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低铼MHC合金组织和性能研究
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作者 董帝 宋辉煌 +6 位作者 刘洁 李洪涛 李兆森 王承阳 熊宁 张丹华 吴昊阳 《中国钼业》 2026年第1期73-84,共12页
纯Mo的低温脆性、室温塑性不足和再结晶脆化等制约了其发展和应用,引入HfC弥散相形成MHC合金可细化Mo晶粒、吸收杂质O等,从而提高力学性能。但BCC结构的Mo独立滑移系少,HfC对塑韧性改善有限且无加工硬化,而Re可以促进Mo多滑移系、降低... 纯Mo的低温脆性、室温塑性不足和再结晶脆化等制约了其发展和应用,引入HfC弥散相形成MHC合金可细化Mo晶粒、吸收杂质O等,从而提高力学性能。但BCC结构的Mo独立滑移系少,HfC对塑韧性改善有限且无加工硬化,而Re可以促进Mo多滑移系、降低局部应力集中,以促进MHC合金均匀变形,但Re昂贵。因此本文采用粉末冶金法制备低铼(≤5%,质量分数)MHC合金,分析了低Re对MHC合金微观组织和力学性能的影响,结果表明:Re促进烧结致密化和变形取向多样化,显著细化晶粒尺寸,促进小角度晶界形成但抑制动态回复,并促使MHC合金室温拉伸出现屈服现象。3%(质量分数)Re合金具有优异显微组织和力学性能:变形横向具有最小晶粒尺寸2.24μm、最高再结晶组织占比68.7%、高施密特因子0.473及最低几何必要位错密度7.90×10^(13) m^(-2);室温拉伸加工硬化明显,屈服强度高为876.2 MPa;高温(2 000 K)抗拉强度和屈服强度最高分别为283.1 MPa和268.4 MPa,断后伸长率为20.5%,热稳定性高。 展开更多
关键词 mhc合金 变形 组织 性能
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LAG3 facilitates MHC Ⅱ trogocytosis with assistance of the ERPM junction
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作者 Zibin Wang Jing Wang +1 位作者 Wene Zhao Wen Liu 《Journal of Biomedical Research》 2026年第1期89-92,共4页
Dear Editor,Lymphocyte activation gene 3(LAG3),the third established target for immune checkpoint blockade therapy,suppresses T cell function by binding to major histocompatibility complex classⅡ(MHCⅡ).Despite its s... Dear Editor,Lymphocyte activation gene 3(LAG3),the third established target for immune checkpoint blockade therapy,suppresses T cell function by binding to major histocompatibility complex classⅡ(MHCⅡ).Despite its significant therapeutic potential in cancer immunotherapy and the substantial attention it has received from academia and industry,the molecular mechanisms of LAG3-mediated immunosuppression remain poorly understood,primarily because of its unique ligand-binding characteristics and intracellular domains[1]. 展开更多
关键词 LAG IMMUNOSUPPRESSION cancer immunotherapy immune checkpoint blockade therapysuppresses t cell function ERPM TROGOCYTOSIS mhc
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A mesoscale stress-damage-seepage coupling model of hydraulic asphalt concrete incorporating the damage-dependent permeability coefficient of asphalt mortar
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作者 Nanxuan Qian Wei Luo +3 位作者 Bingyu Mei Desheng Yin Yixin Feng Hui Peng 《Acta Mechanica Sinica》 2026年第1期192-208,共17页
Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is partic... Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is particularly prone to damage under combined stress and seepage interactions,and the mesoscale investigations on the damage-seepage coupling behavior of HAC under complex stress states remain limited.This research develops a numerical three-dimensional mesoscale model composed of asphalt mortar and polyhedral aggregate to investigate the stress-damage-seepage coupling behavior in HAC.In this model,asphalt mortar yields the viscoelastic continuum damage law and aggregate obeys the Mazars’elastic-brittle damage law;simultaneously,the effective permeability coefficient of asphalt mortar is assumed to follow an exponential function of damage.The predicted deviatoric stress-strain and hydraulic gradient-seepage curves both are in good agreement with the reported experimental results,which shows the proposed model is valid and reasonable.The simulated results indicate that the damaged asphalt mortar can induce localized areas of high permeability,which in turn affects the overall impervious performance of HAC. 展开更多
关键词 Effective permeability coefficient Viscoelastic continuum damage Stress-seepage coupling
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Neutron‑gamma density measurement method using the mass attenuation coefficient function
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作者 Jun‑Yan Chen Qiong Zhang 《Nuclear Science and Techniques》 2026年第1期180-192,共13页
Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging tec... Although traditional gamma-gamma density(GGD)logging technology is widely utilized,its potential environmental risks have prompted the development of more environmentally friendly neutron-gamma density(NGD)logging technology.However,NGD measurements are influenced by both neutron and gamma radiations.In the logging environment,variations in the formation composition indicate different elemental compositions,which affect the neutron-gamma reaction cross-sections and gamma generation.Compared to traditional gamma sources such as Cs-137,these changes significantly affect the generation and transport of neutron-induced inelastic gamma rays and hinder accurate measurements.To address this,a novel method is proposed that incorporates the mass attenuation coefficient function to account for the effects of various lithologies and pore contents on gamma-ray attenuation,thereby achieving more accurate density measurements by clarifying the transport processes of inelastic gamma rays with varying energies and spatial distributions in varied logging environments.The proposed method avoids the complex correction of neutron transport and is verified through Monte Carlo simulations for its applicability across various lithologies and pore contents,demonstrating absolute density errors that are less than 0.02 g/cm^(3)in clean formations and indicating good accuracy.This study clarifies the NGD mechanism and provides theoretical guidance for the application of NGD logging methods.Further studies will be conducted on extreme environmental conditions and tool calibration. 展开更多
关键词 Neutron-gamma density Mass attenuation coefficient Monte Carlo simulation
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HfC硬质掺杂对高能球磨过程中MHC合金粉体形貌及显微结构的影响
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作者 王苗 杨双平 +4 位作者 刘起航 董洁 范博文 张紫涵 刘雅辰 《稀有金属》 北大核心 2025年第12期1910-1919,共10页
本文采用干法直接掺杂粉末冶金工艺制备了HfC掺杂钼-铪-碳(MHC)钼合金棒材,为掌握硬质掺杂对合金粉体形貌及分布均匀性的影响,利用X射线衍射仪(XRD)、扫描电镜(SEM)、透射电镜(TEM)对粉体形貌、物相及元素分布进行了分析,总结了硬质掺... 本文采用干法直接掺杂粉末冶金工艺制备了HfC掺杂钼-铪-碳(MHC)钼合金棒材,为掌握硬质掺杂对合金粉体形貌及分布均匀性的影响,利用X射线衍射仪(XRD)、扫描电镜(SEM)、透射电镜(TEM)对粉体形貌、物相及元素分布进行了分析,总结了硬质掺杂对合金粉体制备过程的影响规律。结果表明:单独球磨Mo粉无法遗传球状形貌;掺杂硬质HfC的MHC合金混合粉体属于延性—脆性体系,Mo粉的球状形貌因硬质HfC的掺杂而得到遗传,且HfC粉体获得了比Mo粉更好的细化效果;细小的HfC粉体活性高、表面能大,易于在球磨过程中镶嵌或冶金焊合于延性的Mo粉颗粒上,使粉体处于高能状态;过长的球磨时间不易于获得粒度分布、形貌等指标与能耗指标之间的平衡,现有的球磨工艺条件下,5.5 h正反转间歇式球磨可获得最优混匀效果。 展开更多
关键词 钼-铪-碳(mhc)合金 粉末冶金 HfC掺杂 高能球磨 第二相分散性 球状形貌
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复方浙贝颗粒基于MDM2/p53信号通路调节MHC-Ⅱ逆转白血病多药耐药机制研究 被引量:1
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作者 杨茜茹 田劭丹 +6 位作者 薛程元 李光达 张雅月 张宇 李冬云 齐宇镈 侯丽 《北京中医药》 2025年第3期325-330,共6页
目的 探讨复方浙贝颗粒(CZBG)基于双微体同源基因2(MDM2)/p53信号通路调节主要组织相容性复合体Ⅱ类(MHC-Ⅱ)逆转白血病多药耐药的作用机制。方法 选取人急性髓系白血病细胞(KG-1a、MOLM-13细胞),将KG-1a、MOLM-13细胞分别分为CZBG组、... 目的 探讨复方浙贝颗粒(CZBG)基于双微体同源基因2(MDM2)/p53信号通路调节主要组织相容性复合体Ⅱ类(MHC-Ⅱ)逆转白血病多药耐药的作用机制。方法 选取人急性髓系白血病细胞(KG-1a、MOLM-13细胞),将KG-1a、MOLM-13细胞分别分为CZBG组、空白对照组。空白对照组予完全培养基培养,CZBG组予含不同浓度的CZBG完全培养基培养。CCK-8法检测细胞增殖,Western blotting法检测MDM2、p53蛋白表达,流式细胞术检测MHC-Ⅱ表达。结果 干预24、48、72 h,CZBG对KG-1a、MOLM-13细胞增殖均具有抑制作用。其中CZBG在24、48、72 h时对KG-1a细胞的半数抑制浓度(IC50)为(2.276±0.218)、(1.254±0.104)、(1.040±0.108)mg/mL,对MOLM-13细胞的IC50为(2.809±0.121)、(1.585±0.103)、(1.194±0.105)mg/mL。应用2.2 mg/mL CZBG干预KG-1a细胞24 h时,与空白对照组比较,CZBG组MDM2蛋白相对表达量低(P<0.05),p53蛋白相对表达量高(P<0.05)。用2.8 mg/mL CZBG干预MOLM-13细胞24 h时,与空白对照组比较,CZBG组MDM2蛋白表达低(P<0.05),p53蛋白相对表达量高(P<0.05)。KG-1a、MOLM-13细胞分别经CZBG处理24 h,CZBG组细胞表面的MHC-Ⅱ表达高(P<0.05)。结论 CZBG逆转白血病多药耐药的作用机制可能与通过MDM2/p53通路调节白血病细胞表面MHC-Ⅱ表达,干预免疫逃逸有关。 展开更多
关键词 复方浙贝颗粒 双微体同源基因2(MDM2)/p53信号通路 主要组织相容性复合体Ⅱ类 白血病 多药耐药 作用机制
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MHC-Ⅰ和MHC-Ⅱ在弥漫大B细胞淋巴瘤中的表达与临床病理特征关系及预后的影响
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作者 李君娜 于靖雯 +6 位作者 王小树 马文梅 庞雪莲 马明福 薛晶 张巍 崔文丽 《诊断病理学杂志》 2025年第6期635-642,共8页
目的本研究旨在探讨弥漫大B细胞淋巴瘤(DLBCL)中主要组织相容性复合体(MHC)Ⅰ、Ⅱ表达及其与临床病理特征及预后的相关性。方法收集新疆医科大学第一附属医院病理科DLBCL 130例,采用免疫组化EnVision法检测MHC-Ⅰ、MHC-Ⅱ蛋白表达情况,... 目的本研究旨在探讨弥漫大B细胞淋巴瘤(DLBCL)中主要组织相容性复合体(MHC)Ⅰ、Ⅱ表达及其与临床病理特征及预后的相关性。方法收集新疆医科大学第一附属医院病理科DLBCL 130例,采用免疫组化EnVision法检测MHC-Ⅰ、MHC-Ⅱ蛋白表达情况,分析二者相关性及其与DLBCL临床病理特征和预后的关系。结果(1)免疫组化染色结果显示,DLBCL肿瘤细胞中MHC-Ⅰ、MHC-Ⅱ低表达率分别为57.6%(68/118)和40.3%(48/119)。(2)MHC-Ⅰ低表达与Ann-Arbor分期、PS评分、发生部位相关(P<0.05),MHC-Ⅱ低表达与年龄、结外受累病灶相关(P<0.05),MHC-Ⅰ/MHC-Ⅱ共高表达与骨髓不易受累相关(P<0.05)。(3)Kaplan-Meier单因素生存结果显示MHC-Ⅱ低表达组预后差(P<0.05),MHC-Ⅰ对生存无显著影响(P>0.05),多因素COX回归分析显示LDH、PS评分、IPI评分是影响DLBCL患者的独立危险因素。结论MHC-Ⅰ和MHC-Ⅱ在DLBCL中低表达,与Ann-Arbor分期、PS评分、发生部位、年龄、结外受累病灶相关。MHC-Ⅱ低表达的DLBCL患者预后较差。 展开更多
关键词 弥漫大B细胞淋巴瘤 主要组织相容性复合体 mhcⅠ类分子 mhcⅡ类分子 临床病理特征
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鸡MHC基因家族鉴定与分析
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作者 葛华梁 任敏鹏 +4 位作者 张夕霏 杨姣 耿立英 张传生 李祥龙 《中国畜牧杂志》 北大核心 2025年第11期159-170,共12页
本研究旨在对鸡主要组织相容复合物(Major Histocompatibility Complex,MHC)基因家族进行生物信息学分析,明确鸡感染马立克氏病毒(Marek's Disease Virus,MDV)和注射羊红细胞(Sheep Red Blood Cells,SRBC)后MHC基因家族成员的表达... 本研究旨在对鸡主要组织相容复合物(Major Histocompatibility Complex,MHC)基因家族进行生物信息学分析,明确鸡感染马立克氏病毒(Marek's Disease Virus,MDV)和注射羊红细胞(Sheep Red Blood Cells,SRBC)后MHC基因家族成员的表达模式。通过生物信息学工具构建跨物种系统进化树,分析鸡MHC蛋白的理化性质、亚细胞定位、染色体分布、保守结构域、共线性、顺式作用元件,并构建蛋白质互作网络,进行蛋白质三维结构建模。进一步分析鸡感染MDV和SRBC免疫应答后鸡脾脏中MHC基因的表达变化。研究共鉴定出49个鸡MHC基因家族成员,鸡MHC基因均密集分布于第16号染色体的特定区域,与日本鹌鹑亲缘关系最近。共线性分析发现其中存在2次串联重复和片段重复事件。蛋白特性分析发现MHC基因编码的蛋白具有1~2个跨膜结构域,均含有免疫球蛋白超家族保守结构域,且主要定位于内质网和质膜。顺式元件分析发现MHC基因启动子区富含C/EBPα、NF-1等免疫相关调控位点,蛋白质互作网络分析发现BF2为枢纽节点。三维结构建模显示经典MHC I闭合槽结构适配内源肽段呈递,II类开放槽结构呈递外源肽段,而非经典基因(如MHCY)与BG基因可能通过非经典途径调控免疫应答。正选择分析发现鸟类特有的BG基因受到自然和人工的选择压力。转录组数据表明鸡感染MDV后大部分MHC基因的表达量上调。qRT-PCR分析表明鸡在SRBC免疫应答后,MHC基因(BF1、BF2、BLB2和DMB2)表达显著上调。 展开更多
关键词 mhc基因家族 生物信息学 系统进化 免疫应答
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中国花鲈IgM重链(IgMH)和MHCⅡβ基因的克隆及表达分析
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作者 雷丽娜 高谦 +3 位作者 王伟 孙兆盛 罗璋 刘其根 《水产学报》 北大核心 2025年第6期24-41,共18页
【目的】进一步了解中国花鲈适应性免疫机制在病害防治中的作用。【方法】本研究通过荧光定量PCR(RT-PCR)和快速扩增c DNA末端(RACE)技术克隆获得了免疫球蛋白M重链(IgMH)和主要组织兼容性复合体MHC Ⅱβ基因的全长;通过实时荧光定量PCR... 【目的】进一步了解中国花鲈适应性免疫机制在病害防治中的作用。【方法】本研究通过荧光定量PCR(RT-PCR)和快速扩增c DNA末端(RACE)技术克隆获得了免疫球蛋白M重链(IgMH)和主要组织兼容性复合体MHC Ⅱβ基因的全长;通过实时荧光定量PCR(RT-qPCR)检测其在中国花鲈各组织的分布情况以及LPS、Poly(I:C)刺激及迟缓爱德华氏菌人工感染后其对应mRNA水平的表达变化情况;实验构建了IgMH-pET21d、IgMCH1-2-pET21d和MHCⅡβ-pET21d原核重组表达质粒,进行重组蛋白表达,并通过分子筛层析技术纯化中国花鲈IgMH、IgMCH1-2和MHCⅡβ重组蛋白,进而制备了抗中国花鲈IgMH的多克隆抗体。【结果】中国花鲈IgMH和MHCⅡβ的cDNA全长分别为1977 bp和1242 bp;二者在鳃、脾脏和头肾等免疫相关组织中对应mRNA表达量较高;LPS、Poly(I:C)刺激及迟缓爱德华氏菌人工感染中国花鲈导致鳃、脾脏和头肾中这两个基因的表达水平发生显著变化,表明IgMH和MHCⅡβ均参与了中国花鲈的抗感染免疫反应;此外,抗中国花鲈IgM的多克隆抗体能与中国花鲈全血清发生强烈反应,与鳜全血清弱反应,与大口黑鲈和草鱼血清不发生反应,推测其反应强度反映了物种间亲缘关系的远近。【结论】本研究首次克隆了中国花鲈的IgMH和MHCⅡβ基因全长,表达了IgMH和MHCⅡβ原核重组蛋白,制备了抗中国花鲈IgM的多克隆抗体,揭示了IgMH和MHCⅡβ参与中国花鲈的抗感染免疫应答,为深入研究中国花鲈的免疫调控机制和疾病防控策略奠定了基础。 展开更多
关键词 中国花鲈 IgMH mhcⅡβ 表达调控 蛋白纯化
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Absorption-Reflection-Transmission Power Coefficient Guiding Gradient Distribution of Magnetic MXene in Layered Composites for Electromagnetic Wave Absorption 被引量:3
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作者 Yang Zhou Wen Zhang +7 位作者 Dong Pan Zhaoyang Li Bing Zhou Ming Huang Liwei Mi Chuntai Liu Yuezhan Feng Changyu Shen 《Nano-Micro Letters》 2025年第6期466-481,共16页
The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electrom... The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electromagnetic component regulation,layered arrangement structure,and gradient concentration distribution was used to optimize impedance matching and enhance electromagnetic loss.On the microscale,the incorporation of magnetic Ni nanoparticles into MXene nanosheets(Ni@MXene)endows suitable intrinsic permittivity and permeability.On the macroscale,the layered arrangement of Ni@MXene increases the effective interaction area with electromagnetic waves,inducing multiple reflection/scattering effects.On this basis,according to the analysis of absorption,reflection,and transmission(A-R-T)power coefficients of layered composites,the gradient concentration distribution was constructed to realize the impedance matching at low-concentration surface layer,electromagnetic loss at middle concentration interlayer and microwave reflection at high-concentration bottom layer.Consequently,the layered gradient composite(LG5-10-15)achieves complete absorption coverage of X-band at thickness of 2.00-2.20 mm with RL_(min) of-68.67 dB at 9.85 GHz in 2.05 mm,which is 199.0%,12.6%,and 50.6%higher than non-layered,layered and layered descending gradient composites,respectively.Therefore,this work confirms the importance of layered gradient structure in improving absorption performance and broadens the design of high-performance microwave absorption materials. 展开更多
关键词 Magnetic MXene Layered and gradient structure Power coefficient Electromagnetic wave absorption
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Study on the variation of the permeability coefficient of soil-rock mixtures in fault zones under different stress states 被引量:1
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作者 Wenhui Tan Shuang Liang +1 位作者 Xuewen Ma Pengfei Wang 《Deep Underground Science and Engineering》 2025年第2期210-221,共12页
As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted ... As the first gold mine discovered at the sea in China and the only coastal gold mine currently mined there,Sanshandao Gold Mine faces unique challenges.The mine's safety is under continual threat from its faulted structure coupled with the overlying water.As the mining proceeds deeper,the risk of water inrush increases.The mine's maximum water yield reaches 15000 m3/day,which is attributable to water channels present in fault zones.Predominantly composed of soil–rock mixtures(SRM),these fault zones'seepage characteristics significantly impact water inrush risk.Consequently,investigating the seepage characteristics of SRM is of paramount importance.However,the existing literature mostly concentrates on a single stress state.Therefore,this study examined the characteristics of the permeability coefficient under three distinct stress states:osmotic,osmotic–uniaxial,and osmotic–triaxial pressure.The SRM samples utilized in this study were extracted from in situ fault zones and then reshaped in the laboratory.In addition,the micromechanical properties of the SRM samples were analyzed using computed tomography scanning.The findings reveal that the permeability coefficient is the highest under osmotic pressure and lowest under osmotic–triaxial pressure.The sensitivity coefficient shows a higher value when the rock block percentage ranges between 30%and 40%,but it falls below 1.0 when this percentage exceeds 50%under no confining pressure.Notably,rock block percentages of 40%and 60%represent the two peak points of the sensitivity coefficient under osmotic–triaxial pressure.However,SRM samples with a 40%rock block percentage consistently show the lowest permeability coefficient under all stress states.This study establishes that a power function can model the relationship between the permeability coefficient and osmotic pressure,while its relationship with axial pressure can be described using an exponential function.These insights are invaluable for developing water inrush prevention and control strategies in mining environments. 展开更多
关键词 permeability coefficient rock block percentage sensitivity analysis soil-rock mixture stress state
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Numerical Methods for Boundary Value Problems in Variable Coefficient Ordinary Differential Equations 被引量:1
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作者 ZHAO Ting-ting CAI Wei-yun 《Chinese Quarterly Journal of Mathematics》 2025年第3期295-303,共9页
In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error... In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation. 展开更多
关键词 Variable coefficient ordinary differential equations Lagrange interpolation Difference methods
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Role of disturbance coefficient in monitoring and treatment of cerebral edema in patients with cerebral hemorrhage 被引量:1
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作者 Wen-Wen Gao Xiao-Bing Jiang +9 位作者 Peng Chen Liang Zhang Lei Yang Zhi-Hai Yuan Yao Wei Xiao-Qiang Li Xiao-Lu Tang Feng-Lu Wang Hao Wu Hai-Kang Zhao 《World Journal of Clinical Cases》 2025年第14期16-24,共9页
BACKGROUND At present,the conventional methods for diagnosing cerebral edema in clinical practice are computed tomography(CT)and magnetic resonance imaging(MRI),which can evaluate the location and degree of peripheral... BACKGROUND At present,the conventional methods for diagnosing cerebral edema in clinical practice are computed tomography(CT)and magnetic resonance imaging(MRI),which can evaluate the location and degree of peripheral cerebral edema,but cannot realize quantification.When patients have symptoms of diffuse cerebral edema or high cranial pressure,CT or MRI often suggests that cerebral edema is lagging and cannot be dynamically monitored in real time.Intracranial pressure monitoring is the gold standard,but it is an invasive operation with high cost and complications.For clinical purposes,the ideal cerebral edema monitoring should be non-invasive,real-time,bedside,and continuous dynamic monitoring.The dis-turbance coefficient(DC)was used in this study to dynamically monitor the occu-rrence,development,and evolution of cerebral edema in patients with cerebral hemorrhage in real time,and review head CT or MRI to evaluate the development of the disease and guide further treatment,so as to improve the prognosis of patients with cerebral hemorrhage.AIM To offer a promising new approach for non-invasive adjuvant therapy in cerebral edema treatment.METHODS A total of 160 patients with hypertensive cerebral hemorrhage admitted to the Department of Neurosurgery,Second Affiliated Hospital of Xi’an Medical University from September 2018 to September 2019 were recruited.The patients were randomly divided into a control group(n=80)and an experimental group(n=80).Patients in the control group received conventional empirical treatment,while those in the experimental group were treated with mannitol dehydration under the guidance of DC.Subsequently,we compared the two groups with regards to the total dosage of mannitol,the total course of treatment,the incidence of complications,and prognosis.RESULTS The mean daily consumption of mannitol,the total course of treatment,and the mean hospitalization days were 362.7±117.7 mL,14.8±5.2 days,and 29.4±7.9 in the control group and 283.1±93.6 mL,11.8±4.2 days,and 23.9±8.3 in the experimental group(P<0.05).In the control group,there were 20 patients with pulmonary infection(25%),30 with electrolyte disturbance(37.5%),20 with renal impairment(25%),and 16 with stress ulcer(20%).In the experimental group,pulmonary infection occurred in 18 patients(22.5%),electrolyte disturbance in 6(7.5%),renal impairment in 2(2.5%),and stress ulcers in 15(18.8%)(P<0.05).According to the Glasgow coma scale score 6 months after discharge,the prognosis of the control group was good in 20 patients(25%),fair in 26(32.5%),and poor in 34(42.5%);the prognosis of the experimental group was good in 32(40%),fair in 36(45%),and poor in 12(15%)(P<0.05).CONCLUSION Using DC for non-invasive dynamic monitoring of cerebral edema demonstrates considerable clinical potential.It reduces mannitol dosage,treatment duration,complication rates,and hospital stays,ultimately lowering hospital-ization costs.Additionally,it improves overall patient prognosis,offering a promising new approach for non-invasive adjuvant therapy in cerebral edema treatment. 展开更多
关键词 Noninvasive cerebral edema monitor Disturbance coefficient HYPERTENSION Cerebral hemorrhage Cerebral edema MANNITOL
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Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi 被引量:1
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作者 Nadeem Iqbal Aisha Hasan +2 位作者 Sajid Iqbal Sadaf Noureen Saeed Akhter 《World Journal of Nephrology》 2025年第1期110-118,共9页
BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free r... BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes. 展开更多
关键词 Computed tomography Shock wave lithotripsy Stone heterogeneity Variation coefficient of stone density Kidney stones
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Prediction of joint roughness coefficient via hybrid machine learning model combined with principal components analysis 被引量:1
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作者 Shijie Xie Hang Lin +2 位作者 Tianxing Ma Kang Peng Zhen Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2291-2306,共16页
Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC... Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC is a nonlinear system with a lot of overlapping information.In this paper,a dataset of eight roughness statistical parameters covering 112 digital joints is established.Then,the principal component analysis method is introduced to extract the significant information,which solves the information overlap problem of roughness characterization.Based on the two principal components of extracted features,the white shark optimizer algorithm was introduced to optimize the extreme gradient boosting model,and a new machine learning(ML)prediction model was established.The prediction accuracy of the new model and the other 17 models was measured using statistical metrics.The results show that the prediction result of the new model is more consistent with the real JRC value,with higher recognition accuracy and generalization ability. 展开更多
关键词 Rock discontinuities Joint roughness coefficient(JRC) Roughness characterization Principal components analysis(PCA) Machine learning
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A Programming Method for Mean Behavior of Fourier Coefficients of Modular Forms on Sparse Sequences
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作者 HU Yuanrui YAO Weili 《数学进展》 北大核心 2025年第4期709-724,共16页
Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)at... Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)attached to f.In this paper,we study the mean value distribution over a specific sparse sequence of positive integers of the following sum∑(a^(2)+b^(2)+c^(2)+d^(2)≤x(a,b,c,d)∈Z^(4))λ_(sym^(j))^(i)f(a^(2)+b^(2)+c^(2)+d^(2))where j≥2 is a given positive integer,i=2,3,4 andαis sufficiently large.We utilize Python programming to design algorithms for higher power conditions,combining Perron's formula,latest results of representations of natural integers as sums of squares,as well as analytic properties and subconvexity and convexity bounds of automorphic L-functions,to ensure the accuracy and verifiability of asymptotic formulas.The conclusion we obtained improves previous results and extends them to a more general settings. 展开更多
关键词 automorphic L-function holomorphic cusp form Fourier coefficient
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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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Growth Parameters and Condition Coefficient of Three Species from Bas-Kouilou (Congo Brazzaville): Chrysichthys auratus, Geoffroy, 1809, Liza falcipinnis, Valenciennes, 1836 and Pellonula vorax, Gunther, 1868
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作者 Marcellin Mikia Anthelme Tsoumou +1 位作者 Durelle Brith Caëlle Olabi-Obath Isabelle Mady-Goma Dirat 《Open Journal of Ecology》 2025年第1期100-114,共15页
The study of the morphometric parameters of the three most abundant species in the lower course of the Kouilou River (Chrysichthys auratus, Liza falcipinnis and Pellonula vorax) was carried out. The standard length of... The study of the morphometric parameters of the three most abundant species in the lower course of the Kouilou River (Chrysichthys auratus, Liza falcipinnis and Pellonula vorax) was carried out. The standard length of Chrysichthys auratus varies between 43.57 and 210 mm, for an average of 96.70 ± 28.63 mm;the weight varies between 2.92 and 140.83 mg, an average of 73.03 ± 21.62 mg. The condition coefficient is equal to 4.42 ± 1.52. Liza falcipinnis has a standard length which varies between 59.9 mm and 158.08 mm for an average of 88.15 ± 29.74 mm;its weight varies between 4.77 and 76.21 mg, an average of 18.61 ± 11.82 mg. The condition coefficient is equal to 2.47 ± 1.57. Pellonula vorax has a standard length which varies between 60.33 mm and 117.72 mm;for an average of 80.48 ± 17.75 mm;the weight varies between 3.61 and 25.17 mg, an average of 9.03 ± 3.61 mg. The condition coefficient is equal to 2.17 ± 0.57. These three species have a minor allometric growth. 展开更多
关键词 Kouilou River Chrysichthys auratus Liza falcipinnis Pellonula vorax Growth Parameters Condition coefficient
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Field system-level calibration method for accelerometer considering nonlinear coefficients
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作者 WU Haotian YU Ruihang +2 位作者 CAO Juliang MA Caixia YANG Bainan 《Journal of Systems Engineering and Electronics》 2025年第3期814-824,共11页
In order to get rid of the dependence on high-precision centrifuges in accelerometer nonlinear coefficients calibration,this paper proposes a system-level calibration method for field condition.Firstly,a 42-dimension ... In order to get rid of the dependence on high-precision centrifuges in accelerometer nonlinear coefficients calibration,this paper proposes a system-level calibration method for field condition.Firstly,a 42-dimension Kalman filter is constructed to reduce impact brought by turntable.Then,a biaxial rotation path is designed based on the accelerometer output model,including orthogonal 22 positions and tilt 12 positions,which enhances gravity excitation on nonlinear coefficients of accelerometer.Finally,sampling is carried out for calibration and further experiments.The results of static inertial navigation experiments lasting 4000 s show that compared with the traditional method,the proposed method reduces the position error by about 390 m. 展开更多
关键词 ACCELEROMETER nonlinear coefficient system-level calibration rotation path
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Variation coefficient of stone density – can it crack the stone?
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作者 Krishna Kumar Govindarajan 《World Journal of Nephrology》 2025年第3期1-3,共3页
Extracorporeal shock wave lithotripsy(ESWL)is recognised as the ideal noninvasive procedure for urolithiasis.However,the suitability of ESWL varies depending on the composition of the stone.The chemical structure of t... Extracorporeal shock wave lithotripsy(ESWL)is recognised as the ideal noninvasive procedure for urolithiasis.However,the suitability of ESWL varies depending on the composition of the stone.The chemical structure of the stone may not be uniform throughout the stone and this heterogeneity provides the clue in the form of variation coefficient of stone density.To be aware of the success of the stone breakage by ESWL is an advantage upfront,so that it is possible to apply the technology to the most appropriate patient.This is an important aspect in the successful management of urolithiasis. 展开更多
关键词 UROLITHIASIS Variation coefficient Stone density LITHOTRIPSY Renal stones
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