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Diversity order of decode-and-forward MIMO relaying with transmit antenna selection

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 1-7页

作者： CAO Lei yang Hong-wen ZHANG xin yang Da-cheng School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article analyzes the diversity order of several proposed schemes, where the transmit antenna selection （TAS） strategies are combined with low-complexity decode-and-forward （DF） protocols in the multiple-input multiple-output （MIMO） relaying scenario. Although antenna selection is a suboptimal form of beamforming, it enjoys the advantages of tractable optimization and low feedback overhead. Specifically, this article proposes schemes that combine TAS strategies with fixed decode-and-forward （FDF） and selection decode-and-forward （SDF） protocols. Following that, the asymptotic expressions of outage probabilities are derived and the diversity order of the proposed schemes analyzed. These kinds of combination of transmit antenna selection strategies and low-complexity decode-and-forward protocols can achieve partial diversity order in the MIMO relaying scenario. The numerical simulations verify the analysis.

关键词： transmit antenna selection decode-and-forward MIMO relaying outage probability diversity order

纤维粘连蛋白靶向JAK/STAT3信号通路调控粘连性肠梗阻的机制

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中国现代普通外科进展 2024年第5期27卷 343-347页

作者：杨杰吴天山杨新文郭飞新疆医科大学第一附属医院急诊创伤外科新疆乌鲁木齐830054

目的:探究纤维粘连蛋白(FN)靶向JAK/STAT3信号通路调控粘连性肠梗阻的作用机制。方法:选取2019年1月—2020年12月就诊行肠切除手术的粘连性肠梗阻患者65例(观察组),同期行腹股沟疝手术患者65例(对照组),取患者肠组织及术前血液样本,采用... 详细信息

目的:探究纤维粘连蛋白(FN)靶向JAK/STAT3信号通路调控粘连性肠梗阻的作用机制。方法:选取2019年1月—2020年12月就诊行肠切除手术的粘连性肠梗阻患者65例(观察组),同期行腹股沟疝手术患者65例(对照组),取患者肠组织及术前血液样本,采用qRT-PCR、Western blot及免疫组织化学实验检测肠组织样本中FN、STAT3、p-STAT3基因及蛋白表达,采用酶联免疫吸附实验(ELISA)检测血清样本中FN表达。体外培养人肠上皮细胞系HIEC-6,采用慢病毒转染抑制细胞FN表达,采用CCK8、Transwell迁移实验观察FN对细胞增殖及分化的影响,同时采用qRT-PCR、Western Blot实验检测FN对细胞STAT3、p-STAT3表达的影响。结果:与对照组比较,观察组肠组织中FN mRNA及蛋白表达明显较高(P<0.05),STAT3、p-STAT3 mRNA及蛋白表达则明显较低(P<0.05),且观察组血清中分泌型FN含量也明显较高(P<0.05)。体外实验显示,与NC siRNA组HIEC-6细胞比较,LV-FN siRNA组HIEC-6细胞在48、72、96、120 h的增殖率均明显较低(P<0.05),细胞迁移能力也明显较低(P<0.05),其FN mRNA及蛋白表达明显较低(P<0.05),STAT3、p-STAT3 mRNA及蛋白则明显较高(P<0.05)。结论:纤维粘连蛋白在粘连性肠梗阻患者肠组织及血清中呈明显高表达,可通过JAK/STAT3信号通路的异常激活影响细胞的增殖和迁移,引起病变肠段发病。

关键词：纤维粘连蛋白 JAK/STAT3信号通路粘连性肠梗阻

Scheme for Direct Measurement of Wigner Characteristic Function for Motion of a Single Trapped Ion

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Communications in Theoretical Physics 2006年第2X期46卷 306-308页

作者： ZHANG Su-Zhen XIE Xiao-Tao yang wen-xin Department of Physics Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Center for Cold Atom Physics Wuhan Institute of Physics and Mathematics the Chinese Academy of Sciences Wuhan 430071 China Graduate School the Chinese Academy of Sciences Beijing 100080 China

In this paper, a procedure is proposed for measuring Wigner characteristic function for motion of a single trapped ion. In the scheme, the trapped ion is driven by two laser beams with different frequencies tuned to the first lower and upper vibrational sidebands, respectively. Unlike other previous scheme, our scheme does not require the displacement of the external state before the ion-laser interaction and thus our scheme night be more simple and feasible. The scheme can also be used to prepare the motional Schroedinger cat states and entangled coherent states.

关键词： Wigner characteristic function trapped ion

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设备、姿势对手过头作业肌肉疲劳的影响研究

人类工效学 2024年第3期30卷 12-17页

作者：赵川杨文鑫赵晓一青岛大学机电工程学院山东青岛266000

目的分析在手过头作业中不同设备及作业姿势对上肢肌肉疲劳发展的影响,避免上肢肌肉疲劳累积,降低与工作相关肌肉骨骼损伤(WMSDs)风险。方法设计手过头作业试验,招募16名被试,研究手肘屈曲(肩关节屈曲90°,肘关节屈曲90°)及手臂伸直(... 详细信息

目的分析在手过头作业中不同设备及作业姿势对上肢肌肉疲劳发展的影响,避免上肢肌肉疲劳累积,降低与工作相关肌肉骨骼损伤(WMSDs)风险。方法设计手过头作业试验,招募16名被试,研究手肘屈曲(肩关节屈曲90°,肘关节屈曲90°)及手臂伸直(肩关节屈曲135°,肘关节屈曲30°)姿势下不同设备重量(1.0 kg、1.5 kg和2.0 kg)对手过头作业的最大耐受时间(MET)、最大剩余肌力(F)以及主观肌肉疲劳评分(REP)的影响。结果手过头作业过程中肩部和上臂的肌肉疲劳明显,手肘屈曲使用2.0 kg设备肌肉疲劳最为显著,手臂伸直使用1.0 kg设备最不易产生肌肉疲劳累积。结论设备重量和作业姿势显著影响手过头作业肌肉疲劳,设备重量是影响手过头作业肌肉疲劳的重要因素,手肘屈曲比手臂伸直姿势下作业更易产生肌肉疲劳累积,会导致工作效率快速下降。

关键词：职业健康手过头作业上肢肌肉疲劳作业姿势主观疲劳评分(REP) 工作相关肌肉骨骼疾患(WMSDs)

聚乙二醇干扰素对核苷(酸)类似物经治与未治的HBsAg低水平慢性乙型肝炎患者48周疗效比较

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肝脏 2024年第6期29卷 635-640页

作者：郝坤艳陈宇星汪文洋朱浩沈敏阳文新于乐成南京大学医学院附属金陵医院感染科/肝病中心江苏210002 南京大学医学院附属金陵医院药学科江苏210002 南京大学医学院附属金陵医院急诊科江苏210002

目的比较聚乙二醇干扰素α(PegIFNα)对核苷(酸)类似物(NA)经治与未治HBsAg低水平慢性乙型肝炎(CHB)患者的疗效。方法纳入2018至2022年金陵医院就诊的CHB患者49例,患者的HBsAg0.05)。治疗48周获得HBsAg清除的12例CHB患者基线HBsAg为79.7... 详细信息

目的比较聚乙二醇干扰素α(PegIFNα)对核苷(酸)类似物(NA)经治与未治HBsAg低水平慢性乙型肝炎(CHB)患者的疗效。方法纳入2018至2022年金陵医院就诊的CHB患者49例,患者的HBsAg0.05)。治疗48周获得HBsAg清除的12例CHB患者基线HBsAg为79.71(6.10~206.59)IU/mL低于未获得者的202.09(115.73~9.81)IU/mL(H=226.00,P=0.01);且前者12周HBsAg为1.76(1.08~13.20)IU/mL亦低于后者的107.99(1.96~318.80)IU/mL(H=224.00,P=0.02)。这12例中基线HBsAg水平最高为484.64 IU/mL。NP组基线血清HBV DNA均<50 IU/mL;P组及C组HBV DNA水平差异无统计学意义(2.66±0.61)lgIU/mL比(2.78±0.71)lgIU/mL(t=-0.51,P=0.62)。48周后,P组HBV DNA均<50 IU/mL,C组仅1例患者HBV DNA<50 IU/mL(P<0.01)。NP组有4例患者HBeAg弱阳性(分别为4.04、4.05、2.92和1.52 S/CO),48周时有1例HBeAg阴转;P组及C组HBeAg均阴性。结论在NA经治基础上加用PegIFNα-2b治疗CHB与单用PegIFNα-2b治疗48周时的HBsAg清除率相近,但前者更易获得HBsAg清除。基线HBsAg水平越低,PegIFNα-2b治疗后越易获得HBsAg清除,尤其基线HBsAg<500 IU/mL者。

关键词： HBsAg清除功能性治愈核苷(酸)类似物聚乙二醇干扰素单用联合使用

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Different effects of 24 dietary intakes on gastroesophageal reflux disease: A mendelian randomization

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World Journal of Clinical Cases 2024年第14期12卷 2370-2381页

作者： Yu-xin Liu wen-Tao yang yang Li Department of Oncology Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Cardiovascular Chengdu Integrated TCM&Western Medicine HospitalChengdu 610041Sichuan ProvinceChina Department of Nuclear Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina

BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations are *** To explore the relationship between dietary intake and the risk of GERD,we extracted appropriate single nucleotide polymorphisms from genome-wide asso-ciation study data on 24 dietary *** methods were adopted for data analysis:Inverse variance weighting,weighted median methods,and MR-Egger's *** odds ratio(OR)and 95%confidence interval(CI)were used to eva-luate the causal association between dietary intake and *** Our univariate Mendelian randomization(UVMR)results showed significant evidence that pork intake(OR,2.83;95%CI:1.76-4.55;P=1.84×10–5),beer intake(OR,2.70,95%CI:2.00-3.64;P=6.54×10–11),non-oily fish intake(OR,2.41;95%CI:1.49-3.91;P=3.59×10–4)have a protective effect on *** addition,dried fruit intake(OR,0.37;95%CI:0.27-0.50;6.27×10–11),red wine intake(OR,0.34;95%CI:0.25-0.47;P=1.90×10-11),cheese intake(OR,0.46;95%CI:0.39-0.55;P=3.73×10-19),bread intake(OR,0.72;95%CI:0.56-0.92;P=0.0009)and cereal intake(OR,0.45;95%CI:0.36-0.57;P=2.07×10-11)were negatively associated with the risk of *** was a suggestive asso-ciation for genetically predicted coffee intake(OR per one SD increase,1.22,95%CI:1.03-1.44;P=0.019).Multi-variate Mendelian randomization further confirmed that dried fruit intake,red wine intake,cheese intake,and cereal intake directly affected *** contrast,the impact of pork intake,beer intake,non-oily fish intake,and bread intake on GERD was partly driven by the common risk factors for ***,after adjusting for all four elements,there was no longer a suggestive association between coffee intake and *** This study provides MR evidence to support the causal relationship between a broad range of dietary intake and GERD,providing new insights for the treatment and p

关键词： Dietary Gastroesophageal reflux disease Mendelian randomization Disease management Randomized controlled trial

Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： wen-Peng Bai Shi-Qing Cheng xin-yang Guo yang Wang Qiao Guo Chao-Dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

Controlled Twill Surface Structure Endowing Nanofiber Composite Membrane Excellent Electromagnetic Interference Shielding

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Nano-Micro Letters 2024年第11期16卷 255-273页

作者： Dechang Tao xin wen Chenguang yang Kun Yan Zhiyao Li wenwen Wang Dong Wang Key Laboratory of Textile Fiber and Products(Wuhan Textile University) Ministry of EducationWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry Chemical Engineering and BiotechnologyDonghua UniversityShanghai 201620People’s Republic of China

Inspired by the Chinese Knotting weave structure,an electromagnetic interference(EMI)nanofiber composite membrane with a twill surface was ***(vinyl alcohol-co-ethylene)(Pva-co-PE)nanofibers and twill nylon fabric were used as the matrix and filter templates,respectively.A Pva-co-PEMXene/silver nanowire(Pva-co-PE-MXene/AgNW,PM_(x)Ag)membrane was successfully prepared using a template *** the MXene/AgNW content was only 7.4 wt%(PM_(7.4)Ag),the EMI shielding efficiency(SE)of the composite membrane with the oblique twill structure on the surface was 103.9 dB and the surface twill structure improved the EMI by 38.5%.This result was attributed to the pre-interference of the oblique twill structure in the direction of the incident EM wave,which enhanced the probability of the electromagnetic waves randomly colliding with the MXene ***,the internal reflection and ohmic and resonance losses were *** PM_(7.4)Ag membrane with the twill structure exhibited both an outstanding tensile strength of 22.8 MPa and EMI SE/t of 3925.2 dB cm^(-1).Moreover,the PM_(x)Ag nanocomposite membranes demonstrated an excellent thermal management performance,hydrophobicity,non-flammability,and performance stability,which was demonstrated by an EMI SE of 97.3%in a high-temperature environment of 140℃.The successful preparation of surface-twill composite membranes makes it difficult to achieve both a low filler content and a high EMI SE in electromagnetic shielding *** strategy provides a new approach for preparing thin membranes with excellent EMI properties.

关键词： Twill surface structure MXene/AgNW Nanofiber membrane Electromagnetic interference Flexibility and mechanical properties

Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

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Chinese Journal of Polymer Science 2024年第3期42卷 299-310,I0005页

作者： Ni Chen Fei-Yu Luo Gong-wen yang Jin-Rong Yao xin Chen Zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization ***, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization