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THE(p,q)-ANALOG OF MULTIVALENT BAZILEVIC FUNCTIONS ASSOCIATED WITH A LIMACON
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作者 HUANG An LONG Pin-hong +1 位作者 LIU Jin-lin Gangadharan Murugusundaramoorthy 《数学杂志》 2024年第6期471-484,共14页
This paper studies the problem of functional inequalities for analytic functions in classical geometric function theory.Using the di erential subordination principle and(p,q)-derivative operator,it introduces(p,q)-ana... This paper studies the problem of functional inequalities for analytic functions in classical geometric function theory.Using the di erential subordination principle and(p,q)-derivative operator,it introduces(p,q)-analog of a class of multivalently Bazilevic functions as-sociated with a limacon function,and obtains the corresponding coefficient estimates and the Fekete-Szego inequality,which extend and improve the related results for starlike functions,even q-starlike functions. 展开更多
关键词 Fekete-Szego inequality symmetric Toeplitz determinant multivalent function Bazilevic function (p q)-derivative operator
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A Cauchy integral formula for(p,q)-monogenic functions withα-weight
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作者 GAO Long DU Xiao-jing +1 位作者 LIU Yue XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期545-553,共9页
Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-... Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic functions withα-weight are given. 展开更多
关键词 (p q)-monogenic functions with-weight Cauchy-pompeiu formula Cauchy integral formula Cauchy integral theorem
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Functionalized selenium nanoparticles ameliorated acetaminophen-induced hepatotoxicity through synergistically triggering PKCδ/Nrf2 signaling pathway and inhibiting CYP 2E1
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作者 Si Zou Yetao Gong +4 位作者 Xiujie Li Yanbin Wu Jinzhong Wu Jianguo Wu Ka-Hing Wong 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期932-945,共14页
Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative stress.Functionalized SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic ac... Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative stress.Functionalized SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic activity and clinical application value.Herein,this work was conducted to investigate the protective effect of Pleurotus tuber-regium polysaccharide-protein complex funtionnalized SeNPs(PTR-SeNPs)against acetaminophen(APAP)-induced oxidative injure in HepG2 cells and C57BL/6J mouse liver.Further elucidation of the underlying molecular mechanism,in particular their modulation of Nrf2 signaling pathway was also performed.The results showed that PTR-SeNPs could significantly ameliorate APAP-induced oxidative injury as evidenced by a range of biochemical analysis,histopathological examination and immunoblotting study.PTR-SeNPs could hosphorylate and activate PKCδ,depress Keap1,and increase nuclear accumulation of Nrf2,resulting in upregulation of GCLC,GCLM,HO-1 and NQO-1 expression.Besides,PTR-SeNPs suppressed the biotransformation of APAP to generate intracellular ROS through CYP 2E1 inhibition,restoring the mitochondrial morphology.Furthermore,the protective effect of PTR-SeNPs against APAP induced hepatotoxicity was weakened as Nrf2 was depleted in vivo,indicating the pivotal role of Nrf2 signaling pathway in PTR-SeNPs mediated hepatoprotective efficacy.Being a potential hepatic protectant,PTR-SeNPs could serve as a new source of selenium supplement for health-promoting and biomedical applications. 展开更多
关键词 pTR-SeNps(polysaccharide-proteincomplex functionalized selenium nanoparticles) Acetaminophen-induced hepatotoxicity Nuclear factor erythroid 2-related factor 2 Cytochrome p450 enzyme 2E1 Mitochondria
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基于电磁时间反演P范数判据的配电网故障定位 被引量:1
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作者 刘青 黄玉河 +2 位作者 王宇 付瑶 王乐之 《电力系统保护与控制》 EI CSCD 北大核心 2024年第3期74-82,共9页
目前电磁时间反演(electromagnetic time reversal,EMTR)多应用在单一线路故障定位,且现有判据在高阻抗接地情况下效果不理想。针对上述问题,基于EMTR故障定位原理和均匀传输线理论推导了传播过程中线路故障信号与测量信号的传递函数,... 目前电磁时间反演(electromagnetic time reversal,EMTR)多应用在单一线路故障定位,且现有判据在高阻抗接地情况下效果不理想。针对上述问题,基于EMTR故障定位原理和均匀传输线理论推导了传播过程中线路故障信号与测量信号的传递函数,根据传递函数的相关性提出了P范数判据。利用ATP-EMTP搭建10 kV配电网线路,对比了2范数与P范数判据在复杂配电网中的定位性能,并验证了所提判据在混合配电网线路的适用性。最后,分析了配电网发生低阻抗及高阻抗接地故障下P范数判据的鲁棒性。仿真结果表明,该方法在过渡电阻高达3 kΩ的情况下能准确定位,且定位精度高,受噪声、故障类型和采样频率的影响小。 展开更多
关键词 电磁时间反演 传递函数 p范数 配电网 故障定位 高阻抗接地
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高压管汇材料疲劳性能测试及P-S-N模型曲线的拟合 被引量:1
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作者 黄艳娟 周思柱 李宁 《长江大学学报(自然科学版)》 2024年第3期55-61,共7页
高压管汇作为压裂设备中的主要易损件之一,其失效危害较大。它的失效原因主要是疲劳、冲蚀、腐蚀或者材料缺陷引起的刺漏和爆裂,其中尤以疲劳失效最不可预估。目前,对于高压管汇材料的疲劳性能研究不够深入,为解决高压管汇材料疲劳寿命... 高压管汇作为压裂设备中的主要易损件之一,其失效危害较大。它的失效原因主要是疲劳、冲蚀、腐蚀或者材料缺陷引起的刺漏和爆裂,其中尤以疲劳失效最不可预估。目前,对于高压管汇材料的疲劳性能研究不够深入,为解决高压管汇材料疲劳寿命的准确描述问题,以某国产高压管汇材料为例,进行了一系列疲劳试验,并基于试验数据,采用多种分布模型和不同S-N模型进行拟合分析,得出综合评价拟合能力最强的P-S-N模型。结果表明,该材料在中长疲劳寿命区,Weibull三参数模型在7级应力水平下综合评价能力最好;在存活率分别为50%、90%、99%、99.9%时,指数S-N模型的拟合系数均大于0.98,拟合能力最好。得出的P-S-N模型曲线可以为高压管汇的疲劳寿命以及安全设计提供依据。 展开更多
关键词 高压管汇材料 正态分布模型 Weibull分布模型 p-S-N模型 幂函数S-N模型 指数S-N模型
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P7C3-A20 treats traumatic brain injury in rats by inhibiting excessive autophagy and apoptosis 被引量:2
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作者 Zhiqing Yang Zhenchao Wang +4 位作者 Xiaoqi Deng Lingxin Zhu Zhaomeng Song Changyu Cao Xinran Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1078-1083,共6页
Traumatic brain injury is a severe health problem leading to autophagy and apoptosis in the brain.3,6-Dibromo-beta-fluoro-N-(3-methoxyphenyl)-9H-carbazole-9-propanamine(P7C3-A20)can be neuroprotective in various disea... Traumatic brain injury is a severe health problem leading to autophagy and apoptosis in the brain.3,6-Dibromo-beta-fluoro-N-(3-methoxyphenyl)-9H-carbazole-9-propanamine(P7C3-A20)can be neuroprotective in various diseases,including ischemic stroke and neurodegenerative diseases.However,whether P7C3-A20 has a therapeutic effect on traumatic brain injury and its possible molecular mechanisms are unclear.Therefore,in the present study,we investigated the therapeutic effects of P7C3-A20 on traumatic brain injury and explored the putative underlying molecular mechanisms.We established a traumatic brain injury rat model using a modified weight drop method.P7C3-A20 or vehicle was injected intraperitoneally after traumatic brain injury.Severe neurological deficits were found in rats after traumatic brain injury,with deterioration in balance,walking function,and learning memory.Furthermore,hematoxylin and eosin staining showed significant neuronal cell damage,while terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining indicated a high rate of apoptosis.The presence of autolysosomes was observed using transmission electron microscope.P7C3-A20 treatment reversed these pathological features.Western blotting showed that P7C3-A20 treatment reduced microtubule-associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ)autophagy protein,apoptosis-related proteins(namely,Bcl-2/adenovirus E1B 19-kDa-interacting protein 3[BNIP3],and Bcl-2 associated x protein[Bax]),and elevated ubiquitin-binding protein p62(p62)autophagy protein expression.Thus,P7C3-A20 can treat traumatic brain injury in rats by inhibiting excessive autophagy and apoptosis. 展开更多
关键词 ApOpTOSIS AUTOpHAGY CORTEX HIppOCAMpUS motor function p7C3-A20 traumatic brain injury
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Role of cytochrome P450 polymorphisms and functions in development of ulcerative colitis 被引量:5
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作者 Alaattin Sen Holger Stark 《World Journal of Gastroenterology》 SCIE CAS 2019年第23期2846-2862,共17页
Cytochromes P450 s(CYPs) are terminal enzymes in CYP dependent monooxygenases, which constitute a superfamily of enzymes catalysing the metabolism of both endogenous and exogenous substances. One of their main tasks i... Cytochromes P450 s(CYPs) are terminal enzymes in CYP dependent monooxygenases, which constitute a superfamily of enzymes catalysing the metabolism of both endogenous and exogenous substances. One of their main tasks is to facilitate the excretion of these substances and eliminate their toxicities in most phase 1 reactions. Endogenous substrates of CYPs include steroids, bile acids, eicosanoids, cholesterol, vitamin D and neurotransmitters. About 80% of currently used drugs and environmental chemicals comprise exogenous substrates for CYPs. Genetic polymorphisms of CYPs may affect the enzyme functions and have been reported to be associated with various diseases and adverse drug reactions among different populations. In this review, we discuss the role of some critical CYP isoforms(CYP1 A1, CYP2 D6, CYP2 J2, CYP2 R1,CYP3 A5, CYP3 A7, CYP4 F3, CYP24 A1, CYP26 B1 and CYP27 B1) in the pathogenesis or aetiology of ulcerative colitis concerning gene polymorphisms. In addition, their significance in metabolism concerning ulcerative colitis in patients is also discussed showing a clear underestimation in genetic studies performed so far. 展开更多
关键词 CYTOCHROME p450 polymorphism function ULCERATIVE COLITIS AETIOLOGY
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利用近震Sp转换波到时和远震接收函数P波峰值延迟研究华北盆地浅部结构
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作者 朱冰清 王伟涛 +5 位作者 谢俊举 李志伟 姚新强 黄翔 卞真付 林逸 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第6期2272-2290,共19页
收集2017—2020年中国地震科学探测台阵在华北地区布设观测宽频带流动地震观测台采集的高信噪比近震远震地震波形,采用远震接收函数P波峰值延迟和近震Sp转换波到时对华北沉积层厚度进行了估算.由远震接收函数P波峰值延迟,近震Sp转换波和... 收集2017—2020年中国地震科学探测台阵在华北地区布设观测宽频带流动地震观测台采集的高信噪比近震远震地震波形,采用远震接收函数P波峰值延迟和近震Sp转换波到时对华北沉积层厚度进行了估算.由远震接收函数P波峰值延迟,近震Sp转换波和S波到时差方法推断的华北地区沉积层厚度在6~7 km,燕山造山带区域沉积层厚度较小,结晶基底埋深一般小于1 km,华北盆地中部和东南部盆地结晶基底埋深较厚,厚度普遍大于3 km,局部厚度可达7 km.盆地内地垒式隆起区邢衡隆起有3 km厚度的沉积层,冀中坳陷、黄骅坳陷厚度6~7 km;沉积层厚度与地质构造相对应,坳陷区沉积层厚度较大,隆起区沉积层厚度较小,体现了沉积盆地内部不同二级块体的沉降差异.震相拾取误差、震源方位角和震中距对沉积厚度计算结果影响不明显;进行时深转换采用的一维速度模型准确性对计算结果存在一定影响.总体来说,远震接收函数P波峰值延迟和近震Sp转换波到时可以研究沉积层厚度,能够可靠、有效地确定沉积层厚度结构的特征,为地震风险评估提供基础信息. 展开更多
关键词 沉积层 近震Sp转换波到时 远震接收函数p波峰值延迟
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MiR-19a-3p regulates the Forkhead box F2-mediated Wnt/β-catenin signaling pathway and affects the biological functions of colorectal cancer cells 被引量:8
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作者 Fu-Bing Yu Juan Sheng +3 位作者 Jia-Man Yu Jing-Hua Liu Xiang-Xin Qin Bo Mou 《World Journal of Gastroenterology》 SCIE CAS 2020年第6期627-644,共18页
BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS... BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS Sixty-two CRC patients admitted to the hospital were enrolled into the study group,and sixty healthy people from the same period were assigned to the control group.Elbow venous blood was sampled from the patients and healthy individuals,and blood serum was saved for later analysis.MiR-19a-3p mimics,miR-19a-3p inhibitor,miR-negative control,small interfering-FOXF2,and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells.Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells,and western blot(WB)analysis was conducted to evaluate the levels of FOXF2,glycogen synthase kinase 3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),β-catenin,p-β-catenin,α-catenin,Ncadherin,E-cadherin,and vimentin.The MTT,Transwell,and wound healing assays were applied to analyze cell proliferation,invasion,and migration,respectively,and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2.RESULTS The patients showed high serum levels of miR-19a-3p and low levels of FOXF2,and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8.MiR-19a-3p and FOXF2 were related to sex,tumor size,age,tumor-nodemetastasis staging,lymph node metastasis,and differentiation of CRC patients.Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelialmesenchymal transition,invasion,migration,and proliferation of cells.WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β,β-catenin,N-cadherin,and vimentin;and increased the levels of GSK-3β,p-β-catenin,α-catenin,and Ecadherin.The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2.In addition,a rescue experiment revealed that there were no differences in cell proliferation,invasion,and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group.CONCLUSION Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway,thereby affecting the epithelial-mesenchymal transition,proliferation,invasion,and migration of cells.Thus,miR-19a-3p is likely to be a therapeutic target in CRC. 展开更多
关键词 MiR-19a-3p Forkhead box F2 Wnt/β-catenin signaling pathway Biological function Colorectal cancer Western blot
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Sufficient Optimality Conditions for Multiobjective Programming Involving (V, ρ)h,ψ-type Ⅰ Functions 被引量:3
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作者 ZHANG Qing-xiang JIANG Yan KANG Rui-rui 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期409-416,共8页
New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebr... New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebraic operation. The examples of (V, ρ)_(h,φ)-type I functions are given. The sufficient optimality conditions are obtained for multi-objective programming problem involving above new generalized convexity. 展开更多
关键词 multiobjective programming (V p)h φ-type I functions pareto efficient solu-tion sufficient optimality conditions
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分数阶p-Laplace方程解的单调性公式
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作者 王琦 沃维丰 《宁波大学学报(理工版)》 2024年第1期38-42,共5页
研究了分数阶p-Laplace方程解的单调性公式.基于Caffarelli-Silverstre的延拓技术,将分数阶p-Laplace方程相应的扩展问题表述为半空间中一个退化或奇异局部方程.通过建立与扩展问题相关的Almgren型频率函数,结合散度定理和积分估计获得... 研究了分数阶p-Laplace方程解的单调性公式.基于Caffarelli-Silverstre的延拓技术,将分数阶p-Laplace方程相应的扩展问题表述为半空间中一个退化或奇异局部方程.通过建立与扩展问题相关的Almgren型频率函数,结合散度定理和积分估计获得了延拓函数的单调性公式. 展开更多
关键词 分数阶p-Laplace方程 延拓技术 频率函数 单调性
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血清p-tau181与帕金森病的相关性
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作者 田章林 龙波 +1 位作者 董语涵 魏有东 《中国实用神经疾病杂志》 2024年第2期139-143,共5页
目的探究帕金森病(PD)患者血清磷酸化tau181(p-tau181)浓度及其与疾病严重程度、认知损害、患者功能预后的相关性。方法纳入2021-07—2022-02于重庆医科大学附属第一医院神经内科住院或门诊就诊的PD患者40例和同期健康对照(HC)35例为研... 目的探究帕金森病(PD)患者血清磷酸化tau181(p-tau181)浓度及其与疾病严重程度、认知损害、患者功能预后的相关性。方法纳入2021-07—2022-02于重庆医科大学附属第一医院神经内科住院或门诊就诊的PD患者40例和同期健康对照(HC)35例为研究对象。采用酶联免疫吸附试验(ELISA)检测血清p-tau181水平。入院或就诊时评估帕金森病统一评分量表(UPDRS)和Hoehn-Yahr(H-Y)分期量表,以评估PD患者的疾病严重程度。认知功能由蒙特利尔认知评估(MoCA)量表测评。6个月后随访患者UPDRS评分及H-Y分期,进一步评估血清p-tau181与患者预后的相关性。结果与HC相比,PD患者血清p-tau181水平升高,但差异无统计学意义[1.01(0.28~2.63)ng/L比0.53(0.04~3.72)ng/L,P=0.55]。PD早期和晚期患者p-tau181水平差异无统计学意义(P=0.80),认知损害PD患者、认知正常PD患者与HC者p-tau181水平差异无统计学意义(P=0.63)。p-tau181与病程(r=-0.14,P=0.37)、UPDRS评分(r=0.02,P=0.89)、MoCA评分(r=0.16,P=0.32)均无相关性。预后良好组与预后不佳组血清p-tau181水平表达无统计学差异(P=0.74)。结论p-tau181在帕金森病患者血清表达增加,与疾病严重程度、认知损害、功能预后无明确相关性。 展开更多
关键词 帕金森病 磷酸化tau蛋白181 认知损害 疾病严重程度 功能预后
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Constructive Approximation by Superposition of Sigmoidal Functions 被引量:2
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作者 Danilo Costarelli Renato Spigler 《Analysis in Theory and Applications》 2013年第2期169-196,共28页
In this paper, a constructive theory is developed for approximating func- tions of one or more variables by superposition of sigmoidal functions. This is done in the uniform norm as well as in the L^p norm. Results fo... In this paper, a constructive theory is developed for approximating func- tions of one or more variables by superposition of sigmoidal functions. This is done in the uniform norm as well as in the L^p norm. Results for the simultaneous approx- imation, with the same order of accuracy, of a function and its derivatives (whenever these exist), are obtained. The relation with neural networks and radial basis func- tions approximations is discussed. Numerical examples are given for the purpose of illustration. 展开更多
关键词 Sigmoidal functions multivariate approximation L^p approximation neural net-works radial basis functions.
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AREA INTEGRAL FUNCTIONS FOR SECTORIAL OPERATORS ON L^p SPACES 被引量:1
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作者 陈泽乾 孙牧 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期739-747,共9页
Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the re... Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the results of Cowling, Doust, McIntosh, Yagi, and Le Merdy on H^∞ functional calculus of seetorial operators on LP-spaces hold true when the square functions are replaced by the area integral functions. 展开更多
关键词 Sectorial operator H^∞ functional calculus area integral function square function L^p space
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Effective transmittance of Fabry–Perot cavity under non-parallel beam incidence
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作者 吕寅生 谢品华 +2 位作者 徐晋 李友涛 张华荣 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期449-457,共9页
The Fabry–Perot(FP) resonant cavity is widely used in laser and spectroscopic measurements due to its unique interference transfer function(ITF). In the ideal case of parallel incident light, the ITF of the FP resona... The Fabry–Perot(FP) resonant cavity is widely used in laser and spectroscopic measurements due to its unique interference transfer function(ITF). In the ideal case of parallel incident light, the ITF of the FP resonant cavity can be expressed by the Airy function. However, in reality, it is difficult to achieve perfect parallelism with collimated beams. In this article, a theoretical model is established for non-parallel light incidence, which assumes that the non-parallel incident light is a cone-shaped beam, and the cone angle is used to quantify the non-parallelism of the beam. The transmittance function of the FP resonant cavity under non-parallel light incidence is derived. The accuracy of the model is experimentally verified. Based on this model, the effects of divergence angle, tilt angle and FP cavity parameters(reflectivity, cavity length)on the ITF are studied. The reasons for the decrease in peak value, broadening and asymmetry of the interference peak under non-parallel light incidence are explained. It is suggested that a fine balance between the interference peak and the collimation effect of the incident light should be considered in the design and application of FP resonant cavities, especially for tilted applications such as angle-scanned spectroscopy. The research results of this article have certain significance for the design and application of FP resonant cavities. 展开更多
关键词 Fabry–pérot(Fp)resonant cavity interference transfer function Airy function non-parallel beam incidence
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Mo_(2)P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study
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作者 Dongxu Jiao Zhongxu Wang +4 位作者 Yuejie Liu Qinghai Cai Jingxiang Zhao Carlos R.Cabrera Zhongfang Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期207-214,共8页
Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the devel... Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2)and CO_(2)molecules remains rather challenging.Herein,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea production.Our results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic properties.Interestingly,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 eV)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side reactions.The outstanding catalytic activity of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active sites.Our findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis. 展开更多
关键词 C-N coupling density functional theory Mo_(2)p monolayer urea synthesis
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W ^(1,p)(R^n)-BOUNDEDNESS FOR MAXIMAL FUNCTIONS
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作者 Li Cheng Department of Mathematics Lishui University Lishui, 323000P. R. China 《Analysis in Theory and Applications》 2009年第1期86-91,共6页
In this paper, we get W 1,p(Rn)-boundedness for tangential maximal func- tion and nontangential maximal function , which improves J.Kinnunen, P.Lindqvist and Tananka’s results.
关键词 tangential maximal function nontangential maximal function W 1 p(Rn)- boundedness
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Dominating functions with integer values in graphs a survey 被引量:2
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作者 康丽英 单而芳 《Journal of Shanghai University(English Edition)》 CAS 2007年第5期437-448,共12页
For an arbitrary subset P of the reals, a function f : V →P is defined to be a P-dominating function of a graph G = (V, E) if the sum of its function values over any closed neighbourhood is at least 1. That is, fo... For an arbitrary subset P of the reals, a function f : V →P is defined to be a P-dominating function of a graph G = (V, E) if the sum of its function values over any closed neighbourhood is at least 1. That is, for every v ∈ V, f(N[v]) ≥ 1. The definition of total P-dominating function is obtained by simply changing ‘closed' neighborhood N[v] in the definition of P-dominating function to ‘open' neighborhood N(v). The (total) P-domination number of a graph G is defined to be the infimum of weight w(f) = ∑v ∈ V f(v) taken over all (total) P-dominating function f. Similarly, the P-edge and P-star dominating functions can be defined. In this paper we survey some recent progress on the topic of dominating functions in graph theory. Especially, we are interested in P-, P-edge and P-star dominating functions of graphs with integer values. 展开更多
关键词 p-dominating function signed domination signed total domination minus domination minus total domination.
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Convexity for New Integral Operator on k-uniformly p-valent a-convex Functions of Complex Order 被引量:1
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作者 LI Shu-hai MA Li-na A O-en 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期88-96,共9页
In this paper, we obtain the convexity of new general integral operator on some classes of k-uniformly p-valent a-convex functions of complex order. These results extend some known theorems.
关键词 analytic functions p-valently k-uniformly STARLIKE CONVEX integral operator
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慢性非缺血性心力衰竭患者血小板PAC-1和CD62p的表达及其与心功能的关系
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作者 马丽娜 曹振华 杨冰 《海南医学》 CAS 2024年第9期1298-1302,共5页
目的探讨慢性非缺血性心力衰竭患者血小板膜糖蛋白纤维蛋白原受体(PAC-1)和P选择素(CD62p)的表达及其与心功能的关系。方法选取2019年1月至2022年1月天津市南开医院收治的185例慢性非缺血性心力衰竭患者作为观察组,根据纽约心脏病学会(N... 目的探讨慢性非缺血性心力衰竭患者血小板膜糖蛋白纤维蛋白原受体(PAC-1)和P选择素(CD62p)的表达及其与心功能的关系。方法选取2019年1月至2022年1月天津市南开医院收治的185例慢性非缺血性心力衰竭患者作为观察组,根据纽约心脏病学会(NYHA)心功能分级将观察组患者分为心功能Ⅱ级组58例、心功能Ⅲ级组88例和心功能Ⅳ级组39例,根据左室射血分数(LVEF)将观察组患者分为射血分数保留心衰组(HFpEF)123例、射血分数临界值心衰组(HFmrEF)25例和射血分数下降心衰组(HFrEF)37例,再以B型钠尿肽(BNP)中位数为界将观察组患者分为高BNP组109例和低BNP组76例;另选取同期心功能正常的就诊者55例作为对照组。比较各组患者的基本临床信息、生化、BNP指标和PAC-1、CD62p的表达水平,采用Pearson相关分析法分析PAC-1、CD62p水平与BNP、LVEF的关系。结果观察组患者的PAC-1、CD62p水平分别为(23.67±16.54)%、(10.43±9.19)%,明显高于对照组的(9.33±9.63)%、(4.24±5.49)%,差异均有统计学意义(P<0.05);不同心功能分级患者对比发现,PAC-1、BNP水平为Ⅳ级>Ⅲ级>Ⅱ级>对照组,CD62p水平为Ⅳ级>Ⅲ级、Ⅱ级>对照组,差异均有统计学意义(P<0.05);不同LVEF分级患者对比发现,PAC-1水平为HFrEF组>HFmrEF组、HFpEF组>对照组,BNP水平为HFrEF组>HFmrEF组>HFpEF组>对照组,HFpEF组、HFmrEF组、HFrEF组CD62p水平分别为(10.72±9.17)%、(9.87±11.19)%、(9.84±7.88)%,明显高于对照组的(4.24±5.49)%,差异均有统计学意义(P<0.05);高BNP组患者的PAC-1、CD62p分别为(26.97±16.94)%、(11.05±9.62)%,明显高于低BNP组的(13.80±12.82)%、(6.97±7.54)%,差异均有统计学意义(P<0.05);经Pearson相关分析结果显示,PAC-1、CD62p与BNP呈正相关(r=0.363、0.182,P<0.05),PAC-1与LVEF呈负相关(r=-0.297,P<0.05)。结论慢性非缺血性心力衰竭患者的PAC-1、CD62p水平均明显增高,且与心功能有关,检测其水平有助于为患者的病情评估及临床治疗提供参考依据。 展开更多
关键词 非缺血性心衰 慢性心力衰竭 血小板膜糖蛋白纤维蛋白原受体 p选择素 心功能
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