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Purpose: To investigate the hypoglycemic and hepatoprotective effects of Angelica dahurica polysaccharide (ADP). Methods: The contents of neutral sugar, total glyoxylate and total protein, molecular mass and monosaccharide composition of ADP were determined by the phenol-sulfuric acid method, the sulfuric acid-carbazole method, the Coomassie brilliant blue method, high performance gel permeation chromatography (HPGPC) and high performance liquid chromatography (HPLC), respectively. Type 2 diabetes mellitus (T2DM) was induced in rats by high-fat and high-sucrose diet feeding combined with injection of streptozotocin (STZ). Five groups of rats were set up: blank control, model, low-dose ADP (200 mg/kg mb), high-dose ADP (400 mg/kg mb), and positive control (200 mg/kg mb metformin). The rats in the blank control and model groups were gavaged with distilled water. After four weeks of administration, body mass, fasting blood sugar (FBG), oral glucose tolerance test (OGTT), fasting insulin (FINS), homeostatic model assessment for insulin resistance (HOMA-IR) and glycogen levels were measured, hematoxylin-eosin (HE) staining was used to observe hepatic histopathological changes, and commercial kits were used to determine lipid metabolism, oxidative stress and liver function indexes. Results: ADP had the following composition: (83.26 ± 0.67)% neutral sugar, (8.32 ± 1.25)% glyoxylate, and (0.64 ± 0.07)% protein, and its molecular mass was 10.28 × 103 Da. Monosaccharide composition analysis showed that ADP consisted of rhamnose, arabinose, galactose, glucose, mannose, glucuronide acid and galacturonic acid with a molar ratio of 0.09:0.45:0.43:1.00:0.05:0.53:0.08. ADP significantly increased body mass, blood glucose, FINS and glycogen levels of T2DM rats (P < 0.01), significantly decreased FBG and HOMA-IR (P < 0.01), improved liver histopathology, and significantly improved lipid metabolism, oxidative stress and liver function indexes (P < 0.01). Conclusion: ADP has hypoglycemic and hepatoprotective effects, probably through regulating abnormal lipid metabolism and oxidative stress.

There are some disadvantages in existing inverter-interfaced distributed generators (IIDG) low voltage ride-through control methods,such as unsatisfactory voltage support effects,single control objectives,and the risk of over-limiting the output current. In this paper,a low voltage ride-through control considering multiple control objectives is proposed. Firstly,the preset phase voltage is used as the constraint condition,and the voltage support equation is constructed to realize the voltage support control. Secondly,by restricting the magnitude of the negative sequence reactive current injected by the IIDG into the grid,the active output oscillation suppression control is realized. At the same time,to make full use of the remaining capacity of IIDG,the maximum active power output and current-limiting strategy are used to calculate the positive sequence active current reference value of the IIDG to ensure that the maximum active power output control is achieved under the premise that the output current of IIDG does not exceed the limit. The simulation results show that compared with the existing positive-sequence reactive current injection control method,the proposed low-voltage ride-through control method in this paper has a better fault control effect.

Due to the particularity of marine environment and submarine silt, the durability of stabilized submarine silt is one of the greatest concerns in application. Taking the ground improvement project of submarine silt in a certain project in Hong Kong as the reinforcement object, this paper studies the durability of submarine silt stabilized by a novel binder (called GS agent, G and S are the initials of gypsum and slag, respectively), and compares it with cement stabilized soil. Unconfined compression tests were conducted to investigate the strength attenuation of stabilized soils under dry-wet cycle and sulfate soaking. The results showed that the corrosion resistance coefficient of GS stabilized soil under dry-wet cycle was about 1.05 to 1.10 times that of the cement stabilized soil. Under sulfate attack, the cement stabilized soil completely disintegrated, while the GS stabilized soil still had a certain strength with corrosion resistance coefficients of 18.6% to 71.2%. Increasing the binder cement and curing time were beneficial to improving the durability of stabilized soil. Meanwhile, scanning electron microscopy backscatter (BES) test and X-ray diffraction (XRD) analysis were conducted to investigate the micro mechanism of durability of soils stabilized by GS agent and cement. It is found that the GS stabilized soil had a high degree of hydration, less porosity and more stable structure. [ABSTRACT FROM AUTHOR]

In this paper, a method coupling with test data is adopted for the first time to obtain the drive file for virtual test rig as accurate road excitation input for increasing the accuracy of fatigue simulation. The technique is then applied to the durability performance optimization of a real vehicle with the fatigue life of its parts improved. Comparisons between simulation results and durability test data show that the technique has high accuracy with less resource consumption and can effectively guide the structure design of vehicle. [ABSTRACT FROM AUTHOR]

With the development of global economy, the dramatically increased production of polyethylene terephthalate (PET) plastics has led to a remarkably increased amount of plastic waste. PET waste can be treated by landfill, incineration, or biodegradation. While landfilling and incineration may cause secondary pollution, biodegradation has since received increased attentions due to its environmental friendliness. Recent studies have indicated that the carbohydrate binding module (CBM) can effectively enhance the binding of PET degrading enzymes to PET, and consequently increasing PET degradation rate. Here we constructed a fusion protein Ba CBM2-Tfuc containing the Ba CBM2 from Bacillus anthraci and the cutinase Tfuc from Thermobifida fusca , by megaprimer PCR of whole plasmids (MEGAWHOP). Notabaly, the PET film degradation efficiency (at 60 ℃) of Ba CBM2-Tfuc was 2.8 times that of Tfuc. This study may provide technical support for constructing fusion proteins capable of efficiently degrading PET.

With the decrease of forest timber resources, the recycling of waste paper has received increasing attention. However, the stickies produced in the process of waste paper recycling may negatively affect the production of recycled paper. The biological decomposition of stickies, which has the advantages of high efficiency, high specificity and pollution-free, is achieved mainly through the enzymatic cleavage of the ester bond in the stickies components to prevent flocculation. Cutinase is a serine esterase that can degrade some components of the stickies. Previous research indicated that the anchor peptide tachystatin A2 (TA2) is able to bind polyurethane. In this study, the cutinase HiC derived from Humicola insolens was used to construct a fusion protein HiC-TA2 by megaprimer PCR of the whole plasmid (MEGAWHOP). The enzymatic properties and the degradation efficiency of the fusion protein on poly(ethyl acrylate) (PEA), a model substrate of stickies component, were determined. The results showed that the degradation efficiency, the size decrease of PEA particle, and the amount of ethanol produced by HiC-TA2 were 1.5 times, 6.8 times, and 1.4 times of that by HiC, respectively. These results demonstrated that TA2 improved the degradation efficiency of HiC on PEA. This study provides a useful reference for biological decomposition of stickies produced in the process of recycled paper production.

Objective: To establish the differential templates of the skeletal profiles for Shanghainese with normal occlusion in early permanent dentition., Methods: 71 lateral cephalometric radiographs of subjects with normal occlusion in early permanent dentition, aged from 11 - 15 years (37 females and 34 males) were traced. 23 skeletal landmarks were identified on the tracings, which afterwards were scanned on the computer. An x-y coordinate system was established: the tracing superimposed on sella rotated 7 degrees down from the sella-nasion line as the x axis and the vertical line through sella perpendicular to the x axis as the y axis. A special length/depth ratio was designed. The length/depth ratio of each graph were calculated. Steiner analysis was applied to check the difference between genders., Results: There was no difference between genders. The tracings were divided into three categories: short face, normal face and long face according to the mean and standard deviation of the ratio. The three types of tracings were superimposed on the x axis with sella registered. Three templates were created., Conclusions: The differences were apparent when the three templates were superimposed.