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Contribution of aboveground litter to soil respiration in Populus davidiana Dode plantations at different stand ages

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Journal of Mountain Science 2016年第6期13卷 1000-1012页

作者： ZHAO Xin li Fa-dong ZHANG Wan-jun AI Zhi-pin Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Agricultural Water Resources Hebei key Laboratory of Agricultural Water-saving Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 China

Soil respiration from decomposing aboveground litter is a major component of the terrestrial carbon cycle. However, variations in the contribution of aboveground litter to the total soil respiration for stands of varying ages are poorly understood. To assess soil respiration induced by aboveground litter, treatments of litter and no litter were applied to 5-, l0-, and 20-year-old stands of Populus davidiana Dode in the sandstorm source area of Beijing-Tianjin, equations were applied to China. Optimal nonlinear model the combined effects of soil temperature and soil water content on soil respiration. Results showed that the monthly average contribution of aboveground litter to total soil respiration were 18.46% ± 4.63%, 16.64% ± 9.31%, and 22.37% ± 8.17% for 5-, 10-, and ao-year-old stands, respectively. The relatively high contribution in 5- and 20-year-old stands could be attributed to easily decomposition products and high accumulated litter, resoectivelv. Also. it fluctuated monthly for all stand ages due to substrate availability caused by phenology and environmental factors. litter removal significantly decreased soil respiration and soil water content for all stand ages （P 〈 0.05） but not soil temperature （P 〉 0.05）. Variations of soil respiration could be explained by soil temperature at 5-cm depth using an exponential equation and by soil water content at lo-cm depth using a quadratic equation, whereas soil respiration was better modeled using the combined parameters of soil temperature and soil water content than with either soil temperature or soil water content alone. Temperature sensitivity （Q10） increased with stand age in both the litter and the no litter treatments. Considering the effects of aboveground litter, this study provides insights for predicting future soil carbon fluxes and for accurately assessing soil carbon budgets.

关键词： Aboveground litter Nonlinear equation Populus davidiana Dode Soil respiration Temperature sensitivity

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Clinical effect of methimazole combined with selenium in the treatment of toxic diffuse goiter in children

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World Journal of Clinical Cases 2022年第4期10卷 1190-1197页

作者： Xiao-Hong Zhang Gao-pin Yuan Ting-li Chen Department of Pediatric Endocrinology Quanzhou Women and Children’s HospitalQuanzhou 362000Fujian ProvinceChina

BACKGROUND The incidence of toxic diffuse goiter(Graves’disease)is higher in adolescents and preschool-aged children,with an upward *** incidence at 6–13 years of age is approximately 11.0%,and the incidences in men and women are 7.8%and 14.3%,*** To explore the clinical effect of methimazole combined with selenium in the treatment of toxic diffuse goiter(Graves’disease)in children and its effect on serum anti-thyroglobulin antibody(TRAb)and anti-thyroid peroxidase antibody(TPOAb).METHODS A total of 103 children with Graves’disease treated in our hospital from January 2018 to June 2021 were divided into a traditional group and a combined group(15-20 mg methimazole orally given to children)and a combined group(50μg selenium added on the basis of traditional treatment)according to different treatment methods to explore the therapeutic effects of the two methods and to observe the changes in thyroid volume and serum TRAb,TPOAb,free thyroxine(FT4)and inflammatory factor levels before and after *** time taken for FT4 to return to normal was compared between the two *** Treatment was significantly more effective in the combined group than in the traditional group(P<0.05).The thyroid volumes of the children in the two groups was measured before and after *** volume decreased significantly after treatment in both groups,and the thyroid volume was significantly lower in the combined group than in the traditional group(P<0.05).The serum levels of interleukin-6(IL-6),IL-8,TRAb,TPOAb and FT4 in the two groups were detected before and after *** levels of IL-6,IL-8,TRAb,TPOAb and FT4 were significantly lower in the combined group than in the traditional group(P<0.05).Follow-up of the children in the two groups showed that compared with the traditional group,it took less time for children in the combined group to return to the normal level(P<0.05).CONCLUSION Methimazole combined with selenium can effectively treat Gra

关键词： Methimazole Selenium Children Antithyroid globulin Anti-thyroid peroxidase antibody

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Produced-water treatment: Application and research of combined fiber coalescence technique in offshore oilfield

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Petroleum Science 2023年第1期20卷 569-576页

作者： pin-Yi Dai Yi-Qian liu Hao Lu Yu-Dong li Qiang Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai200237China

When the process of extraction of oil from an offshore oilfield enters the advanced stages,the water content in the extracted fluid can be above 90%.The water quality is complex with many types of pollutants and highly emulsified ***,a key consideration in the production process of offshore oilfields is the efficient and economical treatment of the oil-containing produced water to make it suitable for discharge and recover oil *** this study,we developed a hydrophilic and hydrophobic combined fiber coalescence separator with composite fiber shapes using fiber induction and X/*** separator is designed based on experimental observations of the mechanism of structure coalescence in the physical oil removal method.A pilot test was performed on an oil exploration platform in the Bohai *** the designed flow rate,the separator reduced the total concentration of petroleum in the produced water from 2000 to 3000 mg/L to below 60 mg/L,with an average oil removal efficiency of 98.24%.Furthermore,it effectively reduced the number of organic compounds present in the water from 120 to 17 and removed 70% of the *** test results show that the proposed device can be used fr produced-water treatment on offshore platforms.

关键词： Combined fiber coalescence Production water Oil-water separation X/U weaving

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Observation of the effect of angiojet to treat acute lower extremity arterial embolization

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World Journal of Clinical Cases 2023年第15期11卷 3491-3501页

作者： Xiao-Hu Meng Xu-pin Xie Yong-chang liu chang-pin Huang lin-Jun Wang Han-Yi liu Xin Fang Guo-Hui Zhang Department of Vascular Surgery The Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina Department of General Surgery The Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310022Zhejiang ProvinceChina Department of Vascular Surgery The Affiliated Hangzhou Cancer HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Through significant advances in the treatment of peripheral arterial occlusive disease,acute ischemia of the lower extremity is still associated with significant morbidity,limb threat and *** two main causes of acute ischemia in lower extremities are arterial embolism and atherosclerotic *** recognition and treatment of acute limb ischemia in emergency situations is essential in order to minimize the duration of *** To investigate the application effect of angiojet thrombolysis in the treatment of acute lower extremity arterial *** Sixty-two patients with acute lower extremity arterial embolization admitted to our hospital from May 2018 to May 2020 were *** them,the observation group(twenty-eight cases)had received angiojet thrombolysis,and the control group(thirty-four cases)had received femoral artery incision and *** thrombus clearance,significant residual stenosis of the lumen was combined with balloon dilation and/or stent *** the thrombus removal was not satisfactory,catheter-directed thrombolysis was *** incidence of postoperative complications,recurrence rate and recovery of the two groups were *** There were no significant differences in postoperative recurrence(target vessel reconstruction rate),anklebrachial index and the incidence of postoperative complications between the two groups(P>0.05);there were statistically significant differences in postoperative pain score and postoperative rehabilitation between the two groups(Plication of angiojet in the treatment of acute lower limb artery thromboembolism disease is safe and effective,minimally invasive,quicker recovery after operation,less postoperative complications,which is more suitable for the treatment of femoral popliteal arterial thromboembolism *** the thrombus removal is not satisfactory,the combination of coronary artery aspiration catheter and

关键词： Acute lower extremity arterial embolism Angiojet thrombectomy Postoperative complications Ankle brachial index Postoperative rehabilitation

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Theoretical and numerical simulation investigation of deep hole dispersed charge cut blasting

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International Journal of Coal Science & Technology 2023年第1期10卷 87-107页

作者： Chengxiao li Renshu Yang Yanbing Wang Yiqiang Kang Yuantong Zhang pin Xie School of Mechanics and Civil Engineering ChinaUniversity of Mining and Technology-BeijingBeijing 100083China School of Civil and Resource Engineering Universityof Science and Technology BeijingBeijing 100083China Gubei Coal Mine of Huaizhe Coal and Electricity Co. LtdHuainan 232150China

Drilling and blasting methods have been used as a common driving technique for shallow-hole driving and blasting in rock *** the advent of digital electronic detonators and the need for increased production efciency,the traditional blasting design is no longer suitable for deep hole *** this paper,a disperse charge cut blasting method was proposed to address the issues of low excavation depth and high block rate in deep hole undercut ***,a blasting model was used to illustrate the mechanism of the deep hole dispersive charge cut blasting ***,continuous charge and dispersed charge blasting models were developed using the smooth particle hydrodynamics-fnite element method(SPHFEM).The cutting parameters were determined theoretically,and the cutting efciency was introduced to evaluate the cutting *** blasting efects of the two charging models were analyzed utilizing the evolution law of rock damage,the number of rock particles thrown,and the cutting *** results show that using a dispersed charge improves the cutting efciency by about 20%and the rock breakage for the deep hole cut blasting compared to the traditional continuous *** addition,important parameters such as cutting hole spacing,cutting hole depth and upper charge proportion also have a signifcant impact on the cutting ***,the deep hole dispersed charge cut blasting technology is combined with the digital electronic detonator through the feld engineering *** provides a reference for the subsequent deep hole cutting blasting and the use of electronic detonators in rock roadways.

关键词： Deep hole blasting Cut blasting Dispersed charge SPH-FEM Digital electronic detonator

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Weighted Marginal Fisher Analysis with Spatially Smooth for aircraft recognition

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Chinese Journal of Aeronautics 2014年第1期27卷 110-116页

作者： Wei Zhenzhong liu chang li Nan Precision Opto-mechatrionics Technology Key Laboratory of Education MinistryBeihang University

Due to limitations to extract invariant features for recognition when the aircraft presents various poses and lacks enough samples for training, a novel algorithm called Weighted Marginal Fisher Analysis with Spatially Smooth （WMFA-SS） for extracting invariant features in aircraft rec- ognition is proposed. According to the Graph Embedding （GE） framework, Heat Kernel function is firstly introduced to characterize the interclass separability when choosing the weights of penalty graph. Furthermore, Laplacian penalty is applied to constraining the coefficients to be spatially smooth in this algorithm. Laplacian penalty is able to incorporate the prior information that neigh- boring pixels are correlated. Besides, using a Laplacian penalty can also avoid the singularity of Laplacian matrix of intrinsic graph. Once compact representations of the images are obtained, it can be considered as invariant features and then be performed in classification to recognize different patterns of aircraft. Real aircraft recognition experiments show the superiority of our proposed WMFA-SS in comparison to other GE algorithms and the current aircraft recognition algorithm; the accuracy rate of our proposed method is 90.00% for dataset BH-AIR1.0 and 99.25% for dataset BH-AIR2.0.

关键词： Aircraft dataset Aircraft recognition Graph Embedding Invariant feature Laplacian operator Subspace learning

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Design and simulation of a Torus topology for network on chip

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Journal of Systems Engineering and Electronics 2008年第4期19卷 694-701页

作者： Wu chang li Yubai Chai Song DSP Lab School of Communication and Information Engineering~Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Aiming at the applications of NOC （network on chip） technology in rising scale and complexity on chip systems, a Torus structure and corresponding route algorithm for NOC is proposed. This Torus structure improves traditional Torus topology and redefines the denotations of the routers. Through redefining the router denotations and changing the original router locations, the Torus structure for NOC application is reconstructed. On the basis of this structure, a dead-lock and live-lock free route algorithm is designed according to dimension increase. System C is used to implement this structure and the route algorithm is simulated. In the four different traffic patterns, average, hotspot 13%, hotspot 67% and transpose, the average delay and normalization throughput of this Torus structure are evaluated. Then, the performance of delay and throughput between this Torus and Mesh structure is compared. The results indicate that this Torus structure is more suitable for NOC applications.

关键词： network on chip Torus route System C simulation

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Data-Driven Leader-Follower Output Synchronization for Networked Non-linear Multi-Agent Systems with Switching Topology and Time-Varying Delays

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Journal of Systems Science & Complexity 2018年第1期31卷 87-102页

作者： li chang-Jiang liU Guo-ping Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 China School of Engineering University of South Wales Pontypridd CF37 1DL UK Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 China

This paper studies the output synchronization problem for a class of networked non-linear multi-agent systems with switching topology and time-varying delays. To synchronize the outputs,a leader is introduced whose connectivity to the followers varies with time, and a novel data-driven consensus protocol based on model free adaptive control is proposed, where the reference input of each follower is designed to be the time-varying average of the neighboring agents＇ outputs. Both the case when the leader is with a prescribed reference input and the case otherwise are *** proposed protocol allows for time-varying delays, switching topology, and does not use the agent structure or the dynamics information implicitly or explicitly. Sufficient conditions are derived to guarantee the closed-loop stability, and conditions for consensus convergence are obtained, where only a joint spanning tree is required. Numerical simulations and practical experiments are conducted to demonstrate the effectiveness of the proposed protocol.

关键词： Data-driven networked nonlinear multi-agent system output synchronization switching topology time-varying delay

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Free energy calculation of single molecular interaction using Jarzynski's identity method:the case of HIV-1 protease inhibitor system

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Acta Mechanica Sinica 2012年第3期28卷 891-903页

作者： De-chang li Bao-Hua Ji Biomechanics and Biomaterials Lab Department of Applied MechanicsBeijing Institute of TechnologyKey Laboratory.of Dynamics and Control of Flight VehicleMinistry of Education100081 BeijingChina

Jarzynski＇ identity （JI） method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been well tested in complex systems such as ligand-receptor molecular pairs. In this paper, we applied a huge number of steered molec- ular dynamics （SMD） simulations to dissociate the protease of human immunodeficiency type I virus （HIV-1 protease） and its inhibitors. We showed that because of intrinsic com- plexity of the ligand-receptor system, the energy barrier pre- dicted by JI method at high pulling rates is much higher than experimental results. However, with a slower pulling rate and fewer switch times of simulations, the predictions of JI method can approach to the experiments. These results sug- gested that the JI method is more appropriate for reconstruct- ing free energy landscape using the data taken from experi- ments, since the pulling rates used in experiments are often much slower than those in SMD simulations. Furthermore, we showed that a higher loading stiffness can produce higher precision of calculation of energy landscape because it yields a lower mean value and narrower bandwidth of work distri- bution in SMD simulations.

关键词： Molecular dynamics simulation. Single molecu-lar interaction ~ Molecular biomechanics ~ Steered moleculardynamics ~ Free energy calculation

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Dynamical Properties of Two Coupled Dissipative QED Cavities Driven by Coherent Fields

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Communications in Theoretical Physics 2007年第2X期48卷 232-242页

作者： HOU Bang-pin WANG Shun-Jin WANG Gang SUN Wei-li School of Physics and Electronic Engineering Sichuan Normal University Chengdu 610066 China Department of Physics Sichuan University Chengdu 610065 China College of Computer and Communication Engineering Southwest Jiaotong University Chengdu 610031 China

When two identical QED cavities driven by the coherent fields are located in a uniform environment, in addition to dissipation, there appears an indirect coupling between the two cavities induced by the background fields. We investigate the effects of the coherent fields, the dissipation as well as the incoherent coupling on the following dynamical properties of the system： photon transfer, reversible decoherence, and quantum state transfer, etc. We find that the photons in the cavities do not leak completely into the environment due to the collective coupling between the cavities and the enviroment, and the photons are transferred irreversibly from the cavity with more photons to the cavity with less ones due to the incoherent coupling so that they are equally distributed among the two cavities. The coherent field pumping on the two cavities increases the mean photons, complements the revived magnitude of the reversible decoherence, but hinders the quantum state transfer between the two cavities. The above phenomena may find applications in quantum communication and other basic fields.

关键词： photon transfer reversible decoherence quantum state transfer algebraic dynamical method two coupled dissipative QED cavities driven by coherent fields

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