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Objective To investigate the antibacterial performance and biocompatibility of silver nanoparticles-coated root canal nickel titanium instruments(AgNPs-NiTi). Methods AgNPs-NiTi was prepared using pulse electrochemical deposition. The morphology of AgNPs-NiTi was observed using field emission scanning electron microscopy(FE-SEM), and the elemental composition and content were analyzed using X-ray diffraction(XRD)and energy dispersive spectroscopy(EDS). The mechanical properties of AgNPs-NiTi were tested. After Co-culturing AgNPs-NiTi with E. faecalis, the antibacterial effect was detected by colony-forming units method. By constructing an in vitro model of E. faecalis biofilm in the root canal of teeth, the antibacterial effect of AgNPs-NiTi was observed using FE-SEM and live/dead bacterial staining. In addition, AgNPs-NiTi was co-cultured with Raw 264.7 cells, and its cytotoxicity was detected by CCK-8. Results The pulse electrochemical deposition was used to construct a silver nanoparticle(AgNPs)coating on NiTi instruments with no significant change in the mechanical properties. AgNPs-NiTi significantly inhibited the proliferation of E. faecalis and damaged E. faecalis biofilm in the root canal. AgNPs-NiTi had no significant influence on the proliferation of Raw264.7 cells and had no cytotoxicity. Conclusion The mechanical properties of AgNPs-NiTi are similar to those of nickel titanium instruments. AgNPs-NiTi inhibits E. faecalis proliferation with good biocompatibility.

The effect of baking degree on the change of seven chlorogenic acid compounds in 10 different origins (origin 1: Yunnan, origin 2: Africa and America) of Cardim coffee. The content of chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B, isochlorogenic acid C and 5-ferulicquinic acid in green coffee and baked coffee were determined by high performance liquid chromategraphy (HPLC). The optimum extraction conditions of seven chlorogenic acid compounds were optimized by response surface methodology. 100 mL 0.1% phosphoric acid solution was extracted in water bath for 30 min, and the calibration curves of the seven chlorogenic acid compounds showed good linearity with correlation coefficients of above 0.999 4 in the range of 2~150 mg/L. Limit of the detection (LOD) and the limit of the quantitative (LOQ) were 0.005~0.5 mg/g and 0.02~2 mg/g respectively. The content of chlorogenic acid in green coffee beans was the highest, followed by 5-ferulicquinic acid. With the increase of baking degree, the content of chlorogenic acid and 5-ferulicquinic acid decreased significantly (P

Small molecular sugars are a group of sugars with low molecular weight, mainly including monosaccharides, disaccharides, and other oligosaccharides with low degree of polymerization. Small molecular sugars are commonly used as food additives in the food industy, including providing sweetness, improving food texture and optimizeing food processing adaptability. In addition, some small molecular sugars also have unique physiological functions that can be used to regulate the nutritional quality of food. Starch is the most common staple component in food, and starch and its modified derivatives are also widely used as food ingredients in food categories such as sauces, dairy products, beverages, and meat products. The composite system of small molecular sugar and starch is widely used in food. The addition of small molecular sugar has an important impact on the properties of natural starch, and plays an important role in regulating the quality of starch-based foods. This article mainly introduces the common small molecular sugars in food and their effects on the main physical and chemical properties of starch (gel texture, transparency, coagulation, gelatinization, freeze-thaw stability, aging, digestion, etc.), with emphasis on the impact of different types and amounts of small molecular sugars on the properties of starch from different sources. This paper aimed to provide reference for the application of small molecular sugars in starch based foods.

Deep learning technology is widely used in the field of number recognition.It constructs neural network model through deep learning technology,nonlinear transformation activation function in neurons,different activation functions with different parameter initialization strategies,trains MINIST handwritten data set,constructs analysis model and recognizes numbers in images,reduce the dimension of a large amount of data into a small amount of data,and ensure the effective retention of image features.Through the analysis of image data,adding the feature conversion process,using the gradient descent optimizer to build a network structure and reduce the dimension of data,which can effectively avoid over fitting.Cross-entropy verification is used to compile and train the model,and the output classification results are further analyzed.Through the K-nearest neighbor classification algorithm,KNN classifier is set to further improve the accuracy of classification and prediction.Through MNIST data set experiment,the recognition rate is about 96.2%.The K-nearest neighbor algorithm(KNN) is introduced into the output layer,combined with the full connection layer and softmax layer of traditional convolutional neural network(CNN).After cross verification,the recognition rate is 99.6%.

Objective: Improvement of the baking quality of the multi-grain pre-blent bread flour. Methods: On the basis of the previous study on the preparation of low glycemic index multi-grain pre-blent bread flour with oat flour, chickpea flour and wheat flour as the main raw materials, this study employed single factor experiment and response surface methodology to optimize the formula of the pre-blent bread flour. Results: The optimal concentration of xanthan gum, gluten, maltose amylase and ascorbic acid were 0.78 g/100 g, 3.42 g/100 g, 200.00 mg/kg and 171.70 mg/kg, respectively. The specific volume and hardness of the prepared bread were （2.21±0.03） mL/g and （15.97±0.69） N, respectively, which were closed to the bread made with pure wheat flour. The sensory evaluation results （including odor, internal structure, taste and overall acceptability） of the bread prepared from the multi-grain pre-blend flour were better than that of bread made from pure wheat flour. Conclusion: The formula of multi-grain pre-blent bread flour optimized by this study can be used in industrialization.

Objective To clarify the association between Fas gene polymorphisms and the level of soluble Fas(sFas) in the serum of rheumatoid arthritis (RA) patients in southwest China. Methods Fas rs2234767 and rs1800682 single mucleotide polymorphisms(SNP) were genotyped in a case-control study with 183 RA patients and 195 controls, using polymerase chain reaction restriction fragment length polymorphism(PCR-RFLP). sFas level in peripheral blood of RA patients and healthy people with different genotypes were detected by ELISA. Results There was no statistically significant difference between the patients with RA and the healthy subjects with respect to Fas rs2234767 and rs1800682 genotype distribution. However, patients carrying the rs1800682G/G genotype had a significantly decreased sFas level in serum compared with those carrying the AA genotype (P＜0.05). Conclusions Fas polymorphisms do not represent a major genetic risk factor for RA susceptibility. However, Fas rs1800682 polymorphism may influence sFas level in serum and response in patients with rheumatoid arthritis of Chinese population in southwest.

Objective To explore the effects of Colla corii asini (CCA) (common name E’jiao) on lung function and pathological injury of the lung tissue in rats with chronic obstructive pulmonary disease (COPD). Methods Twenty-five rats were randomly divided into the control group, COPD model group and treatment group with low, medium and high-doses of CCA (1, 2, 4 g/kg), with 5 rats in each group. The COPD model group and treatment groups were modeled by cigarette smoke exposure with a concentration of (1 100±10)mg/m3 once a day, 90 minutes each time, for 48 consecutive weeks. After the end of the next day, the CCA groups were given by daily oral gavage treatment for 28 days. Lung function was detected by animal lung function instrument and the pathological changes of the lung tissue were assessed by HE staining and microscopy. Results Compared with the control group, TV, EV, Te, RT, EEP and Penh were significantly increased in the COPD model group(P＜0.05), while PEF, PIF, MV, EF50 and f(B) were significantly decreased (P＜0.05). Inflammation and pathological changes of emphysema were observed, and lung tissue lesions were aggravated. Compared with the COPD model group, Te, RT and Penh were significantly reduced in the high-dose CCA group (P＜0.05), while MV, PIF and EF50 were significantly higher (P＜0.05). Less infiltration of inflammatory cells, less alveolar expansion and fewer pulmonary bullae were observed in high-dose CCA-treated rats. The degree of emphysema was reduced, and pathological damage to lung tissue was clearly alleviated. Conclusions CCA improves lung function and alleviates the inflammatory response of the lung tissue in COPD rats.

Skin is the largest organ of human, which can reflect host's health condition. Dermatovenereology is an important clinical discipline which focus on the profile of morphology. The challenge of learning is too much content but limited teaching hours. As to medical students, they may often feel dull and lose learning interest. How to arouse the enthusiasm and autonomy of medical students, and improve teaching effectiveness is one of difficulties in clinical teaching of dermatovenereology so draw attention by faculty as a potential orientation of education remodeling This paper aims for exploring a new teaching method, ‘diagnosis-initiated mode’, which may stimulate their interest in the learning of dermatovenereology.

A ternary alloy strengthened by the phase with long period stacking ordered (LPSO) structure with composition of Mg97.5Gd1.9Zn0.6 (atom fraction/%) was prepared by conventional permanent mold casting. The microstructure evolution and mechanical properties in as-cast, as-annealed, as-extruded and extruded-T5 alloy were systematically investigated by OM,SEM,TEM and electronic universal testing machine. The results show that the as-cast microstructure of the alloy consists of the α-Mg matrix, (Mg,Zn)3Gd eutectic and lamellar 14H-LPSO phase. Annealing at 510℃ results in the transformation of (Mg,Zn)3Gd into the block-shaped 14H-LPSO phase. According to the distribution and morphology of the 14H-LPSO phase observed in the microstructure after annealing, the peritectoid transformation (Mg,Zn)3Gd +α-Mg→14H-LPSO possibly occurs during annealing. The lamellar 14H-LPSO and β' p precipitates have also been observed in the alloy during extruded-T5 treatment. Under the combined action of 14H-LPSO toughening and precipitation strengthening, the aged sample shows the best tensile properties at room temperature:ultimate tensile strength of 361 MPa, yield strength of 216 MPa and elongation of 6.9%.

Cellulose graphene composite aerogels (CMC/GA) were prepared by one-step hydrothermal reaction based on graphite oxidation with the addition of low cost carboxymethyl cellulose. The functional group structure and microstructure of CMC/GA were characterized. The mechanism and capacity of the adsorption of Methylene Blue (MB) were investigated by CMC/GA in water. The results show that the higher temperature and higher initial concentration of MB are beneficial to the adsorption of CMC/GA. The adsorption isotherm is fitted with Langmuir model, the adsorption activation energy of the system is 57.951 kJ·mol-1, indicating that the adsorption of MB by CMC/GA is monolayer and belongs to chemical adsorption. The adsorption kinetics of MB is fitted with pseudo-second-order kinetics model. The intrapartical diffusion model of MB with different concentration shows that the adsorption process of CMC/GA for MB can be divided into two stages:macroporous diffusion and microporous diffusion, and the diffusion rate of macroporous diffusion is obviously higher than that of microporous diffusion.

Objective To investigate the teaching demands and practical effects of rotation in department of dermatology as well as demands for case database on eight-year medical students at Peking Union Medical College (PUMC). Methods From January 2017 to January 2019,the questionnaire survey was issued to the eight-year medical students of the 2011 to 2014 grade,which investigated the demands of the rotation,the difficulty in learning, the degree of mastery and demands for case database. Results A total of 101 valid questionnaires were received,which showed that the eight-year medical students at PUMC had a strong interest in the diagnosis and treatment of common and uncommon skin diseases as well as medical cosmetology. Autoimmune bullous disease was the most difficult chapter to learn. The eight-year medical students at PUMC had a strong demand for dermatology case database. They hoped to share it electronically. The most interesting content in the database was allergic skin disease. Conclusions The difficulties and weakness in dermatology teaching for eight-year medical students at PUMC and students' demands for dermatology case database are initially clarified,which may support is the improvement of learning outcome in dermatology.

BLADE is the commercial name of a spin-echo imaging technique that uses periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) k-space trajectory. In this study, the efficiency of using BLADE to improve hippocampal imaging in mental patients was assessed. The hippocampi of 47 mental patients were imaged on a 3.0 T scanner along the oblique coronal orientation using the T2WI TSE and T2WI FLAIR sequences with or without the use of BLADE. The same four sequences were also used to scan a standard American College of Radiology (ACR) phantom according to the ACR standards. The hippocampal images were scored by two radiologists using a 5-point scale, in terms of motion artifact, pulsation artifact, perceptive coarseness and image quality. The outcomes were compared between the sequences by two-sample Wilcoxon tests. The images of the phantom were evaluated semi-quantitatively for high contrast spatial resolution (HCSR) and low contrast object detection detectability (LCD) by counting the number of hole arrays and spokes that could be detected. The results showed that, compared to the conventional sequences, the sequences combined with BLADE technique showed significantly reduced motion and pulsation artifacts (p

OBJECTIVES This study was to investigate the change of inflammatory markers and fatigue substance of muscle damage on different resistance exercise intensities. METHODS The subjects were 7 students (age, 21.0 ± 1.56) in physical education department C University in Gyeongnam. The same amount of exercise was applied to each subject by low and high intensity resistance exercise. Inflammatory and muscle damage markers were based on IL-6, CRP, Myoglobin, CK and LDH. The changes of inflammatory and muscle damage markers on different exercise intensities were measured pre and immediately post exercise and during recovery periods. Blood was collected at each time and analyzed. RESULTS The IL-6 level was significantly lower (0.526) after 24 hours than before exercise in the high intensity exercise. Regardless of the difference in exercise intensities, the change was significantly higher(p

BACKGROUND In previous studies, due to the limited samples with specific origins and limited methods for measurement, the genesis of serpentinite-related green nephrite and its relationship with dolomite-related nephrite were unclear. OBJECTIVES To understand the genesis of serpentinite-related green nephrite. METHODS Green serpentinite-related nephrite deposits have been collected from Qinghai province in China, Russia, Canada, Australia, New Zealand and Pakistan for systematic analysis. X-ray Diffraction (XRD), Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), Electron Microprobe Analysis (EMPA), X-ray Fluorescence Spectrometry (XRF) and Stable Isotope Mass Spectrometry were employed. RESULTS ① Serpentinite-related green nephrite is mainly composed of tremolite with minor quartz, talc, biotite, chromite, chlorite, and garnet. ② O-H isotopic values of samples (δD=-69.763‰--29.251‰, δ18O=4.7‰-13.4‰) indicate that the ore-forming fluids are mainly metamorphic water. ③ whole-rock major elements of Fe2+/(Mg+Fe2+)values range from 0.11 to 0.32. The contents of Cr range from 22.9 to 3400 μg/g, whereas Ni ranges from 700 to 1800 μg/g. All of these geochemical characteristics indicate the input of the mantle material in the formation of serpentinite-related nephrite. CONCLUSIONS Geochemical characteristics of serpentinite-related and dolomite-related nephrite are different, which are related to the geological environment. For example, the composition of dolomite-related nephrite is controlled by the granite and dolomite marble, whereas the composition of serpentinite-related green nephrite is related to the mantle material and metamorphic fluids.

System nodes need to be renumbered manually when upgrading and reforming distribution network makes network topology change． Because optimization method is inapplicable to the network change，an improved forward and backward sweep algorithm is proposed which is unrelated to node label． In this paper，node type of sorts of distributed generation ( DG) in power flow calculation are induced and part of new node type of DG under improved control strategy are provided． The basis of DG as active constant node in certainty power flow calculation is analyzed． Based on improved back － forward sweep algorithm，general programs of power flow calculation in power distribution network of DG are programmed by MATLAB and the impact of DG on flow calculation to distribution network is analyzed quantitatively by plenty of simulation calculation of IEEE33 test system．

;The modified graphene/bacterial cellulose composite conductive fiber membranes were prepared by three different process which are vacuum filtration-solution reduction vacuum filtration-steam reduction and reduction-vacuum filtration. Structure and performance of prepared fiber membranes were characterized by scanning electron microscopy ( SEM) X-ray difraction ( XRD) and Raman spectroscopy. The effects of three kinds of membrane preparation processes on the surface resistance of the composite conductive fiber films were discussed. The effect of the three process on the surface resistance of the conductive fiber membranes were investigated. The results showed that PNIPAM-rGO was able to bond with bacterial cellulose ( BC) in vacuum filtration-solution reduction process and vacuum filtration-steam reduction process while the bonding effect was poor in reduction-vacuum filtration process. Besides XRD spectroscopy confirmed that the presence of PNIPAM-rGO almost did not affects the structure of crystalline region of BC Raman spectroscopy better confirmed that PNIPAM-GO can be fully reduced to PNIPAM-rGO. By comparing the surface resistance of the conductive fiber membranes it was found that the best conductivity was achieved by the membrane making-vapor reduction method. [ABSTRACT FROM AUTHOR]

Based on field research at port mineral yard, leaching of heavy metals as an important port soil, water pollution cannot be ignored. The rules of typical pollutants were simulated by the micro-universe model. In this study, the soil and water samples from 7 heavy metals storage yards of Tianjin Port have been investigated, revealing high Cd pollution in soil. Aquatic microcosm was used to simulate the chemical behavior of lead and cadmium in Tianjin port, and the internal transportation law was found by using the fugacity-based multimedia environmental mathematical model. The results of the model and experiment were consistent, showing that this model is suitable. The results of the model suggest that 61% of the cadmium in the system was sunk into sediment, the rest flowing out with water, and 99% of the lead was sunk into sediment, showing that for cadmium and lead, settling was the main transport process in the aquatic environment, especially for lead. The impact of minerals stored in the open areas is significant, and should be stored in containers without any direct contact with rain. Also, the pollution channel should be kept closed.

Green technology innovation is the core driving force for the high-quality development of regional integration in the Yangtze River Delta, and the free flow of innovative elements represented by green technology across cities is the due meaning of the construction of ecological green integration in the Yangtze River Delta. Based on the inter-city green patent transfer data from 2001 to 2020, this study analyzed the characteristics of the spatial evolution of green technology diffusion in the Yangtze River Delta, and discussed the development degree of ecological green integration in the area from the three levels of overall development, green technology supply, and green technology sales. This study found that the core area of the Yangtze River Delta urban agglomeration, consisting of the Shanghai-Suzhou-Wuxi-Changzhou- Zhenjiang-Nanjing urban belt and the Hangzhou Bay city agglomeration, is the core supporting space whether in terms of the intra-region green technology flow or inter-region green technology flow. Beijing-Tianjin area and the Pearl River Delta are not only the main external purchasers, but also the main external suppliers of green technologies in the Yangtze River Delta. The ecological green integration of the Yangtze River Delta under the inter-city green technology flow has been realized at the overall level and the green technology sales level, but it has rapidly declined in the green technology supply chain. [ABSTRACT FROM AUTHOR]

To investigate the influence of microreactor on the synthesis of nano-combustion catalysis, the nano copper 2,4-dihyoxybenzoicacid catalysis were synthesized with Cu/NO3)2, and 2,4-dihyoxybenzoicacid as primary substances by using as star-type microreactor. The obtained samples were characterized by laser size analysis (LSA), X-ray diffraction (XRD), N2, adsorption-desorption, scanning electronic microscophy (SEM), and thermogravimetric analysis(TG). The effects of the preparation conditions on the average particle size, crystal type. SBET and morphology of the catalysts were also studied. The results show that the morphology of the catalyst presents a regular-shaped sheet when the preparation conditions are at room temperature, and the better velocity of flow of the microreactors is 1mL/min, and the mixed time is 15 min. The catalyst sheet with a size of 100nm and a specific surface area of 21.626 m²/g was obtained. The DSC results showed that the copper 2,4,dihydroxybenzoate- 15 with the mixing timeof 15 min reduced the peak temperature decomposition of RDX from 242.3 °C to 239.1°C, which indicates that the catalyst exhibits better catalytic efficiency for thermal decomposition of RDX. [ABSTRACT FROM AUTHOR]

In view of the modal aliasing phenomenon that occurs when EMD is used to deal with the vibration signals of hydropower units which are coupled by multiple signals and noise, a fault signal preprocessing method is proposed based on differential empirical mode decomposition and energy characteristics.The signal is decomposed by differential empirical mode algorithm and then the energy matrix of each order differential signal is constructed. The simulation results show that the differential empirical mode decomposition can effectively avoid the mode mixing effect. The support vector machine is used to verify that the identification accuracy can reach 98% in the preprocessing of the guide bearing signal of the hydropower unit. This method has a good engineering application value in the application of complex coupling signal pretreatment of hydroelectric units. [ABSTRACT FROM AUTHOR]

This paper introduced main information technology to support virtual simulation experimental teaching and made a generalization about the types and feature and practice cases of virtual simulation experimental teaching of overseas universities, analyzed, development trends of promoting experimental teaching reform based on information technology and point out noteworthy new trends. [ABSTRACT FROM AUTHOR]

Torenia biniflora is a member of Scrophulariaceae Torenia , and it is an annual flowering plant that widely grows in Chinese subtropical area, such as Guangdong Province and Guangxi Zhuang Autonomous Region. T. biniflora is a wild flower with high great ornamental value. However, in natural growth condition, the reproduction speed of T. Biniflora is slow, proliferation rate is low, and the kinds of flower colour and type are few, therefore, it is unable to meet the diversified need of market. Plant tissue culture technology provides a new way to improve and breed new varieties for ornamental plants. Up to now, a lot of members of Torenia plants have been successfully established in vitro regeration system through tissue culture, such as T. fournieri Linden, T. baillonii Susie Wong and T. concolor Lindl. ,etc. While,tissue culture for T. Biniflora has never been reported. The main objective of this research was to establish in vitro regeneration system of T. Biniflora through tissue culture and study the effects of plant growth substances such as IBA, 6-BA and NAA for clonal multiplication. In this study, we created a reliable protocol for regenerating T. biniflora plants in tissue culture by using leaf explants. The effects of different concentrations and combinations of plant growth substances on adventitious bud induction and growth were studied, and the effects of different ionic strengths of media and concentrations of IBA on rooting were analyzed. According to a series of indices, such as average number of buds, frequency of bud induction, frequency of rooting, average number of root and average length of root, the optimal media for inducing adventitious buds and rooting were screened respectively. The results showed that adventitious bud induction was related with the concentrations and combinations of plant growth regulator, and the optimal medium for buds induction was MS+ 6-BA 0.5 mg • L-1 + NAA 0.2 mg • L-1. The best medium for rooting was 1/2 MS as basal medium with IBA 0.05 mg • L-1. In this study the in vitro plant reproductive system of T. biniflora with high frequence was completely established, and it would provide an important experiment foundation for the research of rapid propagation and genetic transformation for T. biniflora. [ABSTRACT FROM AUTHOR]

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This paper proposed an improved coupled simulated annealing (CSA) algorithm to optimize the hyper-parameters of least squares support vector machine (LS-SVM) . First, the CSA algorithm handled multiple independent parallel simulated annealing (SA) optimization process, which improved the optimization efficiency for hyper-parameters of LS-SVM model. Second, the acceptance temperature controlled the variance of the acceptance temperature which reduced the influence of the CSA algorithm to initialization parameters. Finally, it established CSA LS-SVM regression model to predict wheel tread wear based on the field data. The simulation results show that the proposed CSA LS-SVM regression model can trade off the model fit versus the model complexity, and the proposed model is effective for the wheel tread wear prediction. [ABSTRACT FROM AUTHOR]

As a new generation video coding standard, High Efficiency Video Coding (HEVC) achieves higher compression efficiency, but also requires a large amount of calculation. The parallel HEVC encoding algorithm is important to improve the encoding speed, therefore the design of parallel coding algorithm suitable for multi-core processors is of great significance to meet the requirements of High Density (HD) video real-time transmission and large-scale sharing. In this paper, a parallel entropy-coding framework based on Syntax-level grouping and multi-thread processing is presented. Firstly, the coding messages of a Coding Tree Unit(CTU) in HEVC are grouped according to the syntax elements; secondly, the parallel encoder based on Syntax-level is built according to the correlation between the data blocks; finally, frame-level parallel coding in HEVC is achieved by combining with the multi-threaded calculation. Experimental results show that the encoding speed of the proposed solution is 65% ~70% faster than that of the traditional serial architecture, meanwhile the video quality doesn't lose much. [ABSTRACT FROM AUTHOR]

Absorption ability of nine flue-cured tobacco varieties to six heavy metals of Cu, Pb, Cd, Cr, As and Hg was studied. The results showed that flue-cured tobacco varieties differed greatly in the absorption ability to the six heavy metals. Heavy metals could be divided into three categories according to the absorption ability of flue-cured tobacco varieties to the six heavy metals. The first class, Cd, was enriched strongly by flue-cured tobacco varieties, the average enrichment factor was 3. 751. The second class, Hg, was enriched as a medium level by flue-cured tobacco varieties, the average enrichment factor was 0. 735. The third class, including Cu, Pb, As and Cr, was enriched weakly, the average enrichment factor was 0. 066. [ABSTRACT FROM AUTHOR]

To understand the yellow - seed rape collected from Tibet China, variable coefficient and diversity index of 30 phenotypic characteristics of 16 Brassica rapa lines were investigated. Results indicated that except 3 traits ( petiole length, attaching pattern of stem - leaf and branching habits ), the average diversity index of the other 27 phenotypic characteristics was 1. 840, which was higher than 1. 709 as the rest of China. The variation coefficient (3. 92% to 52. 84%) also showed higher diversities. Based on principal component analysis, the ward method cluster analysis was chosen for establishing core collection and the Chi - square average distance was 0. 80. These 16 different yellow - seed lines were divided into 3 groups: Group I the longest pod - length and the most seed numbers per pod; Group II the highest branch height, the most primary branches and effective pod numbers; Group M the lowest branch height, the shortest effective blot length and the least effective pod numbers. In addition, the seed sizes of these yellow - seed materials were extremely large, and the colors of seed coat were rich [ABSTRACT FROM AUTHOR]

Aiming at radial distribution network topology features' an advanced forward and backward sweep algorithm is proposed based on the traditional one. Using the characteristics of non-leaf node acted as an end node of the branch' we determine the power and voltage calculation order before power flow calculation by searching leaf nodes and new leaf nodes repeatedly. Nodes can be numbered randomly and branches need no layering. The calculation process is simple and intuitive which could be applied in any radial distribution network flow calculation. Analysising the calculation of the example by MATLAB' the result shows that the proposed method is feasible and effective. [ABSTRACT FROM AUTHOR]

Cell cultivation is an important approach in the process of life science research. It is widely used in Genetic Engineering, Cell Engineering, Stem Cell Research and other fields of life science. Undergraduate students maa'oring in life science should systematically master the basic principles and methods of cell cultivation. To help the students understanding the basic knowledge and mastering the technique of cell cultivation, we initiated into the curriculum for undergraduates the course of Animal Cell Cultivation Experiment as a compulsory course. This course includes primary culture; subculture; determination of cell viability; infection of drugs on the growth of cell etc. On the teaching method, we pay more aatention to arouse the students' interest of learning, tamp their basic experimental skiils, and cultivate the innovation ability for them. It is intended to help them mastering the theory and practice of cell cultivation. So far the result of the introduction of the new course has been satisfactory : It has worked well in improving the students ' research ability and helping them to develop scientific ways of thinking. Their capability of analyzing and solving problems seems to have been somewhat enhanced. This wiil, no doubt, upgrade their comprehensive quality. In all, the reform has achieved good effect. [ABSTRACT FROM AUTHOR]

Acyl -CoA: diacylglycerol acyltransferase (DGAT) is the only key enzyme evolved in the Kennedy pathway and catalyzes the last step. This paper summrized the features of DGAT1 (subtype 1 of DGAT family) in eukaryote, including construction, substrate specificity, and spatio - temporal expressions. It especially reviewed DGAT1 function on plant growth and development. In discussion, some suggestions were made for further study of DGAT1 in plant. [ABSTRACT FROM AUTHOR]