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Chemical Research in Chinese Universities 2006年第6期22卷 792-796页

作者： HU qiao-ling WU Jia CHEN Fu-ping SHEN Jia-cong Institute of Polymer Composites Zhejiang University Hangzhou 310027 P. R. China

This study focused on the preparation of magnetic chitusan nanocompesite that has a potential application to bone repair and regeneration using an in situ composite method where chitosan membrane was used as the template and NaOH was used as the precipitant. X-ray diffraction analysis results show the formation of magnetite in the chitosan matrix. From the magnetic measurement, it could be concluded that the magnetic chitosan rods were superparamagnetic,and that this is the unique property of nanomagnetite. Macroscopical layer structure of the magnetic chitosan rods was observed from the photographs after mechanical test, and the microlayer structure of the rods was observed from the images of scanning electron microscopy. The mechanism for preparing the rods was discussed in detail. Transmission electron microscope was used to investigate the magnetite particles in the chitosan matrix and from the images it was concluded that the magnetite particles dispersed well in chitosan matrix with particle size of about 10 nm. The mechanical properties of the magnetic chitosan rods were measured and the blending strength was found to be 98. 8 MPa. The mechanical properties did not decline when compared with those of the pure chitosan materials.

关键词： Chitosan Magnetite In situ compositing Red

High-Impact Bug Report Identification with Imbalanced Learning Strategies

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Journal of Computer Science & Technology 2017年第1期32卷 181-198页

作者： Xin-Li Yang David Lo Xin Xia qiao Huang Jian-ling Sun College of Computer Science and Technology Zhejiang University Hangzhou 310027 China School of Information Systems Singapore Management University Singapore Singapore

In practice, some bugs have more impact than others and thus deserve more immediate attention. Due to tight schedule and limited human resources, developers may not have enough time to inspect all bugs. Thus, they often concentrate on bugs that are highly impactful. In the literature, high-impact bugs are used to refer to the bugs which appear at unexpected time or locations and bring more unexpected effects （i.e., surprise bugs）, or break pre-existing functionalities and destroy the user experience （i.e., breakage bugs）. Unfortunately, identifying high-impact bugs from thousands of bug reports in a bug tracking system is not an easy feat. Thus, an automated technique that can identify high-impact bug reports can help developers to be aware of them early, rectify them quickly, and minimize the damages they cause. Considering that only a small proportion of bugs are high-impact bugs, the identification of high-impact bug reports is a difficult task. In this paper, we propose an approach to identify high-impact bug reports by leveraging imbalanced learning strategies. We investigate the effectiveness of various variants, each of which combines one particular imbalanced learning strategy and one particular classification algorithm. In particular, we choose four widely used strategies for dealing with imbalanced data and four state-of-the-art text classification algorithms to conduct experiments on four datasets from four different open source projects. We mainly perform an analytical study on two types of high-impact bugs, i.e., surprise bugs and breakage bugs. The results show that different variants have different performances, and the best performing variants SMOTE （synthetic minority over-sampling technique）＋ KNN （K-nearest neighbours） for surprise bug identification and RUS （random under-sampling）＋ NB （naive Bayes） for breakage bug identification outperform the Fl-scores of the two state-of-the-art approaches by Thung et al. and Garcia and Shihab.

关键词： high-impact bug imbalanced learning bug report identification

Preparation of Cassava Starch-based Superabsorbent Polymer Using a Twin-roll Mixer as Reactor

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Chinese Journal of Polymer Science 2014年第10期32卷 1348-1356页

作者： Dong-ling qiao Xian-yang Bao 刘宏生 Xing-xun Liu ling Chen 余龙 Xiao-qing Zhang Pei Chen Centre for Polymer from Renewable Resource ERCPSP SCUT CSIRO Materials Science and Engineering Clayton Vic 3169 Australia School of Food Science South China Agriculture University

Cassava starch-based superabsorbent polymer was successfully synthesized using a new technology that based on modification of a Haake twin-roll mixer as reactor. The cassava starch was first gelatinized then modified by grafting under external shear stress in the reactor. The torque and temperature curves as a function of time can reflect the variations in the reactor and also offer some information about the copolymerization reaction. The advantages of this system include starch modification can be carried out （l） with high starch concentration, （2） under controlled ticne and （3） smaller amount of sample （60 g） required. The technology provides useful guides for reactive extrusion. The starch grafted composites were characterized by Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （NMR） and thermal gravimetric analysis （TGA）. The TGA was also used for determining the percentage of grafting ratio. The results show that the cassava starch has been successfully grafted with acrylamide then crosslinked by N,N＇-methylene-bisacrylamide using this reactor. The ultimate water absorbent capacity of the cassava-based superabsorbent polymer impacted by various pH values illustrated that the acid and basic solutions inhibit the ability of imbibing water. Additionally, gel properties of the cassava-based superabsorbent polymer were investigated. It can be concluded that the structure of cassava gel is stable, while the three dimensional network of cassava-based superabsorbent polymer is rigid but its structure could not resist external force effectively and everlastingly since G＇ was decreased with increasing amplitude.

关键词： Graft Acrylamide Superabsorbent Extrusion Starch Cassava.

Hypoxia tolerance in fish depends on catabolic preference between lipids and carbohydrates

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Zoological Research 2023年第5期44卷 954-966页

作者： Qiang Ma Yuan Luo Jia Zhong Samwel Mchele Limbu ling-Yu Li Li-qiao Chen Fang qiao Mei-ling Zhang Qiang Lin Zhen-Yu Du LANEH School of Life SciencesEast China Normal UniversityShanghai 200241China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdaoShandong 266071China CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouGuangdong 510301China School of Aquatic Sciences and Fisheries Technology University of Dar es SalaamDar es Salaam 60091Tanzania

Hypoxia is a common environmental stress factor in aquatic organisms,which varies among fish ***,the mechanisms underlying the ability of fish species to tolerate hypoxia are not well ***,we showed that hypoxia response in different fish species was affected by lipid catabolism and preference for lipid or carbohydrate energy *** of biochemical lipid catabolism through peroxisome proliferator-activated receptor alpha(Pparα)or increasing mitochondrial fat oxidation in tilapia decreased tolerance to acute hypoxia by increasing oxygen consumption and oxidative damage and reducing carbohydrate catabolism as an energy ***,lipid catabolism inhibition by suppressing entry of lipids into mitochondria in tilapia or individually knocking out three key genes of lipid catabolism in zebrafish increased tolerance to acute hypoxia by decreasing oxygen consumption and oxidative damage and promoting carbohydrate ***,anaerobic glycolysis suppression eliminated lipid catabolism inhibition-promoted hypoxia tolerance in adipose triglyceride lipase(atgl)mutant *** 14 fish species with different trophic levels and taxonomic status,the fish preferentially using lipids for energy were more intolerant to acute hypoxia than those preferentially using *** study shows that hypoxia tolerance in fish depends on catabolic preference for lipids or carbohydrates,which can be modified by regulating lipid catabolism.

关键词： Hypoxia tolerance Catabolic preference Lipid Carbohydrate Oxidative damage

Phase change analysis of an underwater glider propelled by the ocean's thermal energy

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Journal of Marine Science and Application 2007年第4期6卷 37-43页

作者： KONG qiao-ling MA Jie State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Shanghai 200030 China

The phase change characteristic of the power source of an underwater glider propelled by the ocean＇s thermal energy is the key factor in glider attitude control. A numerical model has been established based on the enthalpy method to analyze the phase change heat transfer process under convective boundary conditions. Phase change is not an isothermal process, but one that occurs at a range of temperature. The total melting time of the material is very sensitive to the surrounding temperature. When the temperature of the surroundings decreases 8 degrees, the total melting time increases 1.8 times. But variations in surrounding temperature have little effect on the initial temperature of phase change, and the slope of the temperature time history curve remains the same. However, the temperature at which phase change is completed decreases significantly. Our research shows that the phase change process is also affected by container size, boundary conditions, and the power source＇s cross sectional area. Materials stored in 3 cylindrical containers with a diameter of 38ram needed the shortest phase change time. Our conclusions should be helpful in effective design of underwater glider power systems.

关键词： phase change heat transfer analysis ocean thermal energy underwater glider

Sodium 4-phenylbutyrate Attenuates High-fat Diet-induced Impaired Spermatogenesis

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Biomedical and Environmental Sciences 2018年第12期31卷 876-882页

作者： WANG Er Hui YAO San qiao TAO ling XI Jin Yan Department of Nutrition and Food Hygiene College of Public Health Xinxiang Medical University Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine Xinxiang Medical University

Objective To determine the mitigating effects of sodium 4-phenylbutyrate(4-PBA) on high-fat diet(HFD)-induced spermatogenesis dysfunction. Methods Male rats(n = 30) were randomly divided into three groups: control, HFD, and 4-PBA(HFD +4-PBA). After 13 weeks, rats were euthanized. Testes and epididymis were harvested for further analysis. Sex hormones were detected, and hematoxylin and eosin staining was performed to examine the histological changes in the testes. Semen samples were collected to evaluate sperm quality. Spermatogenic cell apoptosis was detected by TUNEL assay. Results Compared with the control group, the final body weight and body weight gain were significantly higher in HFD-fed rats, while the testicle/body weight ratios were lower(P < 0.05). In HFD-fed rats, obvious pathological changes in the testicular tissue were observed. Treatment with 4-PBA attenuated HFD-induced histological damage, ameliorated the HFD-induced decrease in serum testosterone(T), and reduced the rate of testicular cell apoptosis(P < 0.05) in obese male rats. Finally, 4-PBA significantly improved semen parameters in HFD rats(P < 0.05). Conclusion HFD exposure induced detrimental effects on spermatogenesis, semen quality, serum T level, and testicular cell apoptosis in rats. Treatment with 4-PBA ameliorated HFD-induced impaired spermatogenesis via inhibition of apoptosis in rats. 4-PBA may have therapeutic value in the treatment of obesity-related impairment of spermatogenesis.

关键词： Male infertility Sodium 4-phenylbutyrate Obesity Spermatogenesis Semen Testis

Present and future of hydrology

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Water Science and Engineering 2013年第3期6卷 241-249页

作者： Xiao-fang RUI Ning-ning LIU qiao-ling LI Xiao LIANG College of Hydrology and Water Resources Hohai University

The complexities of hydrological phenomena, the causes that lead to these complexities, and the essences and defects of reductionism are analyzed. The driving forces for the development of hydrology and the formation of branch subjects of hydrology are discussed. The theoretical basis and limitations of existing hydrology are summarized. Existing misunderstandings in the development of the watershed hydrological model are put forward. Finally, the necessity of the expansion of hydrology from linear to nonlinear is discussed.

关键词： hydrological phenomenon hydrological theory hydrological method hydrologicalmodel reductionism nonlinear

A facile approach to construct hybrid multi-shell calcium phosphate gene particles

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 292-297页

作者： Zhi-xue XU Ran ZHANG You-xiang WANG qiao-ling HU MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 31002 7 China

The calcium phosphate (CaP) particles have attracted much attention in gene therapy. How to construct stable gene particles was the determining factor. In this study,hybrid multi-shell CaP gene particles were successfully constructed. First,CaP nanoparticles served as a core and were coated with DNA for colloidal stabilization. The ξ-potential of DNA-coated CaP nanoparticles was -15 mV. Then polyethylenimine (PEI) was added and adsorbed outside of the DNA layer due to the electrostatic attraction. The ξ-potential of hybrid multi-shell CaP particles was slightly positive. With addition of PEI,the hybrid multi-shell particles could condense DNA effectively,which was de-termined by ethidium bromide (EtBr) exclusion assay. The hybrid particles were spherical and uniform with diameters of about 150 nm at proper conditions. By simple modification of PEI,the hybrid multi-shell CaP gene particles were successfully constructed. They may have great potential in gene therapy.

关键词： Calcium phosphate Polyethylenimine (PEI) Hybrid Gene

Polymorphisms in genes involved in folate metabolism as maternal risk factors for Down syndrome in China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第2期9卷 93-99页

作者： Shao-shuai WANG Fu-yuan qiao ling FENG Juan-juan LV Department of Obstetrics and Gynecology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496). The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.

关键词： Tetrahydrofllate dehydrogenase Ligases Down syndrome Folate

Numerical simulation of mechanical properties of straight pipe and elbow during in-service welding

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China Welding 2018年第4期27卷 33-40页

作者： qiao ling Han Tao College of Mechanical and Electronic Engineering China University of Petroleum

Elbows are the most vulnerable parts in pipeline network systems. The residual stress for in-service welding repair has significant impacts on the mechanical properties of straight pipes and elbows. In this paper,the thermal elastic-plastic finite element method is employed to investigate the mechanical field during the in-service welding. The prediction of residual stress and deformation in the straight pipe and elbow is performed based on the validation of the numerical models. And the effects of the curvature radius and defects on the elbow are investigated. The results show that the residual stress distribution is uneven along various directions after welding. And the mechanical properties of the elbow decrease when the curvature radius is small. Compared to the intact elbow,the residual stress of the elbow with defects concentrates in the defective area. The depth of defect is the main factors affecting the mechanical properties of the elbow. A systematic analysis of the mechanical properties of straight pipes and elbows is proposed to provide guidance to the in-service welding.

关键词： in-service welding elbow residual stress curvature radius pressure defects