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基于3GPP信道模型框架的低轨卫星时变信道仿真方法

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无线电通信技术 2024年第5期50卷 846-853页

作者：熊正田磊张建华唐盼黄磊夏亮姜涛北京邮电大学信息与通信工程学院北京100876 北京邮电大学电子工程学院北京100876 中国移动研究院未来研究院北京100053

低轨卫星通信网络具有高动态、广覆盖、大带宽的特点,是未来6G空天地一体化网络的重要组成部分。低轨卫星宽带信道模型在卫星通信系统设计与性能评估中至关重要。为了解低轨卫星高速移动引起的信道参数时变特性,基于3GPP信道标准的几何... 详细信息

低轨卫星通信网络具有高动态、广覆盖、大带宽的特点,是未来6G空天地一体化网络的重要组成部分。低轨卫星宽带信道模型在卫星通信系统设计与性能评估中至关重要。为了解低轨卫星高速移动引起的信道参数时变特性,基于3GPP信道标准的几何随机统计建模框架,提出了一种低轨卫星时变信道仿真方法,通过引入信道参数的空间一致性和簇生灭过程,刻画了不同仰角范围之间的过渡现象,支持低轨卫星连续移动下时变信道的仿真。仿真结果表明,在固定仰角范围内,簇角度和时延等小尺度信道参数随着低轨卫星仰角的连续变化而平稳变化;在不同仰角范围之间过渡时,呈现出簇生灭现象。该方法具有3GPP标准信道模型的优点,能够以较低的复杂度精确描述低轨卫星信道的时变特性,支持低轨卫星通信系统的设计和评估。

关键词：低轨卫星通信几何随机统计建模时变信道仿真

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红簕钩中1个新的齐墩果烷型降三萜

中草药 2024年第1期55卷 43-50页

作者：陈文娇宁小燕黄美芳卢澄生梁臣艳冯旭韦建华王柳萍广西中医药大学药学院广西南宁530200 广西优势中成药与民族药开发工程技术研究中心广西南宁530200 广西中医药大学中药学国家级实验教学示范中心广西南宁530200

目的研究红簕钩Rubus pirifolicus的化学成分。方法采用大孔树脂、硅胶、ODS、Sephadex LH-20以及半制备HPLC等方法进行分离纯化,根据波谱数据并结合文献对化合物结构进行鉴定。结果从红簕钩醋酸乙酯部位中分离得到16个化合物,分别... 详细信息

目的研究红簕钩Rubus pirifolicus的化学成分。方法采用大孔树脂、硅胶、ODS、Sephadex LH-20以及半制备HPLC等方法进行分离纯化,根据波谱数据并结合文献对化合物结构进行鉴定。结果从红簕钩醋酸乙酯部位中分离得到16个化合物,分别鉴定为梨叶悬钩子酸A(1)、acanthochlamic acid(2)、2α,3β-dihydroxyolean-13(18)-en-28-oic acid(3)、3-表-2-氧代-坡模醇酸(4)、2α,3α,19α,22α-tetrahydroxyurs-12-en-28-oicacid(5)、23-O-galloylarjungenin(6)、2α,3α,19α,24-四羟基齐墩果-12-烯-28-羧酸(7)、bellericageninB(8)、roburgenicacid(9)、2β,3β,19α-三羟基齐墩果-12-烯-23,28-二羧酸(10)、2α,3β,23-trihydroxylup-20(29)-en-28-oicacid28-O-β-D-glucopyranoside(11)、熊果酸(12)、山楂酸(13)、科罗索酸(14)、坡模酸(15)、齐墩果酸(16)。结论化合物1为新化合物,命名为梨叶悬钩子酸A,化合物2~3、5~6、8~10为首次从悬钩子属中分离得到,所有化合物均为首次从该植物中分离得到。

关键词：红簕钩齐墩果烷型降三萜梨叶悬钩子酸A acanthochlamic acid 2α 3β-dihydroxyolean-13(18)-en-28-oic acid

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白盒SM4优化算法在水印技术中的应用

电子设计工程 2024年第1期32卷 29-34页

作者：黄一平孙健华梁梓辰广西师范大学电子与信息工程学院/集成电路学院广西桂林541000 广西师范大学计算机科学与工程学院广西桂林541000

针对目前应用软件缺乏防止动态调试方法的问题,提出了一种白盒SM4算法与水印技术相结合的方法。对白盒SM4算法的仿射变换及迭代进行合理的优化,结合水印算法的关键技术,检测代码是否被篡改。如果被篡改就立即启动响应代码,通过改变其入... 详细信息

针对目前应用软件缺乏防止动态调试方法的问题,提出了一种白盒SM4算法与水印技术相结合的方法。对白盒SM4算法的仿射变换及迭代进行合理的优化,结合水印算法的关键技术,检测代码是否被篡改。如果被篡改就立即启动响应代码,通过改变其入口函数等方式,使程序失效。在满足手机应用白盒环境的前提下,其空间复杂度可降低为原来的1/2,时间效率可以提升四倍左右。通过数据计算可知,所提的白盒算法满足多样性要求,并可以抵御BGE(Billet,Gilbert,Ech-Chatbi)攻击。

关键词：白盒SM4 数字水印防篡改隐私安全 BGE攻击

Plasmonically engineered light-matter interactions in Aunanoparticle/MoS_(2) heterostructures for artificial optoelectronic synapse

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Nano Research 2022年第4期15卷 3539-3547页

作者： Zhuoran Luo Yunfei Xie Ziwei Li Yajuan Wang Lihui Li Ziyu Luo Chenguang Zhu Xin Yang Ming huang jianhua huang Delang liang Xiaoli Zhu Dong Li Anlian Pan Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan UniversityChangsha 410082China State Key Laboratory of Artificial Microstructure&Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100084China

Optoelectronic synaptic elements are emerging functional devices for the vigorous development of advanced neuromorphic computing technology in the post-Moore ***,optoelectronic devices based on transition metal dichalcogenides(TMDs)are limited to their poor mobilities and weak light-matter interactions,which still hardly exhibit superior device performances in the application of artificial ***,we demonstrate the successful fabrication of Au nanoparticle-coupled MoS_(2)heterostructures via chemical vapor deposition(CVD),where the light absorption of MoS_(2)is greatly enhanced and engineered by plasmonic *** electrons are excited from Au nanoparticles,and then injected into MoS_(2)semiconductors under the light *** plasmonically-engineered photo-gating effect at the metal-semiconductor junction is demonstrated to create optoelectronic devices with excellent synaptic behaviors,especially in ultra-sensitive excitatory postsynaptic current(EPSC,9.6×10^(-3)nA@3.4 nW·cm^(-2)),ultralow energy consumption(34.7 pJ),long-state retention time(>1,000 s),and tunable synaptic plasticity *** material system of Au-nanoparticles coupled TMDs presents unique advantages for building artificial synapses,which may lead the future development of neuromorphic electronics in optical information sensing and learning.

关键词： synapse optoelectronic device surface plasmon photo-gating MoS_(2)

An Extension of HAVE Message in BitTorrent Systems

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An Extension of HAVE Message in BitTorrent Systems

Isolated synchronous Virchow lymph node metastasis of sigmoid cancer: A case report

2006 10th International Conference on Communication Technology（ICCT 2006）

作者： Jianyong Li 1 Daoying huang 1 jianhua huang 2.chengren liang 1 Jianchun Li 1 Jie Zhang 1 1. School of Computer and Communication Engineering Zhengzhou Institute of Light Industry Zhengzhou Henan P.R.China2. National Digital Switching System Engineering & Technological R&D Center Zhengzhou Henan P.R.China

In BitTorrent systems, there are eleven types of messages for data communication between the peers, among which HAVE, REQUEST and PIECE messages are the three main transmission parts in terms of quantity and flow. In order to improve the efficiency of network transmission and decrease the management costs of file delivery, this paper investigates the mechanism of HAVE message of BitTorrent systems and propose a novel MultiHave message scheme. Experiment results show that under the environment of high bandwidth and consistent peers, together with assistant of the timer, the flow ratio of MultiHave message to HAVE message can be reduced to 11%, so MultiHave message can decrease the flow of messages and prevent the HAVE message storm efficiently. Furthermore, MultiHave message can adapt itself to various BT systems with various bandwidths. If the action of network peers is inconsistent, it can degenerate to the original HAVE message and keep the high performance of BitTorrent systems.

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来源： cnki会议评论

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World Journal of Clinical Cases 2021年第32期9卷 9917-9925页

作者： Jian-Qiao Yang liang Shang Le-Ping Li Hai-Yan Jing Kang-Di Dong Jian Jiao Chun-Shui Ye Hui-chengren Qin-Feng Xu Ping huang Jin Liu Cheeloo College of Medicine Shandong UniversityJinan 250000Shandong ProvinceChina Department of Gastroenterological Surgery Shandong Provincial HospitalJinan 250000Shandong ProvinceChina Department of Gastrointestinal Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of Gastrointestinal Surgery Shandong Provincial HospitalCheeloo College of MedicineShandong UniversityJinan 250000Shandong ProvinceChina Key Laboratory of Engineering of Shandong Province Shandong Provincial HospitalJinan 250000Shandong ProvinceChina Department of Pathology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of Gastroenterological Surgery Shandong Provincial HospitalShandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of General Surgery Huaiyin Hospital Affiliated to Shandong Provincial HospitalJinan 250000Shandong ProvinceChina Department of Gastroenterology Shandong Provincial Hospital Shandong Affiliated to First Medical UniversityJinan 250000Shandong ProvinceChina Research Center for Experimental Nuclear Medicine School of Basic Medical SciencesShandong UniversityJinan 250021Shandong ProvinceChina

BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors of the digestive *** metastases of this tumor are mostly confined to the regional lymph nodes,and distant supraclavicular lymph node metastases are very *** SUMMARY In this report,we describe a patient with sigmoid carcinoma and isolated synchronous supraclavicular lymph node metastases.A 56-year-old male presented with a left cervical mass that was confirmed as a lymph node metastasis from sigmoid cancer by several auxiliary *** 6 cycles of chemotherapy with the 5-fluorouracil,leucovorin and oxaliplatin+cetuximab regimen,the sigmoid colon tumor and Virchow’s lymph node metastasis were significantly smaller than before treatment,and no new metastatic sites were *** the effects of chemotherapy on quality of life,resection of the primary tumor was performed followed by 4 cycles of chemotherapy with the original chemotherapy ***’s lymph node dissection was selected by mutual consultation between the patient and *** the second surgery,the patient received capecitabine and cetuximab chemotherapy and did not experience recurrence or metastasis during *** In conclusion,supraclavicular lymph node metastasis without any other solid organ metastasis is a potential metastatic pathway for *** addition,after resection of the primary lesion,postoperative chemotherapy combined with supraclavicular lymph node dissection is feasible for the treatment of patients with CRC and isolated synchronous Virchow’s lymph node metastases.

关键词： Virchow’s lymph node Metastasis Colorectal cancer Case report

Zeolite-mediated hybrid Cu^(+)/Cu~0 interface for electrochemical nitrate reduction to ammonia

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Journal of Energy Chemistry 2023年第12期87卷 136-143,I0005页

作者： Jiabao Lv Angjian Wu liang Wang Yunhao Zhong Zhihao Zeng Qunxing huang Xiaoqing Lin Hao Zhang Shaojun Liu Qian Liu Songqiang Zhu Xiaodong Li jianhua Yan Zhifu Qi Hao Bin Wu State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027ZhejiangChina Baima Lake Laboratory Hangzhou 310053ZhejiangChina Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province Jiaxing Research InstituteZhejiang UniversityJiaxing 314031ZhejiangChina Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Institute for Composites Science Innovation(InCSI)and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina

The electrocatalytic conversion of reactive nitrogen species to ammonia is a promising strategy for efficient NH_(3) *** this study,we reveal that the hybrid Cu^(+)/Cu~0 interface is catalytically active for electrochemical ammonia synthesis from nitrate *** maintain the hybrid Cu^(+)/Cu~0 state at negative reaction potentials,hydrophilic zeolite is used to modify Cu/Cu_(2)O electrocatalyst,which demonstrates an impressive NH_(3) production rate of 41.65 mg h^(-1) cm^(-2)with ~100% Faradaic efficiency of ammonia synthesis at-0.6 V ***-situ Raman spectroscopy unveil the high activity originates from the zeolite reconstruction at the electrode–electrolyte interface,which protects the valence state of Cu~0/Cu^(+) site under negative potential and promotes electrochemical activity towards NH_(3) synthesis.

关键词： Electrochemical nitrate reduction reaction Ammonia synthesis In-situ Raman spectroscopy Zeolite Density functional theory

Depression accelerates gastric cancer invasion and metastasis by inducing a neuroendocrine phenotype via the catecholamine/β_(2)-AR/MACC1 axis

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Cancer Communications 2021年第10期41卷 1049-1070页

作者： Changqie Pan jianhua Wu Siting Zheng Huiying Sun Yisheng Fang Zhenhua huang Min Shi Li liang Jianping Bin Yulin Liao Jinzhang Chen Wangjun Liao Department of Oncology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515P.R.China Department of Pathology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515P.R.China Department of Cardiology Nanfang HospitalSout4hern Medical UniversityGuangzhouGuangdong 510515P.R.China

Background:Depression is a common,easily ignored,accompanied disease of gastric cancer(GC)patients and is often observed with elevated plasma catecholamine *** frequently promotes GC progression and leads to poor clinical outcomes;however,the molecular mechanisms underlying depression-induced GC progression remain poorly *** aimed to study the effects of depression on GC progression and explore possible mechanisms mediating the action of depression-associated catecholamines on ***:Depression states of GC patients were graded using the Patient Health Questionnaire-9,and plasma catecholamine levels were examined by high performance liquid chromatography coupled with tandem mass *** and invasive GC cells were examined using transwell assays,and metastatic GC niches were imaged using bioluminescence technology in a depression mouse model established with chronic unpredictable mild *** depression-like behaviors were assessed through sucrose preference,forced swimming,and tail suspension *** of the neuroendocrine phenotype were observed via RT-PCR,Western blotting,flow cytometry,and transmission electron ***:Fifty-one GC patients(age:53.61±1.79 years;cancer duration:3.71±0.33 months;depression duration:2.37±0.38 months;male-to-female ratio:1.55:1)were enrolled in the *** grade was significantly higher in GC patients showing higher plasma levels of catecholamines(epinephrine:P=0.018;noradrenaline:P=0.009),higher oncogene metastasis-associated in colon cancer-1(MACC1)level(P=0.018),and metastasis(P1).Further,depression-associated catecholamine specifically bound to the beta-2 adrenergic receptor(β_(2)-AR)and upregulated MACC1 expression,and thus promoting neuroendocrine phenotypic transformation through direct binding betweenMACC1 and ***,the neuroendocrine phenotypic transformation accelerated GC invasion in vitro and metastasis in ***

关键词： catecholamines depression gastric cancer MACC1 neuroendocrine phenotype psychological stress tumor metastasis

ERF5.1 modulates carotenoid accumulation by interacting with CCD4.1 in Lycium

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Horticulture Research 2023年第12期10卷 190-203页

作者： jianhua Zhao Yuhui Xu Haoxia Li Xinlei Zhu Yue Yin Xiyan Zhang Xiaoya Qin Jun Zhou Linyuan Duan Xiaojie liang Ting huang Bo Zhang Ru Wan Zhigang Shi Youlong Cao Wei An National Wolfberry Engineering Research Center/Wolfberry Science Research Institute Ningxia Academy of Agriculture and Forestry SciencesYinchuan750002China Institute of Forestry and Grassland Ecology Ningxia Academy of Agriculture and Forestry SciencesYinchuan750002China College of Biological Science&Engineering North Minzu UniversityYinchuan 750021China

Carotenoids are important natural pigments and have medical and health functions for *** cleavage dioxygenase 4(CCD4)and ethylene responsive factor(ERF)participate in carotenoid metabolism,but their roles in Lycium have not been ***,we annotated LbCCDs from the Lycium reference genome and found that LbCCD4.1 expression was significantly correlated with the carotenoid metabolites during Lycium five fruit developmental ***-expression of LbCCD4.1 in NQ’s leaves resulted in a series of significantly lower contents of carotenoid metabolites,includingβ-carotene andβ-***,LbERF5.1,a transcription factor belonging to the ERF family that was located in the nucleus,was *** reductions in the carotenoids,especially lutein,violaxanthin and their derivatives,were observed in over-expressing ERF5.1 transgenic NQ’s ***-expression or virus-induced gene silencing of LbERF5.1 in NQ’s leaves induced a consistent up-or down-expression,respectively,of ***,yeast one-hybrid and dual-luciferase reporter assays showed that ERF5.1 interacted with the promoter of CCD4.1 to increase its expression,and LbERF5.1 could bind to any one of the three predicted binding sites in the promoter of LbCCD4.1.A transcriptome analysis of LbERF5.1 and LbCCD4.1 over-expressed lines showed similar global transcript expression,and geranylgeranyl diphosphate synthase,phytoene synthase,lycopeneδ-cyclase cytochrome,cytochrome P450-type monooxygenase 97A,cytochrome P450-type monooxygenase 97C,and zeaxanthin epoxidase in the carotenoid biosynthesis pathway were differentially *** summary,we uncovered a novel molecular mechanism of carotenoid accumulation that involved an interaction between ERF5.1 and CCD4.1,which may be used to enhance carotenoid in Lycium.

关键词： metabolism expressing Lycium