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Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU shi-peng YANG Wen-zhi GAO Min HU Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models

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World Journal of Gastroenterology 2024年第9期30卷 1164-1176页

作者： Yan-Li Jiang Juan Li peng-fei Zhang Feng-Xian Fan Jie Zou Pin Yang peng-fei Wang Shao-Yu Wang Jing Zhang Department of Magnetic Resonance Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Second Clinical School Lanzhou UniversityLanzhou 730030Gansu ProvinceChina Gansu Province Clinical Research Center for Functional and Molecular Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Department of Hepatology The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina MR Scientific Marketing Siemens HealthineersXi’an 710065Shaanxi ProvinceChina

BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver ***,its diagnostic performance is inconsistent among ***,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one *** To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic *** This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy *** participants underwent multi-b value *** main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and *** CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis *** areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was *** combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver *** combined index of CTRW paramet

关键词： Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis

Impairment of Autophagic Flux After Hypobaric Hypoxia Potentiates Oxidative Stress and Cognitive Function Disturbances in Mice

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Neuroscience Bulletin 2024年第1期40卷 35-49页

作者： Shuhui Dai Yuan Feng Chuanhao Lu Hongchen Zhang Wenke Ma Wenyu Xie Xiuquan Wu peng Luo Lei Zhang fei fei Zhou fei Xia Li Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi'an 710000China National Translational Science Center for Molecular Medicine and Department of Cell Biology Fourth Military Medical UniversityXi'an 710000China Department of Neurosurgery The Central Hospital of BaojiBaoji 721000China Department of Ophthalmology Xijing HospitalFourth Military Medical UniversityXi'an 710000China

Acute hypobaric hypoxic brain damage is a potentially fatal high-altitude *** plays a critical role in ischemic brain injury,but its role in hypo-baric hypoxia(HH)remains *** we used an HH chamber to demonstrate that acute HH exposure impairs autophagic activity in both the early and late stages of the mouse brain,and is partially responsible for HH-induced oxidative stress,neuronal loss,and brain *** autophagic agonist rapamycin only promotes the initiation of *** proteome analysis,a screen showed that protein dynamin2(DNM2)potentially regulates autophagic *** of DNM2 significantly increased the formation of autolysosomes,thus maintaining autophagic flux in combination with ***,the enhancement of autophagic activity attenuated oxidative stress and neurological deficits after HH *** results contribute to evidence supporting the conclusion that DNM2-mediated autophagic flux represents a new therapeutic target in HH-induced brain damage.

关键词： Autophagy-Proteomics Oxidative stress Hypobaric hypoxia-Brain injury

纳米氧化物对MH/Ni电池负极电化学性能影响的研究

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化学学报 2006年第10期64卷 1031-1035页

作者：邓超史鹏飞张森哈尔滨工业大学应用化学系哈尔滨150001 哈尔滨工程大学化工学院哈尔滨150001

采用纳米氧化铜作为添加剂掺杂制备MH/Ni电池负极,研究了氧化铜在电极内部的反应机理,考察了修饰后电极储备容量的变化,及电极的电化学性能,并应用EIS方法探讨了电极性能改善的作用机理.循环伏安测试表明,氧化铜在首次充电时被还原成铜... 详细信息

采用纳米氧化铜作为添加剂掺杂制备MH/Ni电池负极,研究了氧化铜在电极内部的反应机理,考察了修饰后电极储备容量的变化,及电极的电化学性能,并应用EIS方法探讨了电极性能改善的作用机理.循环伏安测试表明,氧化铜在首次充电时被还原成铜并沉积在合金颗粒表面.电化学测试表明,掺杂后合金电极的电化学性能显著提高.EIS分析表明,掺杂后合金电极的导电性提高,电化学活性增强.

关键词：纳米氧化铜 MH/Ni电池电化学性能电动车

Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens

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Journal of Animal Science and Biotechnology 2024年第1期15卷 295-312页

作者： Lianhua Zhang Junwei Ge fei Gao Min Yang Hui Li fei Xia Hongtong Bai Xiangshu Piao Zhiying Sun Lei shi Key Laboratory of Plant Resources Institute of BotanyChinese Academy of SciencesBeijing 100093China China National Botanical Garden Beijing 100093China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Rosemary extract(RE)has been reported to exert antioxidant ***,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically *** study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(P<0.05)Haugh unit and n-6/n-3 of egg yolk,serum superoxide dismutase(SOD)compared with *** significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 *** with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and *** with CON,RE supplementation decreased(P<0.05)total cholesterol(TC)***,RE100 and RE200 decreased(P<0.05)serum interleukin-6(IL-6)content compared with *** and RE200 increased jejunal m RNA expression of ZO-1 and Occludin compared with *** biomarkers of cecal microbiota and metabolite induced by RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely associated with Haugh unit,n-6/n-3,SOD,IL-6,and ***2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co ***,transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal *** Dietary supplementation with 2

关键词： Intestinal health Laying hens Microbiota Oviductal function Phytochemicals Production

Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

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World Journal of Gastroenterology 2024年第18期30卷 2418-2439页

作者： Xiao-Cong Zhou shi-Wei Guan fei-Yue Ke Gaurav Dhamija Qiang Wang Bang-fei Chen Medical University(Wenzhou Central Hospital) Wenzhou 325000Zhejiang ProvinceChina Department of Hepatobiliary Surgery The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Postgraduate Training Base Alliance of Wenzhou Medical University Wenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina School of International Studies Wenzhou Medical UniversityWenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Radiology The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Department of Colorectal Surgery The Affiliated Zhejiang HospitalZhejiang University School of Medicine(Zhejiang Hospital)Hangzhou 310000Zhejiang ProvinceChina

BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic ***,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical *** To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal *** We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal ***-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)*** difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a *** Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty *** logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery.

关键词： Nomogram Rectal cancer Laparoscopic operation Sphincter-preserving surgery Technical difficulty

基于最小化最大类内距离的面聚类网格分割算法

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上海交通大学学报 2005年第4期39卷 535-538页

作者：周洋严京旗施鹏飞上海交通大学图像处理与模式识别研究所上海200030

介绍了一种简单、有效的三维网格分割算法.该算法是基于最小化最大类内误差的聚类方法.先将表面网格转换成连接图,通过最短路径定义任意两个三角形之间的"距离",然后利用新的距离度量将传统的聚类算法应用到网格表面分割问题.提出的算... 详细信息

介绍了一种简单、有效的三维网格分割算法.该算法是基于最小化最大类内误差的聚类方法.先将表面网格转换成连接图,通过最短路径定义任意两个三角形之间的"距离",然后利用新的距离度量将传统的聚类算法应用到网格表面分割问题.提出的算法不仅确保使最大类内距离实现最小,而且可以确保每个类别的所有三角形都构成网格表面上单独的一片.提出了一种受限边界直化算法,极大改善了分割后的区域形状.实验表明,这种两步(最小化最大类内距离聚类和受限边界直化)的网格分割算法在区域平面性和区域形状方面都表现出了良好效果.

关键词：网格分割聚类平面度最小生成树

Xiao Tan San Jie Fang Hampers the Growth of Colon Cancer Stem Cells through the Wnt/β-catenin Signaling Pathway

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World Journal of Traditional Chinese Medicine 2024年第2期10卷 171-179页

作者： Yu-Qi Zhou Jun-fei Yuan Hong-shi Shen Ya-Ping Wang Han-fei shi De-Jian Pan Min Ye Department of Hematology and Oncology The 904^(th) Hospital of PLA Joint Logistic Support ForceWuxiJiangsuChina Department of Clinical Laboratory The 904^(th)Hospital of PLA Joint Logistic Support ForceWuxiJiangsuChina Department of Traditional Chinese Medicine Second Affiliated Hospital of Naval Medical UniversityShanghaiChina

Objective: The purpose of this research was to examine the potential anticancer properties of Xiao Tan San Jie Fang(XTSJF) and its potential mechanism of action against colorectal cancer. Materials and Methods: HCT116 cells were induced into HCT116 spheres in DMEM/F12 medium by treatment with epidermal growth factor + fibroblast growth factor + leukemia inhibitory factor + B27. The proliferation ability and stemness of HCT116 spheres was examined. Various concentrations of XTSJF were used to treat HCT116 spheres to observe the impact on proliferation, apoptosis, and expression of stem cell markers. Next, Wnt/β-catenin pathway-related factor proteins were detected. Results: The findings revealed that XTSJF suppressed cell growth and induced cell death in HCT116 cells in a dosage-dependent manner. Similarly, XTSJF promotes apoptosis, inhibits cell proliferation, prolongs survival, and maintains the expression of stem cells through the Wnt/-catenin/TCF4 axis. XTSJF also inhibits AKT activity and subsequently activates glycogen synthesis kinase-3β expression, inhibiting Wnt/beta-catenin pathway activity and downstream target gene transcript expression. The Wnt/β-catenin signaling pathway is inhibited by the XTSJF, leading to the suppression of colon cancer stem cell proliferation. Conclusion: Xiaotan Sanjie Prescription inhibited colon cancer stem cell growth through Wnt/β-catenin signaling pathway.

关键词： Apoptosis colorectal cancer proliferation traditional Chinese medicine Wnt/β-catenin signaling

Two-Dimensional Materials for Highly Efficient and Stable Perovskite Solar Cells

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Nano-Micro Letters 2024年第10期16卷 176-212页

作者： Xiangqian Shen Xuesong Lin Yong peng Yiqiang Zhang fei Long Qifeng Han Yanbo Wang Liyuan Han State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People's Republic of China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physical Science and TechnologyXinjiang UniversityUrumqi 830046People's Republic of China Special Division of Environmental and Energy Science College of Arts and SciencesKomaba Organization for Educational ExcellenceUniversity of TokyoTokyo 153-8902Japan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People's Republic of China College of Chemistry Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001People's Republic of China Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004People's Republic of China

Perovskite solar cells(PSCs)offer low costs and high power conversion ***,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders their practical *** the past few years,two-dimensional(2D)materials(e.g.,graphene and its derivatives,transitional metal dichalcogenides,MXenes,and black phosphorus)have been identified as a promising solution to solving these problems because of their dangling bond-free surfaces,layer-dependent electronic band structures,tunable functional groups,and inherent ***,recent progress of 2D material toward efficient and stable PSCs is summarized,including its role as both interface materials and *** discuss their beneficial effects on perovskite growth,energy level alignment,defect passivation,as well as blocking external *** particular,the unique properties of 2D materials to form van der Waals heterojunction at the bottom interface are ***,perspectives on the further development of PSCs using 2D materials are provided,such as designing high-quality van der Waals heterojunction,enhancing the uniformity and coverage of 2D nanosheets,and developing new 2D materials-based electrodes.

关键词： Perovskite solar cells Two-dimensional materials Interface engineering Van der Waals heterojunction Electrodes