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Chemiluminescence Sensor for the Determination of Hydroxylamine by Electrostatically Immobilizing Luminol and Periodate 被引量:1
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作者 ZHANG Si chun ZHOU Guo jun JU Huang xian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期155-159,共5页
A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion exch... A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion exchange resin respectively. Hydroxylamine was sensed by its enhancing effect on the weak CL reaction between luminol and periodate, which were eluted from the ion exchange column. The response of the sensor to hydroxylamine was linear in the concentration range of 8.0×10^(-8)-2.0×10^(-6)mol/L with a detection limit of 4.0×10^(-8)mol/L hydroxylamine(3σ).The relative standard deviation(RSD) was 2.0% for 9 repetitive determinations at a hydroxylamine concentration of 5.0×10^(-7) mol/L. The sensor could be reused for over 400 times with a good reproducibility and was used to determine hydroxylamine in wastewater. 展开更多
关键词 Chemical sensor CHEMILUMINESCENCE LUMINOL periodate HYDROXYLAMINE
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INFLUENCE OF MOLECULAR WEIGHT AND PERIODATE-MODIFICATION OF β-D-GLUCANS FROM PORIA COCOS SCLEROTIUM ON ANTITUMOR ACTIVITIES 被引量:1
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作者 丁琼 张俐娜 曾凡波 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第1期62-66,共5页
In this work, influence of molecular weight and periodate modification ofβ-D-glucans isolated from Poria cocos sclerotium on the antitumor activities against Sar-coma 180 and Ehrlich ascites carcinoma (EAC) tumor was... In this work, influence of molecular weight and periodate modification ofβ-D-glucans isolated from Poria cocos sclerotium on the antitumor activities against Sar-coma 180 and Ehrlich ascites carcinoma (EAC) tumor was studied. The results show thattwo glucans PC3 (linear β-(1→3)-D-glucan) and PC4 [β-(1→3)-D-glucan with a fewof branches and glucuronic acid] are devoid of antitumor activity. However, when theglucans were modified by periodate oxidation, borohydride reduction and mild hydrolysisor partially hydrolysis, the derivatives have obvious antitumor activities. The decreasein molecular weight of glucans after periodate modification hardly affects their antitumoractions, but on the other hand, the decrease of molecular weight without periodate modi-fication could lead to an enhancement of the antitumor activities. Moreover, the glucansand these derivatives have much higher enhancement ratios of body weight of mice thanthat of 5-Fluorouracil (5-Fu), suggesting that they are less toxic than 5-Fu. 展开更多
关键词 Poria cocos sclerotium POLYSACCHARIDE periodate modification Molecular weight Antitumor activity
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Oxidizing Cellulose to 2,3-Dialdehyde Cellulose by Sodium Periodate 被引量:1
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作者 孟舒献 冯亚青 +2 位作者 梁足培 付强 张恩仲 《Transactions of Tianjin University》 EI CAS 2005年第4期250-254,共5页
Study on oxidizing cellulose to 2.3-dialdehyde cellulose by sodium periodate (NalO4) was carried out. The effects of reaction conditions such as pH of solution, temperature, oxidant concentration, oxidation time. th... Study on oxidizing cellulose to 2.3-dialdehyde cellulose by sodium periodate (NalO4) was carried out. The effects of reaction conditions such as pH of solution, temperature, oxidant concentration, oxidation time. the particle size of 2,3-dialdehyde cellulose and alkali treatment temperature on the dialdehyde concentration ot cellulose were investigated in detail, The results show that the aldehyde group content was created while reaction temperature and alkali treatment temperature increased. The most principal factors affecting the aldehyde group content of 2,3-dialdehyde cellulose were found out and the best oxidation conditions were as follows: the pH was 2. the reaction temperature was 45℃. the mass ratio of cellulose to NalO4 was 1/2, the reaction time was 4 h, the alkali treatment temperature was 70℃ and smaller particle size was 0.80 mm. 展开更多
关键词 CELLULOSE oxidation: 2.3-dialdehyde cellulose sodium periodate
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Enhanced chemiluminescence from reactions between CdTe/CdS/ZnS quantum dots and periodate 被引量:2
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作者 Yu Li Yong-Zan Zheng +3 位作者 Ding-Kun Zhang Hai-Fang Li Yuan Ma Jin-Ming Lin 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期184-188,共5页
A novel chemiluminescence(CL) performance of CdTe/CdS/ZnS quantum dots(QDs) with periodate(KIO_4) was studied.Effects of concentration and pH on the CL system were investigated.Electron spin resonance(ESR) and... A novel chemiluminescence(CL) performance of CdTe/CdS/ZnS quantum dots(QDs) with periodate(KIO_4) was studied.Effects of concentration and pH on the CL system were investigated.Electron spin resonance(ESR) and the effects of radical scavenger analysis were employed for identification of intermediate species.The CL spectra for this system showed only one maximum emission peak centered around 620 nm,which was similar with photoluminescence(PL) spectra of CdTe/CdS/ZnS QDs.The CL of CdTe/CdS/ZnS QDs was induced by direct chemical oxidation and the possible mechanism could be explained by radiative recombination of injected holes and electrons.This investigation not only provided new sight into the optical characteristics of CdTe/CdS/ZnS QDs,but also broadened their potential optical utilizations. 展开更多
关键词 Chemiluminescence CdTe/CdS/ZnS quantum dots periodate Electron injection Hole injection
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Synthesis and Characterization of the Alkali Periodate Complexes of Rare Earths: M_2LnIO_6·xH_2O
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作者 杨瑛 杨汝栋 李英 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第4期272-275,共4页
The novel eomplexes of alkali and rare earth metal with periodate have been prepared for the first time. Chemical analysis indicates that the composition of the complexes is M_2LnIO_6·xH_2O(M=Li,Na,K;Ln=Pr, Tb),a... The novel eomplexes of alkali and rare earth metal with periodate have been prepared for the first time. Chemical analysis indicates that the composition of the complexes is M_2LnIO_6·xH_2O(M=Li,Na,K;Ln=Pr, Tb),and all of the complexes have been characterized by UV-Visible,IR spectroscopic studies,susceptibility measurements and thermal analysis. 展开更多
关键词 Alkali periodate complexes PRASEODYMIUM TERBIUM SYNTHESIS
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Periodate Oxidation of a Ternary Complex of Nitrilotriacetatochromium(III) Involving ß-Alanine as Co-Ligand
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作者 Hassan A. Ewais Ahmed H. Abdel-Salam +1 位作者 Amal S. Basaleh Mohamed A. Habib 《Open Journal of Inorganic Chemistry》 2018年第4期91-104,共14页
The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = &#223;-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35&... The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = &#223;-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35°C under pseudo-first order conditions, >>?[complex]. Reaction obeyed first order dependence with respect to and [Cr(III)], and the rate of reaction increases with increasing of pH for the range 3.40 - 4.45. Experimentally, the mechanism of this reaction is found to be consistent with the rate law in which the hydroxo species, [CrIII(NTA)(Ala)(OH)]2- is considerably much more reactive than their conjugate acid. ΔH* and ΔS* have been calculated. It is proposed that electron transfer occurs through an inner-sphere mechanism via coordination of to chromium(III). 展开更多
关键词 Nitrilotriacetatochromium(III) TERNARY Complex periodate Oxidation Inner-Sphere Mechanism THERMODYNAMIC Activation Parameters
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Enhanced anaerobic digestion of waste activated sludge with periodate-based pretreatment 被引量:1
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作者 Haixiao Guo Lixin Tian +5 位作者 Yufen Wang Kaixin Zheng Jiaqi Hou Yingxin Zhao Tingting Zhu Yiwen Liu 《Environmental Science and Ecotechnology》 SCIE 2023年第1期75-85,共11页
The potential of periodate(PI)in sludge anaerobic digestion is not tapped,although it has recently attracted great research interest in organic contaminants removal and pathogens inactivation in wastewater treatment.T... The potential of periodate(PI)in sludge anaerobic digestion is not tapped,although it has recently attracted great research interest in organic contaminants removal and pathogens inactivation in wastewater treatment.This is the first work to demonstrate significant improvement in methane generation from waste activated sludge(WAS)with PI pretreatment and to provide underlying mechanisms.Biochemical methane potential tests indicated that methane yield enhanced from 100.2 to 146.3 L per kg VS(VS,volatile solids)with PI dosages from 0 to 100 mg per g TS(TS,total solids).Electron spin resonance showed PI could be activated without extra activator addition,which might be attributed to the native transition metals(e.g.,Fe2t)in WAS,thereby generating hydroxyl radical(-OH),superoxide radicals(-O2-),and singlet oxygen(1O2).Further scavenging tests demonstrated all of them synergistically promoted WAS disintegration,and their contributions were in the order of-O2->-OH>1O2,leading to the release of substantial biodegradable substances(i.e.,proteins and polysaccharides)into the liquid phase for subsequent biotransformation.Moreover,fluorescence and ultraviolet spectroscopy analyses indicated the recalcitrant organics(especially lignocellulose and humus)could be degraded by reducing their aromaticity under oxidative stress of PI,thus readily for methanogenesis.Microbial community analysis revealed some microorganisms participating in hydrolysis,acidogenesis,and acetoclastic methanogenesis were enriched after PI pretreatment.The improved key enzyme activities and up-regulated metabolic pathways further provided direct evidence for enhanced methane production.This research was expected to broaden the application scope of PI and provide more diverse pretreatment choices for energy recovery through anaerobic digestion. 展开更多
关键词 Energy recovery Anaerobic digestion Recalcitrant organics Free radicals periodate
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Flow-injection Chemiluminescence Sensor for the Determination of Gallic Acid by Immobilizing Luminol and Periodate on Anion-exchange Resin
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作者 张四纯 周国俊 鞠熀先 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2002年第10期1049-1054,共6页
A novel chemiluminescence (CL) sensor for the determination of gallic acid combined with flow injection analysis was developed by electrostatically immobilizing luminol and periodate on anion-exchange resins respectiv... A novel chemiluminescence (CL) sensor for the determination of gallic acid combined with flow injection analysis was developed by electrostatically immobilizing luminol and periodate on anion-exchange resins respectively. Gallic acid was sensed by its enhancing effect on the weak CL reaction between luminol and periodate, which were eluted from the ion exchange column. The possible reaction mechanism of the CL system was suggested and discussed. The response of the sensor to gallic acid concentration was linear over the range of 8.0×10 -9-1.0×10 -6 mol/L with a detection limit of 6.5×10 -9 mol/L (3σ). The relative standard deviation (RSD) for 7 repetitive determinations of gallic acid (1.0×10 -7 mol/L) was 1.8%. The sensor could be used for over 400 times determination with a good reproducibility. 展开更多
关键词 chemiluminescence sensor gallic acid LUMINOL periodate flow-injection analysis
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Effects of some Nitrogen Bases on the Oxygenation of Tetralin with Sodium Periodate Catalyzed by Manganese(Ⅲ)meso- Tetraphenylporphyrin as a Model Compound of Cytochrome P-450
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作者 REZA, Tayebee 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第7期1031-1035,共5页
The effect of some nitrogen bases on the oxygenation of tetralin by sodium periodate, catalyzed by Mn(TPP)OAc, was evaluated. A series of eight bases, including imidazole, pyridine, and quinuclidine, was used. Bindi... The effect of some nitrogen bases on the oxygenation of tetralin by sodium periodate, catalyzed by Mn(TPP)OAc, was evaluated. A series of eight bases, including imidazole, pyridine, and quinuclidine, was used. Binding of axial ligand to the four-coordinate Mn(Ⅲ)-center influenced the efficiency and selectivity of the catalytic oxygenation system. 展开更多
关键词 nitrogen donor sodium periodate oxidation manganese porphyrin TETRALIN
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Potential role of astrocyte on gamma-aminobutyric acid tone regulation during developmental period
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作者 Erva Ozkan Wuhyun Koh 《Neural Regeneration Research》 2026年第3期1118-1119,共2页
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte... The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time. 展开更多
关键词 early developmental period developmental period brain cells neuronal proliferation synapse formation gamma aminobutyric acid ASTROCYTE GABA
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Enhanced recovery after surgery-based recovery room nursing improves perioperative safety in gastrointestinal tumor surgery
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作者 Wan-Qi Zhong Su Wu +6 位作者 Ru-Xin Jiang Shao-Ru Chen Dan-Yang Li Jun Zhou Jiang-Xia Wu Ruo-Jing Zeng Hui Zhi 《World Journal of Gastrointestinal Oncology》 2026年第1期211-220,共10页
BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and... BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and high postoperative complication rates,which threaten patient safety and functional outcomes.Enhanced recovery after surgery(ERAS)principles have been shown to improve perioperative outcomes through evidence-based,multidisciplinary care pathways.Despite its widespread adoption,there is a paucity of research focusing specifically on optimizing ERAS-guided nursing processes in the post-anesthesia care unit(PACU)and evaluating its impact on perioperative safety in patients undergoing GI tumor surgery.This study aimed to investigate whether an ERASbased PACU nursing protocol could enhance recovery,reduce complications,and improve patient safety in this surgical population.AIM To explore the impact of optimizing the recovery room nursing process based on ERAS on the perioperative safety of patients with GI tumors.METHODS A total of 260 patients with GI tumors who underwent elective surgeries under general anesthesia in our hospital from August 2023 to August 2025 and were then observed in the recovery unit(PACU)were selected.They were randomly divided into the observation group(the PACU nursing process was optimized based on ERAS)and the control group(the conventional PACU nursing process was adopted)by the random number grouping method,with 130 cases in each group.The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,time of leaving the room after tube removal,retention time in the recovery room,occurrence of complications,satisfaction and readmission rate were compared between the two groups after entering the room.Compare the occurrence of adverse events in the PACU nursing process between the two groups.RESULTS The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,retention time in the recovery room,total incidence of complications and readmission rate in the observation group were significantly lower than those in the control group,and the satisfaction rate was higher than that in the control group(P<0.05).The occurrence of adverse events in the PACU nursing process in the observation group was lower than that in the control group(P<0.05).CONCLUSION Optimizing the PACU nursing process based on ERAS can effectively accelerate the recovery process of patients undergoing GI tumor surgery,reduce adverse events,improve nursing satisfaction,and at the same time,lower the incidence of adverse events in the PACU nursing process,providing a more refined management basis for clinical practice. 展开更多
关键词 Enhanced recovery after surgery Recovery room NURSING Gastrointestinal tumors Perioperative period
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番红砗磲生物钟基因Cryptochrome和Period克隆鉴定及光照相关性分析
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作者 杨文红 南祎晗 +4 位作者 李萌 刘春胜 杨毅 於锋 顾志峰 《渔业科学进展》 北大核心 2025年第4期153-167,共15页
生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基... 生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基因Cryptochrome和Period的编码区进行了克隆和特征分析,继而开展了其组织特异性和不同光照周期下的表达节律性研究。结果显示,Cryptochrome编码区碱基序列长1641 bp,编码546个氨基酸,理论等电点为6.08,分子量为62.98 kDa;Period编码区碱基序列长4386 bp,编码1461个氨基酸,理论等电点为6.14,分子量为164.99 kDa;Hdock互作模式研究结果显示,2个蛋白可形成异二聚体,结合能为–279.88 kcal/mol。组织表达分析显示,Cryptochrome和Period在7个组织中均有表达,其中,外外套膜、内外套膜、鳃和闭壳肌相对表达量较高(Cryptochrome在心脏中亦有较高表达量)。Cryptochrome和Period基因在外外套膜、内外套膜、鳃和闭壳肌中均昼夜变化,并呈现振荡表达的规律。在内、外外套膜中,Cryptochrome和Period基因分别在光照后1 h和光照前2 h表达量达到最高,且均随光照周期的推移(光照时间07:00~19:00推迟至09:00~21:00)而推移;在鳃组织中,正常光周期处理的Cryptochrome和Period基因均在光照前1 h表达量达到最高,当光照延迟2 h后,2个基因的最高表达时间推至光照后1 h;与之相反,闭壳肌中Cryptochrome和Period基因在08:00左右表达量最高,且未随光照延迟而发生变化。综上,本研究首次克隆获得番红砗磲2个关键生物钟基因Cryptochrome和Period,初步验证了这2个基因在主要组织表达的昼夜节律性,结果对揭示番红砗磲行为、生理节律和光照适应机制具有重要意义。 展开更多
关键词 番红砗磲 Cryptochrome和Period 昼夜节律 表达规律
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Circadian disruption by simulated shift work aggravates periodontitis via orchestrating BMAL1 and GSDMD-mediated pyroptosis 被引量:2
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作者 Yazheng Wang Rui Li +6 位作者 Qingyuan Ye Dongdong Fei Xige Zhang Junling Huang Tingjie Liu Jinjin Wang Qintao Wang 《International Journal of Oral Science》 2025年第1期122-132,共11页
Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift w... Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift work-related circadian disruption functions in periodontitis remains unknown.Herein,we employed a simulated shift work model constructed by controlling the environmental light-dark cycles and revealed that shift work-related circadian disruption exacerbated the progression of experimental periodontitis.RNA sequencing and in vitro experiments indicated that downregulation of the core circadian protein brain and muscle ARNT-like protein 1(BMAL1)and activation of the Gasdermin D(GSDMD)-mediated pyroptosis were involved in the pathogenesis of that.Mechanically,BMAL1 regulated GSDMD-mediated pyroptosis by suppressing NOD-like receptor protein 3(NLRP3)inflammasome signaling through modulating nuclear receptor subfamily 1 group D member 1(NR1D1),and inhibiting Gsdmd transcription via directly binding to the E-box elements in its promoter.GSDMD-mediated pyroptosis accelerated periodontitis progression,whereas downregulated BMAL1 under circadian disruption further aggravated periodontal destruction by increasing GSDMD activity.And restoring the level of BMAL1 by circadian recovery and SR8278 injection alleviated simulated shift work-exacerbated periodontitis via lessening GSDMD-mediated pyroptosis.These findings provide new evidence and potential interventional targets for circadian disruption-accelerated periodontitis. 展开更多
关键词 BMAL1 NLRP3 PERIOD
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An Improved Repetitive-Control System Using a Complex-Coefficient Filter 被引量:1
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作者 Qicheng Mei Jinhua She +1 位作者 Fei Long Yanjun Shen 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期282-284,共3页
Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter us... Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter used in the conventional repetitive controller(CRC), the complex-coefficient filter causes less change in the phase and amplitude of a signal at the frequencies of the periodic signal, especially at the fundamental frequency, when the two filters have the same cutofffrequency. 展开更多
关键词 improved repetitive controller irc periodic signals repetitive control system complex coefficient filter tracking performance conventional repetitive controller crc periodic signal enhance tracking performance
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Peaked traveling wave solutions of the modified highly nonlinear Novikov equation 被引量:1
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作者 LI Hui-jun WEN Zhen-shu LI Shao-yong 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期375-394,共20页
In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system w... In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system with three singular straight lines,and derive all possible phase portraits under corresponding parameter conditions.Then we show the existence and dynamics of two types of peaked traveling wave solutions including peakons and periodic cusp wave solutions.The exact explicit expressions of two peakons are given.Besides,we also derive smooth solitary wave solutions,periodic wave solutions,compacton solutions,and kink-like(antikink-like)solutions.Numerical simulations are further performed to verify the correctness of the results.Most importantly,peakons and periodic cusp wave solutions are newly found for the equation,which extends the previous results. 展开更多
关键词 modified highly nonlinear Novikov equation bifurcation dynamics peakons periodic cusp wave solutions
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New Features and New Challenges of U.S.-Europe Relations Under Trump 2.0 被引量:1
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作者 Zhao Huaipu 《Contemporary World》 2025年第3期47-52,共6页
During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 202... During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 2024 presidential election of the United States has plunged the U.S.-Europe relations into more gloomy waters,ushering in a more complex and turbulent period of adjustment. 展开更多
关键词 new features turbulent period Trump U S Europe relations presidential election new challenges UNCERTAINTIES transatlantic alliance
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Ferroelectric domain engineering of Lithium niobate 被引量:1
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作者 Jackson J.Chakkoria Aditya Dubey +1 位作者 Arnan Mitchell Andreas Boes 《Opto-Electronic Advances》 2025年第2期46-79,共34页
Lithium niobate(LN)has remained at the forefront of academic research and industrial applications due to its rich material properties,which include second-order nonlinear optic,electro-optic,and piezoelectric properti... Lithium niobate(LN)has remained at the forefront of academic research and industrial applications due to its rich material properties,which include second-order nonlinear optic,electro-optic,and piezoelectric properties.A further aspect of LN’s versatility stems from the ability to engineer ferroelectric domains with micro and even nano-scale precision in LN,which provides an additional degree of freedom to design acoustic and optical devices with improved performance and is only possible in a handful of other materials.In this review paper,we provide an overview of the domain engineering techniques developed for LN,their principles,and the typical domain size and pattern uniformity they provide,which is important for devices that require high-resolution domain patterns with good reproducibility.It also highlights each technique's benefits,limitations,and adaptability for an application,along with possible improvements and future advancement prospects.Further,the review provides a brief overview of domain visualization methods,which is crucial to gain insights into domain quality/shape and explores the adaptability of the proposed domain engineering methodologies for the emerging thin-film lithium niobate on an insulator platform,which creates opportunities for developing the next generation of compact and scalable photonic integrated circuits and high frequency acoustic devices. 展开更多
关键词 lithium niobate FERROELECTRIC domain engineering lithium niobate on insulator domain visualization periodic poling quasi-phase matching acoustic
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Hierarchical detection and tracking for moving targets in underwater wireless sensor networks 被引量:1
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作者 Yudong Li Hongcheng Zhuang +2 位作者 Long Xu Shengquan Li Haibo Lu 《Digital Communications and Networks》 2025年第2期556-562,共7页
It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sens... It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sensor Networks(UWSNs).To this end,this paper investigates the relationship between the Degree of Target Change(DoTC)and the detection period,as well as the impact of individual nodes.A Hierarchical Detection and Tracking Approach(HDTA)is proposed.Firstly,the network detection period is determined according to DoTC,which reflects the variation of target motion.Secondly,during the network detection period,each detection node calculates its own node detection period based on the detection mutual information.Taking DoTC as pheromone,an ant colony algorithm is proposed to adaptively adjust the network detection period.The simulation results show that the proposed HDTA with the optimizations of network level and node level significantly improves the detection accuracy by 25%and the network energy consumption by 10%simultaneously,compared to the traditional adaptive period detection schemes. 展开更多
关键词 Underwater wireless sensor networks The degree of target change Mutual information PHEROMONE Adaptive period
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Insulin-induced severe thyrotoxic periodic paralysis:A case report
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作者 Yan-Li Wang Jian Li 《World Journal of Clinical Cases》 SCIE 2025年第7期46-51,共6页
BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue... BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of paralysis.This article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP patients.CASE SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening half-day.His medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week earlier.He was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade 1.Emergency department tests showed hypokalemia of 1.6 mmol/L.The paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g orally.Weakness in the arms and legs improved.He was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing TPP.We stopped his insulin and he was discharged with a potassium level of 4.0 mmol/L.CONCLUSION Insulin is a trigger for TPP and should be avoided in patients with hyperthyroidism.Early recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis. 展开更多
关键词 Thyrotoxic periodic paralysis Potassium metabolism disorders INSULIN Triggers of paralysis Case report
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Symmetric Periodic Solution of Linear Periodic Matrix Equations via BCR Algorithm
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作者 MA Changfeng XIE Yajun 《数学进展》 北大核心 2025年第4期881-890,共10页
Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently so... Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently solving linear systems Aα=b.The objective of this paper is to provide one new iterative algorithm based on BCR method to find the symmetric periodic solutions of linear periodic matrix equations.This kind of periodic matrix equations has not been dealt with yet.This iterative method is guaranteed to converge in a finite number of steps in the absence of round-off errors.Some numerical results are performed to illustrate the efficiency and feasibility of new method. 展开更多
关键词 periodic matrix equation biconjugate residual method symmetric periodic solution convergence analysis
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