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The Analysis of Relationship between MSTN/Smad Signal Path and Turpan Black Sheep Meat Production
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作者 ANWAR Reheman TULAILIJIANG Hamutai +1 位作者 JUKEN Aniwashen YIMING Sulaiman 《Agricultural Science & Technology》 CAS 2016年第1期38-41,47,共5页
The research analyzed the expression and difference of MSTN/Smad signal path genes(MSTN, Smad2, Smad3,Smad4, TGFBR1, TGFBR2) in Turpan black sheep muscle tissue, as well as the correlation with some growth indices. Be... The research analyzed the expression and difference of MSTN/Smad signal path genes(MSTN, Smad2, Smad3,Smad4, TGFBR1, TGFBR2) in Turpan black sheep muscle tissue, as well as the correlation with some growth indices. Besides,the research used the fluorescence quantitative PCR technique to detect the expression level of MSTN, Smad2, Smad3, Smad4,TGFBR1 and TGFBR2 genes in m RNA of Turpan black sheep muscle. The research also used conventional and histological methods to determine the muscle growth and meat producibility indices, discussed the relationship between MSTN/Smad signal path and muscle growth and meat production. The result shows that these genes are expressed in Turpan black sheep muscle tissues, and have some relationship with body weight, height, length, chest circumference, hoof circumference, carcass and dressing percentage. The MSTN gene is negatively correlated with body weight(r = 0.993, P < 0.05), and hoof circumference(r= 0.957, p < 0.01), but has no significant correlation with body height, length, carcass weight, dressing percentages(P > 0.05);Smad2 gene shows significantly negative correlation the with dressing percentage(r = 0.918, p < 0.05), but no significant correlation with body weight, height, length, chest circumference, hoof circumference and carcass(P > 0.05); Smad3 gene shows no significant correlation with any of them(P > 0.05); Smad4, TGFBR1, TGFBR2 did not show any significant relationship with body height, length, chest circumference, weight and dressing percentage(P > 0.05). 展开更多
关键词 Turpan black sheep MSTN/Smad signal path gene Gene expression Growth index
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Signal Path Reckoning Localization Method in Multipath Environment 被引量:6
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作者 Junhui Zhao Lei Li +1 位作者 Hao Zhang Yi Gong 《China Communications》 SCIE CSCD 2017年第3期182-189,共8页
In the wireless localization application, multipath propagation seriously affects the localization accuracy. This paper presents two algorithms to solve the multipath problem. Firstly, we improve the Line of Possible ... In the wireless localization application, multipath propagation seriously affects the localization accuracy. This paper presents two algorithms to solve the multipath problem. Firstly, we improve the Line of Possible Mobile Device(LPMD) algorithm by optimizing the utilization of the direct paths for single-bound scattering scenario. Secondly, the signal path reckoning method with the assistance of geographic information system is proposed to solve the problem of localization with multi-bound scattering paths. With the building model's idealization, the proposed method refers to the idea of ray tracing and dead reckoning. According to the rule of wireless signal reflection, the signal propagation path is reckoned using the measurements of emission angle and propagation distance, and then the estimated location can be obtained. Simulation shows that the proposed method obtains better results than the existing geometric localization methods in multipath environment when the angle error is controlled. 展开更多
关键词 wireless localization multipath propagation signal reflection path reckoning
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A study of acupoint specificity and mechanism of electroacupuncture intervention on chronic colitis in rats based on PI3K/AKT/mTOR signaling pathway
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作者 TANG Kun-peng LV Jia-qi +4 位作者 WEN Tan ZHANG Chun-qing MA Meng-na REN Hua-shan YAN Li-ping 《Journal of Hainan Medical University》 CAS 2023年第9期33-39,共7页
Objective:This study aimed to elucidate the differences in effects and mechanisms of action of electric-needle therapy at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)acupoints on chronic expe... Objective:This study aimed to elucidate the differences in effects and mechanisms of action of electric-needle therapy at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)acupoints on chronic experimental colitis in rats through the PI3K/AKT/mTOR signaling pathway.Methods:Sixty pathogen-free SD rats were randomly assigned to six groups:the normal,model,Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)groups,each with 10 rats.Chronic colitis was induced in rats by combining immunization and local stimulation.After model establishment,electrical needle intervention combined with dispersing wave of 2 Hz/50 Hz with a current intensity of 2 mA once daily for 20 min was applied on acupoints of each group.Subsequently,the inflammation of colonic mucosa and serum levels of inflammatory factors(IL-23,IL-17,IL-10)were observed;ELISA was used to detect mRNA expressions of PI3K,Akt and mTOR in colitic tissues by RT-PCR as well as protein content of p-PI3k/PI3K,p-Akt/Akt,and p-mTOR/mTOR in colitic tissues by Western blotting.Result:Compared with the normal group,the model rats showed a poor general condition,serious damage to the colonic mucosa with a large number of inflammatory cells infiltration.The serum IL-23 and IL-17 expressions were significantly increased(P<0.01),while the serum IL-10 expression was significantly decreased(P<0.01);the mRNA and protein expressions of PI3K,Akt,mTOR and p-PI3K,p-Akt and p-mTOR were significantly increased(P<0.05,P<0.01).Compared with the model group,the pathological slices of rats in each acupoints intervention group showed obvious improvement of colitis inflammatory reaction and tissue damage;the serological levels of IL-23 and IL-17 were significantly reduced(P<0.01),while the serology level of IL-10 was significantly increased(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Compared with Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)groups,the recovery degree of mucosa layers in Shang Ju Xu(ST37)group was closer to that of normal group,and the curative effect was relatively the best;in terms of serological levels of IL-23 and IL-17,the Shang Ju Xu(ST37)group was significantly lower(P<0.05),while the level of IL-10 was significantly higher(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Conclusion:Results indicate that electrical acupuncture at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)show similar effects in relieving the colitis-induced damage in the mucosa of chronic colitis rats,as well as inflammatory response.Among them,Shang Ju Xu(ST25)has a superior overall effect in treating chronic colitis compared to Tian Shu(ST25),Da Chang Shu(BL25)and Zu San Li(ST36).The mechanism may be related to inhibition of PI3K/Akt/mTOR signaling pathway. 展开更多
关键词 ELECTROACUPUNCTURE Chronic colitis Acupoint specificity PI3K/Akt/mTOR signal path
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The Study on the Function of BAG-1Gene and its Related Signaling Pathway in Human Lung Cancer Cells
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作者 Yonggang LIANG Yu FAN Li MA Jun CHEN Sen WEI Zhigang LI Hongyu LIU Haisu WAN Zhihao WU Qinghua ZHOU 《中国肺癌杂志》 CAS 2009年第6期509-510,共2页
Background and Objective Apotosis is a programmed cell death process which can be induced by ectoor intra-cellular signals. Recent study indicates that genesis and development
关键词 BAG-1 肺癌 癌细胞 临床
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子宫内膜异位症相关信号通路及其中医药调控研究进展
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作者 张晓宇 张大伟 +2 位作者 李潇 张雪琳 马丽亚 《辽宁中医药大学学报》 2026年第2期182-190,共9页
子宫内膜异位症(endometriosis,EMS)是临床上妇科的常见病、多发病,随着现代女性社会压力的增加及不良生活方式等因素的影响,该病发生率逐年增加,严重影响了女性的身心健康。该病发病机制较为复杂,目前尚未明确。现阶段西医主要治疗方... 子宫内膜异位症(endometriosis,EMS)是临床上妇科的常见病、多发病,随着现代女性社会压力的增加及不良生活方式等因素的影响,该病发生率逐年增加,严重影响了女性的身心健康。该病发病机制较为复杂,目前尚未明确。现阶段西医主要治疗方法为激素药物、手术治疗,但由于不良反应大、复发率高,患者依从性较差,因而临床上单纯采用西医治疗的效果并不理想,故寻找一种有效、安全、经济的治疗方法是目前亟需关注的重要问题之一。相关研究发现,中医药可以通过调控丝裂原活化蛋白激酶/细胞外信号调节激酶(MAPK/ERK)、磷脂酰肌醇3激酶/蛋白激酶B(PI3K/Akt)、转化生长因子-β(TGF-β)/Smads、分泌型糖蛋白/β-连环蛋白(Wnt/β-catenin)、Toll样受体4/核转录因子-κB(TLR4/NF-κB)、酪氨酸蛋白激酶/信号转导及转录激活子(JAK/STAT)、核因子E2相关因子/Kelch样环氧氯丙烷相关蛋白1(Nrf2/Keap1)、低氧诱导因子-1α/血管内皮生长因子(HIF-1α/VEGF)、跨膜蛋白(Notch)等信号通路改善子宫内膜细胞的异常增殖与侵袭,抑制炎症反应与血管新生,干预异位内膜的凋亡与自噬过程,从而减轻临床症状,改善盆腔内环境。中医药治疗EMS有着较为明显的优势,且安全性较高,效果明显。因此基于分子细胞学角度研究EMS可以为该病的临床治疗提供一定的理论依据。然而目前对于中医药调控相关信号通路治疗EMS的系统总结较为缺乏,故该文就近年来中药有效成分及中药复方调控相关信号通路治疗该病进行系统总结归纳,为未来中医药治疗EMS提供一定的参考价值。 展开更多
关键词 子宫内膜异位症 信号通路 中医药 研究进展
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针灸调控膝骨关节炎相关信号通路的研究进展
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作者 刘洋 谢兴文 +2 位作者 李宁 宋鹏 马纪龙 《中国中医基础医学杂志》 2026年第2期433-437,共5页
针灸是中医治疗膝骨关节炎(KOA)的重要方式之一,对于延缓KOA的病程进展及减轻症状具有明确疗效。随着对KOA研究的不断深入,发现针灸可能通过干预不同信号通路起效。针灸可以直接刺激神经,激活不同信号通路的传导,达到减轻KOA滑膜炎性反... 针灸是中医治疗膝骨关节炎(KOA)的重要方式之一,对于延缓KOA的病程进展及减轻症状具有明确疗效。随着对KOA研究的不断深入,发现针灸可能通过干预不同信号通路起效。针灸可以直接刺激神经,激活不同信号通路的传导,达到减轻KOA滑膜炎性反应、阻抑膝关节病理性增生和退变的目的。本文主要从针灸调控Toll样受体(TLR)/核因子(NF)-κB、Wnt/β-连环蛋白(β-catenin)、丝裂原活化蛋白激酶(MAPK)、骨保护素(OPG)/NF-κB受体活化因子配体(RANKL)/NF-κB受体活化因子(RANK)等信号通路进行综述,为今后开展相关临床工作与实验研究提供借鉴。 展开更多
关键词 针灸 膝骨关节炎 信号通路
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MAPK通路和Wnt通路的交互作用在骨折愈合过程中的调控机制
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作者 陶炜 雷诚 +3 位作者 李欣 职晓松 项阳 王华松 《生物骨科材料与临床研究》 2026年第1期75-79,共5页
骨折愈合是一个多阶段、精密调控的生物学过程,MAPK信号通路在其中发挥重要作用。本文综述MAPK通路的组成与功能,重点阐述ERK通路通过RUNX2、ATF4和Schnurri-3等转录因子调控成骨分化的机制。同时探讨MAPK与Wnt通路的交互作用,分析其在... 骨折愈合是一个多阶段、精密调控的生物学过程,MAPK信号通路在其中发挥重要作用。本文综述MAPK通路的组成与功能,重点阐述ERK通路通过RUNX2、ATF4和Schnurri-3等转录因子调控成骨分化的机制。同时探讨MAPK与Wnt通路的交互作用,分析其在骨发育与修复中的协同调控效应。旨在为相关机制研究及临床应用提供理论依据。 展开更多
关键词 MAPK信号通路 WNT信号通路 骨折愈合 转录因子 交互作用
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TRIM47通过TAB1/IκB炎症信号通路参与急性肺损伤的机制
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作者 欧阳运萍 陈涛 +2 位作者 李鹏 赵博 杨小军 《昆明医科大学学报》 2026年第1期47-54,共8页
目的探讨Tripartite结构蛋白47(tripartite motif containing 47,TRIM47)对急性肺损伤急性肺损伤(acute lung injury,ALI)大鼠模型肺组织的影响以及对转化生长因子β激活激酶1(TGF-beta activated kinase 1,TAB1)/核因子κB抑制蛋白(inh... 目的探讨Tripartite结构蛋白47(tripartite motif containing 47,TRIM47)对急性肺损伤急性肺损伤(acute lung injury,ALI)大鼠模型肺组织的影响以及对转化生长因子β激活激酶1(TGF-beta activated kinase 1,TAB1)/核因子κB抑制蛋白(inhibitor of NF-κB,IκB)调控机制。方法构建SD大鼠ALI模型,模型组、空载体组(NC)组及si-TRIM47组诱导建立大鼠ALI模型,NC组与si-TRIM47组于建模后经尾静脉分别注射NC质粒及靶向TRIM47的siRNA干扰质粒(si-TRIM47)。干预1周后,通过苏木精-伊红(HE)染色观察各组肺组织病理学改变,ELISA检测外周血白细胞介素(Interleukin,IL)-1、IL-6、IL-10、IL-1β、肿瘤坏死因子(tumor necrosis factor,TNF-α)的表达水平,qPCR测定肺组织中TAB1及IκB的mRNA相对表达量,Western blot分析肺组织中TAB1与IκB蛋白表达水平,同时检测NF-κB入核情况;CO-IP检测TRIM47和TAB1蛋白结合情况。结果HE染色结果显示,与对照组相比,模型组和NC组的组织炎性细胞浸润程度升高(P<0.05);与模型组和NC组相比,si-TRIM47组的病理病变程度则相对较轻。ELISA检测结果显示,与对照组相比,模型组IL-1、IL-6、IL-1β、TNF-α升高(P<0.01)。与模型组和NC组相比,si-TRIM47组大鼠的IL-1、IL-6、IL-1β、TNF-α降低,而IL-10升高(P<0.01);qPCR和Western blot结果表明,与对照组相比,模型组、NC组大鼠TAB1和核蛋白NF-κB升高、IκB表达水平降低(P<0.01);与模型组和NC组相比,si-TRIM47组TAB1降低和核蛋白NF-κB降低、IκB表达水平升高(P<0.01)。此外,CO-IP实验显示,TRIM47促进TAB1蛋白表达。结论si-TRIM47可能通过抑制炎症因子释放及TAB1信号通路的激活,对ALI大鼠发挥保护作用。 展开更多
关键词 TRIM47 急性肺损伤 炎症因子 TAB1信号通路
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信号时滞对NMPC路径跟踪系统的影响机理与消减方法
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作者 白国星 伊力夏提·伊力哈木江 +3 位作者 王俊朋 孟宇 顾青 段孟滨 《工程科学学报》 北大核心 2026年第1期129-141,共13页
目前已有一些针对路径跟踪控制中信号时滞问题的研究工作,但这些工作大多针对某种特定的控制方法,而在路径跟踪控制方法中,非线性模型预测控制(Nonlinear model predictive control,NMPC)具有能够显式处理系统约束、便于实现多目标优化... 目前已有一些针对路径跟踪控制中信号时滞问题的研究工作,但这些工作大多针对某种特定的控制方法,而在路径跟踪控制方法中,非线性模型预测控制(Nonlinear model predictive control,NMPC)具有能够显式处理系统约束、便于实现多目标优化、能够有效利用被控对象前方参考路径信息等优势,但是针对NMPC路径跟踪控制系统中时滞问题的研究较不成熟,制约了这种控制方法的实际应用.为解决上述问题,开展了以下研究工作.首先构建了能够较好地孤立出时滞影响的类车机器人路径跟踪控制系统.接着分析了信号时滞对NMPC路径跟踪控制系统的影响机理,即时滞会导致控制器产生的控制信号不能适应类车机器人在执行控制信号时所处的位置.然后提出了基于增长NMPC预测时域的时滞影响消减方法,即在迭代周期不变的情况下,在无时滞系统较优预测步数的基础上增加二倍时滞周期比以上的整数.最后通过计算机仿真和实验验证了提出方法的有效性.仿真和实验结果表明,信号时滞对NMPC路径跟踪控制系统存在影响,未考虑时滞的NMPC控制算法能够在无时滞系统中实现高精确性路径跟踪,而在有时滞系统中控制失效.通过增长预测时域可以有效消减信号时滞的影响,在信号时滞约为0.2 s的仿真与实验系统中,基于该方法的NMPC控制器可以保证路径跟踪控制的位移误差幅值不超过0.1258 m,航向误差幅值不超过0.0583 rad. 展开更多
关键词 路径跟踪 信号时滞 预测控制 类车机器人 预测时域
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Total flavonoids of Scutellaria barbata improving podocyte injury induced by high glucose through Smad4/PKM2/HIF‑1α pathway
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作者 YAN Dong GU Chang‑rui ZHANG Xiang 《Journal of Hainan Medical University》 2023年第2期22-28,共7页
Objective: To observe the effect of total flavonoids of Scutellaria barbata (TF‑SB) on the injury of high glucose induced podocytes (MPC‑5) and the influence of Smad4/PKM2/HIF‑1α pathway. Methods: Firstly, CCK8 was u... Objective: To observe the effect of total flavonoids of Scutellaria barbata (TF‑SB) on the injury of high glucose induced podocytes (MPC‑5) and the influence of Smad4/PKM2/HIF‑1α pathway. Methods: Firstly, CCK8 was used to analyze the safety and efficacy concentration of TF‑SB on MPC‑5 cells. Then, MPC‑5 was then divided into the control group, model group and TF‑SB group. In addition to the control group, model group and TF‑SB group were induced by high glucose to establish MPC‑5 cell injury model. The effects of TF‑SB on ATP, apoptosis and ROS levels of MPC‑5 cells were detected respectively. The contents of IL‑1β, TNF‑α, and MCP‑1 were determined by ELISA, the expression abundance of glycolytic genes (GLU1, PFK1 and HK1) were detected by RT‑PCR. Western blot method was used to detect the expression level of related proteins in Smad4/PKM2/HIF‑1α pathway. Results: Compared with the blank group, ATP content, GLU1, PKF1 and HK1 expression abundance of MPC‑5 cells in the model group decreased significantly, apoptosis, ROS level and IL‑1 β、 TNF‑ α And MCP‑1 significantly increased (P<0.01);Compared with model group, ATP content, GLU1, PKF1 and HK1 expression abundance, apoptosis, ROS level and IL‑1β in TF‑SB group were significantly increased , TNF‑ α The contents of MCP‑1 and MCP‑1 decreased significantly (P<0.01). In addition, compared with the blank group, the model group Smad4 and HIF‑1 α The protein expression and PKM2 expression in nucleus were significantly increased, while PKM2 expression in cytoplasm was significantly decreased (P<0.01);Compared with model group, TF‑SB group Smad4, HIF‑1 α The expression of PKM2 in the nucleus and expression of PKM2 were significantly decreased, while the expression of PKM2 in the cytoplasm was significantly increased (P<0.01). Conclusion: TF‑SB promotes the mitochondrial activity of MPC‑5 cells to induce glycolysis, and then inhibits the secretion of inflammation, which may play a role in treating diabetes nephropathy by inhibiting Smad4/PKM2/HIF‑1α signaling pathway. 展开更多
关键词 TF‑SB Diabetes nephropathy PODOCYTES Smad4/PKM2/HIF‑1αsignal path
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基于chirplet path tracing-VMD的变转速信号故障特征提取
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作者 周福成 白怡凡 +2 位作者 付滋翔 何玉灵 唐贵基 《国外电子测量技术》 北大核心 2023年第9期193-198,共6页
针对变分模态分解方法在提取故障特征时处理非平稳信号能力不足的情况,提出基于线调频小波路径追踪(chirplet path tracing)的自适应改进变分模态分解(variational mode decomposition,VMD)方法。该方法首先利用线调频小波路径追踪算法... 针对变分模态分解方法在提取故障特征时处理非平稳信号能力不足的情况,提出基于线调频小波路径追踪(chirplet path tracing)的自适应改进变分模态分解(variational mode decomposition,VMD)方法。该方法首先利用线调频小波路径追踪算法由非平稳信号得到估计转速变化曲线;其次对目标信号进行等角度重采样,通过转速变化曲线将信号从时域转化为角域;再次采用奇异值分解确定角域信号的降噪阶次,当该阶次自适应变分模态分解的分量个数后,对重采样信号进行变分模态分解处理;最后对分解后的各信号分量进行Hilbert包络谱分析,从而提取故障特征。通过对齿轮箱轴承故障进行仿真和实验验证,表明该方法能有效提取变转速信号的故障特征。 展开更多
关键词 线调频小波路径追踪 变分模态分解 变转速信号 故障特征提取
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农田物联网无线信道的传播特性与模型研究
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作者 郭丽瑞 张正华 阿布都卡依木·阿布力米提 《现代农业科技》 2026年第3期144-152,156,共10页
本研究旨在分析433 MHz频段LoRa信号在昌吉市典型农田(棉花地、玉米地、西瓜地)中的路径损耗特性,为无线传感网络部署提供依据。试验通过控制气象条件和地形变量,采集不同天线高度(2.0、4.0、6.0、8.0 m)和通信距离下的信号强度数据,研... 本研究旨在分析433 MHz频段LoRa信号在昌吉市典型农田(棉花地、玉米地、西瓜地)中的路径损耗特性,为无线传感网络部署提供依据。试验通过控制气象条件和地形变量,采集不同天线高度(2.0、4.0、6.0、8.0 m)和通信距离下的信号强度数据,研究信号在不同环境和高度下的传播特性。通过自由空间模型、双射线模型、单折线对数距离模型的数据拟合,提出了一种改进的多折线对数距离模型,该模型采用改进的拟牛顿方法(L-BFGS-B)进行优化。结果表明,西瓜、棉花和玉米的改进模型均方根误差(RMSE)分别为0.79 dB、0.67 dB和2.83 dB,决定系数(R2)分别为0.94、0.99和0.94。改进后的模型在不同作物环境中的性能优于其他模型,可为农田传感网络的信道建模和无线网络部署提供更精确的参考。 展开更多
关键词 农田作物 无线传感器网络 LoRa 433 MHz 信号传播特性 路径损耗 多折线对数距离模型
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运营商光传输网络中光信号质量监测与提升的关键技术探索
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作者 胡克宁 《科技创新与应用》 2026年第2期169-172,共4页
光传输干线网络在高速业务承载中易出现功率失衡、色散失配与误码突增等信号质量问题。该文构建包含监测节点部署、多参量采集与异常感知的监测系统,提出功率动态补偿、色散智能调节与通路优化切换等提升技术,并在典型链路上完成集成部... 光传输干线网络在高速业务承载中易出现功率失衡、色散失配与误码突增等信号质量问题。该文构建包含监测节点部署、多参量采集与异常感知的监测系统,提出功率动态补偿、色散智能调节与通路优化切换等提升技术,并在典型链路上完成集成部署。结果表明系统可显著改善传输性能并提升链路稳定性,为构建高可靠性光网络提供工程支撑路径。 展开更多
关键词 光信号质量 功率补偿 色散调节 路径优化 关键技术
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消灭破坏信号完整性的元凶
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作者 OLNEY Barry “电子首席情报官”编辑组(翻译) 《印制电路信息》 2026年第1期47-51,共5页
系统探究高速印制电路板(PCB)设计中六大信号完整性挑战及其解决方案。以拟人的方式,描述“终结者”“通孔破坏者”“串扰虫”“寄生幽灵”“返回路径反叛者”“延迟之王”等信号完整性问题,深入分析上述问题的形成机制与危害。为解决... 系统探究高速印制电路板(PCB)设计中六大信号完整性挑战及其解决方案。以拟人的方式,描述“终结者”“通孔破坏者”“串扰虫”“寄生幽灵”“返回路径反叛者”“延迟之王”等信号完整性问题,深入分析上述问题的形成机制与危害。为解决阻抗不匹配、通孔残桩、串扰、寄生效应、返回路径不连续、信号延迟等问题,提出包括严格叠层规划、背钻技术、合理布线策略、平面连续性保持、低介电常数材料选择等在内的系统性解决方案。研究结果表明,采用主动预防措施和精确仿真建模,可有效消除上述信号完整性问题,提升高速PCB设计的可靠性和性能。 展开更多
关键词 高速印制电路板 信号完整性 阻抗匹配 过孔残桩 串扰 返回路径
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面向个体出行的地铁路径提取与行为模式挖掘
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作者 刘晓磊 邹国建 +4 位作者 段征宇 来逢波 陈卓琪 李振铭 李玮峰 《交通运输工程与信息学报》 2026年第1期15-24,共10页
【背景】随着地铁网络大规模建设与成网运营格局的不断完善,地铁客流量迅速增长,乘客出行需求与模式日益复杂多变,给地铁的运营管理带来新的挑战。【目标】依托手机信令数据连续追踪用户出行轨迹的优势,根据基站布设位置和辐射范围确定... 【背景】随着地铁网络大规模建设与成网运营格局的不断完善,地铁客流量迅速增长,乘客出行需求与模式日益复杂多变,给地铁的运营管理带来新的挑战。【目标】依托手机信令数据连续追踪用户出行轨迹的优势,根据基站布设位置和辐射范围确定地铁站点内产生的信令数据,结合出行活动时间等关键阈值识别单次地铁出行,进而挖掘地铁出行模式,为优化地铁服务提供支撑。【方法】基于地铁网络拓扑模型并结合Dijkstra算法,重构乘客出行路径,进而获得全过程逐日出行数据,并采用两步分类方法挖掘乘客出行行为异质性,根据出行频次将用户分为高频用户和低频用户,从出行时间、空间和路径使用特征等维度提出时间规律性、典型出行、路径混合熵等指标,再使用K-means++聚类算法对高频和低频用户进一步细分。【数据】上海市2019年5月共包含448万名地铁用户产生的4亿条手机信令数据。【结论】提取到383万位用户的3009万次出行,18%的高频用户贡献了67%的出行,而82%的低频用户仅贡献了33%的出行。其中高频用户可分为单一路径依赖型通勤群体、路径选择灵活型通勤群体、非通勤目的日常出行群体3类;低频用户可分为商务出行群体、休闲娱乐出行群体、单日游或过境出行群体3类。研究成果可为优化地铁资源配置、制定精准营销策略以及提升地铁运行管理效率提供依据。 展开更多
关键词 城市交通 路径提取 两步分类 行为模式 手机信令 个体出行
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Molecular signaling of 5-HT<sub>1A</sub>and presence of serotonergic cells in the fetal cerebral cortex
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作者 Alfonso B. M. de Oca Gabriel M. Gutiérrez Jorge H. Rodríguez 《World Journal of Neuroscience》 2013年第2期76-82,共7页
Early appearance of the serotonergic system in the fetal brain and the various effects of serotonin (5-HT) on brain morphogenesis, have given support to a neurotrophic role of serotonin. This function of serotonin is ... Early appearance of the serotonergic system in the fetal brain and the various effects of serotonin (5-HT) on brain morphogenesis, have given support to a neurotrophic role of serotonin. This function of serotonin is accomplished through a system of serotonin nerve terminals in the target regions that involves various 5-HT receptors. In visual, auditory and somatosensory cortex an early and intense serotonergic innervation is particularly important. The neuronal somata of these terminals are normally located in the mesencephalon and they have not been observed in the maturing cerebral cortex, neither in the adult brain. By using immunolabeling techniques, fluorescence and confocal microscopy, we observe the presence of both, 5-HT terminals and 5-HT cells in mesencephalon (Me, E17) and in the neopallium (Np, E13-E16) cocultures. Cells immunopositive to 5-HT and to tryptophan-5-hydroxilase are also observed in the Np on day 12 of culture. These results concerning the unexpected presence of serotonergic cells in the fetal cerebral cortex are interesting and may be of importance in corticogenesis. As it happens with other elements of the serotonergic system, the presence of these phenotypically serotonergic cells in the early cerebral cortex may be transitory and probably supporting cortex maturation processes. The molecular signaling path of the 5-HT1A receptor has also been identified. 展开更多
关键词 SEROTONERGIC System SEROTONIN Receptor 5-HT1A Molecular signaling paths
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烙灸激活Wnt信号通路干预脊髓损伤大鼠血清促进内源性神经干细胞增殖分化研究 被引量:3
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作者 夏铂 范灵 《辽宁中医杂志》 北大核心 2025年第1期180-184,I0005,共6页
目的探究烙灸激活Wnt信号通路干预脊髓损伤大鼠血清中的内源性神经干细胞增殖分化。方法采用脊髓损伤大鼠Allen′s模型。分假手术组、模型组、Wnt抑制剂组、烙灸组、烙灸+Wnt抑制剂组,干预7 d后,取各组大鼠血清。取造模成功后3 d大鼠脊... 目的探究烙灸激活Wnt信号通路干预脊髓损伤大鼠血清中的内源性神经干细胞增殖分化。方法采用脊髓损伤大鼠Allen′s模型。分假手术组、模型组、Wnt抑制剂组、烙灸组、烙灸+Wnt抑制剂组,干预7 d后,取各组大鼠血清。取造模成功后3 d大鼠脊髓组织,分离培养内源性神经干细胞。各组血清干预细胞,在7 d后观察各组细胞增殖和分化状态。采用Westernt Blot、qRT-PCR检测各组分离血清干预后内源性神经干细胞增殖分化标记物蛋白表达及基因表达情况。结果免疫荧光染色显示烙灸组内源性神经干细胞增殖及向神经元分化最显著;模型组、Wnt抑制剂组增殖分化最少。Westernt Blot、qRT-PCR检测结果均显示烙灸组最显著,Wnt抑制剂组与模型组差异不显著。结论烙灸激活脊髓损伤大鼠Wnt信号通路,促进其内源性神经干细胞增殖分化为神经元细胞及少突胶质细胞,再抑制分化为星状胶质细胞,以实现神经细胞恢复新生的目的。 展开更多
关键词 WNT信号通路 烙灸 脊髓损伤大鼠血清 内源性神经干细胞 增殖分化
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Indoor Radio Propagation Model Based on Dominant Path
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作者 Yongxiang Zhao Meifang Li Feng Shi 《International Journal of Communications, Network and System Sciences》 2010年第3期330-337,共8页
When there are bigger obstacles in the indoor environment such as elevator, the radio waves basically can not penetrate it. The contribution of received signal strength by transmission and reflection will be greatly r... When there are bigger obstacles in the indoor environment such as elevator, the radio waves basically can not penetrate it. The contribution of received signal strength by transmission and reflection will be greatly reduced, and most of the time, the radio waves will reach the user by bypass diffraction. Therefore, the traditional path loss model is no longer applicable, and the improved model should be proposed. In this paper, we firstly proposed an indoor radio propagation model based on dominant path in which the received signal strength has nothing to do with the direct distance between user and access point, but is related to the length of dominant path. Then on the basis of dominant path model, the NLOS influence is considered in order to further improve the accuracy of dominant path model. Experimental results demonstrated that the proposed dominant path model can improve the accuracy of traditional path loss model remarkably. 展开更多
关键词 Wireless LANS Indoor POSITIONING Radio WAVES RECEIVED signal Strength path Loss Model DOMINANT path
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Simulation Evaluation of Filtering Method for Improving Pedestrian Positioning Accuracy Using Signal Strengths
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作者 Yuya Nishimaki Hisato Iwai Kenya Sato 《Wireless Sensor Network》 2019年第6期81-94,共14页
In recent years, we have been able to use various services using the position information of smartphones and tablets. In addition, research on intelligent transport systems (ITS) has been actively conducted. To consid... In recent years, we have been able to use various services using the position information of smartphones and tablets. In addition, research on intelligent transport systems (ITS) has been actively conducted. To consider reducing traffic accidents by exchanging position information between pedestrians and vehicles by vehicle-to-pedestrian communication, we require accurate position information for pedestrians and vehicles. The GPS (global positioning system) is the most widely used method for acquiring position information. However, in urban areas, the GPS signal is affected by the surrounding buildings, which increases the positioning error. In this study, a method to improve the positioning accuracy of pedestrians using the signal strengths from vehicles and beacons was proposed. First, a Kalman filter was applied to the signal strength. Then, the path loss index was dynamically calculated using vehicle-to-vehicle communication. Finally, the position of a pedestrian was obtained using weighted centroid localization (WCL) after filtering the nodes. The positioning accuracy was evaluated using a simulator and demonstrated the superiority of the proposed method. 展开更多
关键词 OUTDOOR POSITIONING Vehicle-to-Pedestrian COMMUNICATION Vehicle-to-Vehicle COMMUNICATION signal Strength path Loss Index WCL
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Brief Introduction of a New Kind of Glide Path Antenna 被引量:1
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作者 Chunqing Qu 《Open Journal of Antennas and Propagation》 2018年第3期60-72,共13页
A new kind of image type glide path beacon subsystem of Instrument Landing System (ILS) was reported. Capture effect is designed to overcome far-field (FF) reflectors and rising terrain. Low angle CSB signal was highl... A new kind of image type glide path beacon subsystem of Instrument Landing System (ILS) was reported. Capture effect is designed to overcome far-field (FF) reflectors and rising terrain. Low angle CSB signal was highly depressed, was ?41 dB at 1? comparative to the max value. Both Carrier and Side Bands (CSB) and Side and Bands Only (SBO) signals were radiated by three antennas. Difference in Depth of Modulation (DDM) provided good linear variation around glide path angle (θ). At near field area, the site of near-field (NF) monitor was just about 57 m in front of the system, needed less length of reflection plane than that of M-array system, result from the system had only 90% of the M-Array antenna height. 展开更多
关键词 GLIDE path ANTENNA Near Field Monitor ANTENNA signal Analysis DDM
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