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Development and application of a water pollution emergency response system for the Three Gorges Reservoir in the Yangtze River, China

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Journal of Environmental Sciences 2011年第4期23卷 595-600页

作者： Qiang He Shujuan Peng jun zhai Haiwen Xiao Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment Ministry of Education Chongqing University Chongqing 400045 China.

There are many watercraft and production accidents in the Three Gorges Reservoir Area （TGRA） of the Yangtze River in China every year. Accidents threaten the water quality of the 1085 km 2 surface area of the TGRA and millions of local people if oil and chemical leakage were to occur. A water pollution management system for emergency response （WPMS ER） was therefore designed for the management of pollution in this area. An integrated geographic information system （GIS）-based water pollution management information system for the TGRA, called WPMS ER TGRA, was developed in this study. ArcGIS engine was used as the system development platform, and Visual Basic as the programming language. The models for hydraulic and water quality simulation and the generation of body-fitted coordinates were developed and programmed as a dynamically linked library file using Visual Basic, and they can be launched by other computer programs. Subsequently, the GIS-based information system was applied to the emergency water pollution management of a shipwreck releasing 10 tons of phenol into the Yangtze River during two hours. The results showed that WPMS ER TGRA can assist with emergency water pollution management and simulate the transfer and diffusion of accidental pollutants in the river. Furthermore, it can quickly identify the affected area and how it will change over time within a few minutes of an accident occurring.

关键词： water pollution emergency emergency response management information system the Three Gorges Reservoir

Meta analysis on the relationship between gene polymorphisms of vascular endothelial growth factorand retinal prognosis risk of prematurity

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 397-400页

作者： jun zhai, Ying-Pu Sun Reproductive Center the First Affiliated Hospital of Zhengzhou University Zhengzhou 450052 Henan Province China Department of Gynaecology and Obstetrics People's Hospital of Zhengzhou Zhengzhou 450003 Henan Province China

AIM: To explore the relationship between gene polymorphisms of (VEGF) and retinopathy of prematurity (ROP). METHODS: Literature materials related to gene polymorphisms of VEGF and ROP in PubMed, EMBASE, Cochrane and CBM database were retrieved. These materials were screened according to inclusion and exclusion standards. Patients diagnosed with ROP in clinic were regarded as control group and ROP patients who were in treatment were regarded as observation group. The indexes in two groups were matched except birth weight (BW), gender and gestational weeks. Meta5.1 was used to analyze the relationship between gene polymorphisms of VEGF and ROP. RESULTS: Four random control tests (RCT) were included in this research, including 2611 patients. Met) analysis results showed that VEGF affected ROP, having statistical significance. The combined ratio was 0.44 (95% CI, 0.07, 0.80), 0.42 (95%CI, 0.09, 0.74) and 0.75 (95%CI, 0.02, 1.49), respectively. Carrying +405 allele might increase the premature infants risk of having ROP. CONCLUSION: ROP may be related to its carrying of +405 allele. Large-scale, multi-factor RCT researches are still needed in order to identify the relation between VEGF and ROP.

关键词： polymorphisms of vascular endothelial growth factor premature infant retinopathy Meta analysis

Output Feedback Tracking Control for a Class of Switched Nonlinear Systems with Time-varying Delay

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International Journal of Automation and computing 2014年第6期11卷 605-612页

作者： Bin Wang jun-Yong zhai Shu-Min Fei Key Laboratory of Measurement and Control of CSE Ministry of Education School of Automation Southeast University

This paper studies the problem of tracking control for a class of switched nonlinear systems with time-varying delay. Based on the average dwell-time and piecewise Lyapunov functional methods, a new exponential stability criterion is obtained for the switched nonlinear systems. The designed output feedback H∞controller can be obtained by solving a set of linear matrix inequalities(LMIs).Moreover, the proposed method does not need that a common Lyapunov function exists for the switched systems, and the switching signal just depends on time. A simulation example is provided to demonstrate the effectiveness of the proposed design scheme.

关键词： Tracking control switched nonlinear systems exponential stability time-varying delay H ∞ controller

Phytoremediation of levonorgestrel in aquatic environment by hydrophytes

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Journal of Environmental Sciences 2014年第9期26卷 1869-1873页

作者： Guo Li jun zhai Qiang He Yue Zhi Haiwen Xiao Jing Rong Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment Ministry of EducationChongqing University Department of Civil Engineering McGill UniversityMontrealQuebec H3A 0C3Canada

Adsorption and degradation of levonorgestrel （LNG） by two hydrophytes, Cyperus alternfolius （CA） and Eichhornia crassipes （EC）, were investigated under light-shielding conditions in the water column. Variations of LNG concentrations in water, plant root epidermis, root, stem and leaf of the plants were analyzed. The results indicated that the removal efficiency of LNG by hydrophytes over the period of 50 days was significantly greater than the blank control （p 〈 0.05）, with the removal rates of 79.80%± 3.10% and 78.86% ± 2.55% for CA and EC, respectively. Compared with bio-adsorption, bio-conversion of LNG was found to be the dominant elimination pathway, evidenced by relatively high conversion rates （77.31% ±2.68% for CA and 77.82% ± 2.95% for EC）, while the adsorption rates were lower （1.77% ± 0.90% for CA and 1.05% ± 0.40% for EC）. The bio-adsorption and conversion of LNG showed no significant differences between the two hydrophytes. Additionally, the mineralization on root epidermis played an important role in the reduction of LNG in water.

关键词： Phytoremediation Hydrophyte Levonorgestrel Hormone Degradation

The conservation patterns of grassland ecosystem in response to the forage-livestock balance in North China

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Journal of Geographical Sciences 2021年第4期31卷 518-534页

作者： HUANG Lin NING Jia ZHU Ping ZHENG Yuhan zhai jun Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Satellite Environment Center Ministry of Ecology and EnvironmentBeijing 100094China University of Chinese Academy of Sciences Beijing 100049China

Being a key ecological security barrier and production base for grassland animal husbandry in China,the balance between grassland forage supply and livestock-carrying pressure in North China directly affects grassland degradation and restoration,thereby impacting grassland ecosystem *** paper analyzes the spatiotemporal variation in grassland vegetation coverage,forage supply,and the balance between grassland forage supply and livestock-carrying pressure from 2000 to 2015 in North *** then discuss the spatial pattern of grassland ecological conservation under the impacts of grassland degradation and restoration,and livestock-carrying *** the last 16 years,the total grassland area in North China decreased by about 16,000 km^(2),with vegetation coverage degraded by 6.7%of the grasslands but significantly restored by another 5.4%of *** provisioning of forage by natural grassland mainly increased over time,with an annual growth rate of approximately 0.3 kg/ha,but livestock-carrying pressure also increased *** livestock-carrying pressure index without any supplementary feeding reached as high as *** from the potential livestock-carrying capacity in northeastern Inner Mongolia and the central Tibetan Plateau,most regions in North China are currently *** the actual supplementary feeding during the cold season,the livestock-carrying pressure index is about 3.1,with the livestock-carrying pressure mitigated in central and eastern Inner *** full supplementary feeding in the cold season,livestock-carrying pressure index will fall to 1.9,with the livestock-carrying pressure alleviated significantly in Inner Mongolia and on the Tibetan ***,we propose different conservation and development strategies to balance grassland ecological conservation and animal husbandry production in different regions of protected areas,pastoral areas,farming-pastoral ecotone,and farming areas,according

关键词： grassland degradation and restoration forage supply livestock-carrying pressure grassland ecosystem conservation North China

A cross-layer approach to enable multipacket transmission in MIMO-SDMA based WLAN

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 271-278页

作者： Sheng-bo CHEN Wei CHEN Wei-lan HUANG Li-jun zhai Xu-ming LIU Department of Electronic Engineering. Tsinghua University Beijing 100084 China Nokia Research Center Beijing 100176 China

We propose a medium access control(MAC) protocol for uplink transmissions in wireless local area networks(WLANs),where both stations and access points(APs) are equipped with multiple antennas. The protocol solves some common problems in utilizing multiple input multiple output(MIMO) under the 802.11 protocol,e.g.,how to deploy preamble(training sequence) used for channel estimation and how to enable simultaneous data transmissions,and facilitates two simultaneous uplink data transmissions via a cross-layer approach. Furthermore,we develop a 3D discrete-time Markov model to analyze the per-formance of the proposed WLAN scheme. The analytical results are verified by simulation,and numerical results show that the system throughput can be significantly improved by our proposed scheme as compared with conventional schemes.

关键词： Multiple input multiple output (MIMO) Medium access control (MAC) Cross-layer design

Complications of microvascular decompression in hemifacial spasm treatment Retrospective analysis of 156 cases

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Neural Regeneration Research 2008年第1期3卷 101-103页

作者： Yongfeng Sun Guanghui Dai jun yuan Weidong zhai Jianwei Zhong Tao Wang Department of Neurosurgery Beijing General Group Hospital the Chinese People＇s Armed Police Forces Beijing 100027 China

BACKGROUND： Microvascular decompression has become a well-accepted, safe method in the treatment of hemifacial spasms. However, postoperative complications exist and influence the prognosis of the disease. OBJECTIVE： This study aimed to analyze, by case review, the characteristics and regularity of microvascular decompression complications in the treatment of hemifacial spasm. DESIGN： Retrospective analysis. SETTING： Beijing General Group Hospital of the Chinese People＇s Armed Police Forces. PARTICIPANTS： A total of 156 patients with hemifacial spasm were admitted to the Department of Neurosurgery, Beijing General Group Hospital of the Chinese People＇s Armed Police Forces from june 2004 to june 2006 and recruited for this study. The patients, 57 males and 99 females, averaged 46 years of age （range 17-68-years old）. All suffered from facial innervated muscular paroxysmal and recurrent contraction, which could not be controlled by consciousness. Electromyogram demonstrated waves of fibrillation and fasciculation. Prior to admission, all patients had received other treatments. Written informed consents for treatment were obtained from all patients. This protocol was approved by the Hospital＇s Ethics Committee. METHODS： After anesthesia, a cranial bone pore was drilled below the connection of the lateral sinus and sigmoid sinus. Dura mater was dissected at the ＂⊥＂ shape and held in the air. Under microscopy, the flocculus cerebelli was lifted slightly up for convenient observation of the cerebellopontine angle. The mucous membrane was sharply separated. Corresponding vessels were identified at the root of the facial nerves and subsequently liberated and disassociated from the root exit zone. Suitably sized Teflon cotton was placed between the corresponding vessels and brain stem. MAIN OUTCOME MEASURES： Complications of microvascular decompression. RESULTS： All 156 patients participated in the final analysis. （1） Postoperatively, 66 （42%） patients presented with obvious

关键词： microvascular decompression hemifacial spasm postoperative complication

Vibrational chaotic dynamics in triatomic molecules： A comparative study

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Frontiers in Biology 2012年第5期7卷 514-520页

作者： Liang-jun zhai Yu-jun Zhen Shi-Liang Ding School of Physics Shandong UniversityJinan 250100China

Within Lie algebraic model, the vibrational chaotic dynamics in triatomic molecules are studied. The molecules of H2S, NO2, and O3 are sampled to explore the dynamical differences between the local and normal mode molecules. The comprehensive effects of the local and normal mode vibrations, resonances and chaos on the dynamical entanglement are studied. The results demonstrate that the resonances as well as chaos can promote the evolution of dynamical entanglement.

关键词： vibrational chaotic dynamics triatomic atomic U(4) algebraic model

Study of glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding

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World Journal of Gastroenterology 2009年第39期15卷 4945-4951页

作者： Yan-Mei Wang Liu-Fang Cheng Nan Li Kai Wu jun-Shan zhai Ya-Wen Wang Department of Gastroenterology the Second Affiliated Hospital of PLA General Hospital Beijing 100091 China

AIM:To investigate glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding and to evaluate the long-term efficacy and safety of this ***:A total of 148 cirrhotic patients in our hospital with esophagogastric variceal bleeding(EGVB) were included in this study.N-butyl-2-cyanoacrylate was mixed with lipiodol in a 1:1 ratio and injected as a bolus of 1-3 mL according to variceal *** underwent endoscopic follow-up the next week,fourth week,second month,fourth month,and seventh month after injection and then every 6 mo to determine the cast *** abdominal X-ray fi lm and ultrasound or computed tomographic scan were also carried out in order to evaluate the time of variceal disappearance and complete extrusion of the *** average follow-up time was 13.1 ***:The instantaneous hemostatic rate was 96.2%.Early re-bleeding after injection in 9 cases(6.2%) was estimated from rejection of *** re-bleeding occurred in 12 patients(8.1%) at 2-18 *** glue cast was extruded into the lumen within one month in 86.1% of patients and eliminated within one *** erosion was seen at the injection position and mucosa edema in the second *** glue casts were extruded in 18 patients(12.1%) after one week and in 64 patients(42.8%) after two *** kinds of glue clumping shapes and colors on endoscopic examination were observed in 127 patients(86.1%) within one month,including punctiform,globular,pillar and *** one patients(27.9%) had glue extrusion after 3 mo and 28 patients(28.9%) after six *** extrusion time was not related to the injection volume of *** was seen in 70.2%(104 cases) *** main complication was re-bleeding resulting from *** prognosis of the patients depended on the severity of the underlying liver ***:Endoscopic injection of cyanoacrylate is highly effective for gastric varices *** glue clump

关键词： Gastric variceal bleeding Glue extruded N-butyl-2-cyanoacrylate Portal hypertension