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多源星基GNSS-R地表反射率全球差异性评估及其对土壤湿度的响应
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作者 魏浩翰 蔡玉蓝 +2 位作者 徐文洲 沈哲辉 郭沈凡 《全球定位系统》 2025年第2期79-88,共10页
星基全球导航卫星系统反射测量(Global Navigation Satellite System Reflectometry,GNSS-R)技术已经成为大范围监测地表土壤湿度的一个有效手段.旋风全球导航卫星系统(Cyclone Global Navigation Satellite System,CYGNSS)以高时空分... 星基全球导航卫星系统反射测量(Global Navigation Satellite System Reflectometry,GNSS-R)技术已经成为大范围监测地表土壤湿度的一个有效手段.旋风全球导航卫星系统(Cyclone Global Navigation Satellite System,CYGNSS)以高时空分辨率的优势广泛应用于土壤湿度反演研究.2024年9月,土壤湿度主被动(soil moisture active passive,SMAP)遥感卫星首次公开了GNSS-R反射率数据.本文首先对多源GNSS-R地表反射率、SMAP卫星土壤湿度产品和第五代全球气候和天气再分析数据集(fifth generation ECMWF atmospheric reanalysis of the global climate,ERA5)土壤湿度产品进行时空匹配;其次讨论不同地理纬度、不同土地类型、不同植被光学厚度情况下CYGNSS和SMAP的星基GNSS-R地表反射率在全球范围内的差异性,并提出了基于幂律函数的经验公式模型对它们的差异进行了修正;最后分析了星基GNSS-R地表反射率对土壤湿度的响应.结果表明:CYGNSS在38°S~38°N数据量充足且分布较均匀,有利于开展地表参数反演,而SMAP数据量偏少,但能覆盖中高纬度地区,二者具有互补性;在不同地理纬度、土地类型、植被光学厚度情况下,CYGNSS和SMAP的地表反射率在数值上存在非线性差异,这与二者接收到的信号频率和极化方式不同有很大关系,前者接收的是GPS L1频段的左旋圆极化反射信号,后者接收的是GPS L2C频段的水平和垂直线性极化反射信号,可用幂律函数很好地修正它们之间的差异;CYGNSS和SMAP的地表反射率与土壤湿度整体上存在较好的相关性.研究结果有利于未来开展多源星基GNSS-R反射率联合反演地表环境参数. 展开更多
关键词 星基全球导航卫星系统反射测量(gnss-r) 地表反射率 旋风全球导航卫星系统(CYGNSS) 土壤湿度主被动(SMAP)遥感卫星 土壤湿度
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基于非线性拟合法的GNSS-R风暴潮监测
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作者 张光霁 匡翠林 陈春花 《大地测量与地球动力学》 北大核心 2025年第5期500-505,531,共7页
GNSS-R(global navigation satellite system-reflectometry)技术作为一种有效的海洋潮位监测手段已得到广泛验证,但目前常用的LSP(lomb-scargle periodogram)频谱分析方法在风暴潮监测中仍存在精度和时间分辨率偏低的问题。本文基于中... GNSS-R(global navigation satellite system-reflectometry)技术作为一种有效的海洋潮位监测手段已得到广泛验证,但目前常用的LSP(lomb-scargle periodogram)频谱分析方法在风暴潮监测中仍存在精度和时间分辨率偏低的问题。本文基于中国香港HKQT站点的观测数据,利用非线性拟合法对2018年“山竹”台风风暴潮事件开展反演研究。结合风暴潮期间风速变化数据,对比分析频谱分析法与非线性拟合法的潮位反演性能。结果显示,采用非线性拟合法的测量精度优于8 cm,与验潮站观测数据的相关系数达0.99,相较于频谱分析法潮位表达更光滑连续,有效提高了监测精度和时间分辨率,可为风暴潮灾害监测提供更加可靠的技术支持。 展开更多
关键词 gnss-r 风暴潮 潮位测量 非线性拟合法
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基于神经网络的星载GNSS-R海面高度反演误差补偿模型
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作者 马德皓 于先文 +1 位作者 王昊 郭树森 《遥感学报》 北大核心 2025年第7期2369-2381,共13页
在现阶段星载GNSS反射信号GNSS-R(Global Navigation Satellite System-Reflectometry)海面高度反演的误差研究中,使用经典误差模型对反演结果修正后仍存在较大误差。针对该问题,提出一种基于神经网络与注意力机制结合训练的误差补偿模... 在现阶段星载GNSS反射信号GNSS-R(Global Navigation Satellite System-Reflectometry)海面高度反演的误差研究中,使用经典误差模型对反演结果修正后仍存在较大误差。针对该问题,提出一种基于神经网络与注意力机制结合训练的误差补偿模型,通过误差补偿模型对海面高度反演结果进行修正,并使用DTU验证模型来评估修正精度。利用风云三号E星的星载GNSS反射信号中的多普勒延迟图DDM(Delay-Doppler Mapping)数据进行试验,并与随机森林算法和CNN算法比较模型精度。结果表明:全球定位系统GPS(Global Positioning System)反射信号的数据使用误差补偿模型修正后的平均绝对误差MAE(Mean Absolute Error)为1.74 m,北斗卫星定位系统BDS(Beidou Navigation Satellite System)反射信号的数据使用误差补偿模型修正后的MAE为0.97 m,相较经典误差模型修正精度提升了约80%;同时,本文模型相较于使用随机森林算法和CNN算法训练的模型精度稍有提升。验证结果证明,提出的误差补偿模型有效的修正了星载GNSS-R海面高度反演误差。 展开更多
关键词 gnss-r 神经网络 星载 FY-3E 海面高度反演 误差 DDM 北斗
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星载GNSS-R与散射计联合探测能力分析及其海陆典型应用
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作者 万献慈 万玮 +1 位作者 郭祉辀 胡秀清 《遥感学报》 北大核心 2025年第8期2544-2558,共15页
星载卫星导航系统反射计GNSS-R(Global Navigation Satellite System-Reflectometry)具有独特的前向散射观测方式、较高的空间分辨率以及小卫星组网条件下的高频次观测潜力,可与传统主被动微波遥感手段形成优势互补。传统的主动微波遥... 星载卫星导航系统反射计GNSS-R(Global Navigation Satellite System-Reflectometry)具有独特的前向散射观测方式、较高的空间分辨率以及小卫星组网条件下的高频次观测潜力,可与传统主被动微波遥感手段形成优势互补。传统的主动微波遥感散射计与GNSS-R空间尺度相近,二者在前、后向散射机理、主、被动观测模式等方面具有显著互补性。为寻求星载GNSS-R应用突破,本文从理论和应用两个层面,基于星载GNSS-R和散射计的工作特点,深入分析星载GNSS-R与散射计的联合探测能力,并结合海面风速、土壤湿度两个典型海陆应用场景分别进行试验。结果表明:在近实时应用场景下,二者联合比单源传感器在共同观测区域海面风速反演的均方根误差至少降低了13%;在大尺度应用场景下,具备将联合高精度优势拓展至散射计全域的可行性,将单源散射计全域土壤湿度反演的均方根误差至少降低了6%。因此,未来海陆参量反演研究可从信号源出发,针对二者的观测几何、极化组合、波段组合等在具体场景深入研究,从而拓宽反演方法及应用模式。 展开更多
关键词 星载gnss-r 散射计 前向散射 后向散射 联合反演 海面风速 土壤湿度 时延—多普勒图 反射率 归一化雷达截面
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基于神经网络反演FY-3E GNSS-R海面有效波高的固有误差分析
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作者 余辉 杜起飞 +3 位作者 夏俊明 黄飞雄 尹聪 白伟华 《测绘通报》 北大核心 2025年第10期100-105,132,共7页
风云三号(FY-3E)卫星搭载的全球卫星导航掩星探测仪器Ⅱ(GNOSⅡ)在轨获取的全球卫星导航系统反射信号遥感(GNSS-R)数据已实现海面风速、土壤湿度、海冰覆盖、海冰厚度等产品的业务化生产,并具备海面有效波高产品反演潜力。本文采用神经... 风云三号(FY-3E)卫星搭载的全球卫星导航掩星探测仪器Ⅱ(GNOSⅡ)在轨获取的全球卫星导航系统反射信号遥感(GNSS-R)数据已实现海面风速、土壤湿度、海冰覆盖、海冰厚度等产品的业务化生产,并具备海面有效波高产品反演潜力。本文采用神经网络(NN)技术,基于FY-3E卫星GNOSⅡ提供的北斗卫星导航系统反射(BDS-R)和全球定位系统反射(GPS-R)数据,构建了海浪有效波高反演模型,采用三配对数据分析方法分析了BDS-R和GPS-R反演海面有效波高的固有误差。研究结果表明,单独利用ECMWF数据评估的BDS-R和GPS-R有效波高反演精度分别为0.43和0.46 m,单独利用国家数据浮标中心(NDBC)的浮标数据评估的BDS-R和GPS-R有效波高反演精度分别为0.45和0.50 m,采用三配对数据分析方法评估的BDS-R和GPS-R有效波高固有误差分别为0.40和0.43 m,三配对数据分析方法有效降低了对比数据自身误差对评估结果的影响,BDS-R的有效波高反演精度整体优于GPS-R约7%。本文研究结果为FY-3 GNOSⅡ有效波高的业务应用提供参考。 展开更多
关键词 风云三号E星 GNOS-Ⅱ gnss-r 有效波高 神经网络 三配对分析法
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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats 被引量:1
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作者 Ping Zhang Ying Zhu +7 位作者 Pu Chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期93-109,共17页
BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling p... BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal cells.Moreover,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal cells.Cajal cells are the pacemakers of gastrointestinal motility.AIM To investigate the effects of Bifidobacterium lactis(B.lactis)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit pathway.METHODS The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 days.The tail group was given B.lactis BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/day.Hematoxylin&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and PCR.The fecal flora and mucosal flora of rats in each group were detected by 16S rRNA.RESULTS Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic intervention.Simulated microgravity reduced the expressions of SCF and c-kit,and increased the expressions of ERK and P-ERK in the gastric antrum of rats.However,after probiotic intervention,the expressions of SCF and ckit were increased,while the expressions of ERK and P-ERK were decreased,with statistical significance(P<0.05).In addition,simulated microgravity can reduce the operational taxonomic unit(OTU)of the overall intestinal flora of rats,B.lactis BLa80 can increase the OTU of rats,simulated microgravity can reduce the overall richness and diversity of stool flora of rats,increase the abundance of firmicutes in stool flora of rats,and reduce the abundance of Bacteroides in stool flora of rats,most of which are mainly beneficial bacteria.Simulated microgravity can increase the overall richness and diversity of mucosal flora,increase the abundance of Bacteroides and Desulphurides in the rat mucosal flora,and decrease the abundance of firmicutes,most of which are proteobacteria.After probiotics intervention,the overall Bacteroidetes trend in simulated microgravity rats was increased.CONCLUSION B.lactis BLa80 can ameliorate intestinal mucosal injury,regulate intestinal flora,inhibit ERK expression,and activate the SCF/c-kit signaling pathway,which may have a facilitating effect on gastrointestinal motility in simulated microgravity rats. 展开更多
关键词 Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway
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Glucocorticoid receptor signaling in the brain and its involvement in cognitive function 被引量:1
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作者 Chonglin Su Taiqi Huang +3 位作者 Meiyu Zhang Yanyu Zhang Yan Zeng Xingxing Chen 《Neural Regeneration Research》 SCIE CAS 2025年第9期2520-2537,共18页
The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an impo... The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and neuroplasticity.The glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic mechanisms.Protein interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive functions.An appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive impairment.Patients with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor expression.This review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive activities.It emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive impairment.This provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders. 展开更多
关键词 brain-derived neurotrophic factor calcium signaling glucocorticoid receptor GLUCOCORTICOID glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders NEUROPLASTICITY stress
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顾及土壤温度的星载GNSS-R土壤湿度反演
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作者 赵保睿 任玥 +2 位作者 张敏 李兵 郭明强 《地理空间信息》 2025年第5期94-97,101,共5页
为提高土壤湿度的反演精度,基于全球导航定位系统反射(GNSS-R)信号数据,提出了一种随机森林支持下顾及温度的土壤湿度反演模型。结果表明,纳入温度的预测模型的平均绝对误差和均方误差分别为0.009 cm^(3)/cm^(3)和0.0002 cm^(3)/cm^(3)... 为提高土壤湿度的反演精度,基于全球导航定位系统反射(GNSS-R)信号数据,提出了一种随机森林支持下顾及温度的土壤湿度反演模型。结果表明,纳入温度的预测模型的平均绝对误差和均方误差分别为0.009 cm^(3)/cm^(3)和0.0002 cm^(3)/cm^(3),线性拟合度升至98.7%,预测的土壤湿度与真值差值的标准差约下降28.9%;纳入温度的模型可显著提高热带草原气候区域(内陆地区)的预测精度,但在湿润地区改善不明显,反演的土壤湿度空间分布与实际观测更吻合。研究结果证实了随机森林模型在土壤湿度反演领域的应用潜力以及纳入温度对提高预测模型精度的重要性。 展开更多
关键词 随机森林 gnss-r信号 土壤湿度 土壤温度 地表反射率
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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单天线测地型接收机GNSS-R海面高度反演研究
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作者 张建锋 《地理空间信息》 2025年第6期79-82,共4页
针对双天线的全球导航卫星系统反射测量技术(GNSS-R)的局限性,对基于单天线测地型接收机的GNSS-R海面高度反演模型进行研究。利用全球5个设有常规大地测量型接收机的岸基GNSS站点的长时序信噪比数据,进行海面高度反演。结果表明,反演结... 针对双天线的全球导航卫星系统反射测量技术(GNSS-R)的局限性,对基于单天线测地型接收机的GNSS-R海面高度反演模型进行研究。利用全球5个设有常规大地测量型接收机的岸基GNSS站点的长时序信噪比数据,进行海面高度反演。结果表明,反演结果与验潮站结果相比,二者变化趋势具有高度一致性,其相关系数高于0.905。在潮差较小(2.98~4.04 m)海域,反演结果与验潮站数据互差均方根(RMS)在0.151~0.255 m范围内;在潮差较大(7.52~8.84 m)海域,二者互差RMS在0.425~0.568 m范围内。 展开更多
关键词 海面高度 gnss-r 信噪比 L-S谱分析
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Mesalazine alleviated the symptoms of spontaneous colitis in interleukin-10 knockout mice by regulating the STAT3/NF-κB signaling pathway 被引量:2
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作者 Qian Chen Ya-Li Zhang +1 位作者 Yong-Quan Shi Lie Zheng 《World Journal of Gastroenterology》 2025年第7期88-97,共10页
BACKGROUND Excessive endoplasmic reticulum(ER)stress in intestinal epithelial cells can lead to damage to the intestinal mucosal barrier,activate the signal transducer and activator of transcription 3(STAT3)/nuclear f... BACKGROUND Excessive endoplasmic reticulum(ER)stress in intestinal epithelial cells can lead to damage to the intestinal mucosal barrier,activate the signal transducer and activator of transcription 3(STAT3)/nuclear factor kappa B(NF-κB)signaling pathway,and exacerbate the inflammatory response,thus participating in the pathogenesis of ulcerative colitis(UC).Mesalazine is a commonly used drug in the clinical treatment of UC.However,further studies are needed to determine whether mesalazine regulates the ER stress of intestinal epithelial cells,downregulates the STAT3/NF-κB pathway to play a role in the treatment of UC.AIM To study the therapeutic effects of mesalazine on spontaneous colitis in interleukin-10(IL-10)-/-mice.METHODS The 24-week-old IL-10-/-mice with spontaneous colitis were divided into the model group and the 5-amino salicylic acid group.Littermates of wild-type mice of the same age group served as the control.There were eight mice in each group,four males and four females.The severity of symptoms of spontaneous colitis in IL-10-/-mice was assessed using disease activity index scores.On day 15,the mice were sacrificed.The colon length was measured,and the histopathological changes and ultrastructure of colonic epithelial cells were detected.The protein expressions of STAT3,p-STAT3,NF-κB,IκB,p-IκB,and glucoseregulated protein 78 were identified using Western blotting.The STAT3 and NF-κB mRNA expressions were identified using real-time polymerase chain reaction.The glucose-regulated protein 78 and C/EBP homologous protein expressions in colon sections were detected using immunofluorescence.RESULTS Mesalazine reduced the symptoms of spontaneous colitis in IL-10 knockout mice and the histopathological damage of colonic tissues,and alleviated the ER stress in epithelial cells of colitis mice.Western blotting and quantitative real-time polymerase chain reaction results showed that the STAT3/NF-κB pathway in the colon tissue of model mice was activated,suggesting that this pathway was involved in the pathogenesis of UC and might become a potential therapeutic target.Mesalazine could down-regulate the protein expressions of p-STAT3,NF-κB and p-IκB,and down-regulate the mRNA expression of STAT3 and NF-κB.CONCLUSION Mesalazine may play a protective role in UC by reducing ER stress by regulating the STAT3/NF-κB signaling pathway. 展开更多
关键词 MESALAZINE Ulcerative colitis Interleukin-10-/-mice signal transducer and activator of transcription 3/nuclear factor kappa B signaling pathway Endoplasmic reticulum stress Inflammatory bowel disease
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基于深度学习的GNSS-R海面高度反演模型研究
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作者 王强 《测绘学报》 北大核心 2025年第5期966-966,共1页
基于全球海面测高数据能够反演获得全球海洋重力场,进而为潜器水下重力匹配辅助导航提供数据基础。通过水下重力匹配辅助导航能够修正潜器在惯性导航中存在的系统漂移误差,有效提高潜器的隐蔽性和导航精度。因此,获得高空间分辨率和高... 基于全球海面测高数据能够反演获得全球海洋重力场,进而为潜器水下重力匹配辅助导航提供数据基础。通过水下重力匹配辅助导航能够修正潜器在惯性导航中存在的系统漂移误差,有效提高潜器的隐蔽性和导航精度。因此,获得高空间分辨率和高精度的全球海洋重力场基准图是改善水下重力匹配辅助导航的关键。 展开更多
关键词 gnss-r 全球海面测高数据 深度学习 海面高度
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基于CYGNSS卫星的星载GNSS-R台风位置反演
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作者 管栋良 周磊 +3 位作者 王亮亮 孙海文 周志凌 夏逸旻 《大地测量与地球动力学》 北大核心 2025年第7期725-731,共7页
以台风Irma为例,利用CYGNSS卫星开展基于星载GNSS-R的台风位置反演研究。实验结果表明,CYGNSS相关观测量能有效探测到台风事件的发生;利用CYGNSS观测量,基于DBSCAN聚类算法,可有效反演出台风中心位置,其最小偏差约为30 km,平均偏差约为4... 以台风Irma为例,利用CYGNSS卫星开展基于星载GNSS-R的台风位置反演研究。实验结果表明,CYGNSS相关观测量能有效探测到台风事件的发生;利用CYGNSS观测量,基于DBSCAN聚类算法,可有效反演出台风中心位置,其最小偏差约为30 km,平均偏差约为45 km。本研究有助于进一步拓宽星载GNSS-R在台风监测方面的应用范围。 展开更多
关键词 星载gnss-r CYGNSS 台风位置 风速 DBSCAN聚类算法
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Optical signal characteristics analysis of atmospheric disturbance density fields generated by high-speed aircraft 被引量:1
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作者 Yuyao WANG Xiaobing SUN +6 位作者 Yanli Qiao Wenyu CUI Yuan HU Changping YU Xiao LIU Honglian HUANG Rufang TI 《Chinese Journal of Aeronautics》 2025年第5期377-393,共17页
Aircraft disturbs the adjacent atmospheric environment in flight,forming spatial distribution features of atmospheric density that differ from the natural background,which may potentially be utilized as tracer charact... Aircraft disturbs the adjacent atmospheric environment in flight,forming spatial distribution features of atmospheric density that differ from the natural background,which may potentially be utilized as tracer characteristics to introduce new technologies for indirectly sensing the presence of aircraft.In this paper,the concept of a long-range aircraft detection based on the atmospheric disturbance density field is proposed,and the detection mode of tomographic imaging of the scattering light of an atmospheric disturbance flow field is designed.By modeling the spatial distribution of the disturbance density field,the scattered echo signal images of active light towards the disturbance field at long distance are simulated.On this basis,the characteristics of the disturbance optical signal at the optimal detection resolution are analyzed.The results show that the atmospheric disturbance flow field of the supersonic aircraft presents circular in the light-scattering echo images.The disturbance signal can be further highlighted by differential processing of the adjacent scattering images.As the distance behind the aircraft increases,the diffusion range of the disturbance signal increases,and the signal intensity and contrast with the background decrease.Under the ground-based observation conditions of the aircraft at a height of 10000 m,a Mach number of1.6,and a detection distance of 100 km,the contrast between the disturbance signal and the back-ground was 30 d B at a distance of one time from the rear of the fuselage,and the diffusion diameter of the disturbance signal was 50 m.At a distance eight times the length of the aircraft,the contrast decreased to 10 dB,and the diameter increased to 290 m.The contrast was reduced to 3 dB at a distance nine times the length of the aircraft,and the diameter was diffused to 310 m.These results indicate the possibility of long-range aircraft detection based on the characteristics of the atmospheric density field. 展开更多
关键词 AIRCRAFT Atmospheric disturbances Density fields Long-range detection signal characteristic LIDAR Active detection
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Molecular mechanism of pancreatic ductal adenocarcinoma:The heterogeneity of cancer-associated fibroblasts and key signaling pathways
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作者 Zhong-Yuan Hu Ding Ding +3 位作者 Yu Song Ya-Feng Deng Cheng-Ming Zhang Tao Yu 《World Journal of Clinical Oncology》 2025年第2期18-28,共11页
Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a d... Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a detailed exploration of epidemiological trends in pancreatic cancer and key molecular drivers,such as mutations in CDKN2A,KRAS,SMAD4,and TP53,along with the influence of cancer-associated fibroblasts(CAFs)on disease progression.In particular,we focused on the pivotal roles of signaling pathways such as the transforming growth factor-βand Wnt/β-catenin pathways in the development of pancreatic cancer and investigated their application in emerging therapeutic strategies.This study provides new scientific perspectives on pancreatic cancer treatment,especially in the development of precision medicine and targeted therapeutic strategies,and demonstrates the importance of signaling pathway research in the development of effective therapeutic regimens.Future studies should explore the subtypes of CAFs and their specific roles in the tumor microenvironment to devise more effective therapeutic methods. 展开更多
关键词 Pancreatic cancer FIBROBLASTS signaling pathways Tumor microenvironment
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NELL2,a novel osteoinductive factor,regulates osteoblast differentiation and bone homeostasis through fibronectin 1/integrin-mediated FAK/AKT signaling 被引量:1
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作者 Hairui Yuan Xinyu Wang +8 位作者 Shuanglin Du Mengyue Li Endong Zhu Jie Zhou Yuan Dong Shuang Wang Liying Shan Qian Liu Baoli Wang 《Bone Research》 2025年第4期895-909,共15页
Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was dimini... Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis. 展开更多
关键词 adipocyte differentiation osteoblast differentiation fak akt signaling FIBRONECTIN bone biology secreted protein stromal progenitor cells bone homeostasis
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Traditional Chinese medicine in the treatment of Helicobacter pylorirelated gastritis:The mechanisms of signalling pathway regulations
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作者 Pei-Pei Zhang Liang Li +3 位作者 Hao-Yu Qu Guang-Yu Chen Meng-Zhou Xie Yan-Kun Chen 《World Journal of Gastroenterology》 SCIE CAS 2025年第3期11-28,共18页
Helicobacter pylori-associated gastritis(HPAG)is a common condition of the gastrointestinal tract.However,extensive and long-term antibiotic use has resulted in numerous adverse effects,including increased resistance,... Helicobacter pylori-associated gastritis(HPAG)is a common condition of the gastrointestinal tract.However,extensive and long-term antibiotic use has resulted in numerous adverse effects,including increased resistance,gastrointestinal dysfunction,and increased recurrence rates.When these concerns develop,traditional Chinese medicine(TCM)may have advantages.TCM is based on the concept of completeness and aims to eliminate pathogens and strengthen the body.It has the potential to prevent this condition while also boosting the rate of Helicobacter pylori eradication.This review elaborates on the mechanism of TCM treatment for HPAG based on cellular signalling pathways,which reflects the flexibility of TCM in treating diseases and the advantages of multi-level,multipathway,and multi-target treatments for HPAG. 展开更多
关键词 Helicobacter pylori Helicobacter pylori-associated gastritis Traditional Chinese medicine signalling pathway Eliminate pathogens Strengthen the body
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Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases
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作者 Fengcheng Deng Dan Yang +6 位作者 Lingxi Qing Yifei Chen Jilian Zou Meiling Jia Qian Wang Runda Jiang Lihua Huang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3095-3112,共18页
The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enh... The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain axis.The gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine systems.Conversely,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host interactions.This reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological diseases.The coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological diseases.This study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological diseases.Recent pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional disorders.This can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage forms.These findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases. 展开更多
关键词 cyclic adenosine monophosphate emotional disorders gut microbiota neurodegenerative diseases neurological diseases protein kinase A reciprocal regulation signaling pathway STRATEGY THERAPIES
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Xiahuo Pingwei San (夏藿平胃散) attenuated intestinal inflammation in dextran sulfate sodium-induced ulcerative colitis mice through inhibiting the receptor for advanced glycation end-products signaling pathway 被引量:1
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作者 HUANG Jiaen LUO Qing +3 位作者 DONG Gengting PENG Weiwen HE Jianhong DAI Weibo 《Journal of Traditional Chinese Medicine》 2025年第2期311-325,共15页
OBJECTIVE:To evaluate the therapeutic effects of Xiahuo Pingwei San(夏藿平胃散,XHPWS)on ulcerative colitis(UC)in mice and to explore the underlying mechanisms through a network pharmacology approach.METHODS:Ultra-perf... OBJECTIVE:To evaluate the therapeutic effects of Xiahuo Pingwei San(夏藿平胃散,XHPWS)on ulcerative colitis(UC)in mice and to explore the underlying mechanisms through a network pharmacology approach.METHODS:Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF/MS)was utilized to identify the chemical composition and authenticate the active constituents of XHPWS,ensuring rigorous quality control across batches.A dextran sulfate sodium(DSS)-induced UC model was established in C57BL/6 mice,which were treated with XHPWS in vivo.The efficacy against UC was assessed by measuring parameters such as body weight,disease activity index(DAI)scores,and colon length.Levels of inflammatory cytokines,including interleukin-6(IL-6),interleukin-1β(IL-1β),and tumor necrosis factor-alpha(TNF-α),in colonic tissue were evaluated using enzymelinked immunosorbent assay(ELISA).Histological analysis of colon sections was conducted using hematoxylin and eosin staining.A network pharmacology approach was employed to explore the mechanisms of XHPWS and to predict its potential targets in UC treatment.Predicted protein expressions in colonic tissue were validated using immune-ohistochemistry(IHC)and Western blotting techniques.RESULTS:XHPWS effectively alle via ted DSS-induced UC symptoms in mice,as evidenced by restored body weight,reduced colon shortening,and decreased DAI scores.Histopathological examination revealed that XHPWS significantly reduced intestinal inflammatory infiltration,restored intestinal epithelial permeability,and increased goblet cell count.Network pharmacology analysis identified 63 active compounds in XHPWS and suggested that it might target 35 potential proteins associated with UC treatment.Functional enrichment analysis indicated that the protective mechanism of XHPWS could be related to the advanced glycation end products-receptor for advanced glycation end products(AGE-RAGE)signaling pathway.Notably,quercetin,kaempferol,wogonin,and nobiletin,the main components of XHPWS,showed strong correlations with the core targets.Additionally,experimental validation demonstrated that XHPWS significantly decreased levels of inflammatory cytokines interleukin 6(IL-6),interleukin 1 beta(IL-1β),and tumor necrosis factor alpha(TNF-α)in UC mice,while downregulating the expression of proteins related to the AGE-RAGE pathway.CONCLUSION:Our study demonstrated that XHPWS effectively alle via tes colitis symptoms and inflammation in UC mice,potentially through the regulation of the AGE-RAGE pathway.These findings provide strong evidence for the therapeutic potential of XHPWS in UC treatment,thereby broadening its clinical applications. 展开更多
关键词 colitis ulcerative network pharmacology inflammation glycation end products advanced receptor for advanced glycation end products signal transduction Xiahuo Pingwei San
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A Review of Deep Learning for Biomedical Signals:Current Applications,Advancements,Future Prospects,Interpretation,and Challenges
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作者 Ali Mohammad Alqudah Zahra Moussavi 《Computers, Materials & Continua》 2025年第6期3753-3841,共89页
This reviewpresents a comprehensive technical analysis of deep learning(DL)methodologies in biomedical signal processing,focusing on architectural innovations,experimental validation,and evaluation frameworks.We syste... This reviewpresents a comprehensive technical analysis of deep learning(DL)methodologies in biomedical signal processing,focusing on architectural innovations,experimental validation,and evaluation frameworks.We systematically evaluate key deep learning architectures including convolutional neural networks(CNNs),recurrent neural networks(RNNs),transformer-based models,and hybrid systems across critical tasks such as arrhythmia classification,seizure detection,and anomaly segmentation.The study dissects preprocessing techniques(e.g.,wavelet denoising,spectral normalization)and feature extraction strategies(time-frequency analysis,attention mechanisms),demonstrating their impact on model accuracy,noise robustness,and computational efficiency.Experimental results underscore the superiority of deep learning over traditional methods,particularly in automated feature extraction,real-time processing,cross-modal generalization,and achieving up to a 15%increase in classification accuracy and enhanced noise resilience across electrocardiogram(ECG),electroencephalogram(EEG),and electromyogram(EMG)signals.Performance is rigorously benchmarked using precision,recall,F1-scores,area under the receiver operating characteristic curve(AUC-ROC),and computational complexitymetrics,providing a unified framework for comparing model efficacy.Thesurvey addresses persistent challenges:synthetic data generationmitigates limited training samples,interpretability tools(e.g.,Gradient-weighted Class Activation Mapping(Grad-CAM),Shapley values)resolve model opacity,and federated learning ensures privacy-compliant deployments.Distinguished from prior reviews,this work offers a structured taxonomy of deep learning architectures,integrates emerging paradigms like transformers and domain-specific attention mechanisms,and evaluates preprocessing pipelines for spectral-temporal trade-offs.It advances the field by bridging technical advancements with clinical needs,such as scalability in real-world settings(e.g.,wearable devices)and regulatory alignment with theHealth Insurance Portability and Accountability Act(HIPAA)and General Data Protection Regulation(GDPR).By synthesizing technical rigor,ethical considerations,and actionable guidelines for model selection,this survey establishes a holistic reference for developing robust,interpretable biomedical artificial intelligence(AI)systems,accelerating their translation into personalized and equitable healthcare solutions. 展开更多
关键词 Deep learning deep models biomedical signals physiological signals biosignals
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