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Enhancing Lightweight Mango Disease Detection Model Performance through a Combined Attention Module
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作者 Wen-Tsai Sung Indra Griha TofikIsa Sung-Jung Hsiao 《Computers, Materials & Continua》 2026年第2期986-1016,共31页
Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this... Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this study,a lightweight object detection model will be developed that can detect mango plant conditions based on disease potential,so that it becomes an early detection warning system that has an impact on increasing agricultural productivity.The proposed lightweight model integrates YOLOv7-Tiny and the proposed modules,namely the C2S module.The C2S module consists of three sub-modules such as the convolutional block attention module(CBAM),the coordinate attention(CA)module,and the squeeze-and-excitation(SE)module.The dataset is constructed by eight classes,including seven classes of disease conditions and one class of health conditions.The experimental result shows that the proposed lightweight model has the optimal results,which increase by 13.15% of mAP50 compared to the original model YOLOv7-Tiny.While the mAP50:95 also achieved the highest results compared to other models,including YOLOv3-Tiny,YOLOv4-Tiny,YOLOv5,and YOLOv7-Tiny.The advantage of the proposed lightweightmodel is the adaptability that supports it in constrained environments,such as edge computing systems.This proposedmodel can support a robust,precise,and convenient precision agriculture system for the user. 展开更多
关键词 Mango lightweight model combined attention module c2s module precision agriculture
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Short-lived Niemann-Pick type C mice with accelerated brain aging as a novel model for Alzheimer’s disease research
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作者 Vikas Anil Gujjala Morteza Abyadeh +6 位作者 Isaiah Klimek Alexander Tyshkovskiy Naci Oz JoséPedro Castro Vadim N.Gladyshev Jason Newton Alaattin Kaya 《Neural Regeneration Research》 2026年第6期2531-2542,共12页
Alzheimer’s disease is initially thought to be caused by age-associated accumulation of plaques,in recent years,research has increasingly associated Alzheimer’s disease with lysosomal storage and metabolic disorders... Alzheimer’s disease is initially thought to be caused by age-associated accumulation of plaques,in recent years,research has increasingly associated Alzheimer’s disease with lysosomal storage and metabolic disorders,and the explanation of its pathogenesis has shifted from amyloid and tau accumulation to oxidative stress and impaired lipid and glucose metabolism aggravated by hypoxic conditions.However,the underlying mechanisms linking those cellular processes and conditions to disease progression have yet to be defined.Here,we applied a disease similarity approach to identify unknown molecular targets of Alzheimer’s disease by using transcriptomic data from congenital diseases known to increase Alzheimer’s disease risk,namely Down syndrome,Niemann-Pick type C disease,and mucopolysaccharidoses I.We uncovered common pathways,hub genes,and miRNAs across in vitro and in vivo models of these diseases as potential molecular targets for neuroprotection and amelioration of Alzheimer’s disease pathology,many of which have never been associated with Alzheimer’s disease.We then investigated common molecular alterations in brain samples from a Niemann-Pick type C disease mouse model by juxtaposing them with brain samples of both human and mouse models of Alzheimer’s disease.Detailed phenotypic,molecular,chronological,and biological aging analyses revealed that the Npc1tm(I1061T)Dso mouse model can serve as a potential short-lived in vivo model for brain aging and Alzheimer’s disease research.This research represents the first comprehensive approach to congenital disease association with neurodegeneration and a new perspective on Alzheimer’s disease research while highlighting shortcomings and lack of correlation in diverse in vitro models.Considering the lack of an Alzheimer’s disease mouse model that recapitulates the physiological hallmarks of brain aging,the short-lived Npc1^(tm(I1061T)Dso) mouse model can further accelerate the research in these fields and offer a unique model for understanding the molecular mechanisms of Alzheimer’s disease from a perspective of accelerated brain aging. 展开更多
关键词 aging biomarkers Alzheimer’s disease comparative genomics congenital diseases Down syndrome mouse model mucopolysaccharidoses I Niemann-Pick type c disease
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Lipidomic and sterolomic profiles of different brain regions in the mouse model of Alzheimer’s disease
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作者 Xingsen Zhao Liqun Chen +4 位作者 Liangjian Ma Xiaohui Liu Zhongkai Cao Xiangjun Chen Lidan Hu 《Neural Regeneration Research》 2026年第6期2543-2552,共10页
Alzheimer’s disease is the most common cause of dementia.Although increasing evidence suggests that disruptions in lipid metabolism are closely associated with the disease,the overall profile of lipid and sterol chan... Alzheimer’s disease is the most common cause of dementia.Although increasing evidence suggests that disruptions in lipid metabolism are closely associated with the disease,the overall profile of lipid and sterol changes that occur in the brain during Alzheimer’s disease remains unclear.In this study,we compared brain tissues extracted from 32-week-old male wild-type mice and 5×FAD transgenic Alzheimer’s disease model mice,which carry mutations in the amyloid precursor protein(APP)and presenilin 1(PS1)genes.Using untargeted lipidomics and sterolomics techniques,we investigated the metabolic profiles of lipids,with a focus on sterols specifically,in three brain regions:cerebellum,hippocampus,and olfactory bulb.Our results revealed significant alterations in various lipids,particularly in the hippocampus and olfactory bulb,suggesting changes in energy levels in these regions.Further pathway analysis indicated notable disruptions in key metabolic processes,particularly those related to fatty acids and cell membrane components.Additionally,we observed decreased expression of 15 genes involved in lipid and sterol regulation.Collectively,these findings provide new insights into how imbalances in lipid and sterol metabolism may contribute to the progression of Alzheimer’s disease,highlighting potential metabolic pathways involved in the development of this debilitating disease. 展开更多
关键词 Alzheimer’s disease Alzheimer’s disease mouse model brain lipids DYsLIPIDEMIAs lipidomic METABOLIsM neurodegenerative disease sTEROL
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Three-dimensional patient-derived cell models represent an emerging frontier in the study of neurodegenerative diseases
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作者 Rachel J.Boyd Vasiliki Mahairaki 《Neural Regeneration Research》 2026年第6期2327-2328,共2页
Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patien... Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patients,caregivers,and healthcare workers.Alzheimer’s disease(AD)and Parkinson’s disease represent the two most common neurodegenerative disorders in the population,affecting over 65 million people,worldwide. 展开更多
关键词 Alzheimer s disease public health crisis neurodegenerative diseases neurodegenerative disorders parkinson s disease aging three dimensional patient derived cell models
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Optimizing the dengue virus infection mouse model:Comparing different backgrounds and infection route for enhanced stability
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作者 Dan Liao Ming Zhong +7 位作者 Wenjiang Zheng Zhendong Guo Ye Zhou Qiuhong Li Lijuan Qiu Liangwen Yu Haishan Long Geng Li 《Animal Models and Experimental Medicine》 2026年第1期103-114,共12页
Background:In recent decades,the global incidence of dengue fever has been stead-ily increasing,with continuous geographical expansion.Researchers have successfully modeled most clinical symptoms of human dengue fever... Background:In recent decades,the global incidence of dengue fever has been stead-ily increasing,with continuous geographical expansion.Researchers have successfully modeled most clinical symptoms of human dengue fever using interferon type I(IFN-I)or combined IFN-I/II receptor knockout mice infected with dengue virus(DENV).However,this model requires further optimization to better support related studies.Methods:This study aimed to establish a stable dengue infection model by evaluating the effects of different genetic backgrounds and injection routes on DENV infection in interferon receptor knockout mice.We first infected various strains of interferon receptor-deficient mice with DENV and compared their susceptibility based on clini-cal symptoms,viremia levels,organ indices,histopathological findings,and vascular leakage markers.Subsequently,we selected the most susceptible strain to further investigate the impact of different injection methods on infection outcomes.Results:We found that BALB/c background mice with type 1 interferon recep-tor knockout(IFNAR)had the most obvious symptoms.Subsequently,we selected IFNAR−/−BALB/c mice to further explore the effects of different injection methods on dengue virus infection.The results showed that the intraperitoneal injection group had the most severe clinical symptoms,the longest duration of viremia,and the most obvious degree of organ damage.Conclusion:Through systematic screening and optimization,we established a robust animal model of dengue virus infection via intraperitoneal injection in IFNAR−/−BALB/c mice.This model offers a valuable tool for future dengue research. 展开更多
关键词 dengue fever IFNAR−/−BALB/c mice interferon receptor knockout mouse model
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知识图谱驱动的C++课程BOPPPS+ADCD教学模式探索 被引量:1
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作者 王云艳 《计算机教育》 2026年第1期233-239,共7页
针对传统教学中自主学习和迁移学习不足、高阶计算思维培养不足、评价体系动态反馈不足等问题,提出知识图谱驱动的BOPPPS+ADCD线上线下混合教学模式,以C++程序设计课程为例,阐述如何通过知识图谱引领学生自主学习,并在BOPPPS参与式教学... 针对传统教学中自主学习和迁移学习不足、高阶计算思维培养不足、评价体系动态反馈不足等问题,提出知识图谱驱动的BOPPPS+ADCD线上线下混合教学模式,以C++程序设计课程为例,阐述如何通过知识图谱引领学生自主学习,并在BOPPPS参与式教学环节融入ADCD四阶段强化高阶计算思维训练,构建“教学—评价—改进”智慧评价的动态教学闭环以实现教学动态优化,最后说明教学实践效果。 展开更多
关键词 c%PLUs%%PLUs%程序设计 知识图谱 BOPPPs%PLUs%ADcD教学模式 智慧评价
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考虑气热动态特性的P2G-CCS综合能源优化调度
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作者 张涛 王金 +3 位作者 孟衡 刘文丽 司诚真 熊鸣之 《太阳能学报》 北大核心 2026年第1期253-262,共10页
提出考虑气热动态特性的电转气-碳捕集(P2G-CCS)综合能源调度策略。首先,将气热能流特性方程转化至s域,得到二端口传递函数模型,利用卷积定理对其进行Laplace逆变换,从而得到任意时间断面的时域动态模型。其次,在动态模型基础上建立包含... 提出考虑气热动态特性的电转气-碳捕集(P2G-CCS)综合能源调度策略。首先,将气热能流特性方程转化至s域,得到二端口传递函数模型,利用卷积定理对其进行Laplace逆变换,从而得到任意时间断面的时域动态模型。其次,在动态模型基础上建立包含P2G-CCS的IES园区,结合碳交易机制减少碳排放。最后以IEEE-39-20-6为例,建立电-气-热能源系统,通过设置不同调度场景进行对比分析。结果表明,所建动态模型和策略有效提高气热网潮流计算效率的同时,降低碳排放,提高系统调度经济性。 展开更多
关键词 综合能源 P2G-ccs 奖惩阶梯碳交易 气热s域模型
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不同妊娠阶段孕妇蛋白C和蛋白S的变化
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作者 郭帅 宋玉 +6 位作者 陆遥 苗林子 李圆圆 朱梓静 由然 屈晨雪 龚晨 《临床检验杂志》 2026年第2期102-104,共3页
目的观察妊娠不同阶段孕妇蛋白C(PC)和蛋白S(PS)活性的变化特征,并为建立孕妇PC和PS活性参考区间提供依据。方法选取2023年11月至2024年11月就诊于北京大学第一医院的健康孕妇共300例,其中孕早期(≤13周)100例,孕中期(14~27周)100例,孕... 目的观察妊娠不同阶段孕妇蛋白C(PC)和蛋白S(PS)活性的变化特征,并为建立孕妇PC和PS活性参考区间提供依据。方法选取2023年11月至2024年11月就诊于北京大学第一医院的健康孕妇共300例,其中孕早期(≤13周)100例,孕中期(14~27周)100例,孕晚期(≥28周)100例。另选取年龄相匹配的健康非孕女性100例为对照组,检测PC和PS活性并进行统计分析。结果孕中期组和孕晚期组PC活性中位数均高于对照组(Z=-4.465、-3.727,P均<0.01)和孕早期组(Z=-4.681、-3.781,P均<0.01)。孕期PS活性呈递减趋势,孕早期、孕中期、孕晚期与对照组PS活性差异均有统计学意义(Z=-9.505、-12.084、-12.190,P均<0.01)。孕晚期与孕中期、孕早期PS活性差异均有统计学意义(Z=-2.519、-3.399,P均<0.05)。孕早、中、晚期PC活性99%、96%、97%在参考区间内;而PS活性有较高比例低于参考区间下限,孕晚期PC活性93%低于参考区间下限。结论孕期女性PC活性在妊娠中后期略有升高,大多仍处于参考区间内;PS活性妊娠早期即显著下降,持续降低至孕晚期,建议在高危妊娠人群中动态监测PS活性,作为辅助判断高凝风险的指标。 展开更多
关键词 妊娠 蛋白c活性 蛋白s活性 凝血功能
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丹寿汤治疗肾虚血瘀型复发性流产妊娠早期绒毛膜下血肿的效果及对蛋白C、蛋白S水平的影响
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作者 李会娟 徐广立 +4 位作者 张晨雨 郭晶晶 田超 任姝晴 李彦茹 《中国合理用药探索》 2026年第2期134-140,共7页
目的:探讨丹寿汤治疗肾虚血瘀型复发性流产患者妊娠早期绒毛膜下血肿的效果及对蛋白C、蛋白S水平的影响。方法:选取2021年1月~2022年12月就诊于本院生殖医学科门诊的140例肾虚血瘀型复发性流产妊娠早期出现绒毛膜下血肿的患者,按照每例... 目的:探讨丹寿汤治疗肾虚血瘀型复发性流产患者妊娠早期绒毛膜下血肿的效果及对蛋白C、蛋白S水平的影响。方法:选取2021年1月~2022年12月就诊于本院生殖医学科门诊的140例肾虚血瘀型复发性流产妊娠早期出现绒毛膜下血肿的患者,按照每例患者自主意愿选择药物分为对照组和试验组,每组70例。对照组口服地屈孕酮片,试验组给予丹寿汤治疗,两组均持续用药14天。比较两组患者中医证候积分、绒毛膜下血肿面积、子宫动脉血流动力学指标[子宫动脉血流搏动指数(PI)、子宫动脉血流阻力指数(RI)、子宫动脉血流收缩期峰值流速与舒张末期流速的比值(S/D)]、蛋白C、蛋白S水平及临床疗效,并进行安全性评价。结果:治疗后,试验组患者各项中医证候积分及总积分、子宫动脉血流PI、S/D值均低于对照组(P<0.05);绒毛膜下血肿面积小于对照组(P<0.05);蛋白S水平高于对照组(P<0.05);临床治疗总有效率(90.00%)高于对照组(60.00%,P<0.05)。两组患者均未出现胃肠道不适、头晕头痛、皮疹、阴道异常出血、腹痛加重等任何不良反应。结论:丹寿汤对肾虚血瘀型复发性流产妊娠早期出现绒毛膜下血肿患者疗效较佳,可有效促进绒毛膜下血肿吸收,改善子宫动脉血流指标。其作用机制可能与调节患者体内凝血-纤溶系统平衡有关,进而影响绒毛膜下血肿的吸收。 展开更多
关键词 丹寿汤 绒毛膜下血肿 中医证候 蛋白c 蛋白s
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Ta-C涂层刀具钻削Al-50wt%Si合金的钻削力预测模型研究
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作者 邹继胤 金成哲 +1 位作者 周浩淳 刘玮 《工具技术》 北大核心 2026年第1期70-77,共8页
Al-50wt%Si合金具有低热膨胀系数、高硬度、优异耐磨性和轻量化特性,也因高硅铝含量导致其存在加工难题,通过物理气相沉积(PVD)技术在硬质合金麻花钻表面制备Ta-C涂层。采用正交试验和单因素试验法,对Al-50wt%Si合金进行钻削试验,探究... Al-50wt%Si合金具有低热膨胀系数、高硬度、优异耐磨性和轻量化特性,也因高硅铝含量导致其存在加工难题,通过物理气相沉积(PVD)技术在硬质合金麻花钻表面制备Ta-C涂层。采用正交试验和单因素试验法,对Al-50wt%Si合金进行钻削试验,探究钻头直径d、主轴转速n和进给量f对钻削力的影响规律。结果表明:Ta-C涂层凭借其高硬度和低摩擦系数,显著降低钻削轴向力和扭矩;轴向力与扭矩随钻头直径与进给量的增大呈线性增长,而随主轴转速升高呈现先降后增的趋势。通过多元线性回归分析,建立Ta-C涂层钻削力预测模型,其预测平均误差为4.85%,且方差分析表明模型具有高度显著性,为实现Al-50wt%Si合金的高效、低成本加工提供理论支撑与工艺优化参考。 展开更多
关键词 Ta-c涂层 Al-50wt%si合金 钻削力 预测模型
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S55C钢工件厚度对激光表面淬火组织与性能的影响
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作者 李琦 王博 +4 位作者 程战 王生希 朱挺 李日榜 赵凯鹏 《金属热处理》 北大核心 2026年第1期302-309,共8页
采用恒定激光参数(功率750 W、扫描速度7.5 mm/s)对不同厚度(h=2.5~15.0 mm)的S55C钢件进行激光表面淬火处理,并结合数值模拟,研究了厚度对该钢组织、硬度和耐磨性的影响。结果表明,所有试样淬硬层均由马氏体与残留奥氏体构成,当厚度h&l... 采用恒定激光参数(功率750 W、扫描速度7.5 mm/s)对不同厚度(h=2.5~15.0 mm)的S55C钢件进行激光表面淬火处理,并结合数值模拟,研究了厚度对该钢组织、硬度和耐磨性的影响。结果表明,所有试样淬硬层均由马氏体与残留奥氏体构成,当厚度h<7.5 mm时,组织中还存在屈氏体;当h≥7.5 mm时,马氏体组织更细小,残留奥氏体含量降低。在2.5~7.5 mm厚度范围内,显微硬度随厚度的增加而快速增大,当h=7.5 mm时硬度最大,达到780 HV0.5,之后随厚度的进一步增大,硬度基本不变。淬火深度(硬度>600 HV0.5)也随厚度增加而增加,当h≥7.5 mm时,淬火深度变化不大,基本为0.5 mm。模拟试验分析认为,当冷却速率≥2.1×10^(3)℃/s时,可获得高硬度(≥600 HV0.5)的细密马氏体组织,满足导轨淬火要求。摩擦磨损试验表明,随着试样厚度增加,平均摩擦因数与磨损量总体下降,磨损机制由磨粒磨损、黏着磨损、疲劳磨损和氧化磨损共同作用,逐渐转变为以磨粒磨损和氧化磨损为主。 展开更多
关键词 s55c 激光淬火 工件厚度 显微组织 硬度 耐磨性
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不同类型子痫前期患者血浆蛋白S、蛋白C和抗凝血酶Ⅲ活性表达及妊娠结局
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作者 王玉锋 《河南医学研究》 2026年第1期80-83,共4页
目的探讨不同类型子痫前期(PE)患者血浆蛋白S、蛋白C、抗凝血酶Ⅲ活性表达,并分析不同类型PE患者妊娠结局。方法回顾性收集郑州市妇幼保健院2020年1月至2023年11月收治的50例早发型子痫前期(EOPE)孕妇病历资料归入EOPE组,另收集医院同... 目的探讨不同类型子痫前期(PE)患者血浆蛋白S、蛋白C、抗凝血酶Ⅲ活性表达,并分析不同类型PE患者妊娠结局。方法回顾性收集郑州市妇幼保健院2020年1月至2023年11月收治的50例早发型子痫前期(EOPE)孕妇病历资料归入EOPE组,另收集医院同期收治的50例晚发型子痫前期(LOPE)孕妇病历资料归入LOPE组。另选择医院同期收治的50例孕周<34周的健康孕妇产检资料作为对照1组,50例孕周≥34周的健康孕妇产检资料作为对照2组。对比4组基线资料、血浆蛋白S、蛋白C、抗凝血酶Ⅲ活性表达及PE患者不良妊娠结局发生情况。结果EOPE组与LOPE组血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性对比,差异无统计学意义(P>0.05)。EOPE组血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性低于对照1组(P<0.05)。LOPE组血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性低于对照2组(P<0.05)。对照1组和对照2组血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性对比,差异无统计学意义(P>0.05)。经统计,LOPE组发生不良妊娠结局11例(22.00%),EOPE组发生不良妊娠结局21例(42.00%)。两组不良妊娠结局发生率差异有统计学意义(χ^(2)=4.596,P=0.032)。通过logistic回归分析结果显示,血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性表达会影响EOPE不良妊娠结局发生(P<0.05)。结论血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性降低与PE发病有关。EOPE患者发生不良妊娠结局概率较LOPE患者高。血浆蛋白S、蛋白C及抗凝血酶Ⅲ活性降低可影响EOPE患者不良妊娠结局发生。 展开更多
关键词 子痫前期 血浆蛋白s 血浆蛋白c 抗凝血酶Ⅲ
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负弯矩区钢-SFRC组合桥面板静力与疲劳性能试验研究
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作者 吴亚坤 傅晨曦 +2 位作者 苏强 苏庆田 程震宇 《桥梁建设》 北大核心 2026年第1期66-73,共8页
为研究负弯矩区钢-钢纤维混凝土(Steel Fiber Reinforced Concrete,SFRC)组合桥面板的静力与疲劳性能,以某高速公路跨线连续钢箱梁桥钢-SFRC组合桥面板为背景,设计制作2个钢-SFRC组合桥面板试件和1个钢桥面板试件,通过静力试验研究2种... 为研究负弯矩区钢-钢纤维混凝土(Steel Fiber Reinforced Concrete,SFRC)组合桥面板的静力与疲劳性能,以某高速公路跨线连续钢箱梁桥钢-SFRC组合桥面板为背景,设计制作2个钢-SFRC组合桥面板试件和1个钢桥面板试件,通过静力试验研究2种桥面板的抗负弯性能和破坏形态,通过疲劳试验研究钢-SFRC组合桥面板的疲劳性能和疲劳失效模式。结果表明:钢-SFRC组合桥面板的屈服强度较钢桥面板提升45.4%,极限承载力提升9.4%;SFRC结构层的名义开裂强度为8.56 MPa,开裂后对结构整体刚度影响较小;SFRC结构层可显著提升钢桥面板易损细节的疲劳性能,钢桥面板在设计服役期常幅疲劳荷载和超服役期变幅疲劳荷载作用下均未产生疲劳裂纹,钢顶板厚度可优化至12 mm;钢-SFRC组合桥面板的疲劳性能由SFRC结构层决定,以0.2 mm作为SFRC结构层的临界裂缝宽度,建立的S0.2~N0.2曲线可用于钢-SFRC组合桥面板中SFRC结构层的疲劳性能评估,试验结束时,构件SFRC结构层未达到疲劳破坏标准,设计中厚度宜取80~120 mm。 展开更多
关键词 组合桥面板 钢纤维混凝土 负弯矩区 静力性能 疲劳性能 s~N曲线 模型试验
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Environmental controls over calcium and magnesium concentrations in the forest floor and topsoil in the Loess Plateau,China
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作者 Feng Xue Ning Pan +9 位作者 Hongkun Cui Aolin Li Mingfei Zhao Kaixiong Xing Yuhang Wang Xuejuan Bai Can Wang Zhijun Yu Jingze Liu Muyi Kang 《Journal of Forestry Research》 2026年第2期201-212,共12页
The dynamics of calcium(Ca)and magnesium(Mg)in the forest floor and topsoil caused by anthropogenic and natural processes continue to be a concern in temperate forests.However,the impacts of abiotic and biotic variabl... The dynamics of calcium(Ca)and magnesium(Mg)in the forest floor and topsoil caused by anthropogenic and natural processes continue to be a concern in temperate forests.However,the impacts of abiotic and biotic variables as well as their interactions remain unclear,especially in areas undergoing long-term forest restoration.In this study,Ca and Mg concentrations in the forest floor and topsoil from 239 forest plots across the Loess Plateau were measured,and the effects of forest types,climate,soil properties,stand characteristics and nitrogen deposition were explored.The results showed significantly higher Ca concentrations in the forest floor(20.68±8.04 mg/g)than in the topsoil(13.28±12.83 mg/g),whereas Mg exhibited the inverse pattern(3.64±1.09 and 10.11±2.51 mg/g,respectively).The effect of forest types was only significant on forest floor Ca,and Ca concentrations were higher in broadleaf and mixed forests than in coniferous forests.Overall,Ca and Mg concentrations in forest floor and topsoil increased with latitudes while decreased with elevations,and the significance of the trends varied among forest types.Forest floor Ca and Mg were mainly influenced by environmental variables aboveground,i.e.,basal area(BA)and mean annual precipitation(MAP),respectively;topsoil Ca and Mg were more affected by soil properties(soil C/N and pH,respectively).Those suggested a depletion of Ca belowground was associated with forest growth and enriched soil nitrogen,and the leaching of mobile Mg was correlated with rainfall and soil acidification.Besides,the impact of environmental variables on Ca-Mg balance(Ca/Mg ratio)belowground was primarily through the regulation of Ca.Elucidating the influence of environmental variables will improve our ability to predict future changes in base cations and thus forest soil health in the greening vegetated Loess Plateau. 展开更多
关键词 soil c/N Basal area Random-forest model Temperate forests Base cations ELEVATION
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Physics-informed machine learning for identifying gradient-distributed plastic parameters of the S38C axle by nano-indentation
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作者 Siyu Li Lvfeng Jiang +4 位作者 Yanan Hu Jian Li Xu Zhang Qianhua Kan Guozheng Kang 《Acta Mechanica Sinica》 2026年第1期105-121,共17页
The S38C railway axle undergoes induction hardening,resulting in a gradient-distributed microstructure and mechanical properties.The accurate identification of gradient-distributed plastic parameters for the S38C axle... The S38C railway axle undergoes induction hardening,resulting in a gradient-distributed microstructure and mechanical properties.The accurate identification of gradient-distributed plastic parameters for the S38C axle remains a challenging task.To tackle this challenge,the present study proposes a novel approach for identifying the gradient-distributed plastic parameters for the S38C axle by integrating nano-indentation techniques with the machine learning method.Firstly,nano-indentation tests are conducted along the radial direction of the S38C axle to obtain the gradient-distributed load-displacement curves,nano-hardness,and elastic modulus.Subsequently,the dimensionless analysis is performed to obtain the representative stress,strain,and yield stress from load-displacement curves.These parameters are then incorporated into the machine learning method as physical information to identify the gradient-distributed plastic parameters of the S38C axle.The results indicate that the proposed method based on the physics-informed neural network and multi-fidelity neural network successfully identifies the gradient-distributed plastic parameters of the S38C axles and demonstrates superior prediction accuracy and generalization compared with the purely data-driven machine learning method. 展开更多
关键词 s38c axle Nanoindentation Physics-informed machine learning Gradient structure Plastic parameters
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不同钙硅比纳米C-S-H对水泥早期水化性能的影响
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作者 孔靖勋 房延凤 +2 位作者 宋承哲 张丽敏 郭金波 《混凝土》 北大核心 2026年第1期106-110,120,共6页
纳米C-S-H作为一种新型的早强剂,对于有早强要求的混凝土工程具有重要意义。钙硅摩尔比(C/S)的变化会影响纳米C-S-H的结构及其水泥水化,其具体影响规律尚存争议。通过共沉淀法合成了不同C/S的纳米C-S-H悬浮液,通过凝结时间测试、力学性... 纳米C-S-H作为一种新型的早强剂,对于有早强要求的混凝土工程具有重要意义。钙硅摩尔比(C/S)的变化会影响纳米C-S-H的结构及其水泥水化,其具体影响规律尚存争议。通过共沉淀法合成了不同C/S的纳米C-S-H悬浮液,通过凝结时间测试、力学性能测试、QXRD、TG及SEM等分析方法研究不同C/S对纳米C-S-H的粒径大小、以及对水泥水化进程和水化产物的影响规律以及作用机理。随着C/S的增加,纳米C-S-H对水泥早期水化程度的影响呈现先增强后减弱的趋势,显著促进了水化放热速率使得水泥水化的第二放热峰提前出现。当C/S为1.2时,其早强作用效果最优,其中水泥初凝时间缩短27.3%,终凝时间缩短35.1%。通过XRD Rietveld定量计算结果可知,纳米C-S-H可有效加快水泥的水化进程,提供更多的成核位点从而促进了C3S水化产物C-S-H凝胶的生成,使得水泥浆体的早期抗压强度较空白组提高了57.4%。纳米C-S-H主要在水泥水化早期阶段发挥作用,随着时间的推移,其对强度随时间增长提升效果逐渐减弱。 展开更多
关键词 纳米c-s-H 钙硅比 早期水化 早期强度 Rietveld定量计算
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基于CT参数构建Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的研究
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作者 杨宇琦 王思聪 +2 位作者 卢礼卿 张春芳 程远大 《中国临床新医学》 2026年第2期214-219,共6页
目的 探讨基于CT参数建立的Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的价值。方法 回顾性收集2015年1月至2025年6月在中南大学湘雅医院胸外科经手术切除后病理检查证实为前纵隔囊肿(含胸腺囊肿和支气管囊肿)或胸腺瘤患者的... 目的 探讨基于CT参数建立的Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的价值。方法 回顾性收集2015年1月至2025年6月在中南大学湘雅医院胸外科经手术切除后病理检查证实为前纵隔囊肿(含胸腺囊肿和支气管囊肿)或胸腺瘤患者的临床病理资料,计算肿瘤平扫和增强CT值与主动脉CT值的比值,采用单因素方差分析结合Bonferroni校正进行组间比较,基于筛得CT参数建立Fisher判别函数并对其进行验证。结果 共236例患者纳入研究,其中胸腺瘤组159例、胸腺囊肿组54例、支气管囊肿组23例。三组年龄比较差异无统计学意义(P > 0.05)。与胸腺瘤组和胸腺囊肿组相比,支气管囊肿组患者女性人数比例更高(P<0.001),肿瘤最大径更小(P<0.001)。胸腺瘤组中肿瘤呈分叶状的占比显著高于胸腺囊肿组和支气管囊肿组(P<0.001),脂肪间隙清晰率显著低于胸腺囊肿组和支气管囊肿组(P<0.001)。胸腺瘤组和支气管囊肿组的平扫CT值、平扫主动脉CT比值、增强CT值及增强主动脉CT比值均显著高于胸腺囊肿组(P<0.001),其中支气管囊肿组增强CT值、增强主动脉CT比值显著低于胸腺瘤组(P<0.001)。胸腺囊肿组和支气管囊肿组的CT强化值显著低于胸腺瘤组(P<0.001)。构建Fisher判别函数:D1=0.245×性别(0=女性,1=男性)+0.782×肿瘤形状(1=无分叶状,2=分叶状)+0.644×脂肪间隙(0=模糊,1=清晰)-0.344×增强CT值+97.228×增强主动脉CT比值+0.059×CT强化值-9.357;D2=0.970×性别(0=女性,1=男性)+0.583×肿瘤形状(1=无分叶状,2=分叶状)+0.903×脂肪间隙(0=模糊,1=清晰)-0.094×增强CT值+4.749×增强主动脉CT比值+0.110×CT强化值+0.546。交叉验证结果显示,该模型鉴别诊断胸腺瘤与前纵隔囊肿的总体符合率为95.76%。结论 基于CT参数建立的判别函数诊断模型在鉴别胸腺瘤与前纵隔囊肿中具有较高的诊断价值。 展开更多
关键词 胸腺瘤 前纵隔囊肿 胸腺囊肿 支气管囊肿 cT值 鉴别诊断 Fisher判别函数模型
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NAD推出Classic系列两款立体声合并式功放C3030和C3030S
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《视听前线》 2026年第2期63-63,共1页
NAD正式发布两款全新立体声合并式功放——NADC3030与NADC3030S。新品的设计灵感源于NAD品牌经典复古机型,同时承袭了周年纪念版功放NADC3050的全球热销基因,既延续了品牌对前瞻设计的执着追求,又实现了复古美学与现代高保真音质、多元... NAD正式发布两款全新立体声合并式功放——NADC3030与NADC3030S。新品的设计灵感源于NAD品牌经典复古机型,同时承袭了周年纪念版功放NADC3050的全球热销基因,既延续了品牌对前瞻设计的执着追求,又实现了复古美学与现代高保真音质、多元连接功能的完美融合。 展开更多
关键词 c3030s classic系列 复古美学 立体声合并式功放
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基于血清SAA/CRP、RBP水平的难治性肺炎支原体肺炎患儿不良预后预测模型构建
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作者 常甄瑱 高婉卿 +2 位作者 童仁香 陈倩 柳娜娜 《山东医药》 2026年第1期74-78,共5页
目的基于血清淀粉样蛋白A/C反应蛋白(SAA/CRP)、视黄醇结合蛋白(RBP)水平构建难治性肺炎支原体肺炎(RMPP)患儿不良预后的预测模型。方法选取收治的RMPP患儿198例,检测其血清SAA、CRP和RBP水平,并计算SAA/CRP,根据入院后28 d预后将RMPP... 目的基于血清淀粉样蛋白A/C反应蛋白(SAA/CRP)、视黄醇结合蛋白(RBP)水平构建难治性肺炎支原体肺炎(RMPP)患儿不良预后的预测模型。方法选取收治的RMPP患儿198例,检测其血清SAA、CRP和RBP水平,并计算SAA/CRP,根据入院后28 d预后将RMPP患儿分为不良预后和良好预后,并收集患儿相关临床资料。采用多因素Logistic回归分析不良预后的影响因素并构建预测模型,采用ROC曲线分析各指标及预测模型对RMPP患儿不良预后的预测价值,采用Bootstrap自助法进行内部验证。结果入院28 d后,198例RMPP患儿不良预后发生率为30.30%(60/198)。不良预后患儿较良好预后患儿重症比例高,热程和氧疗时间长,血清SAA/CRP高,RBP水平低(P均<0.05)。多因素回归分析显示,热程、重症RMPP、氧疗时间长、血清SAA/CRP高为RMPP患儿不良预后的独立危险因素,RBP水平高为独立保护因素(P均<0.05)。根据独立影响因素构建预测模型,回归方程为Logit(P)=-10.707+0.347×热程+1.811×病情程度+0.765×氧疗时间+1.085×SAA/CRP-0.258×RBP,曲线下面积为0.920,高于热程、病情程度、氧疗时间、SAA/CRP、RBP单独预测的0.674、0.696、0.682、0.755、0.747(P均<0.05)。Hosmer-Lemeshow检验显示χ^(2)=6.320,P=0.611,模型拟合良好。经1000次Bootstrap自助法进行内部验证,预测模型的C指数为0.920,区分度、稳定性较高。结论血清SAA/CRP水平升高和RBP水平降低与RMPP患儿不良预后相关,基于此构建的预测模型对其有较高的预测效能。 展开更多
关键词 难治性肺炎支原体肺炎 血清淀粉样蛋白A c反应蛋白 视黄醇结合蛋白 预测模型
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Six promising drug repurposing candidates for Alzheimer's disease and their sex-specific mechanisms and efficacy
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作者 Maria E.Figueiredo-Pereira Peter A.Serrano Patricia Rockwell 《Neural Regeneration Research》 2026年第7期2882-2888,共7页
Alzheimer s disease is a neurodegenerative disorder that leads to progressive memory loss,cognitive decline,and behavioral changes.Des pite ongoing research,its exa ct causes and effective treatments remain elusive.Tr... Alzheimer s disease is a neurodegenerative disorder that leads to progressive memory loss,cognitive decline,and behavioral changes.Des pite ongoing research,its exa ct causes and effective treatments remain elusive.Traditional approaches have focused on symptom management,but breakthroughs in bioinformatics and high-thro ughput drug screening are offering new pathways to potential therapies.This review highlights our recent effo rts to identify novel drug candidates for Alzheimer's disease by leve raging computational methods and la rge-scale biological datasets.Our work introduces two key innovations in Alzheimer's disease research:addressing sex-specific diffe rences and leve raging drug repurposing for accelerated treatment discove ry.By combining sex-stratified preclinical data with machine learning and in vivo validation,we improve translational relevance and support precision medicine.Using the TgF344-AD rat model,which mimics human Alzheimer's disease spatial memory deficits and pathology,we explored the efficacy of various US Food and Drug Administrationapproved and investigational drugs.These included ibudilast,timapiprant,RG2833,diazoxide/dibenzoylmethane(combined),and BT-11,which targeted key Alzheimer's disease-related molecular pathways such as amyloid-beta plaques,Ta u tangles,and neuroinflammation.These drugs,at various stages of development,offer hope for not only managing symptoms but also addressing the underlying mechanisms of Alzheimer's disease.This review underscores the need for a multifaceted approach to Alzheimer's disease treatment,combining symptom relief with disease modification. 展开更多
关键词 Alzheimer’s disease BT-11 DIAZOXIDE DIBENZOYLMETHANE drug repurposing high-throughput drug approach IBUDILAsT RG2833 TgF344-AD rat model timapiprant
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