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Arbitrary Decode-Forward Relaying with Re-Encoded Bits Selection Strategy for Polar Codes

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China Communications 2023年第8期20卷 153-162页

作者： di guan Kai Niu Chao Dong Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we propose an arbitrary decode-forward single-relay scheme for finite blocklength polar codes,which can be applied to the general symmetric discrete memoryless relay channel with orthogonal receiver *** relay node decodes the received *** relay node selectively re-encodes the message and transmits it to the destination ***,in order to minimize the upper-bound of the block error probability,we propose a selection strategy to decide the proper re-encoded bit set by the *** results are presented to illustrate the improvement in decoding performance of the proposed scheme compared to conventional relay schemes in both additive white Gaussian noise(AWGN)channel and Rayleigh fading channel(RFC).

关键词： polar codes decode-and-forward relaying arbitrary relay channel block error rate estimation

超声内镜检查术联合腹部CT鉴别胰腺占位性病变的价值

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中国内镜杂志 2025年第1期31卷 74-79页

作者：赵伟国冯波管迪青岛市胶州中心医院影像科山东青岛266399

目的分析超声内镜检查术(EUS)联合腹部CT鉴别胰腺占位性病变的价值。方法选取2020年5月-2023年5月该院收治的胰腺占位性病变患者120例,分为良性组(n=41)和恶性组(n=79)。比较两组患者病变类型、EUS、腹部CT、联合检查和病理检查结果,绘... 详细信息

目的分析超声内镜检查术(EUS)联合腹部CT鉴别胰腺占位性病变的价值。方法选取2020年5月-2023年5月该院收治的胰腺占位性病变患者120例,分为良性组(n=41)和恶性组(n=79)。比较两组患者病变类型、EUS、腹部CT、联合检查和病理检查结果,绘制受试者操作特征曲线(ROC curve),探讨EUS、腹部CT和联合检查对胰腺占位性病变良恶性的鉴别价值。结果与良性组比较,恶性组病变直径>2 cm比例更高,差异有统计学意义(P2 cm比例更高,EUS联合腹部CT诊断胰腺占位性病变良恶性,具有较好的鉴别价值,可为疾病的早期诊治提供指导依据。

关键词：胰腺占位性病变超声内镜检查术(EUS) 腹部CT 良性恶性鉴别价值

生物质炭施用量与频率对黄壤养分和关键酶活性的影响

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环境科学 2025年第2期46卷 1065-1075页

作者：李开钰宋理洪张龑刘懿冉沁瑶杨三维陈祖拥何冠谛贵州大学农学院贵阳550025 乐山师范学院新能源材料与化学学院乐山614000 乐山西部硅材料光伏新能源产业技术研究院乐山614000

黄壤是我国南方主要地带性土壤,占全国耕地面积的28%,探索生物炭对黄壤养分及关键酶活性的调控机制,对土壤健康恢复和粮食安全具有重要意义.通过大田长期定位试验,以不施用生物炭为对照(CK),研究生物炭在5、10、20和50 t·hm^(-2)施用水... 详细信息

黄壤是我国南方主要地带性土壤,占全国耕地面积的28%,探索生物炭对黄壤养分及关键酶活性的调控机制,对土壤健康恢复和粮食安全具有重要意义.通过大田长期定位试验,以不施用生物炭为对照(CK),研究生物炭在5、10、20和50 t·hm^(-2)施用水平,不同施用频率下(一次性施用:B5、B10、B20、B50和等量炭逐年连续施用:B5-3、B10-3、B20-3、B50-3),对黄壤养分及关键酶活性的影响.结果表明,黄壤农田施用生物炭能显著提高土壤pH和EC,增加碱解氮、有效磷和有机碳含量,增强了土壤脲酶、磷酸酶、蔗糖酶和过氧化氢酶活性;且逐年连续施用的土壤养分和酶活性均高于生物炭一次性施用.生物炭施用频率和施用量对土壤pH、EC、碱解氮、有机碳、磷酸酶、蔗糖酶和过氧化氢酶活性的影响无显著交互作用;对有效磷和脲酶活性存在交互作用,对速效钾含量存在极显著交互作作用.结构方程模型表明,生物炭对土壤脲酶、过氧化氢酶、磷酸酶和蔗糖酶活性存在直接的负效应,其通过影响土壤养分间接增加酶活性.两种施用频率下,生物炭施用均能提高土壤综合肥力;一次性施用频率处理B10综合得分高于其他处理,pH、EC、碱解氮、有效磷、速效钾、有机碳含量、脲酶、磷酸酶、蔗糖酶和过氧化氢酶活性较CK分别增加了8.31%、13.28%、22.18%、10.68%、21.49%、15.40%、44.79%、16.62%、35.68%和16.62%;逐年施用频率处理B50-3综合得分高于其他处理,pH、EC、碱解氮、有效磷、速效钾、有机碳含量、脲酶、磷酸酶、蔗糖酶和过氧化氢酶活性较CK分别增加了15.11%、26.26%、11.02%、43.30%、17.29%、36.68%、20.44%、3.71%、18.38%和16.62%.综上,黄壤农田施用生物炭能提高土壤养分含量和关键酶活性,有效提高土壤生产力,等量生物炭逐年连续施用效果更优,研究可为生物炭的推广与黄壤农田改良提供科学依据与理论基础.

关键词：生物炭施用频率土壤养分酶活性结构方程模型

Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge

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Structural Durability & Health Monitoring 2024年第3期18卷 361-376页

作者： Xilong Zheng Qiong Wang di guan School of Civil and Architectural Engineering Harbin UniversityHarbin150076China

The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively.

关键词： Continuous rigid frame bridge rehabilitation long-term monitoring field load test safety standard determination

A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： Pengfei Duan Yunhe An Xiaoxiao Wei Yanjie Tian di guan Xiangwen Liu Lanqun Mao Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China College of Chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Preparation and Characterization of Biodegradable Polylactide(PLA) Microspheres Encapsulating Ginsenoside Rg3

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Chemical Research in Chinese Universities 2008年第5期24卷 588-591页

作者： LIU Cheng-bai ZHANG di LI De-guan JIANG Dan CHEN Xia College of Life Science Jilin University Changchun 130021 P. R. China

In this study, the process of a biodegradable polylactide（PLA） microsphere encapsulating ginsenoside Rg3 was first studied by the emulsion solvent evaporation method, for enhancing solubility and stability of ginsenoside Rg3. Alabum was also first used as a modifier in this method. The mean diameter of the prepared PLA microspheres containing Rg3 was 40 μm. Ginsenoside Rg3 released from the microspheres was studied by HPLC and detected by UV. It was found that the drug release curve fitted the Model Heller-Baker best.

关键词： Microparticle Ginsenoside Rg3 PEA Controlled release

REDUCTION BY HYPOPHOSPHOROUS ACID IN ORGANIC SYNTHESIS

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Chinese Chemical Letters 1993年第5期4卷 407-408页

作者： Xue WANG Ye di guan Department of Chemistry Peking UniversityBeijing 100871

Hypophosphorous acid and its salt were found to serve as a new agent for selective reduction of α,β-unsaturated carbonyl compounds under mild reaction conditions.

关键词： EtOH HO ACID REDUCTION BY HYPOPHOSPHOROUS ACID IN ORGANIC SYNTHESIS

Non-viral iPSCs:a safe way for therapy?

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Protein & Cell 2012年第4期3卷 241-245页

作者： Weiqi Zhang di guan Jing Qu Weizhou Zhang guang-Hui Liu National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Laboratory of Gene Regulation and Signal Transduction Department of PharmacologySchool of MedicineUniversity of CaliforniaSan DiegoLa JollaCA 92093USA

Patients-derived induced pluripotent stem cells(iPSCs)pro-vide an invaluable tool to study mechanisms of human dis-eases and also a limitless cellular source for clinical trans-plantation(Takahashi et al.,2007;Yu et al.,2007;Liu et al.,2011a,2011b;Zhang et al.,2012).Retrovirus-or lenti-virus-based delivery systems have been serving as main-stream methods to generate patients-derived ***-ever,genomic integrations of reprogramming factors in virally generated iPSCs not only cause insertional mutagenesis but also lead to residual expression of reprogramming factors in iPSCs and their derivatives.

关键词： al. clinical programming

Enantioselective Addition of diethylzinc to Benzaldehyde by Catalysts of Chiral Heterocyclic Ligands

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Chinese Chemical Letters 1999年第9期10卷 717-718页

作者： Yan HE Yue Lan LI Ye di guan(Department of Chemistry, Peking University, Beijing 100871) Peking Univ Dept Chem Beijing 100871 Peoples R China

Several kinds of chiral heterocyclic ligands without hydroxyl group have been synthesized and used as catalysts for the asymmetric addition of diethylzinc to benzaldehyde. These ligands promoted the formation of (S)-1... 详细信息

关键词： chiral heterocyclic ligands hydroxyl group asymmetric catalysis enantioselectivity