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Investigation on the Deformation and Failure Patterns of Loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an,China

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Journal of Earth Science 2024年第1期35卷 235-247页

作者： Lina ma Shengwen qi Songfeng Guo qiangbing Huang Xiaokun Hou Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Department of Geological Engineering Chang'an UniversityXi'an 710054China

The large-scale implementation of the Gully Stabilization and Land Reclamation(GSLR)project induces various failures of loess slopes due to excavation in Yan'an,***,the deformation and failure behavior of these excavated loess slopes have not been fully *** this study,field investigation was undertaken for analyzing the distributions and failure features of excavation-induced loess slope *** is found that plastic failure mainly occurs in Q_(3) loess layers and brittle failure in Q_(2).To understand the underlying failure mechanism,a series of triaxial shear tests were conducted on intact Q_(3) and Q_(2) loess samples that with different water contents,namely natural water content(natural),dry side of the natural value(drying 5%),and wet side(wetting 5%).The characteristics of stress-strain curves and failure modes of the samples were *** show that the stress-strain curves of Q_(2) samples are dominated by strain-softening characteristics,while Q_(3) samples mainly exhibit strain-harden features except in the drying ***,shear failures of Q_(3) specimens are mainly caused by shear crack planes(single,X or V-shaped).For Q_(2) loess,the dominance of tensile cracks is observed on the surface of damaged *** disclose the different failure modes of excavated slopes located in different strata,that is,the arc sliding failure of Q_(3) loess slopes and the stepped tensile failure of Q_(2) loess slopes,and are helpful in the design and management of the ongoing GSLR projects in the Loess Plateau.

关键词： loess slope slope stability failure patterns deformation

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Perioperative outcomes of transvaginal specimen extraction laparoscopic total gastrectomy and conventional laparoscopicassisted total gastrectomy

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1527-1536页

作者： Zhi-Cao Zhang wen-Sheng Wang Jiang-Hong Chen Yuan-Hang ma qi-Fa Luo Yun-Bo Li Yang Yang Dan ma Department of General Surgery Xinqiao Hospital of Army Medical UniversityChongqing 400037China

BACKGROUND Natural orifice specimen extraction surgery(NOSES)has emerged as a promising alternative compared to conventional laparoscopic-assisted total gastrectomy(LATG)for treating gastric cancer(GC).However,evidence regarding the efficacy and safety of NOSES for GC surgery is *** study aimed to compare the safety and feasibility,in addition to postoperative complications of NOSES and *** Dual circular staplers were used in Roux-en-Y digestive tract reconstruction for transvaginal specimen extraction LATG,and its outcomes were compared with LATG in a cohort of 51 GC patients with tumor size≤5 *** study was conducted from may 2018 to September 2020,and patients were categorized into the NOSES group(n=22)and LATG group(n=29).Perioperative parameters were compared and analyzed,including patient and tumor characteristics,postoperative outcomes,and anastomosis-related complications,postoperative hospital stay,the length of abdominal incision,difference in tumor type,postoperative complications,and postoperative *** Postoperative exhaust time,operation duration,mean postoperative hospital stay,length of abdominal incision,number of specific staplers used,and Brief Illness Perception Questionnaire score were significant in both groups(Pmally invasive incision that met aesthetic *** were no significant differences in gender,age,tumor type,postoperative complications,and postoperative survival between the two *** The application of dual circular staplers in Roux-en-Y digestive tract reconstruction combined with NOSES gastrectomy is safe and *** approach offers better short-term outcomes compared to LATG,while long-term survival

关键词： Gastric cancer Circular stapler Natural orifice specimen extraction surgery Laparoscopic-assisted total gastrectomy

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Transforming Adolescent Smiles:Correcting Skeletal mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners

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Current Medical Science 2024年第3期44卷 657-666页

作者： wen-jie FAN Jia-qi ZHANG Jia-qi ZHAN Li HU Li-li CHEN Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Stomatology Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Wuhan National High magnetic Field Center Wuhan430074China The Affiliated Lianyungang Hospital of Xuzhou Medical University/The First People’s Hospital of Lianyungang Lianyungang222000China The First Affiliated Hospital of Kangda College of Nanjing Medical University/The First People’s Hospital of Lianyungang Lianyungang222000China

maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental *** traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial *** recent years,an invisible orthodontic technique,without brackets,has become increasingly ***,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect *** case report presents an adolescent patient with bimaxillary protrusion and mandibular *** on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular *** patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the *** case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction ***,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists.

关键词： mandibular retrusion esthetic orthodontic treatment clear aligners growth potential

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Exploring deep learning for landslide mapping:A comprehensive review

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China Geology 2024年第2期7卷 330-350页

作者： Zhi-qiang Yang wen-wen qi Chong Xu Xiao-yi Shao College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China National Institute of Natural Hazards Ministry of Emergency ManagementBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China

A detailed and accurate inventory map of landslides is crucial for quantitative hazard assessment and land *** methods relying on change detection and object-oriented approaches have been criticized for their dependence on expert knowledge and subjective *** advancements in highresolution satellite imagery,coupled with the rapid development of artificial intelligence,particularly datadriven deep learning algorithms(DL)such as convolutional neural networks(CNN),have provided rich feature indicators for landslide mapping,overcoming previous *** this review paper,77representative DL-based landslide detection methods applied in various environments over the past seven years were *** study analyzed the structures of different DL networks,discussed five main application scenarios,and assessed both the advancements and limitations of DL in geological hazard *** results indicated that the increasing number of articles per year reflects growing interest in landslide mapping by artificial intelligence,with U-Net-based structures gaining prominence due to their flexibility in feature extraction and ***,we explored the hindrances of DL in landslide hazard research based on the above research *** such as black-box operations and sample dependence persist,warranting further theoretical research and future application of DL in landslide detection.

关键词： Landslide mapping Quantitative hazard assessment Deep learning Artificial intelligence Neural network Big data Geological hazard survery engineering

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L-Type Calcium Channel Modulates Low-Intensity Pulsed Ultrasound-Induced Excitation in Cultured Hippocampal Neurons

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Neuroscience Bulletin 2024年第7期40卷 921-936页

作者： wen-Yong Fan Yi-Ming Chen Yi-Fan Wang Yu-qi Wang Jia-qi Hu wen-Xu Tang Yi Feng qian Cheng Lei Xue State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghai 200433China Department of Physiology and Neurobiology School of Life SciencesFudan UniversityShanghai 200438China Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education Tongji UniversityShanghai 200070China Center for Rehabilitation Medicine Department of Pain ManagementZhejiang Provincial People's HospitalAffliated People's HospitalHangzhou Medical CollegeHangzhou 310014China Department of Critical Care Medicine Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Research Institute of Intelligent Complex Systems Fudan UniversityShanghai 200433China

As a noninvasive technique,ultrasound stimulation is known to modulate neuronal activity both in vitro and in *** latest explanation of this phenomenon is that the acoustic wave can activate the ion channels and further impact the electrophysiological properties of targeted ***,the underlying mechanism of low-intensity pulsed ultrasound(LIPUS)-induced neuro-modulation effects is still ***,we characterize the excitatory effects of LIPUS on spontaneous activity and the intracellular Ca^(2+)homeostasis in cultured hippocampal *** whole-cell patch clamp recording,we found that 15 min of 1-MHz LIPUS boosts the frequency of both spontaneous action potentials and spontaneous excitatory synaptic currents(sEPSCs)and also increases the amplitude of sEPSCs in hippocampal *** phenomenon lasts for>10 min after LIPUS *** with Ca^(2+)imaging,we clarified that LIPUS increases the[Ca^(2+)]cyto level by facilitating L-type Ca^(2+)channels(LTCCs).In addition,due to the[Ca^(2+)]cyto elevation by LIPUS exposure,the Ca^(2+)-dependent CaMKII-CREB pathway can be activated within 30 min to further regulate the gene transcription and protein *** work suggests that LIPUS regulates neuronal activity in a Ca^(2+)-dependent manner via *** may also explain the multi-activation effects of LIPUS beyond *** stimulation potentiates spontaneous neuronal activity by increasing Ca^(2+)influx.

关键词： Low-intensity pulsed ultrasound Neuromodulation L-type calcium channel Hippocampal neuron

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Response mechanism of soil microorganisms to simulated precipitation in the source wetland of qinghai Lake

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Ecological Processes 2024年第2期13卷 61-71页

作者： Xinye Wang Ni Zhang Kelong Chen Tiexi Chen Desheng qi Yuanxi ma School of Geographical Sciences Qinghai Normal University National Positioning Observation and Research Station of qinghai Lake Wetland Ecosystem in qinghai National Forestry and Grassland Administration Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal University School of Geographical Sciences Nanjing University of Information Science and Technology qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

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Enhancement of comprehensive properties of Nb–Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： Wei Wei qi Wang Rui-Run Chen Chao-wen Zheng Yan-qing Su National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of Technology

This study examines the microstructure,mechanical properties （with a focus on room-temperature toughness）, and oxidation resistance of Ho-doped NbDSi based in-situ composites. The base alloy consists of the coarse primary Nb5Si3phase and the Nb5Si3+Nbss （Nb solid solution） eutectic cells. Ho doping influences the solidification path. When the Ho doping is higher than0.2 at%, the alloys transform into eutectic alloys. Ho can be solid-solved in trace amounts in the Nbss phase. However, most of Ho forms a stable Ho oxide phase, which alleviates oxygen contamination problem to some ***, the interface separation between Ho oxide and other phases reduces the plastic deformation ***, with 0.4 at%Ho doping, the KQvalue is18.03 MPa·m1/2, which is 31.1%higher than that of the base alloy. The strength of the Ho-doped alloys does not deteriorate with an increase in toughness. However, the large network-like Ho2O3in the 0.8Ho alloy causes a decrease in toughness and strength. In addition, the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping, the oxidation mass gain per unit area is 10.16 mg·cm2, which is 39.7%lower than that of the base alloy.

关键词： Ho Microstructure Nb–Si based composites Properties Rare earth elements

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Influence of tectonic preservation conditions on the nanopore structure of shale reservoir: A case study of Wufeng-Longmaxi Formation shale in western Hubei area, south China

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Petroleum Science 2024年第4期21卷 2203-2217页

作者： Meng Xiang Shang Xu Ya-Ru wen qi-Yang Gou Bing-Chang Liu National Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Hubei Key Laboratory of Resources and Eco-environment Geology Hubei Geological Survey Key Laboratory of Tectonics and Petroleum Resources Ministry of Education China University of Geosciences

Tectonism is one of the dominant factors affecting the shale pore structure. However, the control of shale pore structure by tectonic movements is still controversial, which limits the research progress of shale gas accumulation mechanism in the complex tectonic region of southern China. In this study, 34 samples were collected from two exploratory wells located in different tectonic locations. Diverse experiments,e.g., organic geochemistry, XRD analysis, FE-SEM, low-pressure gas adsorption, and high-pressure mercury intrusion, were conducted to fully characterize the shale reservoir. The TOC, Ro, and mineral composition of the shale samples between the two wells are similar, which reflects that the shale samples of the two wells have proximate pores-generating capacity and pores-supporting ***, the pore characteristics of shale samples from two wells are significantly different. Compared with the stabilized zone shale, the porosity, pore volume, and specific surface area of the deformed zone shale were reduced by 60.61%, 64.85%, and 27.81%, respectively. Moreover, the macroscopic and fine pores were reduced by 54.01% and 84.95%, respectively. Fault activity and uplift denudation are not conducive to pore preservation, and the rigid basement of Huangling uplift can promote pore preservation. These three factors are important reasons for controlling the difference in pore structure between two wells shales. We established a conceptual model of shale pores evolution under different tectonic preservation conditions. This study is significant to clarify the scale of shale gas formation and enrichment in complex tectonic regions, and helps in the selection of shale sweet spots.

关键词： Shale gas Pore structure Tectonic preservation conditions Shale gas enrichment mechanism

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Realizing the excellent oxidation resistance of an environmental barrier coating through aluminum surface modification

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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： Lin Dong wen-qi Yang Lin Chen Guan-Jun Yang Chang-Jiu Li State Key Laboratory for Mechanical Behavior of materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in China Aerospace Science and Technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

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Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array

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China Communications 2024年第4期21卷 23-37页

作者： ma Yue ma Ruiqian Lin Zhi Yang Weiwei Cai Yueming Miao Chen Wu wen Key Laboratory of Near-Range RF Sensing ICs&Microsystems(NJUST) Ministry of EducationSchool of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China College of Electronic Engineering National University of Defense TechnologyHefei 230037China College of Communications Engineering Army Engineering University of PLANanjing 210007China

In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently *** this basis,the covertness constraint and CAoI are derived in closed *** facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and *** results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length ***,we observe that smaller beam pointing error at Bob leads to improvements in CAoI.

关键词： age of information covert communication retrodirective array time modulation

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