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The Channel Branches & Network Vessels on the Tianhui Lacquered Meridian Figurine——Taking the Heart-Regulated Channel as an Example 被引量:1
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作者 ZHOU Qi Lena Springer 《Chinese Medicine and Culture》 2024年第3期222-232,共11页
Along with the surge of unearthed medical literature and cultural relics in recent years,a network of channels in the system of medical conduit vessels(meridians) during the early Western Han dynasty has become much c... Along with the surge of unearthed medical literature and cultural relics in recent years,a network of channels in the system of medical conduit vessels(meridians) during the early Western Han dynasty has become much clearer gradually.In it,the increasing number of channel branches,network vessels and needle insertion holes(acupoints) is an important feature of the development of channel medicine during the Western Han dynasty.This is not only a reflection of the expanding requirements of the theoretical system of the main trunk channels and other vessels,but also an inevitable result of the continuous enrichment and accumulation of clinical experience.This article integrates the information about channel branches,network vessels,inscriptions,dots and further relics on the Tianhui(天回) Lacquered Meridian Figurine to compare the unearthed literature of the channel genre with the transmitted classical literature about acupuncture.The “Heart-Regulated Channel” in Medical Manuscripts on Bamboo Slips from Tianhui(《天回医简》) serves as an example to explain the occurrence,development and changes of the channel branches and network vessels in the early system of medical channels. 展开更多
关键词 Tianhui Lacquered Meridian Figurine(天回髹漆经脉人像) Tianhui Medicine Slips Heart-Regulated channel(心主之脉) channel branches Network channels
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Deep learning for joint channel estimation and feedback in massive MIMO systems 被引量:1
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作者 Jiajia Guo Tong Chen +3 位作者 Shi Jin Geoffrey Ye Li Xin Wang Xiaolin Hou 《Digital Communications and Networks》 SCIE CSCD 2024年第1期83-93,共11页
The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,th... The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive antennas.In this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO systems.Two networks are constructed to perform estimation and feedback explicitly and implicitly.The explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network parameters.Quantization module is also designed to generate data-bearing bitstreams.Simulation results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors. 展开更多
关键词 channel estimation CSI feedback Deep learning Massive MIMO FDD
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Transient receptor potential channels as predictive marker and potential indicator of chemoresistance in colon cancer 被引量:1
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作者 WEI HU THOMAS WARTMANN +5 位作者 MARCO STRECKER ARISTOTELIS PERRAKIS ROLAND CRONER ARPAD SZALLASI WENJIE SHI ULF D.KAHLERT 《Oncology Research》 SCIE 2024年第1期227-239,共13页
Transient receptor potential(TRP)channels are strongly associated with colon cancer development and progression.This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TR... Transient receptor potential(TRP)channels are strongly associated with colon cancer development and progression.This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TRP channels-associated gene signature,with further validation of signature in real world samples from our hospital treated patient samples.Kaplan-Meier(K-M)survival analysis and receiver operating characteristic(ROC)curves were employed to evaluate this gene signature’s predictive accuracy and robustness in both training and testing cohorts,respectively.Additionally,the study utilized the CIBERSORT algorithm and single-sample gene set enrichment analysis to explore the signature’s immune infiltration landscape and underlying functional implications.The support vector machine algorithm was applied to evaluate the signature’s potential in predicting chemotherapy outcomes.The findings unveiled a novel three TRP channels-related gene signature(MCOLN1,TRPM5,and TRPV4)in colon adenocarcinoma(COAD).The ROC and K-M survival curves in the training dataset(AUC=0.761;p=1.58e-05)and testing dataset(AUC=0.699;p=0.004)showed the signature’s robust predictive capability for the overall survival of COAD patients.Analysis of the immune infiltration landscape associated with the signature revealed higher immune infiltration,especially an increased presence of M2 macrophages,in high-risk group patients compared to their low-risk counterparts.High-risk score patients also exhibited potential responsiveness to immune checkpoint inhibitor therapy,evident through increased CD86 and PD-1 expression profiles.Moreover,the TRPM5 gene within the signature was highly expressed in the chemoresistance group(p=0.00095)and associated with poor prognosis(p=0.036)in COAD patients,highlighting its role as a hub gene of chemoresistance.Ultimately,this signature emerged as an independent prognosis factor for COAD patients(p=6.48e-06)and expression of model gene are validated by public data and real-world patients.Overall,this bioinformatics study provides valuable insights into the prognostic implications and potential chemotherapy resistance mechanisms associated with TRPs-related genes in colon cancer. 展开更多
关键词 Colon cancer Transient receptor potential channels Prognostic signature Chemotherapy efficiency TRPM5
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A Probing Model of Secret Key Generation Based on Channel Autocorrelation Function
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作者 Xia Enjun Hu Binjie Shen Qiaoqiao 《China Communications》 SCIE CSCD 2024年第6期163-175,共13页
Secret key generation(SKG)is a promising solution to the problem of wireless communications security.As the first step of SKG,channel probing affects it significantly.Although there have been some probing schemes,ther... Secret key generation(SKG)is a promising solution to the problem of wireless communications security.As the first step of SKG,channel probing affects it significantly.Although there have been some probing schemes,there is a lack of research on the optimization of the probing process.This study investigates how to optimize correlated parameters to maximize the SKG rate(SKGR)in the time-division duplex(TDD)mode.First,we build a probing model which includes the effects of transmitting power,the probing period,and the dimension of sample vectors.Based on the model,the analytical expression of the SKGR is given.Next,we formulate an optimization problem for maximizing the SKGR and give an algorithm to solve it.We conclude the SKGR monotonically increases as the transmitting power increases.Relevant mathematical proofs are given in this study.From the simulation results,increasing appropriately the probing period and the dimension of the sample vector could increase the SKGR dramatically compared to a yardstick,which indicates the importance of optimizing the parameters related to the channel probing phase. 展开更多
关键词 channel autocorrelation function channel probing optimization problem physical layer security secret key generation
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A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network
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作者 Xiao Li Ling Zhao +1 位作者 Zhen Dai Yonggang Lei 《China Communications》 SCIE CSCD 2024年第2期122-128,共7页
This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to... This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN). 展开更多
关键词 belief propagation channel decoding correlated noise neural network
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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RNA interference reveals chloride channel 7 gene helps short-term hypersalinity stress resistance in Hong Kong oyster Crassostrea hongkongensis
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作者 Yeshao PENG Ziao CHEN +5 位作者 Qiong DENG Zhen JIA Lingxin KONG Peng ZHU Youhou XU Zhicai SHE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1261-1271,共11页
The chloride channel 7 gene(CLC 7)of the Hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC 7.The cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region conta... The chloride channel 7 gene(CLC 7)of the Hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC 7.The cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region containing 327 bp,and an open reading frame of 2298 bp.ChCLC 7 has 96.8%and 92.1%homology with CLC 7 of Crassostrea gigas and Crassostrea virginica,respectively,and it was clustered with CLC 7 of C.gigas and C.virginica.QRT-PCR showed that ChCLC 7 was expressed in all eight tissues,with the highest in adductor muscle and second in gill.The ChCLC 7 expression pattern in gill was altered significantly under high salinity stress with an overall upward and then downward trend.After RNA interference,the expression of ChCLC 7 and survival rate of oyster under high salinity stress was reduced significantly,and so did the concentration of hemolymph chloride ion in 48-96 h after RNA interference.We believed that ChCLC 7 could play an important role in osmoregulation of C.hongkongensis by regulating Cl^(-)transport.This study provided data for the analysis of molecular mechanism against oyster salinity stress. 展开更多
关键词 Crassostrea hongkongensis chloride channel 7 salinity stress RNA interference
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Ultimately Bounded Output Feedback Control for Networked Nonlinear Systems With Unreliable Communication Channel: A Buffer-Aided Strategy
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作者 Yuhan Zhang Zidong Wang +2 位作者 Lei Zou Yun Chen Guoping Lu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1566-1578,共13页
This paper concerns ultimately bounded output-feedback control problems for networked systems with unknown nonlinear dynamics. Sensor-to-observer signal transmission is facilitated over networks that has communication... This paper concerns ultimately bounded output-feedback control problems for networked systems with unknown nonlinear dynamics. Sensor-to-observer signal transmission is facilitated over networks that has communication constraints.These transmissions are carried out over an unreliable communication channel. In order to enhance the utilization rate of measurement data, a buffer-aided strategy is novelly employed to store historical measurements when communication networks are inaccessible. Using the neural network technique, a novel observer-based controller is introduced to address effects of signal transmission behaviors and unknown nonlinear dynamics.Through the application of stochastic analysis and Lyapunov stability, a joint framework is constructed for analyzing resultant system performance under the introduced controller. Subsequently, existence conditions for the desired output-feedback controller are delineated. The required parameters for the observerbased controller are then determined by resolving some specific matrix inequalities. Finally, a simulation example is showcased to confirm method efficacy. 展开更多
关键词 Buffer-aided strategy neural networks nonlinear control output-feedback control unreliable communication channel
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Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks
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作者 Xiaoming He Yingchi Mao +3 位作者 Yinqiu Liu Ping Ping Yan Hong Han Hu 《Digital Communications and Networks》 SCIE CSCD 2024年第1期109-116,共8页
In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver u... In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference cancellation.Unfortunately,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable rate.Since the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign resources.Specifically,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power allocation.Moreover,agents in the collection stage slow down,which hinders the learning of other agents.Therefore,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler problem.The experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods. 展开更多
关键词 B5G Heterogeneous edge networks PPO channel assignment Power allocation THROUGHPUT
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Assessment of the Recent Hydromorphological Features of Nokoue Lake and Its Channels (South-East Benin)
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作者 Tètchodiwèï Julie-Billard Yonouwinhi Gérard Alfred Franck Assiom d’Almeida +1 位作者 Felix Kofi Abagale Akuemaho Virgile Onésime Akowanou 《Open Journal of Modern Hydrology》 CAS 2024年第1期33-55,共23页
Based on 2022 and 2023 hydrometric data and satellite images (Sentinel 2022, SPOT 2010), this study aims to present the Nokoué Lake and its channels’ re-cent hydromorphological characteristics. Integrating flow,... Based on 2022 and 2023 hydrometric data and satellite images (Sentinel 2022, SPOT 2010), this study aims to present the Nokoué Lake and its channels’ re-cent hydromorphological characteristics. Integrating flow, tributary morphology, and topography data determined specific power values along the axes studied. The values obtained range from 2.69 to 12.92 W/m2 for Ouémé River and 2.46 to 10.99 W/m2 for Sô River. The resulting water erosion on banks and bottoms is of linear, areolar, or gully and claw types. Lake bathymetry varies from -0.5 to -2.6 m (low flow period) and -1 to -4 m;in the Ouémé, Sô, and Totchè rivers, it varies from -5 m to -7 m, reaching -10 m at the Cotonou channel entrance (flood period). Bathymetric profiles reveal varied “U”, “V” and “Intermediate” bottom morphologies, influenced by erosion/sedimentation processes and human activities. The flow facies identified are lentic in the northern tributaries and lotic in the Cotonou and Totchè canals. Spatial analysis identified nine (09) thematic classes. In 2022, the surface area of the water body has increased from 274 km2 at low water to 280 km2 at high water, whereas in 2010 (a recent year of exceptional flooding), the surface area was 270 km2 at low water and 277 km2 at high water. Significant changes in land use are observed between 2010 and 2022. The floodplain area decreased slightly, from 421 km2 in 2010 (year of exceptional flooding) to 419 km2 in 2022. The evolution of land use shows a progressive expansion of the urban environment to the detriment of the natural environment. In the medium to long term, this trend could threaten the hydromorphological balance and even the existence of this important lagoon ecosystem. 展开更多
关键词 Nokoué Lake Ouémé River River Cotonou channel HYDROMORPHOLOGY
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Optimization of Channel Structure of Alkaline Water Electrolyzer by Using an Expanded Mesh as a Bipolar Plate
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作者 Hai-Yan Xiong Zhen-Xiao Zhu +3 位作者 Xin Gao Chen-Ming Fan Hui-Bao Luan Bing Li 《电化学(中英文)》 CAS 北大核心 2024年第9期25-38,共14页
Alkaline water electrolysis(AWE)is the most mature technology for hydrogen production by water electrolysis.Alkaline water electrolyzer consists of multiple electrolysis cells,and a single cell consists of a diaphragm... Alkaline water electrolysis(AWE)is the most mature technology for hydrogen production by water electrolysis.Alkaline water electrolyzer consists of multiple electrolysis cells,and a single cell consists of a diaphragm,electrodes,bipolar plates and end plates,etc.The existing industrial bipolar plate channel is concave-convex structure,which is manufactured by complicated and high-cost mold punching.This structure still results in uneven electrolyte flow and low current density in the electrolytic cell,further increasing in energy consumption and cost of AWE.Thereby,in this article,the electrochemical and flow model is firstly constructed,based on the existing industrial concave and convex flow channel structure of bipolar plate,to study the current density,electrolyte flow and bubble distribution in the electrolysis cell.The reliability of the model was verified by comparison with experimental data in literature.Among which,the electrochemical current density affects the bubble yield,on the other hand,the generated bubbles cover the electrode surface,affecting the active specific surface area and ohmic resistance,which in turn affects the electrochemical reaction.The result indicates that the flow velocity near the bottom of the concave ball approaches zero,while the flow velocity on the convex ball surface is significantly higher.Additionally,vortices are observed within the flow channel structure,leading to an uneven distribution of electrolyte.Next,modelling is used to optimize the bipolar plate structure of AWE by simulating the electrochemistry and fluid flow performances of four kinds of structures,namely,concave and convex,rhombus,wedge and expanded mesh,in the bipolar plate of alkaline water electrolyzer.The results show that the expanded mesh channel structure has the largest current density of 3330 A/m^(2)and electrolyte flow velocity of 0.507 m/s in the electrolytic cell.Under the same current density,the electrolytic cell with the expanded mesh runner structure has the smallest potential and energy consumption.This work provides a useful guide for the comprehensive understanding and optimization of channel structures,and a theoretical basis for the design of large-scale electrolyzer. 展开更多
关键词 Alkaline water electrolyzer Expanded mesh channel structure Numerical simulation
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CNN Channel Attention Intrusion Detection SystemUsing NSL-KDD Dataset
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作者 Fatma S.Alrayes Mohammed Zakariah +2 位作者 Syed Umar Amin Zafar Iqbal Khan Jehad Saad Alqurni 《Computers, Materials & Continua》 SCIE EI 2024年第6期4319-4347,共29页
Intrusion detection systems(IDS)are essential in the field of cybersecurity because they protect networks from a wide range of online threats.The goal of this research is to meet the urgent need for small-footprint,hi... Intrusion detection systems(IDS)are essential in the field of cybersecurity because they protect networks from a wide range of online threats.The goal of this research is to meet the urgent need for small-footprint,highly-adaptable Network Intrusion Detection Systems(NIDS)that can identify anomalies.The NSL-KDD dataset is used in the study;it is a sizable collection comprising 43 variables with the label’s“attack”and“level.”It proposes a novel approach to intrusion detection based on the combination of channel attention and convolutional neural networks(CNN).Furthermore,this dataset makes it easier to conduct a thorough assessment of the suggested intrusion detection strategy.Furthermore,maintaining operating efficiency while improving detection accuracy is the primary goal of this work.Moreover,typical NIDS examines both risky and typical behavior using a variety of techniques.On the NSL-KDD dataset,our CNN-based approach achieves an astounding 99.728%accuracy rate when paired with channel attention.Compared to previous approaches such as ensemble learning,CNN,RBM(Boltzmann machine),ANN,hybrid auto-encoders with CNN,MCNN,and ANN,and adaptive algorithms,our solution significantly improves intrusion detection performance.Moreover,the results highlight the effectiveness of our suggested method in improving intrusion detection precision,signifying a noteworthy advancement in this field.Subsequent efforts will focus on strengthening and expanding our approach in order to counteract growing cyberthreats and adjust to changing network circumstances. 展开更多
关键词 Intrusion detection system(IDS) NSL-kDD dataset deep-learning MACHINE-LEARNING CNN channel Attention network security
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Expression levels of K_(ATP)channel subunits and morphological changes in the mouse liver after exposure to radiation
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作者 Ming Zhou Tao-Sheng Li +3 位作者 Hiroshi Abe Hideo Akashi Ryoji Suzuki Yoshio Bando 《World Journal of Experimental Medicine》 2024年第2期103-113,共11页
BACKGROUND ATP sensitive K+(K_(ATP))channels are ubiquitously distributed in various of cells and tissues,including the liver.They play a role in the pathogenesis of myocardial and liver ischemia.AIM To evaluate the r... BACKGROUND ATP sensitive K+(K_(ATP))channels are ubiquitously distributed in various of cells and tissues,including the liver.They play a role in the pathogenesis of myocardial and liver ischemia.AIM To evaluate the radiation-induced changes in the expression of K_(ATP)channel subunits in the mouse liver to understand the potential role of K_(ATP)channels in radiation injury.METHODS Adult C57BL/6 mice were randomly exposed toγ-rays at 0 Gy(control,n=2),0.2 Gy(n=6),1 Gy(n=6),or 5 Gy(n=6).The livers were removed 3 and 24 h after radiation exposure.Hematoxylin and eosin staining was used for morphological observation;immunohistochemical staining was applied to determine the expression of K_(ATP)channel subunits in the liver tissue.RESULTS Compared with the control group,the livers exposed to 0.2 Gyγ-ray showed an initial increase in the expression of Kir6.1 at 3 h,followed by recovery at 24 h after exposure.Exposure to a high dose of 5.0 Gy resulted in decreased expression of Kir6.1 and increased expression of SUR2B at 24 h.However,the expression of Kir6.2,SUR1,or SUR2A had no remarkable changes at 3 and 24 h after exposure to any of these doses.CONCLUSION The expression levels of Kir6.1 and SUR2B in mouse liver changed differently in response to different radiation doses,suggesting a potential role for them in radiation-induced liver injury. 展开更多
关键词 Radiation exposure ATP-sensitive k^(+)channel MOUSE LIVER
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Side-Channel Attacks & Data Exfiltration Using Wall Outlet USB Power Adapters
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作者 Andrew Masters Vijay K. Madisetti 《Journal of Information Security》 2024年第4期433-447,共15页
The number and creativity of side channel attacks have increased dramatically in recent years. Of particular interest are attacks leveraging power line communication to 1) gather information on power consumption from ... The number and creativity of side channel attacks have increased dramatically in recent years. Of particular interest are attacks leveraging power line communication to 1) gather information on power consumption from the victim and 2) exfiltrate data from compromised machines. Attack strategies of this nature on the greater power grid and building infrastructure levels have been shown to be a serious threat. This project further explores this concept of a novel attack vector by creating a new type of penetration testing tool: an USB power adapter capable of remote monitoring of device power consumption and communicating through powerline communications. 展开更多
关键词 CYBERSECURITY Side channel Attack Power Line Communication Penetration Testing Hotplug Attack Tool
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TRPC1与BK-α的表达对大鼠糖尿病肾病的影响 被引量:1
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作者 刘红明 陈志松 +3 位作者 邹立芳 杨智雄 喻卓 胡伟 《昆明医科大学学报》 CAS 2024年第6期15-21,共7页
目的 探究瞬时受体电位C1(transient receptor potential channel 1,TRPC1)蛋白和大电导钙离子激活钾通道α亚单位(large conductance Ca^(2+)-activated K^(+)channel α subunit,BK-α)蛋白对大鼠糖尿病肾病(diabetic kidney disease,... 目的 探究瞬时受体电位C1(transient receptor potential channel 1,TRPC1)蛋白和大电导钙离子激活钾通道α亚单位(large conductance Ca^(2+)-activated K^(+)channel α subunit,BK-α)蛋白对大鼠糖尿病肾病(diabetic kidney disease,DKD)的影响。方法 将SD大鼠随机分为对照组(n=15)和模型组(n=15)。利用高脂饲料和链脲佐菌素(streptozocin,STZ)构建DKD模型。采用血糖分析仪检测大鼠血糖变化;采用全自动生化分析仪检测大鼠肾功能水平;HE染色检测肾组织的病理变化以确定造模成功。实时荧光定量PCR(RT-qPCR)和蛋白免疫印迹分别检测肾组织TRPC1和BK-α的mRNA和蛋白表达水平;免疫组化检测TRPC1和BK-α的分布和表达情况。结果 模型组大鼠空腹血糖(fasting plasma glucose,FPG)、尿白蛋白排泄率(urinary albumin excretion rates,UAER)、血尿素氮(blood urea nitrogen,BUN)和肌酐(creatinine,Cr)均显著高于对照组(P <0.01);模型组大鼠肾小管内壁细胞出现膨胀现象,部分细胞脱离;可见肾小管发生病变或死亡;此外,在许多肾小管及肾间质区域发现有中性白细胞及其残骸;以上HE染色结果提示,DKD模型复制成功。TRPC1和BK-α在肾小球部位最为丰富,且模型组大鼠肾组织中TRPC1和BK-α的mRNA和蛋白水平都显著高于对照组(P <0.05)。结论 大鼠糖尿病肾病影响TRPC1和BK-α在肾组织中的分布和表达。 展开更多
关键词 大鼠糖尿病肾病 瞬时受体电位C1蛋白 大电导钙离子激活钾通道α亚单位蛋白
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不同年龄段婴儿1177例维生素K1与K2水平分布调查分析 被引量:1
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作者 周锦妍 李克蓉 +3 位作者 马雁 王继强 张正明 李旺 《昆明医科大学学报》 CAS 2024年第1期83-86,共4页
目的探讨对比各年龄段婴儿血清维生素K1与K2水平,了解维生素K1与K2在不同年龄段婴儿体内的分布情况。方法选取课题单位(儿科、新生儿科、儿童保健科、产科)出生/就诊的儿童作为研究对象,按年龄为0~3 d(591例)、4~7 d(255例)、8~15 d(104... 目的探讨对比各年龄段婴儿血清维生素K1与K2水平,了解维生素K1与K2在不同年龄段婴儿体内的分布情况。方法选取课题单位(儿科、新生儿科、儿童保健科、产科)出生/就诊的儿童作为研究对象,按年龄为0~3 d(591例)、4~7 d(255例)、8~15 d(104例)、1个月(118例)、2个月(40例)、3个月(69例)进行分组。收集患者的一般资料,采用统一平台的高效液相色谱-质谱(LC-MS)法测定患者血清维生素K1与K2水平,从维生素K1与K2不同年龄段的水平分布,缺乏率进行数据分析。结果各年龄段的维生素K1与K2水平分布具有统计学意义(P<0.001);新生儿极易缺乏维生素K1,随着年龄增长,维生素K2的缺乏率高于维生素K1。结论维持维生素K1及K2的正常对于各年龄段婴幼儿的正常生长发育至关重要,应当密切关注婴幼儿维生素K1及K2的监测和补充。 展开更多
关键词 维生素k1 维生素k2 水平分布
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益智仁-乌药药对调控PI3K/Akt/mTOR通路介导细胞自噬保护肾小球足细胞的作用机制研究 被引量:4
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作者 尹德辉 唐诗韵 +2 位作者 吴珠 陈应奇 朱叶 《中华中医药学刊》 CAS 北大核心 2024年第1期30-34,I0004-I0006,共8页
目的研究益智仁-乌药药对通过调控PI3K/Akt/mTOR信号通路促进足细胞自噬治疗糖尿病肾病(Diabetic Nephropathy,DN)的作用。方法60只造模成功的C57BL/KSJ-db/db(以下简称db/db)小鼠随机分为模型组、二甲双胍组、缬沙坦组、益智仁-乌药药... 目的研究益智仁-乌药药对通过调控PI3K/Akt/mTOR信号通路促进足细胞自噬治疗糖尿病肾病(Diabetic Nephropathy,DN)的作用。方法60只造模成功的C57BL/KSJ-db/db(以下简称db/db)小鼠随机分为模型组、二甲双胍组、缬沙坦组、益智仁-乌药药对(低、中、高剂量)组,每组10只;另取10只C57BL/KSJ-db/m(以下简称db/m)小鼠为正常组,正常组和模型组给予生理盐水,治疗组小鼠分别给予相应药物,给药8周后检测小鼠肾脏病理学改变,足细胞自噬体数量、结构及相关蛋白表达。结果与模型组相比,益智仁-乌药药对组可显著减轻糖尿病肾病小鼠肾小球基底膜增厚情况,增加足细胞自噬体数量,显著升高自噬相关蛋白表达(P<0.05),降低PI3K/Akt/mTOR信号通路相关蛋白的表达(P<0.05)。其中益智仁-乌药药对高剂量组各指标改善优于益智仁-乌药低、中剂量组。结论益智仁-乌药药对通过抑制PI3K/Akt/mTOR信号通路激活,提高足细胞自噬水平,减轻足细胞损伤,发挥治疗糖尿病肾病的作用。 展开更多
关键词 益智仁-乌药药对 糖尿病肾病 PI3k/AkT/MTOR 足细胞 自噬
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^(252)Cf自发裂变K X射线发射与动能-电荷关系
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作者 刘超 刘世龙 +2 位作者 杨毅 冯晶 李昱兆 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第14期43-50,共8页
原子核裂变后多物理量间的关联测量是认识裂变过程直接有效的实验手段,然而由于初级裂变产物准确的电荷鉴别仍面临技术困难,电荷相关的多参数研究相对匮乏.为此,通过高分辨的低能高纯锗探测器和金硅面垒探测器开展了^(252)Cf自发裂变的... 原子核裂变后多物理量间的关联测量是认识裂变过程直接有效的实验手段,然而由于初级裂变产物准确的电荷鉴别仍面临技术困难,电荷相关的多参数研究相对匮乏.为此,通过高分辨的低能高纯锗探测器和金硅面垒探测器开展了^(252)Cf自发裂变的裂变碎片K X射线和动能的符合测量.利用K X射线可以很好地鉴别电荷数Z=39—62的裂变碎片,电荷分辨ΔZ≈0.7,K X射线产额呈现强烈的电荷相关性.借助K X射线给出了碎片平均动能和平均总动能及其分布宽度随核电荷数的分布,轻碎片动能分布具有鲜明的奇偶效应,偶Z碎片的动能比奇Z碎片的高约0.48 MeV;平均总动能在Z=52—53处达到峰值,总动能分布宽度在Z=56附近呈现凹坑,这反映了形变壳结构对断点形状的显著影响.裂变碎片K X射线发射的信息及动能-电荷关系研究可为裂变独立产额测量和裂变理论模型的检验提供必要的参考数据. 展开更多
关键词 裂变碎片 k X 射线 电荷鉴别 碎片动能
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40 K双波段长波探测器冷箱封装技术研究
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作者 王小坤 陈俊林 +2 位作者 罗少博 曾智江 李雪 《红外与激光工程》 EI CSCD 北大核心 2024年第3期41-51,共11页
冷光学技术是弱目标及多光谱红外探测的重要支撑技术。为了实现低温光学系统温度精确控制和防污染,一般多将低温光学与探测器集成在冷箱内。某高光谱相机需要1个320×64量子阱探测器和1个320×64 II类超晶格探测器共面拼接,集... 冷光学技术是弱目标及多光谱红外探测的重要支撑技术。为了实现低温光学系统温度精确控制和防污染,一般多将低温光学与探测器集成在冷箱内。某高光谱相机需要1个320×64量子阱探测器和1个320×64 II类超晶格探测器共面拼接,集成双波段微型滤光片,形成长波双波段探测杜瓦组件,探测器工作所需的40 K低温环境由脉管制冷机提供。杜瓦采用无窗口设计,并通过柔性波纹管将杜瓦外壳与冷箱外壳集成,以实现气密性集成和光校调节。针对40 K温区双波段探测器封装的三维拼接、探测器及滤光片的低应力封装、制冷机与探测器的高效热传输等难点,对探测器的三维拼接、40 K温区高效热传输、探测器低应力集成的热层结构、低应力滤光片支撑、杜瓦与制冷机耦合等进行研究,创新性提出了三点Z向调节拼接方法、探测器Al2O3载体复合钼基板和钼冷平台的热层结构、双波段滤光片集成的钼支撑结构、带应力隔离的冷平台与制冷机过盈装配的耦合方法,最终实现了40 K温区下双波段探测器平面度优于±2.06μm(RMS)、探测器的低温应力小于22.06 MPa、双波段滤光片低温形变小于8.55μm、探测器与制冷机温度梯度为2.6 K。40 K长波双波段红外探测器冷箱杜瓦组件经过2000 h通电老练和300次开关机试验验证,试验前后组件性能未发生明显变化,满足工程化应用的要求。 展开更多
关键词 杜瓦 冷光学 量子阱 二类超晶格 40 k温区
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基于IRS-1/PI3K信号轴探究补肺健脾方对COPD大鼠骨骼肌线粒体损伤的影响 被引量:2
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作者 沈婷婷 李素云 +4 位作者 李亚 轩银霜 李景梅 李高峰 韩冰洋 《中国比较医学杂志》 CAS 北大核心 2024年第3期57-67,共11页
目的探究补肺健脾方(Bufei Jianpi formula,BJF)通过调控IRS-1/PI3K信号轴对COPD大鼠骨骼肌线粒体损伤的影响。方法将60只SPF级SD大鼠随机分为空白(Control)组、COPD稳定期模型(Model)组、氨茶碱(Am)组、补肺健脾方(BJF)组、吡格列酮(P... 目的探究补肺健脾方(Bufei Jianpi formula,BJF)通过调控IRS-1/PI3K信号轴对COPD大鼠骨骼肌线粒体损伤的影响。方法将60只SPF级SD大鼠随机分为空白(Control)组、COPD稳定期模型(Model)组、氨茶碱(Am)组、补肺健脾方(BJF)组、吡格列酮(PIO)组以及补肺健脾方+吡格列酮(BJF+PIO)组,10只/组。采用烟熏加鼻腔滴菌(肺炎克雷伯杆菌)的方法建立COPD稳定期大鼠模型,自第9周开始给药至20周结束后取材,每周给予大鼠体重测量。分别对肺组织和骨骼肌组织进行常规切片与HE染色,并于光镜下观察其相应的病理学改变。分别于第0、8、20周采用非束缚全身体积描记系统观察大鼠肺功能,包括VT、PEF、EF50。采用qPCR技术检测大鼠骨骼肌组织中IRS-1、PI3K、PGC-1α以及Leptin mRNA的表达。采用Western blot技术检测大鼠骨骼肌组织中IRS-1、PI3K、AKT、p-AKT、PGC-1α、TFAM和Leptin蛋白的表达。结果光镜观察显示与Control组比,Model组肺病理可见肺泡间质以及肺支气管存有大量的炎性细胞浸润,部分肺泡壁出现断裂并融合形成气腔、纤维网被破坏等;与Model组比,用药治疗后各组肺泡壁的断裂以及纤维网的破坏均得到改善,支气管中炎性细胞浸润减轻,其中以BJF组与Am组尤为明显。用药治疗后各组骨骼肌病理与Model组比,可不同程度改善肌纤维之间排列间隙、萎缩与断裂,肌细胞胞质染色不均一等,其中以BJF组疗效较为显著。与Control组比,Model组PEF、VT和EF50第8周起显著降低(P<0.01),BJF组、BJF+PIO组和Am组可以显著提高PEF、EF50(P<0.01)。与Control组比,Model组中IRS-1、PGC-1α和PI3K mRNA与蛋白表达水平显著降低(P<0.05,P<0.01),Leptin mRNA与蛋白表达水平显著增高(P<0.01);与Model组比,BJF组IRS-1、PGC-1α、PI3K mRNA与蛋白表达水平显著增高(P<0.05,P<0.01);PIO组IRS-1 mRNA表达水平显著增高(P<0.01);BJF+PIO组PGC-1αmRNA水平显著增高(P<0.01),IRS-1、PI3K mRNA与蛋白水平显著升高(P<0.05,P<0.01);Am组中PI3K mRNA与蛋白表达水平显著增高(P<0.01);4个用药组中Leptin mRNA的表达水平均显著降低(P<0.01),除Am组外,其余3个用药组Leptin蛋白表达显著降低(P<0.01);与Control组比,Model组股四头肌组织中TFAM、p-AKT蛋白表达有明显的下降趋势,各治疗组的TFAM、p-AKT蛋白表达均有升高趋势,但无显著性差异(P>0.05)。结论补肺健脾方可通过调控IRS-1/PI3K信号轴,改善骨骼肌线粒体的损伤,同时提高PGC-1α与线粒体转录因子TFAM的表达,增强线粒体的生物合成,从而减轻肺与骨骼肌组织的病理性损伤。 展开更多
关键词 COPD 骨骼肌功能障碍 IRS-1/PI3k信号通路 补肺健脾方
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