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Plant phenols contents and their changes with nitrogen availability in peatlands of northeastern China

Journal of Plant Ecology 2020年第6期13卷 713-721页

作者： Di Wu Xian-Wei Wang shi-qi xu Chong-Juan Chen Rong Mao xue-Yan Liu School of Earth System Science Tianjin UniversityTianjin 300072China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102JilinChina College of Forestry Jiangxi Agricultural UniversityNanchang 330045JiangxiChina

Aims Climate warming and increasing nitrogen(N)deposition have influenced plant nutrient status and thus plant carbon(C)fixation and vegetation composition in boreal ***,which are secondary metabolites in plants for defense and adaptation,also play important roles in regulating peatland C dynamics due to their anti-decomposition ***,how the phenolic levels of different functional types of plants vary depending on nutrient availability remain unclear in boreal *** Here,we investigated total phenols contents(TPC)and total tannins contents in leaves of 11 plant species in 18 peatlands of the Great Hing’an Mountains area in northeastern China,and examined their variations with leaf N and phosphorus(P)and underlying *** Findings Shrubs had higher TPC than graminoids,indicating less C allocation to defense and less uptake of organic N in faster-growing and nonmycorrhizal graminoids than in slower-growing and mycorrhizal *** shrubs,leaf TPC decreased with increasing N contents but was not influenced by changing leaf phosphorus(P)contents,which suggested that shrubs would reduce the C investment for defense with increasing N ***,leaf TPC of graminoids increased with leaf N contents and decreased with leaf P *** graminoids are more N-limited and less P-limited,we inferred that graminoids would increase the defensive C investment under increased nutrient *** concluded that shrubs would invest more C in growth than in defense with increasing N availability,but it was just opposite for graminoids,which might be an important mechanism to explain the resource competition and encroachment of shrubs in boreal peatlands in the context of climate warming and ever-increasing N deposition.

关键词： boreal peatlands plant phenols plant defense theory plant functional types nitrogen availability

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Alloy strategy to synthesize Pt-early transition metal oxide interfacial catalysts

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Nano Research 2024年第4期17卷 3390-3397页

作者： shi-Long xu Hang Nan Wanqun Zhang Yue Lin Sheng-qi Chu Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant ***,the enhancement of performance is often limited by the insufficient metal/metal oxide *** this work,we demonstrate a general synthesis of Pt-early transition metal oxide(Pt-MO_(x),M=Ti,Zr,V,and Y)catalysts with rich interfacial sites,which is based on the air-induced surface segregation and oxidation of M in the supported Pt-M alloy *** characterizations verify the dynamic structural response of Pt-M alloy catalysts to air and the formation of Pt-MO_(x) catalysts with abundant interfacial *** prepared Pt-TiO_(x) interfacial catalysts exhibit improved performance in hydrogenation reactions of benzaldehyde,nitrobenzene,styrene,and furfural,as a result of the heterolytic dissociation of H_(2) at Pt-metal oxide interfacial sites.

关键词： Pt-early transition metal oxide interfacial catalyst alloy oxidation strategy interfacial sites hydrogenation reactions heterolytic dissociation

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Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2024年第10期30卷 1393-1404页

作者： Ming-Hui Zeng qi-Yu shi Liang xu Yu-qiang Mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Gastroenterology Cangzhou People’s HospitalCangzhou 061000Hebei ProvinceChina Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Tianjin Research Institute of Liver Diseases Tianjin 300192China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic *** date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of *** patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very *** To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle *** The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently *** and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 *** efficacy of the EDAS was evaluated in the initial ***,the efficacy of the EDAS was internally verified in a validation *** The EDAS consisted of 33 items in six dimensions,with a total of 165 *** EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise *** The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population.

关键词： Fatty liver Lifestyle intervention Behavioral change Patient adherence Compliance

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Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： Ye TIAN Tielin shi qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

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Dynamic interwell connectivity analysis of multi-layer waterflooding reservoirs based on an improved graph neural network

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Petroleum Science 2024年第2期21卷 1062-1080页

作者： Zhao-qin Huang Zhao-xu Wang Hui-Fang Hu shi-Ming Zhang Yong-Xing Liang qi Guo Jun Yao School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Exploration and Development Research Institute Shengli OilfieldSINOPECDongying257015ShandongChina

The analysis of interwell connectivity plays an important role in the formulation of oilfield development plans and the description of residual oil distribution. In fact, sandstone reservoirs in China's onshore oilfields generally have the characteristics of thin and many layers, so multi-layer joint production is usually adopted. It remains a challenge to ensure the accuracy of splitting and dynamic connectivity in each layer of the injection-production wells with limited field data. The three-dimensional well pattern of multi-layer reservoir and the relationship between injection-production wells can be equivalent to a directional heterogeneous graph. In this paper, an improved graph neural network is proposed to construct an interacting process mimics the real interwell flow regularity. In detail, this method is used to split injection and production rates by combining permeability, porosity and effective thickness, and to invert the dynamic connectivity in each layer of the injection-production wells by attention *** on the material balance and physical information, the overall connectivity from the injection wells,through the water injection layers to the production layers and the output of final production wells is established. Meanwhile, the change of well pattern caused by perforation, plugging and switching of wells at different times is achieved by updated graph structure in spatial and temporal ways. The effectiveness of the method is verified by a combination of reservoir numerical simulation examples and field example. The method corresponds to the actual situation of the reservoir, has wide adaptability and low cost, has good practical value, and provides a reference for adjusting the injection-production relationship of the reservoir and the development of the remaining oil.

关键词： Graph neural network Dynamic interwell connectivity Production-injection splitting Attention mechanism Multi-layer reservoir

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On Isodual Double Toeplitz Codes

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Journal of Systems Science & Complexity 2024年第5期37卷 2196-2206页

作者： shi Minjia xu Li SOLé Patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education School of Mathematical Sciences Anhui University State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences CNRS University of Aix Marseille Centrale Marseille

Double Toeplitz（shortly DT） codes are introduced here as a generalization of double circulant codes. The authors show that such a code is isodual, hence formally self-dual（FSD）. FSD codes form a far-reaching generalization of self-dual codes, the most important class of codes of rate one-half. Self-dual DT codes are characterized as double circulant or double negacirculant. Likewise, even binary DT codes are characterized as double circulant. Numerical examples obtained by exhaustive search show that the codes constructed have best-known minimum distance, up to one unit, amongst formally self-dual codes, and sometimes improve on the known values. For q = 2, the authors find four improvements on the best-known values of the minimum distance of FSD codes. Over F4an explicit construction of DT codes, based on quadratic residues in a prime field, performs equally well. The authors show that DT codes are asymptotically good over Fq. Specifically, the authors construct DT codes arbitrarily close to the asymptotic Varshamov-Gilbert bound for codes of rate one half.

关键词： Double circulant codes double Toeplitz codes formally self-dual codes isodual codes

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An M-VCUT level set-based data-driven model of microstructures and optimization of two-scale structures

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Frontiers of Mechanical Engineering 2024年第4期19卷 73-86页

作者： Minjie SHAO Tielin shi qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The optimization of two-scale structures can adapt to the different needs of materials in various regions by reasonably arranging different microstructures at the macro scale,thereby considerably improving structural ***,a multiple variable cutting(M-VCUT)level set-based data-driven model of microstructures is presented,and a method based on this model is proposed for the optimal design of two-scale *** geometry of the microstructure is described using the M-VCUT level set method,and the effective mechanical properties of microstructures are computed by the homogenization ***,a database of microstructures containing their geometric and mechanical parameters is *** two sets of parameters are adopted as input and output datasets,and a mapping relationship between the two datasets is established to build the data-driven model of *** the optimization of two-scale structures,the data-driven model is used for macroscale finite element and sensitivity *** efficiency of the analysis and optimization of two-scale structures is improved because the computational costs of invoking such a data-driven model are much smaller than those of homogenization.

关键词： two-scale structure structural optimization M-VCUT level set homogenization radial basis function data-driven

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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： shi-Liang xu Ying-Nan Zhao Yao Yu qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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Giant bile duct dilatation in newborn:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1150-1156页

作者： Dong-Wen Quan Peng-Gang Li Xiang-Hua xu shi-qi Liu The Second Clinical Medical School Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina The First School of Clinical Medicine Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Neonatal Surgery Xi’an Children’s Hospital Affiliated Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina

BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical *** born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ *** treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control *** SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant *** patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 *** abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of *** finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary *** specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 *** on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant *** surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemos

关键词： Acute cholangitis Congenital biliary dilation Laparoscopic surgery vs Open hepatic duct-jejunostomy Case report

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ANALYSIS OF THE IMPLICIT-EXPLICIT ULTRA-WEAK DISCONTINUOUS GALERKIN METHOD FOR CONVECTION-DIFFUSION PROBLEMS

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Journal of Computational Mathematics 2024年第1期42卷 1-23页

作者： Haijin Wang Anping xu qi Tao School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Beijing Computational Science Research Center Beijing 100193China

In this paper,we first present the optimal error estimates of the semi-discrete ultra-weak discontinuous Galerkin method for solving one-dimensional linear convection-diffusion ***,coupling with a kind of Runge-Kutta type implicit-explicit time discretization which treats the convection term explicitly and the diffusion term implicitly,we analyze the stability and error estimates of the corresponding fully discrete *** fully discrete schemes are proved to be stable if the time-stepτ≤τ0,whereτ0 is a constant independent of the mesh-size ***,by the aid of a special projection and a careful estimate for the convection term,the optimal error estimate is also obtained for the third order fully discrete *** experiments are displayed to verify the theoretical results.

关键词： The ultra-weak discontinuous Galerkin method Convection-diffusion Implicitexplicit time discretization Stability Error estimate

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