% in the obese group, and (69.8 - or + 5.7)% in AM intervention group; the EIV values were comparable between the 3 groups. After incubation with AM, the maximum EDV values of aortic rings obtained from the obese group were significantly increased from (55.6 - or + 8.3)% to (85.1 - or + 4.5)%., Conclusion: AM can improve endothelial dysfunction in obese rats, and the mechanism involves improved insulin resistance and increased endothelium-derived NO productor function.

Objective: To test the effect of Adiponectin on endothelium-dependent and non-dependent vasodilation in food-induced obese SD rats., Methods: Ten male Sprague-Dawley rats were divided into 2 groups: the rats in the control group (n=5) were fed with normal chow; The rats in the experimental group were fed with high fat chow (n=5). At the end of the sixth week, all rats were killed and the thoracic aortas were harvested. The vessel rings obtained from the obese rats were pre-incubated for 2 hours with adiponectin, or adiponectin plus L-NAME, or none of them, then equilibrated in Krebs-Henseleit solutions. Constriction of the vessel rings were induced by norepinephrine followed by relaxations with increasing doses of acetylcholine (for endothelium dependent vasodilatation, EDV) or sodium nitroprusside (for endothelium independent vasodilation, EIV). Vasorelaxation was expressed as percentage of residual of maximal contraction., Results: Acetylcholine (10(-8)-10(-4) mol/L) caused a concentration-dependent relaxation in all preconstricted aortic rings. Compared with the control group, the maximal endothelium dependent relaxation of the aortic rings in the obese rats was impaired (p<0.05). With Adiponectin, the relaxation response of aortic rings to acetylcholine improved (P<0.05). Sodium nitroprusside (10(-8)-10(-4) mol/L) induced relaxation (endothelium independent relaxation) did not differ statistically between the two groups., Conclusion: Impaired endothelium-dependent vasodilatation has been observed in food-induced obese rats and Adiponectin can improve the endothelial dysfunction in obese rats.