和田师专学生档案管理系统的设计与实现

该文以和田师专学生档案管理为研究背景,结合学生档案管理系统的设计与实现,研究了基于分布式应用系统原理、设计和实现的问题。全国各大专院校及一些中专和中学的校园网建设已进入蓬勃发展的阶段。校园网建成以后,需要在校园网上建设一个全校范围的、开放的、分布的学生档案管理系统。文中论述了符合新疆特色的大专学校学生档案管理系统的一般构成,论述了校园网络与学生档案管理系统的关系。     

Effects of lead (Pb)-induced oxidative stress on morphological and physio-biochemical properties of rice

In rice, high concentration of lead (Pb) can cause phyto-toxicity affecting several physiological functions. Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils. In the current study, we evaluated four different rice cultivars for their response to Pb-induced stress. Three japonica type cultivars X-Jigna, Ediget, and Furat, and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations (0 mM, 0.6 mM, and 1.2 mM). The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation. Thereafter, four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity. The data revealed that a highest concentration of Pb (1.2 mM) induced significant reduction in agronomic traits such as plant height, number of tillers per plant, number of panicles per plant, and number of spikelets per panicle in all the rice cultivars. However, least reduction in the agronomic traits was observed in X-Jigna, whereas the highest reduction in the agronomic traits was observed in Ediget. Antioxidant activity of catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), and superoxide dismutase (SOD), was evaluated along with the accumulation of superoxide ions (O₂^.-), protein, proline, chlorophyll, sucrose, glucose, and fructose contents in all the rice cultivars. A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress. On the other hand, non-significant and slightly significant increase in the antioxidant activity, less accumulation of proline and sucrose contents, and higher reduction in the chlorophyll and protein contents was observed in Ediget, which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress. In addition, the other rice cultivars Furat and Amber 33, were found to be moderately tolerant to Pb-induced oxidative stress. In summary, our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems, leading to a balanced redox status in rice.

     

Development and antibacterial performance of silver nanoparticles incorporated polydopamine–polyester-knitted fabric

Metallization is one of the finishing processes in textile treatment that can produce multifunctional effects. The present study dealt with the development of an antibacterial polyester-knitted fabric via facile and green impregnation of silver nanoparticles (SNPs). This was done by applying a polymeric foundation on the polyester-knitted fabric by simply dip-coating in the aqueous solution of dopamine. Then the SNPs were in situ fabricated and impregnated on the surface of polydopamine-modified polyester-knitted fabric in an aqueous solution of AgNO₃ at room temperature. Thus, a multi-functional finishing of polyester-knitted fabric was done. The Fourier transform infrared spectroscopy was done to confirm the polymer attachment. Scanning electron microscopy equipped with energy dispersive X-ray was done to confirm the presence of SNPs on treated fabric. The crystallography of the treated surface was examined by X-ray diffraction. The antibacterial properties of treated fabrics against broad spectrum bacterial strains were investigated and found significant.     

POLYPHENOL OXIDASE FROM BARHEE AND ZAHDI DATES. I. PURIFICATION

Barhee and Zahdi dates (Phoenix dactylifera) contain polyphenol oxidase (PPO) at all maturity stages. The highest PPO activity is present in the medium green and late yellow stages of Barhee and Zahdi dates, respectively. The extracts of medium green stage of Barhee dates contained proteolytic activity. Four PPO forms were purified to homogeneity by acetone precipitation and DEAE-cellulose chromatography. The total fold purification was 8.0, 10.0, 12.5, and 15.0 with 6.7, 0.7, 2.2, and 2.7% recovery of PPO activity. A single PPO form was observed when 1.0mM of phenylmethylsulfonyl chloride (PMSC) was used in extraction solutions. However, only a single PPO form was observed in Zahdi dates and purified 13.1 fold with 7.7% recovery of activity .     

Characterization of milk coagulating properties from the extract of Withania coagulans

Plant aspartic proteinases (APs) from Withania coagulans were extracted by using NaCl (0.85%) and were characterized by pH, temperature stability, rennet strength and CaCl₂ supplementation. Additionally, the milk-clotting enzyme was partially purified by fractional precipitation with ammonium sulphate and acetone followed by column chromatography of the most active fraction, giving specific activity of 12 307.6 U/mg. The maximum enzyme activity was observed at 4.25 pH and 37°C, which suggested its use in making cheese requiring moderate temperatures (Mozerella, Cheddar). The enzymatic activity increases as the concentration of CaCl₂ increases and decreases with the increase of temperature. SDS analysis showed the presence of a single unique band having a molecular weight of 66 KDa.     

Anti-inflammatory and antioxidant potential capacities of AD-MSCs and BM-MSCs in suppressing pancreatic β-cells auto-immunity and apoptosis in rats with T1DM induced model

Since Type 1 diabetes (T1DM) occurs when β-cells mass is reduced to less than 20% of the normal level due to autoimmune destruction of cells resulting in the inability to secrete insulin, preservation or replenishment of the functional β-cells mass has become a major therapeutic focus for this diabetic type treatment. Thus, this 4-week work plan was designed to determine which mesenchymal stem cells (MSCs) type is more appropriate to alleviate pancreatic hazards resulting from diabetes induction; via tracking a comparative study between MSCs derived from adipose tissue (AD-MSCs) and from bone marrow (BM-MSCs) in management of T1DM considering their immunomodulatory, anti-apoptotic and antioxidative roles. Rats were divided randomly into 4 groups; control, STZ-diabetic (D), D+AD-MSCs, and D+BM-MSCs groups. Both stem cells types in this study were allogenic. Herein, both oxidative stress and antioxidant markers were evaluated using colorimetric analysis, while inflammatory, immune and apoptotic markers were assessed through flow cytometric analysis. Results showed that diabetic rats treated with either AD-MSCs or BM-MSCs exhibited marked pancreatic antioxidant and anti-inflammatory activities that were able to initiate pancreatic immunomodulation and reducing β-cells apoptotic death, thus, help to restore their normal insulin secretion and hypoglycemic abilities. However, AD-MSCs injection was shown to be superior as a pancreatic regenerative tool in overcoming diabetes; owing to their marked antioxidant, anti-inflammatory, immunomodulatory, and anti-apoptotic characteristics over BM-MSCs treatment.     

A TABOO SEARCH BASED APPROACH TO FIND THE PARETO OPTIMAL SET IN MULTIPLE OBJECTIVE OPTIMIZATION

Taboo search is a heuristic optimization technique which works with a neighbourhood of solutions to optimize a given objective function. It is generally applied to single objective optimization problems. Taboo search has the potential for solving multiple objective optimization (MOO) problems, because it works with more than one solution at a time, and this gives it the opportunity to evaluate multiple objective functions simultaneously. In this paper, a taboo search based algorithm is developed to find Pareto optimal solutions in multiple objective optimization problems. The developed algorithm has been tested with a number of problems and compared with other techniques. Results obtained from this work have proved that a taboo search based algorithm can find Pareto optimal solutions in MOO effectively.     

POLYPHENOL OXIDASE FROM BARHEE AND ZAHDI DATES. II. CHARACTERIZATION

Purified polyphenol oxidase (PPO) from Barhee and Zahdi date cultivars had a molecular weight of 17,500 and 17,000, respectively, as determined by exclusion gel chromatography. The enzyme possessed activity on o-diphenols but not on monophenols or m-diphenols. The highest activity was on catechol with K_m of 3.5 and 8.75 mM for PPO from Barhee and Zahdi dates, respectively. PPO from the two cultivars showed optimal pH for activity and stability around 6.0 and 7.0, respectively. The enzyme was completely inactivated when incubated at 70°C for 10 min. Activation energy for conversion of substrate to product was 3400 and 3600 cal/mole for PPO from Barhee and Zahdi dates, respectively. However, the activation energy for denaturation was 28000 and 27000 cal/mole for the enzyme from Barhee and Zahdi cultivars, respectively. Ascorbic acid, oxalic acid and sodium metabisulfite caused non-competitive inhibition for PPO activity, while sodium chloride was an uncompetitive inhibitor. Sodium metabisulfite was the most potent inhibitor with Ki values of 0.025 and 0.030 mM for PPO from Barhee and Zahdi dates, respectively.     

苏丹中部半干旱地区含水层特征的评价

苏丹中部的北杰济拉(Gezira)省的含水层为杰济拉含水层和白垩系含水层.在确定含水层水文地质参数的基础上,绘制了地下水水位等值线图,并通过矿化度的空间分布对地下水的化学特性进行评价.对水文地质参数的计算采用了雅各布方法和泰斯恢复水位法,通过对地下水中主要化学成分的分析来评价地下水水质,并绘制有关的水化学特性图.测得杰济拉含水层的平均导水系数和渗透系数分别为368 7m2/d和34 03m/d,均小于白垩系含水层的407 2m2/d和43 17m/d.杰济拉含水层物理化学成分的浓度明显高于白垩系含水层.白垩系含水层水质较好,适宜用作生活用水及饮用水.     

NUMERICAL SIMULATION OF GROUNDWATER DYNAMICS FOR SONGHUAJIANG RIVER VALLEY IN CHINA

The study area was designed and constructed,based on the simplification of a conceptual model, to develop a three-dimensional groundwater flow model for simulation of two-layers system. Finite difference groundwater flow model was constructed for the Central Songhuajiang River alluvial plain in Northeast China, with the coverage of 786. 6km^2. The grid networks with a spacing of 474. 4m by 509. 5m were used to cover the model area. The trial-and-error technique was used to calibrate the model. The sensitivity of the simulations to the model parameters was studied and the most sensitive parameters that controlling the residual heads distribution in the Songhuajiang River valley were defined.