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Reinforcement learning based energy efficient robot relay for unmanned aerial vehicles against smart jamming

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Science China(Information Sciences) 2022年第1期65卷 234-246页

作者： xiaozhen LU jingfang JIE Zihan LIN liang xiao jin LI Yanyong ZHANG Department of Information and Communication Engineering Xiamen University School of Computer Science and Technology University of Science and Technology of China School of Computer Science and Educational Software Guangzhou University

Unmanned aerial vehicles(UAVs) with limited energy resources, severe path loss, and shadowing to the ground base stations are vulnerable to smart jammers that aim to degrade the UAV communication performance and exhaust the UAV energy. The UAV anti-jamming communication performance, such as the outage probability, degrades if the robot relay is not aware of the jamming policies and the UAV network topology. In this paper, we propose a robot relay scheme for UAVs against smart jamming, which combines reinforcement learning with a function approximation approach named tile coding, to jointly optimize the robot moving distance and relay power with the unknown jamming channel states and locations. The robot mobility and relay policy are chosen based on the received jamming power, the robot received signal quality,location and energy consumption, and the bit error rate of the UAV messages. We also present a deep reinforcement learning version for the robot with sufficient computing resources. It uses three deep neural networks to choose the robot mobility and relay policy with reduced sample complexity, so as to avoid exploring dangerous policies that lead to the high outage probability of the UAV messages. The network architecture of the three networks is designed with fully connected layers instead of convolutional layers to reduce the computational complexity, which is analyzed by theoretical analyses. We provide the performance bound of the proposed schemes in terms of the bit error rate, robot energy consumption and utility based on a game-theoretic study. Simulation results show that the performance of our proposed relay schemes,including the bit error rate, the outage probability, and the robot energy consumption outperforms the existing schemes.

关键词： unmanned aerial vehicles relay jamming game theory reinforcement learning

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Enhanced stability of Fe-modified CuO-ZnO-ZrO_(2)-Al_(2)O_(3)/HZSM-5 bifunctional catalysts for dimethyl ether synthesis from CO_(2)hydrogenation

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Chinese Journal of Chemical Engineering 2021年第10期34卷 106-113页

作者： xiao Fan Shoujie Ren Baitang jin Shiguang Li Miao Yu Xinhua liang Department of Chemical and Biochemical Engineering Missouri University of Science and TechnologyRollaMO 65409United States Gas Technology Institute 1700 South Mount Prospect RoadDes PlainesIL 60018United States Department of Chemical and Biological Engineering Rensselaer Polytechnic InstituteTroyNY 12180United States

A series of iron(Fe)modified CuO-ZnO-ZrO_(2)-Al_(2)O_(3)(CZZA)catalysts,with various Fe loadings,were prepared using a co-precipitation method.A bifunctional catalyst,consisting of Fe-modified CZZA and HZSM-5,was studied for dimethyl ether(DME)synthesis via CO_(2)*** effects of Fe loading,reaction temperature,reaction pressure,space velocity,and concentrations of precursor for the synthesis of the Fe-modified CZZA catalyst on the catalytic activity of DME synthesis were ***-term stability tests showed that Fe modification of the CZZA catalyst improved the catalyst stability for DME synthesis via CO_(2)*** activity loss,in terms of DME yield,was significantly reduced from 4.2%to 1.4%in a 100 h run of reaction,when the Fe loading amount was 0.5(molar ratio of Fe to Cu).An analysis of hydrogen temperature programmed reduction revealed that the introduction of Fe improved the reducibility of the catalysts,due to assisted adsorption of H2 on iron *** good stability of Femodified CZZA catalysts in the DME formation was most likely attributed to oxygen spillover that was introduced by the addition of iron *** could have inhibited the oxidation of the Cu surface and enhanced the thermal stability of copper during long-term reactions.

关键词： CO_(2)hydrogenation Cu-ZnO based catalyst Iron(Fe) Dimethyl ether(DME) Stability

不同土壤及水分对稳定型尿素硝酸铵溶液调控氮素的影响及其肥效研究

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核农学报 2025年第2期39卷 404-413页

作者：张迪杜连凤魏丹金梁丁建莉王磊董淑祺肖强北京市农林科学院植物营养与资源环境研究所北京100097

为验证稳定型尿素硝酸铵溶液(YUAN,脲酶、硝化抑制剂用量均占UAN的0.06%)在夏玉米栽培中的应用效果,采用室内培养与田间试验,探究不同土壤[褐土(S1)和红壤(S2)]、不同土壤田间持水量[40%(W1)、60%(W2)和80%(W3)]以及夏玉米种植条件下[... 详细信息

为验证稳定型尿素硝酸铵溶液(YUAN,脲酶、硝化抑制剂用量均占UAN的0.06%)在夏玉米栽培中的应用效果,采用室内培养与田间试验,探究不同土壤[褐土(S1)和红壤(S2)]、不同土壤田间持水量[40%(W1)、60%(W2)和80%(W3)]以及夏玉米种植条件下[不施氮(CK)、追施普通尿素(CN)、优化CN(CNU)、追施普通尿素硝酸铵溶液(UAN)、追施稳定型尿素硝酸铵溶液(UANa和UANb)],稳定型尿素硝酸铵溶液(YUAN)对其所含氮素的调控效果及肥效。结果表明,YUAN处理下,土壤铵态氮含量平均上升和下降速率均慢于UAN处理,铵态氮含量在下降期内显著高于UAN处理。铵态氮含量在S1中的平均上升速率(41.63 mg·kg^(-1)·d^(-1))和下降速率(25.50 mg·kg^(-1)·d^(-1))均大于在S2中的平均上升速率(35.79 mg·kg^(-1)·d^(-1))和下降速率(16.74 mg·kg^(-1)·d^(-1)),0~56 d内二者铵态氮含量整体达到显著差异,说明YUAN的氮素在S2中转化的慢,其对氮素的调控效果更佳。在W1、W2和W3土壤田间持水量条件下,0~91 d内YUAN处理铵态氮含量整体显著高于UAN处理,土壤硝态氮含量峰值出现的时间分别为7、91和21 d(分别为933.70、1128.80和1507.10 mg·kg^(-1)),说明W2田间持水量条件下YUAN调控氮素的效果较优。与CN相比,UANa处理玉米产量提升690 kg·hm^(-2),增产率为8.73%,氨挥发减少67.10%。与UAN相比,UANa处理玉米产量提升779 kg·hm^(-2),增产率为9.97%,氨挥发减少60.64%。在0~20 cm土层内,硝态氮含量以CN和UANa处理较高,二者之间差异不显著,但显著高于其他处理,其他处理之间差异不显著;在180~200 cm土层内,施肥处理中以UANa处理硝态氮含量最低,分别较CN、CNU、UAN和UANb处理降低46.60%、26.08%、40.59%和27.07%,其中UANa处理显著低于CN和UAN处理。本研究结果为稳定型尿素硝酸铵溶液氮肥的推广应用奠定了理论基础与技术支撑。

关键词：尿素硝酸铵溶液土壤酸碱土壤水分抑制剂夏玉米

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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue Zhou jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel

长期血透患者并发腕管综合征应用高通量透析的护理

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实用护理杂志 2002年第5期18卷 7-8页

作者：夏友雯杨金芳张晓良石正娣黄平徐立东南大学附属中大医院江苏南京210009

目的　本研究旨在观察长期血透患者并发腕管综合征应用高通量透析 (HFD)的疗效并总结护理体会。方法　长期血透并发腕管综合征的患者 ,用聚砜膜F6 0高通量透析器进行血液透析 8个月 ,透析过程中检测F6 0血滤器第 1、7、12次复用透析前后... 详细信息

目的　本研究旨在观察长期血透患者并发腕管综合征应用高通量透析 (HFD)的疗效并总结护理体会。方法　长期血透并发腕管综合征的患者 ,用聚砜膜F6 0高通量透析器进行血液透析 8个月 ,透析过程中检测F6 0血滤器第 1、7、12次复用透析前后BUN、β2 -MG的指标。观察腕关节疼痛改善情况。结果　HFD透析器第 1、7、12次复用透析后β2 -MG、BUN水平均较透析前明显下降 ;病人的腕关节疼痛程度明显减轻。透析中少数病例出现低血压、抽搐等不良反应。结论　HFD可以显著清除 β2 -MG ,显著改善关节疼痛程度 ;透析器复用 12次不影响对小分子毒素的清除效果。

关键词：高通量透析腕管综合征护理

AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis

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Neural Regeneration Research 2025年第8期20卷 2408-2419页

作者： Ruiqi Qiu Mingzhu Yang Xiuxiu jin jingyang Liu Weiping Wang xiaoli Zhang jinfeng Han Bo Lei Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Eye Institute Henan Academy of Innovations in Medical ScienceZhengzhouHenan ProvinceChina Branch of National Clinical Research Center for Ocular Disease Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Academy of Medical Science Zhengzhou UniversityZhengzhouHenan ProvinceChina

Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell ***,there is no effective treatment for retinitis pigmentosa caused by PDE6B ***-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis *** aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal *** do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and ***-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western ***2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 *** expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type *** Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction ***,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B ***,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B *** data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upr

关键词： apoptosis AAV2-PDE6B ERK1/2 gene therapy phototransduction proteomics rd10 retinitis pigmentosa

Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： Tian Qin Yuxin jin Yiming Qin Feifei Yuan Hongbin Lu Jianzhong Hu Yong Cao Chengjun Li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2

MOLECULAR WEIGHT DEPENDENCE OF CRYSTAL PATTERN TRANSITIONS OF POLY(ETHYLENE OXIDE)

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Chinese Journal of Polymer Science 2013年第5期31卷 798-808页

作者： Guo-liang Zhang Liu-xin jin Ping Zheng 王维 xiao-jing Wen Center for Synthetic Soft Materials The Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer ChemistryCollege of ChemistryNankai University School of Resources and Materials Northeastern University at Qinhuangdao

Crystal patterns in ultrathin films of six poly（ethylene oxide） fractions with molecular weights from 25000 to 932000 g/mol were characterized within crystallization temperature range from 20 ℃to 60℃. Labyrinthine, dendritic and faceted crystal patterns were observed in different temperature ranges, and then labyrinthine-to-dendritic and dendritic-to- faceted transition temperatures T_L-D and T_D-F were quantitatively identified. Their molecular weight dependences are T_L-D（M_w） = T_L-D（∞） -K_L-D/M_w, where T_L-D（∞） = 38.2 ℃ and K_L-D = 253000 ℃.g/mol and T_D-F（M_w） = T_D-F（∞） -K_D-F/M_w, where T_D-F（∞） = 54.7 ℃ and K_D-F= 27000 ℃.g/mol. Quasi two-dimensional blob models were proposed to provide empirical explanations of the molecular weight dependences. The labyrinthine-to-dendritic transition is attributed to a molecular diffusion process change from a local-diffusion to diffusion-limited-aggregation （DLA） and a polymer chain with M_w ≈253000 g/mol within a blob can join crystals independently. The dendritic-to-faceted transition is attributed to a turnover of the pattern formation mechanism from DLA to crystallization control, and a polymer chain with a M_w ≈27000 g/tool as an independent blob crosses to a depletion zone to join crystals. These molecular weight dependences reveal a macromolecular effect on the crystal pattern formation and selection of crystalline polymers.

关键词： Poly(ethylene oxide) Crystallization Pattern formation Transition Molecular weight dependence.

NMR Studies of a New Binding Mode of the Amino Acid Esters by Porphyrinatozinc(Ⅱ)

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Chemical Research in Chinese Universities 2001年第1期17卷 1-5页

作者： PENG xiao-bin HUANG jin-wang LI Tao JI liang-nian Department of Chemistry Zhongshan UniversityGuangzhou 510275P.R.China

The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between the amino group of the guest and the carboxyl group of host 1 plus the coordination between the zinc atom of porphyrinatozinc(Ⅱ) and the carbonyl group of the guest. This is a novel binding mode of the metalloporphyrin to amino acid derivatives.

关键词： H NMR Porphyrinatozinc(Ⅱ) Amino acid ester New binding mode