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Generalized spline adaptive filtering algorithm based on q-hyperbolic function
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作者 Shiwei Yun Sihai Guan +1 位作者 Chuanwu Zhang Bharat Biswal 《Journal of Automation and Intelligence》 2025年第2期125-135,共11页
Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic fu... Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic function-like objective functions.Specifically,a series of generalized new SAF algorithms are proposed by introducing the q-deformed hyperbolic function as the cost function,named SAF-qDHSI,SAF-qDHCO,SAFqDHTA&SAF-qDHSE algorithms,respectively.Then,the proposed algorithm is theoretically demonstrated with detailed mean convergence and computational complexity analysis;secondly,the effect of different q values on the performance of the new algorithm is verified through data simulation;the new algorithm still has better performance under the interference of Gaussian noise and non-Gaussian noise even when facing the system mutation;finally,the new algorithm is verified through the measured engineering data,and the results show that the new algorithm has better convergence and robustness compared with the existing algorithm.In conclusion,the generalized algorithm based on the new cost function proposed in this paper is more effective in nonlinear system identification. 展开更多
关键词 Nonlinear systems spline adaptive filtering q-deformed hyperbolic functions
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Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury 被引量:1
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作者 Ziwei Fan Mengxian Jia +16 位作者 Jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian Jiashu Lian Xin Hua Jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu Zhu Ying Wang Zhihui Huang Honglin Teng 《Neural Regeneration Research》 SCIE CAS 2025年第11期3287-3301,共15页
The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia ... The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be crucial.Tryptanthrin possesses an anti-inflammatory biological function.However,its roles and the underlying molecular mechanisms in spinal cord injury remain unknown.In this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in vitro.Tryptanthrin promoted M2 polarization through inactivating the cGAS/STING/NF-κB pathway.Additionally,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord injury.Finally,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal apoptosis.Taken together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype. 展开更多
关键词 cGAS/STING functional recovery MICROGLIA neuroinflammation neuroprotection nuclear factor-κb POLARIZATION spinal cord injury TRYPTANTHRIN
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Applying the Radial Basis Function Method to Estimate the Distribution of Total Suspended Matter Concentration in Hangzhou Bay
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作者 CHEN Wanqian GAO Jinpeng +5 位作者 XU Minjie LIU Zezheng LI Bingtian LV Jing LI Shujiang SUN Junchuan 《Journal of Ocean University of China》 2025年第3期557-568,共12页
Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of thes... Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data. 展开更多
关键词 ocean remote sensing satellite total suspended matter concentration INTERPOLATION radial basis function Kriging method basic spline method
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Clinical,genetic and functional perspectives on ATP-binding cassette subfamily B member 4 variants in five cholestasis adults
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作者 Yu-Hang Weng Yu-Feng Zheng +5 位作者 Dan-Dan Yin Qing-Fang Xiong Jin-Long Li Shun-Xin Li Wei Chen Yong-Feng Yang 《World Journal of Gastroenterology》 2025年第14期142-156,共15页
BACKGROUND ATP-binding cassette subfamily B member 4(ABCB4)deficiency is associated with cholestatic liver disease primarily because of missense mutations,and many variants remain unidentified.Here,we validate the pat... BACKGROUND ATP-binding cassette subfamily B member 4(ABCB4)deficiency is associated with cholestatic liver disease primarily because of missense mutations,and many variants remain unidentified.Here,we validate the pathogenicity and mechanism of ABCB4 variants in clinical and in vitro trials,hypothesizing that these variants are responsible for impaired biliary function and contribute to the development of cholestatic liver diseases.AIM To clarify the functional features and pathogenicity of ABCB4 variants.METHODS Clinical data were collected from five patients with cholestatic liver disease that was initially not detected by routine examinations.Later,whole-exome sequencing confirmed ABCB4 variants and the patients were treated from January 2017 to December 2023.Pathogenic mechanisms were analyzed using bioinformatics tools,and a cell model in vitro was established to investigate ABCB4 mRNA expression,multidrug resistance protein 3(MDR3)expression,cellular localization,and phosphatidylcholine secretion.Results were compared using Student's t-tests.RESULTS Five missense variants(c.1757T>A,c.1865G>A,c.2362C>T,c.2777C>T and c.3250C>T),one intron variant(c.537-32G>T),and one synonymous(c.C504T)variant were identified.Three of the five patients had various degrees of cholestasis,two presented with liver cirrhosis,and all had elevated gamma-glutamyl transferase.Three of the four patients who underwent a liver biopsy had bile duct dilation,and one had gallstones.Two of the four patients had normal and reduced MDR3 immunohistochemical levels.Bioinformatic analysis indicated that these variants were likely pathogenic except c.C504T variant.None of the missense variants influenced subcellular MDR3 Localization in vitro.However,the c.1865G>A variant significantly decreased ABCB4 mRNA values,and all missense variants down-regulated phosphatidylcholine secretion.CONCLUSION This study uncovered new ABCB4 variants and emphasized the pathogenic potential of specific variants.The findings from five patients provided insight into the pathogenic mechanisms underlying ABCB4-related diseases. 展开更多
关键词 ATP-binding cassette subfamily b member 4 Multidrug resistance protein 3 CHOLESTASIS functional analysis CLINICAL Gene mutation Whole-exome sequencing
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Rate of abnormal renal function index and related risk factors in patients with chronic hepatitis B
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作者 Guo-Feng Gao Xiao-Yu Wang Jiao Yu 《World Journal of Gastroenterology》 2025年第25期16-25,共10页
BACKGROUND Patients with chronic hepatitis B(CHB)require long-term antiviral therapy.The effects of different antiviral drugs on kidney function are unclear.There is a lack of effective markers for monitoring early re... BACKGROUND Patients with chronic hepatitis B(CHB)require long-term antiviral therapy.The effects of different antiviral drugs on kidney function are unclear.There is a lack of effective markers for monitoring early renal impairment.AIM To investigate the rate of abnormal renal function index and related potential hazards in patients with CHB.METHODS Clinical data of patients with CHB with urinaryβ2-microglobulin(β2-M)detec-tion,including demographic characteristics,hepatitis B virus(HBV)DNA,serum liver function(alanine aminotransferase,aspartate aminotransferase,total bilirubin,direct bilirubin),serum renal function(urea nitrogen,creatinine),blood lipid index(high density lipoprotein,low density lipoprotein,cholesterol,trigly-ceride),liver imaging,and other routine tests were retrospectively collected.The normal level of urinaryβ2-M and estimated glomerular filtration rate(eGFR)is defined as<0.173 mg/L and≥90 mL/min/1.73 m^(2),retrospectively.The pro-portion of patients with abnormal renal function index and related risk factors were analyzed.RESULTS A total of 500 patients with CHB were enrolled;these patients were aged 44.7±10.8 years,67.2%(336/500)were male,57.2%(286/500)were treated with anti-viral drugs,and 52.2%(261/500)had an HBV-related family history.In total,28.8%(144/500)of patients had fatty liver,35.0%(175/500)had liver fibrosis,and 13.2%(66/500)had cirrhosis.The proportion of patients with eGFR<90 mL/min/1.73 m^(2) was 43.2%(216/500),and the abnormal rate of urinaryβ2-M was 56.2%(281/500).There was no significant difference in the abnormal rate of urinaryβ2-M between the untreated group and the antiviral treated group(54.2%vs 57.7%;P=0.25).The abnormal rate ofβ2-M after long-term entecavir treatment(more than 1 year)was 54.6%(89/163).In the treatment group,56.4%(92/163)of patients with eGFR≥90 mL/min/1.73 m^(2) had abnormal urinaryβ2-M.CONCLUSION In patients with CHB,a higher proportion had greater urinaryβ2-M levels than eGFR for renal injury.Male patients should pay more attention to renal function and use antiviral regimens with a renal safety profile. 展开更多
关键词 Chronic hepatitis b Nucleos(t)ide analogues Renal function β2 microglobulin Glomerular filtration rate
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Dietary Zn proteinate with moderate chelation strength alleviates heat stress‑induced intestinal barrier function damage by promoting expression of tight junction proteins via the A20/NF‑κB p65/MMP‑2 pathway in the jejunum of broilers
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作者 Yangyang Hu Weiyun Zhang +12 位作者 Ke Yang Xi Lin Hsiao‑Ching Liu Jack Odle Miles Todd See Xiaoyan Cui Tingting Li Shengchen Wang Xiudong Liao Liyang Zhang Sufen Li Yun Hu Xugang Luo 《Journal of Animal Science and Biotechnology》 2025年第1期316-330,共15页
Background The aim of this study was to determine whether and how Zn proteinate with moderate chelation strength(Zn-Prot M)can alleviate heat stress(HS)-induced intestinal barrier function damage of broilers.A complet... Background The aim of this study was to determine whether and how Zn proteinate with moderate chelation strength(Zn-Prot M)can alleviate heat stress(HS)-induced intestinal barrier function damage of broilers.A completely randomized design was used for comparatively testing the effects of Zn proteinate on HS and non-HS broilers.Under high temperature(HT),a 1(Control,HT-CON)+2(Zn source)×2(added Zn level)factorial arrangement of treatments was used.The 2 added Zn sources were Zn-Prot M and Zn sulfate(ZnS),and the 2 added Zn levels were 30 and 60 mg/kg.Under normal temperature(NT),a CON group(NT-CON)and pair-fed group(NT-PF)were included.Results The results showed that HS significantly reduced mRNA and protein expression levels of claudin-1,occludin,junctional adhesion molecule-A(JAMA),zonula occludens-1(ZO-1)and zinc finger protein A20(A20)in the jejunum,and HS also remarkably increased serum fluorescein isothiocyanate dextran(FITC-D),endotoxin and interleukin(IL)-1βcontents,serum diamine oxidase(DAO)and matrix metalloproteinase(MMP)-2 activities,nuclear factor kappa-B(NF-κB)p65 mRNA expression level,and protein expression levels of NF-κB p65 and MMP-2 in the jejunum.However,dietary supplementation with Zn,especially organic Zn as Zn-Prot M at 60 mg/kg,significantly decreased serum FITC-D,endotoxin and IL-1βcontents,serum DAO and MMP-2 activities,NF-κB p65 mRNA expression level,and protein expression levels of NF-κB p65 and MMP-2 in the jejunum of HS broilers,and notably promoted mRNA and protein expression levels of claudin-1,ZO-1 and A20.Conclusions Our results suggest that dietary Zn,especially 60 mg Zn/kg as Zn-Prot M,can alleviate HS-induced intestinal barrier function damage by promoting the expression of TJ proteins possibly via induction of A20-mediated suppression of the NF-κB p65/MMP-2 pathway in the jejunum of HS broilers. 展开更多
关键词 A20/NF-κb p65/MMP-2 pathway bROILER Heat stress Intestinal barrier function Tight junction proteins Zn
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基于B-spline曲线的通风机多维度协同优化
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作者 蒋山杰 高全杰 +2 位作者 郭时敏 孙志波 曾锦荣 《暖通空调》 2025年第9期57-63,27,共8页
通风机在暖通空调系统中发挥着关键作用,主要用于送风、补风和通风。目前对建筑用通风机的研究仍存在模型复杂、计算困难的问题。本文提出利用多维度协同优化设计方法来优化通风机的气动性能。在优化设计过程中,采用B-spline曲线参数化... 通风机在暖通空调系统中发挥着关键作用,主要用于送风、补风和通风。目前对建筑用通风机的研究仍存在模型复杂、计算困难的问题。本文提出利用多维度协同优化设计方法来优化通风机的气动性能。在优化设计过程中,采用B-spline曲线参数化叶片表面形状,通过流场降维处理,在搭建的自动化平台上进行多目标优化进而筛选高效细化区间,继而在该区间内实施最优拉丁超立方抽样。基于样本的计算流体力学模拟结果表明,最优解的通风机压力和叶轮力矩分别为742.44 Pa和174.12 N,与原始方案相比,在保持通风机压力变化不大的同时叶轮力矩降低了16.33%,通风机效率提升了19.60%。该方法显著降低了方案寻优的成本,为通风机的性能评估提供了便利。 展开更多
关键词 b-spline曲线 离心通风机 多维度协同优化 NSGA-Ⅱ 气动性能 叶轮
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B-Spline曲线聚风装置直线翼垂直轴风力机启动性能数值模拟 被引量:2
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作者 李岩 马云飞 +2 位作者 佟国强 杨胜兵 肖振军 《排灌机械工程学报》 CSCD 北大核心 2024年第3期265-272,共8页
为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进... 为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进行设计:聚风装置与风轮间隙距离ΔL、底圆半径R_(1)、顶圆半径R_(2)、入口角度α_(1)和出口角度α_(2).设计方法采用二次旋转正交组合筛选最优模型,通过三维数值模拟研究聚风装置参数对直线翼垂直轴风力机启动性能的影响,获得了最佳外形参数组合.此外,对有无加装聚风装置的直线翼垂直轴风力机进行了静态三维数值模拟.结果表明,通过添加具有外凸流线型轮廓的聚风装置,直线翼垂直轴风力机的启动性能有显著提升.在风速较低的情况下,性能改善更加明显.聚风装置可使直线翼垂直轴风力机的平均启动力矩系数最大增加38.8%,峰值平均启动力矩系数最大可增加31.2%. 展开更多
关键词 垂直轴风力机 聚风装置 b-spline曲线 启动性能 数值模拟
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改进粒子群算法的无人机B样条曲线路径规划
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作者 杨火根 王艳 骆伟 《郑州大学学报(工学版)》 北大核心 2025年第4期8-15,共8页
针对粒子群算法在无人机路径规划中易陷入局部最优解,且在离散路径点光滑处理后对避障考虑不足的问题,提出一种基于改进粒子群算法的无人机三维B样条曲线路径规划方法。首先,综合考虑无人机路径长度、安全避障、飞行高度及平稳性等飞行... 针对粒子群算法在无人机路径规划中易陷入局部最优解,且在离散路径点光滑处理后对避障考虑不足的问题,提出一种基于改进粒子群算法的无人机三维B样条曲线路径规划方法。首先,综合考虑无人机路径长度、安全避障、飞行高度及平稳性等飞行性能要求,利用B样条曲线的几何性质构建路径规划模型;其次,采用改进的粒子群算法对模型进行求解,算法改进主要通过优化粒子初始化策略、惯性权重因子和学习因子更新策略、增加粒子扰动策略来实现;最后,在CEC2017标准测试函数集上进行测试。结果表明:改进的粒子群算法在对比算法中表现出更强的寻优能力,稳定性也更好。两个场景的仿真结果表明:所规划的路径代价可减少2%,稳定性可提高65%,路径安全避障且C 2连续,能满足无人机飞行综合性能要求。 展开更多
关键词 无人机 b样条曲线 路径规划 避障 改进粒子群算法
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改进B样条逼近时变滤波在电机轴承故障诊断中的应用
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作者 杨娜 刘晔 +1 位作者 徐元博 刘静超 《噪声与振动控制》 北大核心 2025年第3期151-157,共7页
对电机轴承进行有效的故障诊断,不仅可以保证设备平稳高效运行,而且可以及时发现和排除运行故障,防止事故的发生。然而,从故障轴承中提取出的振动信号属于时变非平稳信号。此外,强烈的环境噪声也会掩盖微弱的故障循环脉冲。针对上述问题... 对电机轴承进行有效的故障诊断,不仅可以保证设备平稳高效运行,而且可以及时发现和排除运行故障,防止事故的发生。然而,从故障轴承中提取出的振动信号属于时变非平稳信号。此外,强烈的环境噪声也会掩盖微弱的故障循环脉冲。针对上述问题,提出一种改进B样条逼近时变滤波方法用以处理轴承故障信号。该方法采用新颖的瞬时幅值和瞬时频率估计方法代替传统的希尔伯特变换方法,增强B样条逼近的精度从而提高滤波性能。首先,通过所提方法对轴承故障信号进行滤波处理突出故障信息;然后对滤波信号进行包络分析得到包络谱,从而得到故障特征频率。仿真和真实故障信号实验表明,采用该方法可以有效提取电机轴承故障微弱特征。因此,该方法可为电机轴承故障诊断提供一种新的技术。 展开更多
关键词 故障诊断 电机轴承 瞬时幅值 瞬时频率 改进b样条时变滤波
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HCMV感染对HBeAg阴性乙肝病毒感染孕妇病毒激活及血清免疫功能指标的影响
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作者 陈刚 许婷婷 余阿娜 《中华医院感染学杂志》 北大核心 2025年第1期86-90,共5页
目的观察人巨细胞病毒(HCMV)感染对乙型肝炎E抗原(HBeAg)阴性乙肝病毒(HBV)感染孕妇的HBV激活及血清免疫功能指标水平的影响。方法回顾性选取2019年1月-2023年10月黄山市人民医院收治的伴HCMV感染HBeAg阴性HBV感染孕妇85例为研究组,另... 目的观察人巨细胞病毒(HCMV)感染对乙型肝炎E抗原(HBeAg)阴性乙肝病毒(HBV)感染孕妇的HBV激活及血清免疫功能指标水平的影响。方法回顾性选取2019年1月-2023年10月黄山市人民医院收治的伴HCMV感染HBeAg阴性HBV感染孕妇85例为研究组,另选取同期无HCMV感染的HBeAg阴性HBV感染孕妇62例为对照组,入院时和分娩前采集静脉血,检测孕妇HBV-DNA拷贝数;检测两组产妇入院时及分娩前抗核抗体(ANA)、免疫相关因子[C-反应蛋白(CRP)、白细胞介素-6(IL-6)、免疫球蛋白G(IgG)、免疫球蛋白A(IgA)、免疫球蛋白M(IgM)]、血清肝功能标志物[(谷丙转氨酶(ALT)、谷草转氨酶(AST)]含量,并对母婴结局进行分析。结果孕妇分娩前,研究组HBV-DNA载量(3.82±0.90)log IU/ml显著高于对照组(3.24±0.35)log IU/ml(t=4.729,P<0.001),ANA阳性率32.94%高于对照组17.74%(P<0.05),CRP、IL-6、IgG、IgA、IgM水平分别为(32.74±3.38)mg/L、(22.07±2.35)ng/L、(15.14±1.63)mg/L、(4.28±0.45)mg/L、(1.85±0.21)mg/L,均高于对照组(P<0.05),ALT、AST分别为(49.95±15.27)U/L、(36.41±9.42)U/L,均高于对照组(P<0.05);两组母婴结局比较差异无统计学意义。结论HCMV感染可造成HBeAg阴性乙肝病毒感染孕妇HBV-DNA载量、ANA阳性率增加,引起免疫功能紊乱,增加病毒激活风险,但对母婴临床结局未见明显影响。 展开更多
关键词 人巨细胞病毒 乙型肝炎病毒 孕妇 病毒激活 免疫功能
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求解四阶半线性抛物方程的B样条有限元法
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作者 秦丹丹 李阳晴 黄文竹 《吉林大学学报(理学版)》 北大核心 2025年第5期1337-1347,共11页
首先,用三次B样条有限元法求解一类带有变系数的四阶半线性抛物方程,证明半离散格式的稳定性和收敛性;其次,用Crank-Nicolson方法离散时间变量得到全离散格式,讨论全离散格式的稳定性和收敛性;最后,在数值算例中,采用Picard迭代方法处... 首先,用三次B样条有限元法求解一类带有变系数的四阶半线性抛物方程,证明半离散格式的稳定性和收敛性;其次,用Crank-Nicolson方法离散时间变量得到全离散格式,讨论全离散格式的稳定性和收敛性;最后,在数值算例中,采用Picard迭代方法处理非线性项,得到有限元法按照L 2模和H 2模的收敛阶. 展开更多
关键词 四阶半线性抛物方程 变系数 三次b样条有限元法 稳定性 收敛性
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氨基功能化MIL-53(Fe)对罗丹明B的吸附性能及机制研究
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作者 马锋锋 焦雅仙 +4 位作者 李庆 康宏兵 赵浩 张建 付嘉怡 《环境科学学报》 北大核心 2025年第7期243-257,共15页
通过一步溶剂法制备了含有氨基取代基的MIL-53(Fe)(NH_(2)-MIL-53(Fe)),并用于去除水溶液中的罗丹明B(RhB).利用SEM、XRD、XPS、FTIR等技术对MIL-53(Fe)和NH_(2)-MIL-53(Fe)的形貌和结构进行了表征.采用批量吸附实验研究了MIL-53(Fe)和N... 通过一步溶剂法制备了含有氨基取代基的MIL-53(Fe)(NH_(2)-MIL-53(Fe)),并用于去除水溶液中的罗丹明B(RhB).利用SEM、XRD、XPS、FTIR等技术对MIL-53(Fe)和NH_(2)-MIL-53(Fe)的形貌和结构进行了表征.采用批量吸附实验研究了MIL-53(Fe)和NH_(2)-MIL-53(Fe)对RhB的吸附特性,考察了溶液pH值、共存离子、投加量等因素的影响,研究了NH_(2)-MIL-53(Fe)的再生性能,并通过实验和表征结果探讨了吸附机制.结果表明,NH_(2)-MIL-53(Fe)和MIL-53(Fe)对RhB吸附的控速步骤为化学吸附,吸附过程分为液膜扩散、颗粒内扩散和吸附平衡3个阶段.等温吸附实验表明,NH_(2)-MIL-53(Fe)和MIL-53(Fe)对RhB的吸附行为可被Langmuir和Temkin模型很好地描述,拟合所得最大吸附量分别为796.5 mg·g^(-1)和549.1 mg·g^(-1),NH_(2)-MIL-53(Fe)对RhB的吸附性能比MIL-53(Fe)提高了45%.当溶液pH值在5~8时,MIL-53(Fe)和NH_(2)-MIL-53(Fe)对RhB的吸附效果最佳;经过5次吸附-再生试验,NH_(2)-MIL-53(Fe)对RhB的吸附容量仍能保持初始吸附量的85%.NH_(2)-MIL-53(Fe)吸附RhB的机制包括氢键作用(普通氢键和电荷辅助氢键)、路易斯酸碱作用、静电引力、π-π相互作用和π-π相互作用.NH_(2)-MIL-53(Fe)作为一种吸附剂,在染料废水处理方面具有良好的潜力. 展开更多
关键词 铁基MOF 氨基功能化 罗丹明b 吸附 氢键作用
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瑞马唑仑通过调控BDNF/TrkB信号通路影响衰老大鼠模型术后认知功能
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作者 吴振 马晓俞 《中国医科大学学报》 北大核心 2025年第9期781-785,共5页
目的 探究瑞马唑仑(Rem)对衰老大鼠模型术后认知功能的影响,以及对脑源性神经营养因子/酪氨酸激酶受体B(BDNF/TrkB)信号通路的调控机制。方法 将SD大鼠随机分为control组、model组、Rem-L组、Rem-M组、Rem-H组和Rem-H+7,8-DHF组。用Mor... 目的 探究瑞马唑仑(Rem)对衰老大鼠模型术后认知功能的影响,以及对脑源性神经营养因子/酪氨酸激酶受体B(BDNF/TrkB)信号通路的调控机制。方法 将SD大鼠随机分为control组、model组、Rem-L组、Rem-M组、Rem-H组和Rem-H+7,8-DHF组。用Morris水迷宫实验评估大鼠学习及记忆能力;用HE染色观察大鼠海马神经元的病理变化;用试剂盒检测大鼠血清炎性细胞因子白细胞介素(IL)-18、肿瘤坏死因子α(TNF-α)、IL-1β和脑组织中氧化应激指标[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、丙二醛(MDA)]水平;用Western blotting检测BDNF/TrkB信号轴相关蛋白及其下游信号分子的表达水平。结果 control组大鼠海马神经元细胞排列紧密、整齐,细胞边界、细胞质及细胞核较清晰,而model组大鼠海马神经元细胞则排列较紊乱,细胞形态不规则,部分细胞核呈固缩状态;model组较control组大鼠逃避潜伏期增加(P<0.05),血清IL-1β、IL-18、TNF-α表达水平及脑组织中MDA、BDNF、TrkB、p-AKT/AKT、ERK1表达水平升高(P<0.05),SOD、GSH水平降低(P<0.05);Rem-L组、Rem-M组和Rem-H组较model组大鼠海马神经元细胞逐渐趋于有序,损伤细胞数逐渐减少(P<0.05),逃避潜伏期逐渐缩短(P<0.05),血清IL-1β、IL-18、TNF-α表达水平及脑组织中MDA、BDNF、TrkB表达水平逐渐降低(P<0.05),SOD、GSH水平逐渐升高(P<0.05);BDNF/TrkB激活剂7,8-DHF逆转了Rem对衰老大鼠术后认知功能的调控作用(P<0.05)。结论 Rem能够调控衰老大鼠术后认知功能,其作用机制可能与BDNF/TrkB信号通路被抑制有关。 展开更多
关键词 瑞马唑仑 脑源性神经营养因子/酪氨酸激酶受体b 衰老 术后认知功能
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Effects of Lactobacillus paracasei N1115 on gut microbial imbalance and liver function in patients with hepatitis B-related cirrhosis 被引量:3
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作者 Yan-Chao Hu Xiang-Chun Ding +3 位作者 Hui-Juan Liu Wan-Long Ma Xue-Yan Feng Li-Na Ma 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1556-1571,共16页
BACKGROUND Hepatitis B cirrhosis(HBC)is a chronic disease characterized by irreversible diffuse liver damage and aggravated by intestinal microbial imbalance and metabolic dysfunction.Although the relationship between... BACKGROUND Hepatitis B cirrhosis(HBC)is a chronic disease characterized by irreversible diffuse liver damage and aggravated by intestinal microbial imbalance and metabolic dysfunction.Although the relationship between certain single probiotics and HBC has been explored,the impact of the complex ready-to-eat Lactobacillus paracasei N1115(LP N1115)supplement on patients with HBC has not been determined.AIM To compare the changes in the microbiota,inflammatory factor levels,and liver function before and after probiotic treatment in HBC patients.METHODS This study included 160 HBC patients diagnosed at the General Hospital of Ningxia Medical University between October 2018 and December 2020.Patients were randomly divided into an intervention group that received LP N1115 supplementation and routine treatment and a control group that received routine treatment only.Fecal samples were collected at the onset and conclusion of the 12-wk intervention period.The structure of the intestinal microbiota and the levels of serological indicators,such as liver function and inflammatory factors,were assessed.RESULTS Following LP N1115 intervention,the intestinal microbial diversity significantly increased in the intervention group(P<0.05),and the structure of the intestinal microbiota was characterized by an increase in the proportions of probiotic microbes and a reduction in harmful bacteria.Additionally,the intervention group demonstrated notable improvements in liver function indices and significantly lower levels of inflammatory factors(P<0.05).CONCLUSION LP N1115 is a promising treatment for ameliorating intestinal microbial imbalance in HBC patients by modulating the structure of the intestinal microbiota,improving liver function,and reducing inflammatory factor levels. 展开更多
关键词 Hepatitis b cirrhosis N1115 ready-to-eat lactobacillus Inflammation Liver function Lachnospiraceae incertae sedis Probiotic
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Functional cure of chronic hepatitis B-hope or hype? 被引量:1
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作者 Gautam Ray 《World Journal of Hepatology》 2024年第9期1199-1205,共7页
Chronic hepatitis B constitutes a substantial disease burden worldwide.The steps advocated by the World Health Organization in 2016 to eradicate hepatitis B by 2030 has failed to achieve significant progress,especiall... Chronic hepatitis B constitutes a substantial disease burden worldwide.The steps advocated by the World Health Organization in 2016 to eradicate hepatitis B by 2030 has failed to achieve significant progress,especially with respect to immu-nization coverage and linkage to care.The lack of governmental and public awar-eness regarding the long-term implications of hepatitis B burden cause under-funding of developmental projects.The presently approved treatment modalities have limited efficacy in complete viral eradication,hence the need for newer molecules to achieve functional cure(sustained undetectable hepatitis B surface antigen(HBsAg)and hepatitis B virus DNA in peripheral blood after a finite period of therapy).However,preliminary results from trials of novel therapies show their inadequacy to achieve this end by themselves but better performance with a low baseline serum HBsAg with nucleos(t)ide analogues(NA)treatment which need to be combined with/without pegylated interferon as an immu-nomodulator.Such therapy is limited by cost and adverse events and need to show incremental benefit over the standard of care(long-term NA therapy)with respect to efficacy and drug toxicities,making the development process tenuous.Thus,while such therapies continue to be tested,strategies should still focus on prevention of transmission by non-pharmaceutical measures,vaccination and increasing linkage to care. 展开更多
关键词 Hepatitis b DRUGS Clinical trial THERAPY Novel therapies functional cure
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B族链球菌感染对妊娠晚期孕妇凝血功能炎性因子及母婴结局的影响
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作者 王昆 郝栋栋 《中国妇幼保健》 2025年第8期1456-1459,共4页
目的 探讨B族链球菌(GBS)感染对妊娠晚期孕妇凝血功能、炎性因子及母婴结局的影响。方法 选取2021年1月—2023年1月于山东大学妇幼保健院进行产检的妊娠晚期GBS感染阳性孕妇98例纳入观察组,另选取同期产检的妊娠晚期GBS阴性孕妇50例纳入... 目的 探讨B族链球菌(GBS)感染对妊娠晚期孕妇凝血功能、炎性因子及母婴结局的影响。方法 选取2021年1月—2023年1月于山东大学妇幼保健院进行产检的妊娠晚期GBS感染阳性孕妇98例纳入观察组,另选取同期产检的妊娠晚期GBS阴性孕妇50例纳入对照组,观察两组分娩时羊水及脐带血的GBS感染情况,比较两组血清炎性因子及凝血功能指标水平,记录两组妊娠结局及新生儿GBS感染情况,应用多因素logistic法分析炎性因子与不良妊娠结局的关系。结果 观察组分娩时羊水GBS阳性感染率为36.73%(36/98),脐带血GBS阳性感染率为37.76%(37/98),均高于对照组(P<0.05);与对照组比较,观察组血清IL-8、TNF-α、PCT及hs-CRP水平明显升高[(96.34±15.87)vs.(20.49±3.98)ng/L,(71.02±13.49)vs.(23.68±4.11)ng/L,(5.83±1.76)vs.(1.17±0.32)μg/L,(57.64±14.39)vs.(16.03±2.86)mg/L,P<0.05];[(3.91±1.32)vs.(2.53±0.87)g/L,P<0.001],而血浆凝血酶原时间、活化部分凝血活酶时间及国际标准化比值明显缩短[(9.48±1.26)vs.(11.84±1.51)s,(25.45±3.16)vs.(28.97±4.08)s,(0.93±0.06)vs.(1.04±0.12),P<0.001];与对照组比较,观察组胎儿窘迫、胎膜早破、产褥感染、新生儿感染及剖宫产等不良结局发生率明显升高(P<0.05);IL-8、TNF-α、PCT及hs-CRP为影响妊娠晚期GBS感染阳性孕妇出现不良妊娠结局的危险因素(P<0.001)。结论 妊娠晚期感染GBS可影响孕妇机体凝血功能及血清炎性因子水平,该类孕妇分娩时羊水及脐带血GBS阳性感染率较高,临床应密切关注妊娠晚期GBS感染阳性孕妇凝血功能及血清炎性因子水平,以降低不良妊娠结局的发生风险。 展开更多
关键词 妊娠晚期 b族链球菌 凝血功能 炎性因子 母婴结局
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KD合并MP感染患儿心肌功能与血清Lp-PLA2、NT-proBNP、PCT水平及凝血指标的关系
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作者 薛峥峰 刘庆 +1 位作者 钟红平 李芳 《国际医药卫生导报》 2025年第13期2197-2201,共5页
目的探究川崎病(KD)合并肺炎支原体(MP)感染患儿心肌功能与血清脂蛋白磷脂酶A2(Lp-PLA2)、N-末端脑利钠肽原(NT-proBNP)、降钙素原(PCT)水平及凝血指标的关系。方法选取2020年1月至2024年1月延安大学附属医院收治的80例KD患儿作为研究... 目的探究川崎病(KD)合并肺炎支原体(MP)感染患儿心肌功能与血清脂蛋白磷脂酶A2(Lp-PLA2)、N-末端脑利钠肽原(NT-proBNP)、降钙素原(PCT)水平及凝血指标的关系。方法选取2020年1月至2024年1月延安大学附属医院收治的80例KD患儿作为研究对象。检测患儿MP感染情况,并以此进行分组,31例合并MP感染患儿纳入合并感染组,剩余49例患儿纳入未合并组。合并感染组男18例,女13例;年龄(3.16±1.22)岁。未合并组男29例,女20例;年龄(3.72±1.45)岁。比较两组临床资料(年龄、最高体温、发热持续时间、球结膜充血、口唇干裂、杨梅舌、口腔黏膜充血、躯干皮疹、四肢红斑、四肢水肿、指端脱皮、肛周脱皮、颈部淋巴结肿大)和实验室指标(肌酸激酶、肌酸激酶同工酶、乳酸脱氢酶、α-羟丁酸脱氢酶、天门冬氨酸氨基转移酶、NT-proBNP、Lp-PLA2、PCT、凝血酶原时间、活化部分凝血酶原时间、纤维蛋白原定量、凝血时间、抗凝血酶Ⅲ、D-二聚体)。采用独立样本t检验和χ^(2)检验进行统计学分析。采用Pearson相关性分析心肌功能与血清Lp-PLA2、NT-proBNP、PCT水平及凝血指标的关系。结果两组临床资料比较,差异均无统计学意义(均P>0.05)。两组肌酸激酶、乳酸脱氢酶、α-羟丁酸脱氢酶、天门冬氨酸氨基转移酶水平比较,差异均无统计学意义(均P>0.05);合并感染组肌酸激酶同工酶水平高于未合并组[(42.88±5.78)U/L比(30.88±7.12)U/L](P<0.05)。两组血清NT-proBNP水平比较,差异无统计学意义(P>0.05);合并感染组血清Lp-PLA2、PCT水平均高于未合并组[(543.80±121.12)μg/L比(466.15±116.15)μg/L、(0.88±0.21)μg/L比(0.44±0.15)μg/L](均P<0.05)。两组凝血酶原时间、活化部分凝血酶原时间、纤维蛋白原定量、凝血时间、抗凝血酶Ⅲ水平比较,差异均无统计学意义(均P>0.05);合并感染组D-二聚体水平高于未合并组[(855.12±124.41)μg/L比(744.15±110.15)μg/L](P<0.05)。Pearson相关性分析显示,肌酸激酶同工酶水平与血清Lp-PLA2、PCT、D-二聚体水平呈正相关,α-烃丁酸脱氢酶水平与血清NT-proBNP水平呈正相关,天门冬氨酸氨基转移酶水平与血清PCT水平呈正相关(均P<0.05)。结论KD合并MP感染患儿心肌功能受损较严重,且影响患儿炎症反应及凝血功能,具体表现为肌酸激酶同工酶、血清Lp-PLA2、PCT、D-二聚体水平升高,心肌酶与炎症、凝血功能指标存在正相关关系。 展开更多
关键词 肺炎支原体 川崎病 心肌功能 脂蛋白磷脂酶A2 N-末端脑利钠肽原 降钙素原 凝血指标
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 被引量:4
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients PIECEWISE POLYNOMIAL functionS CUbIC splines Curve fitting PIECEWISE linear functionS PIECEWISE CUbIC HERMITE interpolating POLYNOMIAL PROJECTILE modelling and simulation Fire control inputs Precision ballistic computer software
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