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关于Euler gamma函数Γ与一类L-函数的代数微分无关性
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作者 李效敏 李奕萱 《中国海洋大学学报(自然科学版)》 北大核心 2025年第S1期106-109,148,共5页
本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了... 本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了陈玮和王琼2021年的相应结果。 展开更多
关键词 Euler gamma函数Γ L-函数类S 微分无关性 代数微分方程
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Gamma算子收敛速度的估计
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作者 郑雪静 王平华 《商丘师范学院学报》 2025年第6期21-24,共4页
进一步研究了Gamma算子G_(n)(f,x)的逼近性质.利用概率型算子基函数的概率性质,通过估计相关函数关于Gamma分布的数学期望,分别导出Gamma算子的关于局部有界函数以及绝对连续函数收敛速度的新的系数估计.
关键词 gamma算子 数学期望 收敛速度 估计
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Gamma 3 U-Blade系统治疗老年骨质疏松性股骨转子间骨折的早期疗效 被引量:2
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作者 范文斌 石柳 +4 位作者 谢添 张程 陈翔溆 陈辉 芮云峰 《中国修复重建外科杂志》 北大核心 2025年第1期47-52,共6页
目的与Gamma 3髓内钉比较,探讨Gamma 3 U-Blade系统治疗老年骨质疏松性股骨转子间骨折的早期疗效。方法回顾性分析2020年2月—2023年2月收治且符合选择标准的124例老年骨质疏松性股骨转子间骨折患者临床资料,内固定术中采用普通Gamma 3... 目的与Gamma 3髓内钉比较,探讨Gamma 3 U-Blade系统治疗老年骨质疏松性股骨转子间骨折的早期疗效。方法回顾性分析2020年2月—2023年2月收治且符合选择标准的124例老年骨质疏松性股骨转子间骨折患者临床资料,内固定术中采用普通Gamma 3髓内钉65例(对照组)、Gamma 3 U-Blade系统59例(UB组)。两组患者年龄、性别、身体质量指数、美国麻醉医师协会(ASA)分级、骨密度、受伤至手术时间以及骨折分型、侧别等基线资料比较,差异均无统计学意义(P>0.05),具有可比性。比较两组手术时间、术中出血量、住院时间、骨折愈合时间,术后即刻尖顶距、骨折复位质量、拉力螺钉位置,末次随访时拉力螺钉滑动距离、颈干角变化值,术后12个月髋关节Harris评分,以及内固定相关并发症发生情况。结果UB组手术时间、术中出血量及住院时间较对照组略增加,但差异无统计学意义(P>0.05)。两组患者均获随访,随访时间12~24个月,平均17.1个月。术后12个月,两组髋关节Harris评分差异均无统计学意义(P<0.05)。影像学复查示,两组尖顶距、骨折复位质量、拉力螺钉位置组间差异均无统计学意义(P>0.05);骨折均顺利愈合,且愈合时间差异亦无统计学意义(P>0.05)。末次随访时,UB组颈干角变化值、拉力螺钉滑动距离均小于对照组,差异有统计学意义(P<0.05)。随访期间,UB组无内固定相关并发症发生,对照组6例(9.2%)发生并发症,发生率组间差异有统计学意义(P<0.05)。结论使用Gamma 3 U-Blade系统治疗老年骨质疏松性股骨转子间骨折可以获得良好早期疗效,影像学结果优于普通Gamma 3髓内钉。 展开更多
关键词 股骨转子间骨折 gamma 3 U-Blade系统 髓内钉 内固定 骨质疏松 老年人
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基于广义Gamma模型的完整雨滴谱分布拟合方法
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作者 赵欣 王改利 +2 位作者 文镓齐 李冉 郭在华 《应用气象学报》 北大核心 2025年第3期328-338,共11页
基于2021年4月4日、9月13日、9月29日西藏墨脱和2022年5月10日、6月9日、6月10日广东龙门的微雨雷达与降水现象仪联合观测数据,构建完整雨滴谱分布。利用广义Gamma模型拟合完整雨滴谱分布,并与标准Gamma模型拟合结果进行对比。结果表明... 基于2021年4月4日、9月13日、9月29日西藏墨脱和2022年5月10日、6月9日、6月10日广东龙门的微雨雷达与降水现象仪联合观测数据,构建完整雨滴谱分布。利用广义Gamma模型拟合完整雨滴谱分布,并与标准Gamma模型拟合结果进行对比。结果表明:完整雨滴谱数据计算的降水率更接近地面雨量计观测的降水率,相关性更高、偏差更小;采用雨滴谱分布的双矩(第3矩和第6矩)归一化,可以实现包含两个形状参数(μ和c)的广义Gamma模型拟合,且拟合的完整雨滴谱分布与观测更接近,可以同时描述毛毛雨模式、降水模式以及两者间的区域。定量对比结果显示,广义Gamma模型拟合比标准Gamma模型拟合的偏差更小、模型效率系数更高;墨脱和龙门不同微物理过程降水(直径影响型和数量影响型)的双矩归一化雨滴谱形状一致性很好,特别是在归一化直径范围的中心部分,这种相对稳定性对于应用广义Gamma模型从双偏振天气雷达数据反演雨滴谱分布具有重要的应用价值。 展开更多
关键词 微雨雷达 降水现象仪 雨滴谱分布 广义gamma模型 双矩归一化
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求解多模概率分布Gamma混合模型的半EM算法
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作者 陈佳琪 何玉林 +1 位作者 成英超 黄哲学 《计算机应用》 北大核心 2025年第7期2153-2161,共9页
期望最大化(EM)算法在混合模型参数估计中发挥着重要作用,然而现有的EM算法在求解Gamma混合模型(GaMM)参数时存在局限性,主要体现在因近似计算导致的低质量参数估计,以及由于大量数值计算造成的计算效率低下问题。为了克服这些局限,并... 期望最大化(EM)算法在混合模型参数估计中发挥着重要作用,然而现有的EM算法在求解Gamma混合模型(GaMM)参数时存在局限性,主要体现在因近似计算导致的低质量参数估计,以及由于大量数值计算造成的计算效率低下问题。为了克服这些局限,并充分利用数据的多模性质,提出一种半EM(Semi-EM)算法求解用于估计多模概率分布的GaMM。首先,通过聚类探测数据的空间分布特性,以初始化GaMM参数,进而更准确地刻画数据的多模性;其次,在EM算法框架的基础上,对于缺乏封闭更新表达式而导致的参数更新困难问题,采用自定义的启发式策略对GaMM形状参数进行更新,使它们朝着最大化对数似然值的方向逐步调整,同时以封闭形式更新其他参数。经过一系列具有说服力的实验,验证了Semi-EM算法的可行性、合理性和有效性。实验结果表明,Semi-EM算法在精确估计多模概率分布方面优于对比的4种算法,具有更低的误差指标以及更高的对数似然值,表明该算法能提供更准确的模型参数估计,从而更精确地刻画数据的多模性质。 展开更多
关键词 多模概率密度函数 gamma混合模型 期望最大化算法 聚类 对数似然函数
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基于Gamma和时变Markov模型的管道寿命预测
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作者 何莹 董增寿 郑宇佳 《太原科技大学学报》 2025年第2期139-144,151,共7页
由于埋地天然气管道在复杂的运行环境下其退化状态具有动态转移性,为避免天然气管道泄漏导致安全事故发生,提出一种基于Gamma和时变Markov模型的管道剩余寿命预测方法。首先采用连续随机过程Gamma描述管道腐蚀退化过程;其次将连续随机... 由于埋地天然气管道在复杂的运行环境下其退化状态具有动态转移性,为避免天然气管道泄漏导致安全事故发生,提出一种基于Gamma和时变Markov模型的管道剩余寿命预测方法。首先采用连续随机过程Gamma描述管道腐蚀退化过程;其次将连续随机过程划分状态空间后利用Markov理论建立剩余寿命预测模型;为适应天然气管道的实际退化过程,引入时变转移概率矩阵解决了转移概率固定的问题;最后通过实例验证并在MATLAB中仿真,将仿真拟合值与实际值对比。结果表明:基于Gamma和时变Markov结合模型的方法预测精度高,预测值比实际寿命小,更好地保障了天然气管道的安全运行。 展开更多
关键词 剩余寿命预测 状态空间划分 时变性 gamma MARKOV 转移概率矩阵
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逐步Ⅱ型删失数据下Gamma分布的参数推断
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作者 王子豪 郭照庄 《新乡学院学报》 2025年第3期10-13,共4页
基于逐步Ⅱ型删失方案研究了Gamma分布的参数估计问题,为了克服该删失方案下求解Gamma分布的对数似然函数存在的困难,利用EM算法进行了参数的极大似然估计,利用Bootstrap自助法进行了参数的区间估计,利用Monte-Carlo方法对逐步Ⅱ型删失... 基于逐步Ⅱ型删失方案研究了Gamma分布的参数估计问题,为了克服该删失方案下求解Gamma分布的对数似然函数存在的困难,利用EM算法进行了参数的极大似然估计,利用Bootstrap自助法进行了参数的区间估计,利用Monte-Carlo方法对逐步Ⅱ型删失试验下的参数估计进行模拟。结果表明,随着样本量的增大,参数估计值的平均偏差和均方误差均逐渐减小,区间长度也逐渐变短,利用EM算法对删失数据下Gamma分布进行参数估计是一种有效的方法。 展开更多
关键词 gamma分布 逐步Ⅱ型删失 EM算法 Bootstrap区间估计
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融合自适应Gamma校正与YOLOv5的夜间驾驶辅助系统设计
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作者 李昊锟 宫福成 王立东 《电子产品世界》 2025年第4期1-4,8,共5页
光照条件差会对夜间行车安全构成严峻挑战。基于此,设计了一种融合自适应Gamma校正与YOLOv5的夜间驾驶辅助系统。该系统通过树莓派控制核心及多个外设,实现图像采集、图像增强、目标检测和语音提示等功能,从而有效降低驾驶风险。介绍了... 光照条件差会对夜间行车安全构成严峻挑战。基于此,设计了一种融合自适应Gamma校正与YOLOv5的夜间驾驶辅助系统。该系统通过树莓派控制核心及多个外设,实现图像采集、图像增强、目标检测和语音提示等功能,从而有效降低驾驶风险。介绍了系统硬件组成及功能,阐述了软件自适应Gamma校正的实现过程和YOLOv5目标检测模型的训练过程,并在实验环节验证了系统的可靠性。 展开更多
关键词 夜间驾驶 目标检测 自适应gamma校正 YOLOv5
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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Axion Gamma-Ray Signatures from Quark Matter in Neutron Stars and Gravitational Wave Comparisons
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作者 Bijan Berenji 《Journal of Modern Physics》 2025年第1期152-166,共15页
We present a theoretical model for detecting axions from neutron stars in a QCD phase of quark matter. The axions would be produced from a quark-antiquark pair uu¯or dd¯, in loop(s) involving gluons. The chi... We present a theoretical model for detecting axions from neutron stars in a QCD phase of quark matter. The axions would be produced from a quark-antiquark pair uu¯or dd¯, in loop(s) involving gluons. The chiral anomaly of QCD and the spontaneously broken symmetry are invoked to explain the non-conservation of the axion current. From the coupling form factors, the axion emissivities ϵacan be derived, from which fluxes can be determined. We predict a photon flux, which may be detectable by Fermi LAT, and limits on the QCD mass ma. In this model, axions decay to gamma rays in a 2-photon vertex. We may determine the expected fluxes from the theoretical emissivity. The sensitivity curve from the Fermi Large Area Telescope (Fermi LAT) would allow axion mass constraints for neutron stars as low as ma≤10−14eV 95% C.L. Axions could thus be detectable in gamma rays for neutron stars as distant as 100 kpc. A signal from LIGO GWS 170817 could be placed from the NS-NS merger, which gives an upper limit of ma≤10−10eV. 展开更多
关键词 Astrophysics PHENOMENOLOGY QCD Axion Neutron Stars Nuclear Theory gamma Rays Gravitational Waves Fermi-LAT
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基于数据分析的GAMMA自动调试系统
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作者 何胜斌 潘云龙 何祥祺 《西安文理学院学报(自然科学版)》 2025年第1期27-31,50,共6页
智能显示终端在人们生活中广泛使用,已经息息相关,带来更多的视觉体验.经过详细调校的优秀产品出厂时应该保证所有设计指标,克服个体差异性.众多参数单纯靠人力调节,操作繁琐,调试时间久,无法满足日益增长的产线产能.通过系统分析图像... 智能显示终端在人们生活中广泛使用,已经息息相关,带来更多的视觉体验.经过详细调校的优秀产品出厂时应该保证所有设计指标,克服个体差异性.众多参数单纯靠人力调节,操作繁琐,调试时间久,无法满足日益增长的产线产能.通过系统分析图像显示曲线,提出逼近式数据采集形成Auto Gamma数据库和改进的传输协议,可以精确模拟用户操作行为,提高生产效率,减少测试人为错误,并且提供完整的透明性,可追溯性. 展开更多
关键词 显示终端 调校 Auto gamma 追溯
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Coordinated improvement of maize grain yield and protein quality by the ZmMADS8-ZmMADS47-O2 module and a G protein gamma subunit
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作者 Yunfu Li Qiang Ning +9 位作者 Ran Zhao Dan Liu Nan Li Qing Xiong Qin Sun Yanfang Du Ruijie Mao Jimin Zhan Zuxin Zhang Lei Liu 《The Crop Journal》 2025年第3期805-817,共13页
Improving protein quality and grain yield traits coordinately is an important goal for crop breeding.To date,many protein-quality or grain-yield regulation genes have been identified.However,the genetic strategies int... Improving protein quality and grain yield traits coordinately is an important goal for crop breeding.To date,many protein-quality or grain-yield regulation genes have been identified.However,the genetic strategies integrating these genes in good-protein-quality and high-yield crop breeding practice are far from established.Here,we characterized the functions of the MADS domain-containing protein Zm MADS8 and Zea mays G protein gamma subunit 1(Zm GG1)in regulating protein quality and grain yield of maize.Zm MADS8 positively regulates zein protein accumulation and negatively regulates nonzein protein and lysine levels in kernels by interacting with Zm MADS47 to promote the transcriptional activation of Opaque2.Additionally,Zm MADS8 regulates starch content of kernels by targeting genes involved in starch biosynthesis.Zm GG1,a putative interactor of Zm MADS8,negatively regulates kernel number with a trade-off effect on kernel starch accumulation.The mads8;zmgg1 double mutant improved protein quality by attenuating zein biosynthesis and increasing essential lysine level,and increased grain yield by increasing kernel number,compensating for decreased starch biosynthesis.Our findings revealed the biological function of Zm MADS8 and Zm GG1 in regulating protein quality and yield related traits and suggested a genetic strategy by direct editing of Zm MADS8 and Zm GG1 to improve grain yield and protein quality simultaneously. 展开更多
关键词 ZEIN Starch MADS-box protein G protein gamma subunit Kernel number
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基于全场Gamma系数的相位误差校正
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作者 亓广宇 《信息系统工程》 2025年第1期62-65,共4页
面结构光由于可无接触对物体进行高质量的三维重建,目前已被广泛地应用在工业、医疗、文物保护等领域。工业领域中目前多以多频外差和格雷码+四步相移的编码结构光作为解决方案。采用单目多频外差方法,DLP的Gamma效应则会导致解算出的... 面结构光由于可无接触对物体进行高质量的三维重建,目前已被广泛地应用在工业、医疗、文物保护等领域。工业领域中目前多以多频外差和格雷码+四步相移的编码结构光作为解决方案。采用单目多频外差方法,DLP的Gamma效应则会导致解算出的点云产生周期性误差。提出了一种全场Gamma系数校正的方法,可有效去除点云的周期性误差。通过搭建的实验平台对标准球进行测量,本文提出的方法有效地降低点云的周期性误差,球的标准偏差由0.0469mm降低至0.0183mm,球径误差均保持在0.02mm内。 展开更多
关键词 面结构光 多频外差 gamma DLP 最小二乘
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Damage mechanism of gamma-irradiated repurposed pultruded glass fibre polyester composite subjected to low-velocity impact using nondestructive techniques
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作者 Muhammad Imran Najeeb Muhammad Amir Siti Madiha +4 位作者 Agusril Syamsir Mohd Supian Abu Bakar Sapizah Rahim Asyraf Arif Abu Bakar Tabrej Khan 《Defence Technology(防务技术)》 2025年第5期139-151,共13页
Investigating the influence of radiation on glass fibre composites is essential for their use in space and aerospace environment.Gaining insight into the damage mechanisms caused by gamma irradiation,can improve the s... Investigating the influence of radiation on glass fibre composites is essential for their use in space and aerospace environment.Gaining insight into the damage mechanisms caused by gamma irradiation,can improve the safety and resilience of structures.This paper is aimed at investigating the failure mode and damage of gamma-irradiated repurposed pultruded glass fibre-reinforced polyester subjected to lowvelocity impact using three types of non-destructive techniques.Three sets of differently layered configurations(CRC,WCRW,W2CR2C)consisting of chopped(c),roving(r),and weaved(w)fibre-reinforced polyester are applied in this study.Drop hammer test is applied to evaluate the low-impact resistance properties of Gamma-irradiated composite at 100 kGy,500 kGy,and 1000 kGy.Preliminary flexural and hardness tests are conducted to further assess the behaviour of irradiated polymer composites.Further,the damage modes associated with the low-impact test are characterised using infrared thermography,flat panel digital radiography,and microscope observation.The results show that the composites irradiated with various doses display good impact resistance at 20 J,presenting minor damages in the form of dents on the surface.The irradiated CRC and WCRW display best impact resistance at 500 kGy,while W2CR2C at 1000 kGy.This shows that the layering sequence of reinforcement fibre can influence the impact resistance of irradiated composites.Apart from that,the application of non-destructive techniques show different damage mechanisms in the form resin cracks,yarn splitting/fracture,and matrix splitting when the composites are exposed at high and low irradiation doses.These findings offer valuable data for the defence industry,particularly in the areas of repair,maintenance,and the development of new materials. 展开更多
关键词 Damage mechanism Low-velocity impact gamma irradiation Non-destructive methods Composite failure analysis ENERGY
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ZiyuglycosideⅡsuppressed the progression of osteosarcoma by coordinating estrogen-related receptor gamma and p53 signaling pathway
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作者 Hang Du Dongjin Wu +7 位作者 Tianyu Zhang Ying Zhong Kaiyi Wu Xin Guo Lisong Sheng Nana Huang Chunzheng Gao Rong Sun 《Chinese Journal of Natural Medicines》 2025年第3期354-367,共14页
Osteosarcoma(OS)is the most prevalent primary malignant bone tumor affecting children and adolescents.Despite ongoing research efforts,the 5-year survival rate has remained stagnant for many years,highlighting the cri... Osteosarcoma(OS)is the most prevalent primary malignant bone tumor affecting children and adolescents.Despite ongoing research efforts,the 5-year survival rate has remained stagnant for many years,highlighting the critical need for novel drug development to enhance current treatment protocols.ZiyuglycosideⅡ(ZYGⅡ),a triterpenoid saponin extracted from S.officinalis,has recently demonstrated antitumor properties.This study evaluates the antitumor effect of ZYGⅡon osteosarcoma and elucidates its mechanism of action through the co-regulation of p53 and estrogen-related receptor gamma(ESRRG),which inhibits disease progression.The research employs in vitro experiments using multiple established osteosarcoma cell lines,as well as in vivo studies utilizing a nude mouse model of orthotopic xenograft osteosarcoma.Additionally,ESRRG shRNA was used to construct stable ESRRG-reducing OS cell lines to investigate the molecular mechanism by which ZYGⅡexerts its anti-osteosarcoma effects through the co-regulation of ESRRG and p53.Results indicate that ZYGⅡadministration led to decreased OS cell viability and reduced tumor volumes.Furthermore,cell cycles were arrested at the G_(0)/G1 phase,while the proportion of apoptotic cells increased.Expression of p53,ESRRG,p21,Bax,Cleaved Caspase-9,and Cleaved Caspase-3 proteins increased,while expression of CDK4,Cyclin D1,and Bcl-2 proteins decreased.Multiple ZYGⅡand ESRRG docking patterns were simulated through molecular docking.Comparing the pharmacodynamic response of ZYGⅡto OS cell lines with reduced ESRRG and normal expression demonstrated that ZYGⅡinhibits osteosarcoma progression,induces cell cycle arrest,and promotes cell apoptosis through the coordination of p53 and ESRRG.In conclusion,ZYGⅡinhibits osteosarcoma progression,leads to cell cycle arrest,and promotes cell apoptosis through synergistic regulation of p53 and ESRRG. 展开更多
关键词 ZiyuglycosideⅡ OSTEOSARCOMA Cell cycle arrest P53 Estrogen-related receptor gamma
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A low-consumption multiple nuclides identification algorithm for portable gamma spectrometer
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作者 Xi Huang Yong-Gang Yuan +3 位作者 Yu-Xuan Zhu Hua Chen Jin-Hui Qu Zhao-Yi Tan 《Nuclear Science and Techniques》 2025年第7期100-112,共13页
The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching.This study investigates the design of a low-consumption multiple nuclides ide... The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching.This study investigates the design of a low-consumption multiple nuclides identification algorithm for portable gamma spectrometers.First,the gamma spectra of 12 target nuclides(including the background case)were measured to create training datasets.The characteristic energies,obtained through energy calibration and full-energy peak addresses,are utilized as input features for a neural network.A large number of single-and multiple-nuclide training datasets are generated using random combinations and small-range drifting.Subsequently,a multi-label classification neural network based on a binary cross-entropy loss function is applied to export the existence probability of certain nuclides.The designed algorithm effectively reduces the computation time and storage space required by the neural network and has been successfully implemented in a portable gamma spectrometer with a running time of t_(r)<2 s.Results show that,in both validation and actual tests,the identification accuracy of the designed algorithm reaches 94.8%,for gamma spectra with a dose rate of d≈0.5μSv∕h and a measurement time t_(m)=60 s.This improves the ability to perform rapid on-site nuclide identification at important sites. 展开更多
关键词 Multiple nuclides identification Low consumption Portable gamma spectrometer Multi-label classification
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Potential role of astrocyte on gamma-aminobutyric acid tone regulation during developmental period
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作者 Erva Ozkan Wuhyun Koh 《Neural Regeneration Research》 2026年第3期1118-1119,共2页
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte... The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time. 展开更多
关键词 early developmental period developmental period brain cells neuronal proliferation synapse formation gamma aminobutyric acid ASTROCYTE GABA
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Gamma-induced positron beam generation at SLEGS
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作者 Sheng Jin Zi-Rui Hao +8 位作者 Long-Xiang Liu Kai-Jie Chen Yu-Xuan Yang Hang-Hua Xu Yue Zhang Qian-Kun Sun Zhen-Wei Wang Gong-Tao Fan Hong-Wei Wang 《Nuclear Science and Techniques》 2025年第5期1-10,共10页
Energy-variable gamma-rays are produced in Laser Compton Slant-scattering mode at the Shanghai Laser Electron Gamma Source(SLEGS),a beamline of the Shanghai Synchrotron Radiation Facility(also called Shanghai Light So... Energy-variable gamma-rays are produced in Laser Compton Slant-scattering mode at the Shanghai Laser Electron Gamma Source(SLEGS),a beamline of the Shanghai Synchrotron Radiation Facility(also called Shanghai Light Source).Based on the SLEGS energy-variable gamma-ray beam,a positron generation system composed of a gamma-ray-driven section,positron-generated target,magnet separation section and positron experimental section was designed for SLEGS.Geant4 simulation results show that the energy tunable positron beam in the energy range of 1–12.9 MeV with a flux of 3.7×10^(4)–6.9×10^(5)e^(+)∕s can be produced in this positron generation system.The positron beam generation and separation provide favorable experimental conditions for conducting nondestructive positron testing on SLEGS in the future.The positron generation system is currently under construction and will be completed in 2025. 展开更多
关键词 Shanghai Laser Electron gamma Source Monte Carlo simulation Nondestructive testing POSITRON GEANT4
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Readout electronics for the gamma detector of the HIRFL-CSR external target facility
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作者 Xian-Qin Li Hai-Bo Yang +10 位作者 Xiao-Meng Ma Chao-Jie Zou Tao Liu Xian-Cai Zhou Duo Yan Yang-Zhou Su Shu-Wen Tang Shi-Tao Wang Yu-Hong Yu Zhi-Yu Sun Cheng-Xin Zhao 《Nuclear Science and Techniques》 2025年第2期71-81,共11页
The Cooling Storage Ring of the Heavy Ion Research Facility in Lanzhou(HIRFL-CSR)was constructed to study nuclear physics,atomic physics,interdisciplinary science,and related applications.The External Target Facility(... The Cooling Storage Ring of the Heavy Ion Research Facility in Lanzhou(HIRFL-CSR)was constructed to study nuclear physics,atomic physics,interdisciplinary science,and related applications.The External Target Facility(ETF)is located in the main ring of the HIRFL-CSR.The gamma detector of the ETF is built to measure emitted gamma rays with energies below 5 MeV in the center-of-mass frame and is planned to measure light fragments with energies up to 300 MeV.The readout electronics for the gamma detector were designed and commissioned.The readout electronics consist of thirty-two front-end cards,thirty-two readout control units(RCUs),one common readout unit,one synchronization&clock unit,and one sub-trigger unit.By using the real-time peak-detection algorithm implemented in the RCU,the data volume can be significantly reduced.In addition,trigger logic selection algorithms are implemented to improve the selection of useful events and reduce the data size.The test results show that the integral nonlinearity of the readout electronics is less than 1%,and the energy resolution for measuring the 60 Co source is better than 5.5%.This study discusses the design and performance of the readout electronics. 展开更多
关键词 HIRFL-CSR gamma detector External target facility Readout electronics Readout control unit Common readout unit Peak-detection algorithm
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The alternatively spliced diacylglycerol kinase gamma-Δexon13 transcript generated under hypoxia promotes glioblastoma progression
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作者 MING YANG LIANGZHAO CHU +6 位作者 SHUKAI LIN HAN PENG NIYA LONG KAYA XU HUA YANG FENG HAN JIAN LIU 《Oncology Research》 2025年第5期1189-1198,共10页
Background:Glioblastoma(GBM)is one of the most malignant types of central nervous system tumors.Oxygen deprivation in the tumor microenvironment is thought to be an important factor in promoting GBM progression.Howeve... Background:Glioblastoma(GBM)is one of the most malignant types of central nervous system tumors.Oxygen deprivation in the tumor microenvironment is thought to be an important factor in promoting GBM progression.However,the mechanisms of hypoxia-promoted tumor progression remain elusive.Methods:Alternative splicing of diacylglycerol kinase gamma(DGKG)-Δexon13 was amplified and verified by PCR-Sanger sequencing.The functions of DGKG and DGKG-Δexon13 were analyzed by Cell counting kit-8(CCK-8),Transwell,Matrigeltranswell experiments,and in vivo orthotropic GBM animal models.Transcriptome analyses were done to find out the regulated genes.Results:In this study,we found that a new transcript DGKG-Δexon13 was generated in GBM under hypoxia via alternative splicing.Moreover,the results of CCK-8,Transwell,and Matrigel-transwell experiments showed that the proliferation,migration,and invasion abilities of U87-MG and T98G were decreased after DGKG knockdown.Compared to wild-type DGKG,DGKG-Δexon13 overexpression significantly promoted cellular proliferation,migration,and invasion abilities in GBM.Furthermore,in vivo,orthotropic GBM animal models analysis showed that the tumor volumes were much smaller in the DGKG knockdown group.However,the tumor sizes in the DGKG and DGKG-Δexon13 rescue groups were restored,especially in the DGKG-Δexon13 group.Transcriptome analysis revealed that MORC1,KLHDC7B,ATP1A2,INHBE,TMEM119,and FGD3 were altered significantly when DGKG was knocked down.IL-16,CCN2,and EFNB3 were specifically regulated by DGKG-Δexon13.Conclusions:Our study found that hypoxia-induced alternative splicing transcript DGKG-Δexon13 promotes GBM proliferation and infiltration,which might provide a new potential target for the clinical treatment and diagnosis of GBM. 展开更多
关键词 Glioblastoma(GBM) HYPOXIA Diacylglycerol kinase gamma(DGKG) Alternative splicing
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