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Identification of odorous compounds in reclaimed water using FPA combined with sensory GC-MS

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Journal of Environmental Sciences 2011年第10期23卷 1600-1604页

作者： Zhiming yan yu zhang Jianwei yu Hongying yuan Min yang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China.

Odorous compounds in the influent of a reclaimed water treatment plant （RWTP）, consisting of coagulation, sedimentation, continuous micro-filtration （CMF）, and chlorination in succession, in a north China city, were identified by combining flavor profile analysis （FPA） with sensory gas chromatograph-mass spectrometry （GC-MS）. The sewery/swampy/septic odor with an odor intensity of 6.4 was found to be the major odor group in the RWTP influent, and the existence of well-known odorant including dimethyl disulfide, dimethyl trisulfide, indole and skatole were confirmed using GC-MS. The result of a spiking test showed that the intensity （3.6） of the sewery/swampy/septic odor caused by these four chemicals contributed to over 50% of the odor intensity of the influent. The FPA intensity for sewery/swampy/septic odor in the RWTP effluent was 3.8, showing that the treatment process was not efficient for the removal of odorants, particularly indole and skatole.

关键词： sewery/swampy/septic odor reclaimed wastewater flavor profile analysis sensory-GC-MS analysis

Fusion Wheat Histone H4 Protein Increases Transfection Efficiency of Non-viral DNA Vector

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Chemical Research in Chinese Universities 2011年第2期27卷 264-268页

作者： WANG Chun-yan zhang yu-jing College of Animal Science and Veterinary Medicine Jilin University Changehun 130062 P. R. China

The lack of efficient and non-toxic gene delivery, preferably with non-viral DNA vectors, is generally regarded as a major limitation for gene therapy. In this study, a wheat histone H4 gene was cloned from Triticum aestivum, sequenced, modified and expressed in E. coli. The wheat histone H4 gene and reconstructed H4TL gene encoded wheat histone H4 and a recombinant protein of 141 amino acids with an approximate molecular weight of 15500. Gel electrophoresis mobility shift assays demonstrated that the purified protein had high affinity for DNA. Most significantly, the complex of plasmid pEGFP/C1 with H4TL was transfected with increased efficiency into MCF-7, HO8910, LNCap, A549 and HeLa cells in vitro. These results demonstrate that the targeting of non-viral vectors to tumor-specific receptors provides a cheap, simple and highly efficient tool for gene delivery.

关键词： Wheat histone H4 Non-viral gene delivery Histonefection

Effects of penehyclidine hydrochloride in small intestinal damage caused by limb ischemia-reperfusion

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World Journal of Gastroenterology 2011年第2期17卷 254-259页

作者： yan zhang yu-Fang Leng Xing Xue yue zhang Tao Wang yu-Qing Kang Department of Anesthesiology First HospitalLanzhou University Lanzhou 730000 Gansu Province China

AIM:To investigate the protective effect of penehyclidine hydrochloride post-conditioning in the damage to the barrier function of the small intestinal mucosa caused by limb ischemia-reperfusion(LIR) injury. METHODS:Male Wistar rats were randomly divided into three groups(36 rats each) :the sham-operation group(group S) ,lower limb ischemia-reperfusion group(group LIR) ,and penehyclidine hydrochloride postconditioning group(group PHC) .Each group was divided into subgroups(n=6 in each group) according to ischemic-reperfusion time,*** 0 h(T1) ,1 h(T2) ,3 h(T3) ,6 h(T4) ,12 h(T5) ,and 24 h(T6) .Bilateral hind-limb ischemia was induced by rubber band application proximal to the level of the greater trochanter for 3 *** group PHC,0.15 mg/kg of penehyclidine hydrochloride was injected into the tail vein immediately after 3 h of bilateral hind-limb *** designated rats were sacrificed at different time-points of reperfusion;diamine oxidase(DAO) ,superoxide dismutase(SOD) activity,myeloperoxidase(MPO) of small intestinal tissue,plasma endotoxin,DAO,tumor necrosis factor-α(TNF-α) ,and interleukin(IL) -10 in serum were detected in the rats. RESULTS:The pathological changes in the small intestine were observed under light *** levels of MPO,endotoxin,serum DAO,and IL-10 at T1-T6,and TNF-αlevel at T1-T4 increased in groups LIR and PHC(P<0.05) compared with those in group S,but tissue DAO and SOD activity at T1-T6 decreased(P<0.05) .In group PHC,the tissue DAO and SOD activity at T2-T6,and IL-10 at T2-T5 increased to higher levels than those in group LIR(P<0.05) ;however,the levels of MPO,endotoxin,and DAO in the blood at T2-T6,and TNF-αat T2 and T4 decreased(P<0.05) . CONCLUSION:Penehyclidine hydrochloride post-conditioning may reduce the permeability of the small intestines after *** protection mechanisms may be related to inhibiting oxygen free radicals and inflammatory cytokines for organ damage.

关键词： Penehyelidine hydrochloride Post-conditioning Limb ischemia-reperfusion injury Small intestine Protection

Therapeutic endoscopic retrograde cholangiopancreatography in a patient with asplenia-type heterotaxy syndrome:A case report

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World Journal of Gastrointestinal Surgery 2024年第11期16卷 3578-3583页

作者： yu-yan zhang Jiang Ruan yan Fu Department of Gastroenterology The Second Affiliated Hospital of Kunming Medical UniversityKunming 650101Yunnan ProvinceChina

BACKGROUND Asplenia-type heterotaxy syndrome(HS)is rare and refers to visceral malposition and *** is associated with a high infant mortality rate due to cardiac anomalies,and related digestive endoscopic interventions are poorly *** the improved long-term prognosis of these individuals after modern cardiac surgery,intra-abdominal anomalies have become increasingly *** SUMMARY Herein,we report successful endoscopic retrograde cholangiopancreatography(ERCP)in a 14-year-old male with asplenia-type HS that involved unique imaging findings and technical *** anatomic anomalies included complex congenital heart disease,midline liver placement,an absent spleen,a left-sided inferior vena cava,and dextroposition of the stomach and *** suffered from choledocholithiasis with obstructive jaundice,and the stone was successfully extracted with a basket following endoscopic papillary balloon *** Although anatomic anomalies in HS increase the degree of technical difficulty when performing ERCP,they can be safely managed by experienced endosco-pists,as illustrated by the present *** these variations with imaging modalities and being aware of them before initiating an invasive intervention are crucial to preventing potential complications.

关键词： Heterotaxy Asplenia Situs ambiguous Endoscopic retrograde cholangiopan-creatography Case report

Sensor/Actuator Faults Detection for Networked Control Systems via Predictive Control

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International Journal of Automation and computing 2013年第3期10卷 173-180页

作者： yu-yan zhang Jun-Ling zhang Xiao-yuan Luo Xin-Ping Guan Institute of Electrical Engineering Yanshan University

Quantized fault detection for sensor/actuator faults of networked control systems （NCSs） with time delays both in the sensor-to-controller channel and controller-to-actuator channel is concerned in this paper. A fault model is set up based on the possible cases of sensor/atuator faults. Then, the model predictive control is used to compensate the time delay. When the sensors and actuators are healthy, an H stability criterion of the state predictive observer is obtained in terms of linear matrix inequality. A new threshold computational method that conforms to the actual situation is proposed. Then, the thresholds of the false alarm rate （FAR） and miss detection rate （MDR） are presented by using our proposed method, which are also compared with the ones given in the existin~ literatures. Finally, some numerical simulations are shown to demonstrate the effectiveness of the proposed method.

关键词： Networked control system fault detection false alarm rate (FAR) miss detection rate (MDR) predictive control.

Diffusion coefficients of natural gas in foamy oil systems under high pressures

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Petroleum Science 2015年第2期12卷 293-303页

作者： yan-yu zhang Xiao-Fei Sun Xue-Wei Duan Xing-Min Li College of Petroleum Engineering China University of Petroleum School of Geosciences China University of Petroleum The Department of Chemical and Petroleum Engineering University of Calgary Research Institute of Petroleum Exploration and Development PetroChina

The diffusion coefficient of natural gas in foamy oil is one of the key parameters to evaluate the feasibility of gas injection for enhanced oil recovery in foamy oil reservoirs. In this paper, a PVT cell was used to measure diffusion coefficients of natural gas in Venezuela foamy oil at high pressures, and a new method for deter- mining the diffusion coefficient in the foamy oil was de- veloped on the basis of experimental data. The effects of pressure and the types of the liquid phase on the diffusion coefficient of the natural gas were discussed. The results indicate that the diffusion coefficients of natural gas in foamy oil, saturated oil, and dead oil increase linearly with increasing pressure. The diffusion coefficient of natural gas in the foamy oil at 20 MPa was 2.93 times larger than that at 8.65 MPa. The diffusion coefficient of the natural gas in dead oil was 3.02 and 4.02 times than that of the natural gas in saturated oil and foamy oil when the pressure was 20 MPa. However, the gas content of foamy oil was 16.9 times higher than that of dead oil when the dissolution time and pressure were 20 MPa and 35.22 h, respectively.

关键词： Foamy oil Diffusion coefficient - Heavy oil Gas injection High pressure

Influence of education and working background on physicians' knowledge of secondary prevention guidelines for coronary heart disease: results from a survey in China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第3期13卷 231-238页

作者： yan-jun GONG Tao HONG Jie JIANG Rong-hui yu yan zhang Zhao-ping LIU Yong HUO Department of Cardiology Peking University First Hospital Beijing 100034 China

Background and objective： In clinical practice, the standard of secondary prevention for coronary heart disease （CHD） is quite disappointing in China. The physicians＇ shortage of knowledge of secondary prevention guidelines is thought to be a key factor contributing to the inadequate and delayed translation of guidelines into clinical practice. The purpose of this study is to investigate the influence of physicians＇ characteristics, including their educa- tion and work experience, on their knowledge of secondary prevention in China. Methods： A representative ques- tionnaire survey was made of physicians from cardiology departments in 35 tertiary hospitals in China. The survey contained 19 questions on knowledge of guideline recommendations for the secondary prevention of CHD. We col- lected basic information about the physicians, including their educational degree, clinical practice duration/work experience and geographic region. Results： In total, 864 physicians participated in the survey. Eight hundred and thirty-seven completed questionnaires were analyzed. For 6 of the 19 questions, physicians with a postgraduate degree were more likely to answer correctly than those without such a degree. For 11 of the 19 questions, physicians with more than three years＇ clinical experience were more likely to answer correctly than those who had less than three years＇ experience. For 5 of the 19 questions, *** eastern areas were more likely to answer correctly than those from mid/western areas. The mean total score of correct answers to the questionnaire was 11.69 points. Edu- cational degree and clinical practice duration affected total scores significantly while practice location did not （β=0.500, P=0.004; ,β=0.979, P=0.000; and 8=0.228, P=0.162, respectively）. Even if a relatively low score of 12 is taken as a threshold level of acceptable knowledge （defined as a pass）, the pass rate of all physicians was only 53.9%. Educational degree and clinical practice durat

关键词： Coronary heart disease Secondary prevention Guidelines Survey

Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas

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World Journal of Gastroenterology 2011年第33期17卷 3850-3855页

作者： Dan Wang Xiao-Er Wei Lei yan yu-Zhen zhang Wen-Bin Li Institute of Diagnostic and Interventional Radiology The Sixth Affiliated People＇s HospitalShanghai Jiao Tong UniversityShanghai 200233China

AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were *** CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing software,including ***:Four males and two females were *** heterotopic pancreas sites were involved;three occurred in the stomach,including the gastric antrum(n =2)and lesser curvature(n=1),and two were in the duodenal *** one case of heterotopic pancreas lesion occurred in the *** cases had a solid yet soft tissue density that had a homogeneous pattern when viewed by enhanced ***,their CT values were similar to that of the *** ducts of the heterotopic pancreas tissue,one of the characteristic CT features of heterotopic pancreas tissue,were detected in the CT images of two *** images showed normal mucosa around the tissue,which is also an important indicator of a heterotopic ***,none of the CTVE images showed the typical signs of central dimpling or ***:CT,enhanced CT and CTVE techniques provide useful information about the location,growth pattern,vascularity,and condition of the gastrointestinal wall around heterotopic pancreatic tissue.

关键词： Heterotopic pancreas Computed tomography Contrast enhancement Computed tomography virtual endoscopy

Automatic Generation of Optimally Rigid Formations Using Decentralized Methods

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International Journal of Automation and computing 2010年第4期7卷 557-564页

作者： Rui Ren yu-yan zhang Xiao-yuan Luo Shao-Bao Li Academy of Armored Forces Engineering Beijing 100072 PRC Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 PRC

In this paper, decentralized methods of optimally rigid graphs generation for formation control are researched. The notion of optimally rigid graph is first defined in this paper to describe a special kind of rigid graphs. The optimally rigid graphs can be used to decrease the topology complexity of graphs while maintaining their shapes. To minimize the communication complexity of formations, we study the theory of optimally rigid formation generation. First, four important propositions are presented to demonstrate the feasibility of using a decentralized method to generate optimally rigid graphs. Then, a formation algorithm for multi-agent systems based on these propositions is proposed. At last, some simulation examples are given to show the efficiency of the proposed algorithm.

关键词： Optimally rigid graph infinitesimally rigid graph rigidity matrix multi-agent system formation