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A fast forward computational method for nuclear measurement using volumetric detection constraints

Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： qiong Zhang Lin-Lv Lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation models.Among the various detection tools that use nuclear sources,the detector response can reflect various types of information of the medium.The Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex environments.However,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response results.Therefore,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is proposed.First,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo simulation.Then,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion model.The environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection volume.Finally,the method is applied to a neutron porosity tool for verification.In various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 p.u.In field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

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On Hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： Fang DUAN qiong-xiang HUANG School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set S.In this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=Zm×H is a semiproduct of Zmby a subgroup H of G.In particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=Zm×H.In addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(Zm,{a})×_φ C(H,S) is also a Cayley digraph if φ is a homomorphism from H to{1,-1} ≤ Zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

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Enhanced and asymmetric signatures of hybridization at climatic margins: Evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-Feng Huang Clive T.Darwell Yan-qiong Peng CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China National Center for Genetic Engineering and Biotechnology(BIOTEC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern Thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene flow.Signatures of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales.

关键词： Hybridization Heterospecific visitation Fig Pollinator wasp Asymmetric gene flow

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Effect of health education based on information-motivationbehavioral skills model on patients with unilateral vestibular dysfunction

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World Journal of Clinical Cases 2024年第5期12卷 903-912页

作者： qiong Shi Ruo-Jun Wu Jiang Liu Department of Neurology Wuahan Fourth HospitalWuhan 430000Hubei ProvinceChina Department of Critical Care Medicine Wuhan No.1 HospitalWuhan 430033Hubei ProvinceChina

BACKGROUND Vestibular dysfunction(VH)is a common concomitant symptom of late peri-pheral vestibular lesions,which can be trauma,poisoning,infection,heredity,and neurodegeneration,but about 50%of the causes are unknown.The study uses the information-motivation-behavioral skills(IMB)model for health education,effectively improve the quality of life,increase their self-confidence,reduce anxiety and depression,and effectively improve the psychological state of patients.AIM To explore the effect of health education based on the IMB model on the degree of vertigo,disability,anxiety and depression in patients with unilateral vestibular hypofunction.METHODS The clinical data of 80 patients with unilateral vestibular hypofunction from January 2019 to December 2021 were selected as the retrospective research objects,and they were divided into the control group and the observation group with 40 cases in each group according to different nursing methods.Among them,the control group was given routine nursing health education and guidance,and the observation group was given health education and guidance based on the IMB model.The changes in self-efficacy,anxiety and depression,and quality of life of patients with unilateral VH were compared between the two groups.RESULTS There was no significant difference in General Self-Efficacy Scale(GSES)scale scores between the two groups of patients before nursing(P>0.05),which was comparable;after nursing,the GSES scale scores of the two groups were higher than those before nursing.The nursing group was higher than the control group,and the difference was statistically significant(P0.05).After nursing,the HADS score,anxiety,and depression subscale scores of the two groups of patients were lower than those before nursing,and the nursing group was lower than the control group,and the difference was statistically

关键词： Information-motivation-behavioral skills model Health education Vestibular function Quality of life Selfefficacy

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An Intelligent Sensor Data Preprocessing Method for OCT Fundus Image Watermarking Using an RCNN

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1549-1561页

作者： Jialun Lin qiong Chen College of Biomedical Information and Engineering Hainan Medical UniversityHaikou571199China TJ-YZ School of Network Science Haikou University of EconomicsHaikou571127China Department of Earth System Science Ministry of Education Key Laboratory for Earth SystemModelingInstitute forGlobal Change StudiesTsinghua UniversityBeijing100084China

Watermarks can provide reliable and secure copyright protection for optical coherence tomography(OCT)fundus images.The effective image segmentation is helpful for promoting OCT image watermarking.However,OCT images have a large amount of low-quality data,which seriously affects the performance of segmentationmethods.Therefore,this paper proposes an effective segmentation method for OCT fundus image watermarking using a rough convolutional neural network(RCNN).First,the rough-set-based feature discretization module is designed to preprocess the input data.Second,a dual attention mechanism for feature channels and spatial regions in the CNN is added to enable the model to adaptively select important information for fusion.Finally,the refinement module for enhancing the extraction power of multi-scale information is added to improve the edge accuracy in segmentation.RCNN is compared with CE-Net and MultiResUNet on 83 gold standard 3D retinal OCT data samples.The average dice similarly coefficient(DSC)obtained by RCNN is 6%higher than that of CE-Net.The average 95 percent Hausdorff distance(95HD)and average symmetric surface distance(ASD)obtained by RCNN are 32.4%and 33.3%lower than those of MultiResUNet,respectively.We also evaluate the effect of feature discretization,as well as analyze the initial learning rate of RCNN and conduct ablation experiments with the four different models.The experimental results indicate that our method can improve the segmentation accuracy of OCT fundus images,providing strong support for its application in medical image watermarking.

关键词： Watermarks image segmentation rough convolutional neural network attentionmechanism feature discretization

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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge

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Structural Durability & Health Monitoring 2024年第3期18卷 361-376页

作者： Xilong Zheng qiong Wang Di Guan School of Civil and Architectural Engineering Harbin UniversityHarbin150076China

The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively.

关键词： Continuous rigid frame bridge rehabilitation long-term monitoring field load test safety standard determination

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Defective MnO2 functional separator coating as effective polysulfide mediators for lithium–sulfur batteries

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Tungsten 2024年第3期6卷 536-543页

作者： Yan-Qi Feng qiong-qiong Lu Hui Liu School of Materials & Environment Engineering Chengdu Technological University School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials Shaanxi University of Science and Technology Institute of Materials Henan Key Laboratory of Advanced Conductor Materials Henan Academy of Sciences Institute of Materials Chemistry Leibniz Institute for Solid State and Materials Research (IFW) Dresden e.V.

Advanced energy storage systems are in urgent need nowadays due to the rising demand in mobile devices and electric vehicles [1]. Lithium–sulfur（Li–S） batteries are intensively studied due to the high theoretical specific capacity(1675 m Ah·g-1) and energy density(2600 Wh·kg-1), as well as natural abundant and environmentally friendly of sulfur.

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Life forms affect beta-diversity patterns of larch forests in China

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Plant Diversity 2024年第1期46卷 49-58页

作者： Wenjing Fang qiong Cai Chengjun Ji Jiangling Zhu Zhiyao Tang Jingyun Fang School of Ecology and Environmental Science Yunnan UniversityKunming 650091China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Beta-diversity reflects the spatial changes in community species composition which helps to understand how communities are assembled and biodiversity is formed and maintained. Larch(Larix) forests, which are coniferous forests widely distributed in the mountainous and plateau areas in North and Southwest China, are critical for maintaining the environmental conditions and species diversity. Few studies of larch forests have examined the beta-diversity and its constituent components(species turnover and nestedness-resultant components). Here, we used 483 larch forest plots to determine the total betadiversity and its components in different life forms(i.e., tree, shrub, and herb) of larch forests in China and to evaluate the main drivers that underlie this beta-diversity. We found that total betadiversity of larch forests was mainly dependent on the species turnover component. In all life forms,total beta-diversity and the species turnover component increased with increasing geographic, elevational, current climatic, and paleoclimatic distances. In contrast, the nestedness-resultant component decreased across these same distances. Geographic and environmental factors explained 20%-25% of total beta-diversity, 18%-27% of species turnover component, and 4%-16% of nestedness-resultant component. Larch forest types significantly affected total beta-diversity and species turnover component. Taken together, our results indicate that life forms affect beta-diversity patterns of larch forests in China, and that beta-diversity is driven by both niche differentiation and dispersal limitation. Our findings help to greatly understand the mechanisms of community assemblies of larch forests in China.

关键词： Beta-diversity Species turnover Nestedness-resultant Geographic distance Climatic distance Larch forest

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Cationic Conjugated Oligomers for Efficient and Rapid Antibacterial Photodynamic Therapy via Both Type Ⅰ and Type Ⅱ Pathways

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Chinese Journal of Chemistry 2024年第1期42卷 61-66页

作者： Huan Wang Shuwen Guo qiong Yuan Meiqi Li Yanli Tang Country Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'anShaanxi 710119China

Recently,photodynamic therapy(PDT)has attracted wide attention due to its less susceptibility to drug resistance,broad-spectrum biocidal activity and biosafety in normal tissues.However,the traditional photosensitizers(Ps)face the disadvantage of poor therapeutic efficacy due to the requirement of an aerobic environment to generate ^(1)O_(2) through Type Ⅱ pathway.Herein,we designed and synthesized a novel cationic conjugated oligomer oligo(phenylene vinylene)(OPV)and studied its antibacterial photodynamic activity against both Gram-negative Escherichia coli(E.coli)and Gram-positive bacteria methicillin-resistant Staphylococcus aureus(MRSA).Importantly,the OpV can rapidly produce reactive oxygen species(ROs)through double pathways,Type Ⅰ and Ⅱ mechanism under white light irradiation,and efficiently kill E.coli and MRSA at a nanomolar level.The dual type photosensitizing capability makes OPV promising for enhanced PDT to treat pathogens and tumors in complex environments.

关键词： Conjugated oligomers Antibacterial photodynamic therapy Oligo(phenylene vinylene) Reactive oxygen species Typelandll pathways

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Robotic vs laparoscopic abdominoperineal resection for rectal cancer:A propensity score matching cohort study and metaanalysis

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1280-1290页

作者： Li Song Wen-qiong Xu Zheng-Qiang Wei Gang Tang Department of Gastrointestinal Surgery Chengdu Fifth People's HospitalChengdu 610000Sichuan ProvinceChina Department of Nephrology Chengdu Fifth People's HospitalChengdu 610000Sichuan ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400000China Division of Biliary Tract Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Robotic surgery(RS)is gaining popularity;however,evidence for abdominoperineal resection(APR)of rectal cancer(RC)is scarce.AIM To compare the efficacy of RS and laparoscopic surgery(LS)in APR for RC.METHODS We retrospectively identified patients with RC who underwent APR by RS or LS from April 2016 to June 2022.Data regarding short-term surgical outcomes were compared between the two groups.To reduce the effect of potential confounding factors,propensity score matching was used,with a 1:1 ratio between the RS and LS groups.A meta-analysis of seven trials was performed to compare the efficacy of robotic and laparoscopic APR for RC surgery.RESULTS Of 133 patients,after propensity score matching,there were 42 patients in each group.The postoperative complication rate was significantly lower in the RS group(17/42,40.5%)than in the LS group(27/42,64.3%)(P=0.029).There wasno significant difference in operative time(P=0.564),intraoperative transfusion(P=0.314),reoperation rate(P=0.314),lymph nodes harvested(P=0.309),or circumferential resection margin(CRM)positive rate(P=0.314)between the two groups.The meta-analysis showed patients in the RS group had fewer positive CRMs(P=0.04),lesser estimated blood loss(P<0.00001),shorter postoperative hospital stays(P=0.02),and fewer postoperative complications(P=0.002)than patients in the LS group.CONCLUSION Our study shows that RS is a safe and effective approach for APR in RC and offers better short-term outcomes than LS.

关键词： Robotic surgery Laparoscopic surgery Abdominoperineal resection Postoperative complications Propensity score

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