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Navigation Finsler metrics on a gradient Ricci soliton

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 266-275页

作者： LI Ying MO xiao-huan WANG xiao-yang Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral inequality.Then we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein type.As its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.

关键词： gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton

Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai huan Li xiao Tang Ruonan Zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum efficiency.To tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded cell.To fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent cells.To tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV position.Then,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation schemes.We further propose an iterative power allocation algorithm based on the sequential convex approximation theory.The simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

Multilevel Attention Unet Segmentation Algorithmfor Lung Cancer Based on CT Images

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Computers, Materials & Continua 2024年第2期78卷 1569-1589页

作者： huan Wang Shi Qiu Benyue Zhang Lixuan xiao Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’anChina School of Biomedical Engineering Fourth Military Medical UniversityXi’anChina University of Illinois at Urbana Champion ChampaignUSA

Lung cancer is a malady of the lungs that gravely jeopardizes human health.Therefore,early detection and treatment are paramount for the preservation of human life.Lung computed tomography(CT)image sequences can explicitly delineate the pathological condition of the lungs.To meet the imperative for accurate diagnosis by physicians,expeditious segmentation of the region harboring lung cancer is of utmost significance.We utilize computer-aided methods to emulate the diagnostic process in which physicians concentrate on lung cancer in a sequential manner,erect an interpretable model,and attain segmentation of lung cancer.The specific advancements can be encapsulated as follows:1)Concentration on the lung parenchyma region:Based on 16-bit CT image capturing and the luminance characteristics of lung cancer,we proffer an intercept histogram algorithm.2)Focus on the specific locus of lung malignancy:Utilizing the spatial interrelation of lung cancer,we propose a memory-based Unet architecture and incorporate skip connections.3)Data Imbalance:In accordance with the prevalent situation of an overabundance of negative samples and a paucity of positive samples,we scrutinize the existing loss function and suggest a mixed loss function.Experimental results with pre-existing publicly available datasets and assembled datasets demonstrate that the segmentation efficacy,measured as Area Overlap Measure(AOM)is superior to 0.81,which markedly ameliorates in comparison with conventional algorithms,thereby facilitating physicians in diagnosis.

关键词： Lung cancer computed tomography computer-aided diagnosis Unet segmentation

Risk factors for cognitive impairment in patients with chronic kidney disease

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World Journal of Psychiatry 2024年第2期14卷 308-314页

作者： xiao-Hui Wang Yong He huan Zhou Ting xiao Ran Du Xin Zhang Department of Nephrology The Fifth Hospital of WuhanWuhan 430050Hubei ProvinceChina Department of Nephrology The Central Hospital of Enshi Tujia and Miao Autonomous PrefectureEnshi 445000Hubei ProvinceChina

BACKGROUND Chronic kidney disease(CKD)patients have been found to be at risk of concurrent cognitive dysfunction in previous studies,which has now become an important public health issue of widespread concern.AIM To investigate the risk factors for concurrent cognitive dysfunction in patients with CKD.METHODS This is a prospective cohort study conducted among patients with CKD between October 2021 and March 2023.A questionnaire was formulated by literature review and expert consultation and included questions about age,sex,education level,per capita monthly household income,marital status,living condition,payment method,and hypertension.RESULTS Logistic regression analysis showed that patients aged 60-79 years[odds ratio(OR)=1.561,P=0.015]and≥80 years(OR=1.760,P=0.013),participants with middle to high school education(OR=0.820,P=0.027),divorced or widowed individuals(OR=1.37,P=0.032),self-funded patients(OR=2.368,P=0.008),and patients with hypertension(OR=2.011,P=0.041)had a higher risk of cognitive impairment.The risk of cognitive impairment was lower for those with a college degree(OR=0.435,P=0.034)and married individuals.CONCLUSION The risk factors affecting cognitive dysfunction are age,60-79 years and≥80 years;education,primary school education or less;marital status,divorced or widowed;payment method,selffunded;hypertension;and CKD.

关键词： Cognitive impairment Cognitive dysfunction Chronic kidney disease

Y–Z deformable magnetic ring for the treatment of rectal stricture: A case report and review of literature

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World Journal of Gastroenterology 2024年第6期30卷 599-606页

作者： Miao-Miao Zhang huan-Chen Sha Yuan-Fa Qin Yi Lyu xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Treatment of postoperative anastomotic stenosis for colorectal cancer is often challenging,especially for patients who do not respond well to endoscopy.In cases where patients have undergone an enterostomy,the stenosis can be easily resolved through magnetic compression.However,common magnetic compre-ssion techniques cannot be performed on those without enterostomy.We design-ed a novel Y–Z deformable magnetic ring(Y–Z DMR)and successfully applied it to a patient with a stenosis rectal anastomosis and without enterostomy after rectal cancer surgery.CASE SUMMARY We here report the case of a 57-year-old woman who had undergone a laparo-scopic radical rectum resection(Dixon)for rectal cancer.However,she started facing difficulty in defecation 6 months after surgery.Her colonoscopy indicated stenosis of the rectal anastomosis.Endoscopic balloon dilation was performed six times on her.However,the stenosis still showed a trend of gradual aggravation.Because the patient did not undergo an enterostomy,the conventional endoscopic magnetic compression technique could not be performed.Hence,we imple-mented a Y–Z DMR implemented through the anus under single channel.The magnetic ring fell off nine days after the operation and the rectal stenosis was relieved.The patient was followed up for six months and reported good defeca-tion.CONCLUSION The Y–Z DMR deformable magnetic ring is an excellent treatment strategy for patients with rectal stenosis and without enterostomy.

关键词： Anastomotic stenosis Colorectal cancer Magnetosurgery Magnetic compression technique Magnetic surgery clinic Case report

Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang Sheng-Lin Liu xiao-Lei Ai xiao-Wei Feng Bo Feng Zhuo Tian Ying-Fei Lin huan-Tao Chen Kai-Hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite plates.The rule of mixtures(ROM)for elongation was also addressed.The results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental ones.In contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM predictions.The plasticity of Mg-based bimetal plates increases with increasing sleeve fraction.This study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation

Appendiceal intussusception complicated by adenocarcinoma of the cecum:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1461-1466页

作者： Yu Long Yi-Ning Xiang Fei huang Lei Xu xiao-Yun Li Yun-huan Zhen Department of Colorectal Surgery The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guzihou ProvinceChina Department of Colorectal Surgery Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina Department of Pathology The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina

BACKGROUND Appendiceal intussusception is a pathological condition in which the appendix is inverted into the cecum,which may cause symptoms that resemble those of other gastrointestinal disorders and may induce intestinal obstruction.The rarity of this case presentation is the co-occurrence of appendiceal intussusception and cecal adenocarcinoma,a combination that to our knowledge has not previously been reported in the medical literature.This case provides new insights into the complexities of diagnosing and managing overlapping pathologies.CASE SUMMARY A 25-year-old woman presented with persistent periumbilical pain and bloody stools.An initial biopsy showed cecal cancer;however,subsequent colonoscopy and computed tomography findings raised the suspicion of appendiceal intussus-ception,which was later confirmed postoperatively.This unique case was charac-terized by a combination of intussusception and adenocarcinoma of the cecum.The intervention included a laparoscopic right hemicolectomy,which led to the histopathological diagnosis of mucinous adenocarcinoma with appendiceal intussusception.The patient recovered well postoperatively and was advised to initiate adjuvant chemotherapy.This case highlights not only the importance of considering appendiceal intussusception in the differential diagnosis,but also the possibility of appendicitis and the atypical presentation of neoplastic lesions.CONCLUSIONS Physicians should consider the possibility of appendiceal intussusception in cases of atypical appendicitis,particularly when associated with neoplastic presentation.

关键词： Appendiceal intussusception Appendicitis Cecal cancer Target signs Misdiagnosis Case report

A promising small molecule binding pocket in class B GPCRs: expanding potential for drug development

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Signal Transduction and Targeted Therapy 2023年第9期8卷 3888-3889页

作者： huan xiao Qian Sun Qiu Sun Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan University/West China School of NursingSichuan UniversityChengdu 610041China West China Medical Publishers West China HospitalSichuan UniversityChengdu 610041China

Recently,Xu et al.1 have published in Nature,solved the high-resolution structure of a small molecule agonist PCO371 and Gs bound human parathyroid hormone receptor 1(PTH1R)by cryo-electron microscopy.This study reveals a novel conserved small molecule agonist binding pocket of class B G protein-coupled receptors(GPCRs)and provides new insights into drug develop-ment for various therapeutic indications.GPCRs are a family of receptors with a seven transmembrane(7TM)domains that mediate various downstream signals by activating G proteins or recruitingβ-arrestins.As the largest family of cell membrane receptors encoded by the human genome,GPCRs are widely involved in human physiological and patholo-gical processes and have become the most important therapeutic targets.

关键词： expanding insight class

Stripping of aggregate from mortar in waste concrete heated by microwave: Mechanisms of differential-temperature stress and vapor expansion pressure

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 538-558页

作者： Yanping Sheng xiao huan Peizhen Hu Liangliang Li Ahmed Abdulakeem Zhoujing Ye Linbing Wang Yanping Yin School of Materials Science and Engineering Chang'an University Engineering Research Center of Transportation Materials Ministry of Education Chang'an University National Center for Materials Service Safety University of Science and Technology Beijing School of Environmental Civil Agricultural and Mechanical Engineering College of Engineering University of Georgia

Microwave heating, which is used for pre-treatment of concrete before it is comminuted,stands as a strong candidate for selective liberation of multiphase materials like concrete.This paper is concerned with the selective liberation of concrete's raw constituents(particularly aggregate) for recycling by considering the water content of concrete as a parameter of microwave heating for the first time. The deterioration law of the concrete's performance was characterized by the variation in the splitting tensile strength and relative dynamic modulus after heating by microwave at different water contents. Besides,tests were conducted to evaluate the performance of the interface transition zone(ITZ)between aggregate and mortar as well as to investigate the reasons for the stripping behavior of aggregate-mortar, which included the interface tensile strength test, temperature measurement, and porosity test. The deterioration law of splitting tensile strength and relative dynamic modulus revealed that the performance of concrete was subject to different degrees of damage depending on the water content. Furthermore, experimental results showed that interface bonding strength between aggregate and mortar was dramatically impaired, and a large temperature difference was generated between the aggregate and mortar during microwave heating. Meanwhile, the permeable pores increased considerably even when the specimens were dried. In the presence of water, the intactness of ITZ between aggregate and mortar was destroyed by microwave heating, and its performance was significantly lowered, which led to the occurrence of stripping behavior between aggregate and mortar. This was reaffirmed by the microstructure presented by scanning electron microscopy. Thus, the newly developed microwave pretreatment improved by providing appropriate water contents for concrete corresponding to different strength grades is a promising method for recycling aggregate from waste concrete.

关键词： Waste concrete Recycled aggregate Microwave heating Stripping behavior Differential-temperature stress Vapor expansion pressure