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MODIFIED NEWTON＇S ALGORITHM FOR COMPUTIng THE GROUP INVERSES OF SIngULAR TOEPLITZ MATRICES

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Journal of Computational Mathematics 2006年第5期24卷 647-656页

作者： Jian-feng Cai Michael K. ng yi-min Wei Department of Mathematics The Chinese University of Hong Kong Hong Kong Department of Mathematics Hong Kong Baptist University Hong Kong School of Mathematical Sciences Fudan University Shanghai 200433 China ~ Key Laboratory of Mathematics for Nonlinear Sciences (Fudan University) Ministry of Education

Newton＇s iteration is modified for the computation of the group inverses of singular Toeplitz matrices. At each iteration, the iteration matrix is approximated by a matrix with a low displacement rank. Because of the displacement structure of the iteration matrix, the matrix-vector multiplication involved in Newton＇s iteration can be done efficiently. We show that the convergence of the modified Newton iteration is still very fast. Numerical results are presented to demonstrate the fast convergence of the proposed method.

关键词： Newton's iteration Group inverse Toeplitz matrix Displacement rank.

Hydrogen generation from ammonia electrolysis on bifunctional platinum nanocubes electrocatalysts

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Journal of Energy Chemistry 2020年第8期29卷 234-240,I0009页

作者： Hui-y.ng Sun Guang-Rui Xu Fu-min Li Qi ng-Li ng Hong Pu-Jun Jin Pei Chen yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education)Shaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710062ShaanxiChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'an 710062ShaanxiChina

The ammonia electrolysis is a highly efficient and energy-saving method for ultra-pure hydrogen generation, which highly relies on electrocatalytic performance of electrocatalysts. In this work, high-quality platinum(Pt) nanocubes(Pt-NCs) with 4.5 nm size are achieved by facile hydrothermal synthesis. The physical morphology and structure of Pt-NCs are exhaustively characterized, revealing that Pt-NCs with special {100} facets have excellent uniformity, good dispersity and high crystallinity. Meanwhile, the electrocatalytic performance of Pt-NCs for ammonia electrolysis are carefully investigated in alkaline solutions, which display outstanding electroactivity and stability for both ammonia electrooxidation reaction(AEOR) and hydrogen evolution reaction(HER) in KOH solution. Furthermore, a symmetric Pt-NCs||Pt-NCs ammonia electrolyzer based on bifunctional Pt-NCs electrocatalyst is constructed, which only requires 0.68 V electrolysis voltage for hydrogen generation. Additionally, the symmetric Pt-NCs||Pt-NCs ammonia electrolyzer has excellent reversible switch capability for AEOR at anode and HER at cathode, showing outstanding alternating operation ability for ammonia electrolysis.

关键词： Ammonia electrolysis Water electrolysis Ammonia oxidation reaction Hydrogen evolution reaction Platinum nanocubes

Structure regulation for ultra-high luminescence quantum yield lanthanide complex and simultaneous detection of cancer marker and ferrous ion

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Journal of Rare Earths 2021年第10期39卷 1194-1203,I0002页

作者： min Liu Zhifeng Li Jianhui Xiong yefei Jiang Ting Tang Jinkai Qiu Junwei yao Seik Weng ng Chenghui Zeng Research Center for Ultra Fine Powder Materials Key Laboratory of Functional Small Organic MoleculeMinistry of Education and Jiangxi's Key Laboratory of Green ChemistryCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022China School of Chemical Engineering and Technology Tianshui Normal UniversityTianshui 741001China UCSI University CherasKuala LumpurMalaysia

The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great *** this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is designed to disrupt the polymeric lanthanide MOFs(LnMOFs,[Ln(CHO_(2))_(3)]n,Ln=Tb,la;Eu,1 b,CHO_(2)=formic acid) {[Ln(CHO_(2))_(4)·(C_(2) H_(8) N)]n,Ln=y,2 a;Gd,2 b;Dy,2 c,C_(2)H_(8) N=dimethylamine}) into a soluble mononuclear species [Ln(phen)_(2)(NO_(3))_(3),Ln=Tb,3 a;Eu,3 b] as well as to provide an antenna for efficient photons absorption,resulting in an ultra-high luminescence quantum yield(Qy,90%) europium *** luminescence Qy is among the highest record of monomeric(zero-dimensional) lanthanide ***,mononuclear Tb3+complex(3 a) functions as a multiplex sensor towards both Fe^(2+)and cancer marker of 5-hydroxyindole-3-acetic acid(5-HIAA).Importantly,the limit of detection(LOD)for sensing 5-HIAA is an ultra-sensitive value of 1 × 10 s mol/L,which is even lower than that necessary for the early diagnosis of carcinoid *** interestingly,sensing results in simulated urine reveals that 3 a has potential application for early diagnosis in the clinic.

关键词： Ultra-high luminescence quantum yield Lanthanide complex Simultaneous detection Cancer marker Ferrous ion Rare earths

踝关节骨折术后踝穴冠状位角度波动与关节功能恢复的关系

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中国组织工程研究 2025年第9期29卷 1820-1826页

作者：刘琰王铠吴敏泰州市中医院骨科江苏省泰州市225300

背景:踝关节骨折术后的踝穴形态指标会出现相应变化,而其中踝穴冠状位角度变化与踝关节的功能恢复之间存在一定的关联,既往研究大多探讨患者术后踝穴高度恢复,故研究踝关节骨折术后踝穴冠状位角度的波动与关节功能恢复的相关性具有一定... 详细信息

背景:踝关节骨折术后的踝穴形态指标会出现相应变化,而其中踝穴冠状位角度变化与踝关节的功能恢复之间存在一定的关联,既往研究大多探讨患者术后踝穴高度恢复,故研究踝关节骨折术后踝穴冠状位角度的波动与关节功能恢复的相关性具有一定参考意义。目的:探讨踝关节骨折术后踝穴冠状位角度变化对关节功能恢复的影响。方法:纳入进行手术治疗的86例踝关节骨折患者为研究对象,根据末次随访美国骨科足踝外科协会踝-后足评分结果分为优良组(n=45)和可差组(n=41),比较两组患者的一般资料。根据踝关节的踝穴位及侧位X射线片对比术后患者患侧和健侧的踝穴形态指标:包括踝穴宽度和深度、冠状位角度及矢状位角度,以及上述指标患侧和健侧之间的差值,并进一步进行组内比较分析。构建联合模型,利用Cox回归分析评估冠状位角度波动与关节功能恢复情况的关系。利用最小绝对收缩选择算子回归法和多因素Logistic回归分析影响患者关节功能恢复的危险因素。按踝穴冠状位角度从低到高等分为5分位数组(Q1-Q5),比较5组患者的临床资料特征,并采用多因素Logistic回归分析踝穴冠状位角度变化与关节功能恢复不良风险的相关性,建立限制性立方样条Logistic回归模型分析其剂量-反应关系。建立回归方程y=1-1/(1+e^(-z))预测模型并进行验证。结果与结论:①患者患侧的踝穴宽度和深度、冠状位角度及矢状位角度均显著大于健侧(P均<0.05);且与优良组患者相比,可差组患者踝穴宽度差值、深度差值、冠状位角度差值及矢状位角度差值均更大(P<0.05);②联合模型显示无论冠状位角度是否在正常范围内,冠状位角度每纵向增加1˚,关节功能恢复不良的风险增加3%;③最小绝对收缩选择算子回归和多因素Logistics回归分析显示,调整潜在混杂因素后发现年龄过大、早期功能锻炼缺乏、无跟骨牵引、内固定物未取出、术后并发症、踝冠状位角度增大均为影响患者关节功能恢复的独立危险因素(P<0.05);④术后3个月内的冠状位角度与关节功能恢复效果不良风险存在独立相关性(OR=1.57,95%CI:1.38-1.76,P=0.002),且术后各时间段冠状位角度从低到高5分位数组趋势性检验差异有统计学意义(P趋势<0.001);⑤限制性立方样条模型分析显示,男性或女性的踝穴冠状位角度变化与关节功能恢复效果不良风险均不存在非线性关系;经Bootstrap自抽样,预测模型区分度、准确度较好;⑥提示踝关节骨折术后踝穴冠状位角度减小对关节功能恢复起到明显的促进作用,因此在踝关节骨折术后重点检测踝穴冠状位角度有助于了解患者关节功能恢复情况。

关键词：踝关节骨折踝穴冠状位角度关节功能 Logistic回归分析

Effect of CO2 pneumoperitoneum on the expression of the chemokine receptors CXCR4 and CCR7 in colorectal carcinoma cells in vitro

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Chinese Medical Journal 2013年第24期126卷 4747-4751页

作者： y.ng Chun-kang LI Guo-dong y.ng min-gang XU Ke Department of Abdominal Surgery Fujian Provincial Cancer Hospital Fuzhou Fujian 350014 China Department of Oncology Guizhou Cancer Hospital GuiyangGuizhou 550004 China Provincial Clinical Coliege Fujian Medical University FuzhouFujian 350014 China

Background The ability of pneumoperitoneum in laparoscopic surgery to promote proliferation and metastasis of colorectal cancer has become a focus of research in the field of minimally invasive surgery. The aim of this research was to investigate the effect of CO~ pneumoperitoneum under different pressures and exposed times on the expression of chemokine receptors in colorectal carcinoma cells. Methods We constructed an in vitro pneumoperitoneum model. SW480 colon carcinoma cells were exposed to CO2 pneumoperitoneum under different pressures （6, 9, 12, and 15 mmHg） for 1, 2, and 4 hours. These cells were then cultivated under the same conditions as normal SW480 colon carcinoma cells without CO= pneumoperitoneum （control group）, treated at 37℃, and 5% CO2. The expression of the chemokine receptors CXC receptor 4 （CXCR4） and chemokine C receptor 7 （CCR7） was detected by immunocytochemistry and reverse transcriptase polymerase chain reaction after being cultivated for 0, 24, 48, and 72 hours. Results Immunocytochemistry showed that CXCR4 expression in SW480 cells was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups for the same exposure times compared with controls （P 〈0.05）. CCR7 expression in SW480 cells was significantly decreased in the 12 and 15 mmHg CO2 pneumoperitoneum- treated groups compared with controls （P 〈0.05）. CXCR4 and CCR7 expression increased up to the level of the control group after 24 and 48 hours （P 〉0.05）. If the CO2 pneumoperitoneum pressure increased, CXCR4 and CCR7 expression decreased at all exposure times. If the CO2 pneumoperitoneum exposure time prolonged, there were no significant differences in CXCR4 and CCR7 expression under the same pressure. Under all exposure times, CXCR4 and CCR7 mRNA expression was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups （P 〈0.05） compared with controls, and it increased up to the level of controls after being cultivated for 48

关键词： colorectal neoplasm, C02 pneumoperitoneum chemokine receptor, CXC receptor 4, chemokine C receptor 7

Sodium-Coordinated Polymeric Phthalocyanines as Stable High-Capacity Organic Anodes for Sodium-Ion Batteries

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Energy & Environmental Materials 2023年第4期6卷 22-30页

作者： Jeongyeon Lee yoonbin Kim Soy.ng Park Kang Ho Shin Gun Jang min Jun Hwang Daekyu Kim Ky.ng-Ah min Ho Seok Park By.ngchan Han Dennis K.P.ng Lawrence yoon Suk Lee Department of Applied Biology and Chemical Technology and Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloon Hong Kong SAR China Department of Chemistry The Chinese University of Hong KongShatinNew Territories Hong Kong SAR China Convergence Research Center for Energy and Environmental Sciences Sungkyunkwan UniversitySuwon Korea Department of Chemical and Biomolecular Engineering Yonsei UniversitySeoul Korea School of Chemical Engineering Sungkyunkwan UniversitySuwon Korea

Sodium-ion batteries(SIBs)have attracted considerable interest as an alternative to lithium-ion batteries owing to their similar electrochemical performance and superior long-term cycle *** materials are regarded as promising anode materials for constructing SIBs with high capacity and good ***,utilization of organic materials is rather limited by their low energy density and poor stability at high current *** overcome these limitations,we utilized a novel polymeric disodium phthalocyanines(pNaPc)as SIB anodes to provide stable coordination sites for Na ions as well as to enhance the stability at high current *** vary.ng the linker type during a one-pot cyclization and polymerization process,two pNaPc anodes with O-(O-pNaPc)and S-linkers(S-pNaPc)were prepared,and their structural and electrochemical properties were *** O-pNaPc binds Na ions with a lower binding energy compared with S-pNaPc,which leads to more facile Na-ion coordination/dissociation when engaged as SIB *** use of O-pNaPc significantly improves the redox kinetics and cycle stability and allows the fabrication of a full cell against Na_(3)V_(2)(PO_(4))_(2)F_(3)/C cathode,which demonstrates its practical application with high energy density(288 Wh kg^(-1))and high power density(149 W kg^(-1)).

关键词： coordination chemistry organic anode phthalocyanine polymerization sodium ion battery

An Overview of the Expert Consensus on the Prevention and Treatment of Gaming Disorder in China(2019 Edition)

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Neuroscience Bulletin 2020年第7期36卷 825-828页

作者： yu-Tao Xiang yu Jin Ling Zhang Lu Li Gabor S.Ungvari Chee H.ng min Zhao Wei Hao Unit of Psychiatry Institute of Translational MedicineFaculty of Health SciencesUniversity of MacaoMacao 999078China Center for Cognition and Brain Sciences University of MacaoMacao 999078China The National Clinical Research Center for Mental Disorders&Beijing Key Laboratory of Mental Disorders Beijing Anding Hospital&the Advanced Innovation Center for Human Brain ProtectionCapital Medical UniversitySchool of Mental HealthBeijing 100088China The Affiliated Brain Hospital of Guangzhou Medical University(Guangzhou Huiai Hospital) Guangzhou 510370China 不详

Gaming disorder has gained considerable attention worldwide,including in China[1],where epidemiological surveys have found that its prevalence is as high as 17%[2].The Bureau of Disease Control and Prevention run by the National Health and Health Commission in China recently released an expert consensus[2]that systematically describes the definition,clinical presentation,assess-assessment,diagnosis,treatment,rehabilitation,and related areas of gaming disorder.

关键词： gained Expert diagnosis

CT features of exophthalmos in Chinese subjects with thyroid-associated ophthalmopathy

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 146-149页

作者： Zhi-Jia Fang Jenny y.Zhang Wei-min He Department of Radiology West China Hospital of Sichuan University University of Illinois at Chicago Department of Ophthalmology West China Hospital of Sichuan University

AIM: To investigate computed tomography (CT) features of exophthalmos in Chinese subjects with thyroid-associated ophthalmopathy (TAO). METHODS: A total of 605 eyes of 325 patients with exophthalmos due to TAO were classified as grade Ⅰ (mild exophthalmos) or Ⅱ (severe exophthalmos) based on orbital CT imaging. The increased orbital volume features, such as changes from extraocular muscles, orbital fat, or both, were analyzed. RESULTS: A total of 605 eyes were analyzed, among them 62.98% presented grade Ⅰ exophthalmos, while 36.02% showed grade Ⅱ exophthalmos. In grade Ⅰ, 56.69% showed orbital fat change, and in grade Ⅱ, 89.29% exhibited extraocular muscle enlargement. CONCLUSION: Orbital fat and extraocular muscle enlargement are likely to be observed on CTs of subjects with mild and severe exophthalmos, respectively. Our results suggest that CT findings may guide TAO clinical therapy recommendations and prognosis.

关键词： thyroid-associated ophthalmopathy (TAO) computed tomography (CT) exophthalmos

Characterization of Various Microalgae for Biodiesel Fuel Production

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材料科学与工程（中英文A版） 2011年第1X期1卷 80-86页

作者： ng Ching yin Zahira yaakob Ehsan Ali Aung min min ng Sheng Wa Department of Chemical and Process Faculty of Engineering and Environment Built Universiti Kebangsaan Malaysia Bangi 43600Malaysia