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A Hierarchical Short Microneedle-Cupping Dual-Amplified Patch Enables Accelerated,Uniform,Pain-Free Transdermal Delivery of Extracellular Vesicles
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作者 Minwoo Song Minji Ha +8 位作者 Sol Shin Minjin Kim Soyoung Son Jihyun Lee Gui Won Hwang Jeongyun Kim Van Hieu Duong Jae Hyung Park Changhyun Pang 《Nano-Micro Letters》 2026年第1期268-289,共22页
Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,con... Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,conventional MNs employ long needles(≥600μm),leading to pain and skin irritation.Moreover,it is critical to stably apply MNs against complex skin surfaces for uniform nanoscale drug delivery.Herein,a dually amplified transdermal patch(MN@EV/SC)is developed as the stem cell-derived EV delivery platform by hierarchically integrating an octopusinspired suction cup(SC)with short MNs(≤300μm).While leveraging the suction effect to induce nanoscale deformation of the stratum corneum,MN@EV/SC minimizes skin damage and enhances the adhesion of MNs,allowing EV to penetrate deeper into the dermis.When MNs of various lengths are applied to mouse skin,the short MNs can elicit comparable corticosterone release to chemical adhesives,whereas long MNs induce a prompt stress response.MN@EV/SC can achieve a remarkable penetration depth(290μm)for EV,compared to that of MN alone(111μm).Consequently,MN@EV/SC facilitates the revitalization of fibroblasts and enhances collagen synthesis in middle-aged mice.Overall,MN@EV/SC exhibits the potential for skin regeneration by modulating the dermal microenvironment and ensuring patient comfort. 展开更多
关键词 Biomimetics CUPPING MICRONEEDLE Transdermal patch Extracellular vesicles
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Patching the cracks of catalyst layer for stable alkaline saline water electrolysis
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作者 Si-Hua Lin Jin He +2 位作者 Zi-Qi Tian Xiao-Peng Qi Yi-Chao Lin 《Rare Metals》 2025年第9期6760-6770,共11页
Using abundant saline water for electrolysis,rather than limited freshwater,presents a promising technique for generating clean hydrogen energy.However,high concentration of corrosive chloride ions in saline water pos... Using abundant saline water for electrolysis,rather than limited freshwater,presents a promising technique for generating clean hydrogen energy.However,high concentration of corrosive chloride ions in saline water poses a great challenge in the stability of anode.In this study,we present a straightforward strategy to protect the anode from corrosion by patching the catalyst layer through a treatment of the anode with a sodium sulfide(Na2S) solution followed by electrochemical activation.The rapid sulfurization of the Ni electrode in Na2S results in the formation of a Na2S layer,which can subsequently be converted to NiOOH upon electrochemical activation,thereby shielding the inner Ni electrode from corrosion.The as-prepared electrode (P-NiFe-LDH/Ni) based on the strategy demonstrated stability over 3,500 h at an industrial current density of 0.5 A cm^(-2)in a 0.5 M NaCl and 1 M KOH solution.This study presents an effective strategy to significantly enhance the stability of anodes for saline water electrolysis by effectively patching the cracks in the catalyst layer. 展开更多
关键词 NiFe-LDH patch Stability Saline electrolysis Corrosion
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Gold Nanoparticle-Incorporated Polyurethane/Collagen Nanofibrous Scaffold as a Potential Cardiac Patch
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作者 Hadiyeh Mozaffari Parisa Javadi +1 位作者 Reza Faridi-Majidi Mohammad Ali Derakhshan 《Journal of Bionic Engineering》 2025年第4期1910-1925,共16页
Due to the limited regeneration capacity of myocardial tissue after infarction,designing tissue engineering scaffolds are in demand.In the present study,electrospun nanofibrous scaffolds were made out of polyurethane,... Due to the limited regeneration capacity of myocardial tissue after infarction,designing tissue engineering scaffolds are in demand.In the present study,electrospun nanofibrous scaffolds were made out of polyurethane,collagen and gold nanoparticles with random and aligned nanofiber morphologies.The nanoparticles were green-synthesized using saffron extract.Nanoparticle characterizations with UV-Vis.spectroscopy and DLS illustrated theoretical and hydrodynamic diameters of around 7 and 13 nm,respectively,having zeta potential of−37 mV.SEM and TEM micrographs showed the morphology and diameters of obtained nanofibers.Also,further characterization were done by ATR-FTIR,XRD and TGA investigations and degradation studies.Contact angle measurements showed hydrophilic nature of the scaffolds(59±0.6°for aligned PU/Col/Au50 nanofibers compared to 120±2.6°for random PU nanofibers).Mechanical testing demonstrated appropriate tensile properties of the scaffolds for cardiac tissue engineering(Young’s modulus:1.53±0.07 MPa for aligned PU/Col/Au50 nanofibers compared to 0.4±0.05 MPa for random PU nanofibers).Finally,alamar blue assay revealed proper survival of the cells of HUVEC cell line on the prepared scaffolds,where the highest percentages were observed for random and aligned PU/Col/Au50 nanofibers.According to the findings,the fabricated PU/Col/AuNPs nanofibrous scaffolds could be considered as potential cardiac patches. 展开更多
关键词 Electrospun nanofiber POLYURETHANE COLLAGEN Gold nanoparticles Cardiac patch
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Multi-Phase Modeling for Vulnerability Detection & Patch Management: An Analysis Using Numerical Methods
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作者 Adarsh Anand Div ya +1 位作者 Deepti Aggrawal Omar H.Alhazmi 《Computers, Materials & Continua》 2025年第7期1529-1544,共16页
Software systems are vulnerable to security breaches as they expand in complexity and functionality.The confidentiality,integrity,and availability of data are gravely threatened by flaws in a system’s design,implemen... Software systems are vulnerable to security breaches as they expand in complexity and functionality.The confidentiality,integrity,and availability of data are gravely threatened by flaws in a system’s design,implementation,or configuration.To guarantee the durability&robustness of the software,vulnerability identification and fixation have become crucial areas of focus for developers,cybersecurity experts and industries.This paper presents a thorough multi-phase mathematical model for efficient patch management and vulnerability detection.To uniquely model these processes,the model incorporated the notion of the learning phenomenon in describing vulnerability fixation using a logistic learning function.Furthermore,the authors have used numerical methods to approximate the solution of the proposed framework where an analytical solution is difficult to attain.The suggested systematic architecture has been demonstrated through statistical analysis using patch datasets,which offers a solid basis for the research conclusions.According to computational research,learning dynamics improves security response and results in more effective vulnerability management.The suggested model offers a systematic approach to proactive vulnerability mitigation and has important uses in risk assessment,software maintenance,and cybersecurity.This study helps create more robust software systems by increasing patch management effectiveness,which benefits developers,cybersecurity experts,and sectors looking to reduce security threats in a growing digital world. 展开更多
关键词 Learning phenomenon numerical method patchING two-phase modelling VULNERABILITY
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CNN-based multi-output regression model to estimate infrastructural surface crack dimensions adopting a generalised patch size and FWHM-based width quantification
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作者 Sudipta Debroy Arjun Sil 《Digital Twins and Applications》 2025年第1期75-102,共28页
To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks o... To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks obtained from a public dataset are cropped into patches of 256 square pixels that are classified with a pre-trained deep convolution neural network,the true positives are segmented,and crack properties are extracted using two different methods.The first method is primarily based on active contour models and level-set segmentation and the second method consists of the domain adaptation of a mathematical morphology-based method known as FIL-FINDER.A statistical test has been performed for the comparison of the stated methods and a database prepared with the more suitable method.An advanced convolution neural network-based multi-output regression model has been proposed which was trained with the prepared database and validated with the held-out dataset for the prediction of crack-length,crack-width,and width-uncertainty directly from input image patches.The pro-posed model has been tested on crack patches collected from different locations.Huber loss has been used to ensure the robustness of the proposed model selected from a set of 288 different variations of it.Additionally,an ablation study has been conducted on the top 3 models that demonstrated the influence of each network component on the pre-diction results.Finally,the best performing model HHc-X among the top 3 has been proposed that predicted crack properties which are in close agreement to the ground truths in the test data. 展开更多
关键词 ablation CNN convolution neural network CRACK crack patch estimation FWHM length multi-output regression segmentation uncertainty WIDTH
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A statistical survey of polar cap cold and hot patches in the Southern Hemisphere using a DMSP Satellite
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作者 Duan Zhang QingHe Zhang +11 位作者 Kjellmar Oksavik ZanYang Xing LRLyons HuiGen Yang Tong Xu Marc Hairston XiangYu Wang YuZhang Ma GuoJun Li Yong Wang Sheng Lu Jin Wang 《Earth and Planetary Physics》 2025年第4期955-965,共11页
This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were ide... This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were identified by Defense Meteorological Satellite Program(DMSP)F16 during the years 2011 to 2022.A temperature ratio of ion/electron temperature(T_(i)/T_(e))<0.68 is recommended to define a hot patch in the Southern Hemisphere,otherwise it is defined as a cold patch.The cold and hot patches have different dependencies on IMF clock angle,while their dependencies on IMF cone angle are similar.Both cold and hot patches appear most often on the duskside,and the distribution of cold patches gradually decreases from the dayside to the nightside,while hot patches have a higher occurrence rate near 14 and 21 magnetic local time(MLT).Moreover,we compared the key plasma characteristics of polar cap cold and hot patches in the Southern and Northern Hemispheres.The intensity of the duskside upward field-aligned current of patches in the Southern Hemisphere(SH)is stronger than that in the Northern Hemisphere(SH),which may be due to the discrepancy in conductivities between the two hemispheres,caused by the tilted dipole.In both hemispheres,the downward soft-electron energy flux of the dawnside patches is significantly greater than that of the duskside patches. 展开更多
关键词 polar ionosphere polar cap patch IRREGULARITIES statistical survey southern hemisphere.
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PPFormer:Patch Prototype Transformer for Semantic Segmentation
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作者 Shanyuan Liu Yonggang Lu 《Journal of Beijing Institute of Technology》 2025年第4期405-417,共13页
Since the introduction of vision Transformers into the computer vision field,many vision tasks such as semantic segmentation tasks,have undergone radical changes.Although Transformer enhances the correlation of each l... Since the introduction of vision Transformers into the computer vision field,many vision tasks such as semantic segmentation tasks,have undergone radical changes.Although Transformer enhances the correlation of each local feature of an image object in the hidden space through the attention mechanism,it is difficult for a segmentation head to accomplish the mask prediction for dense embedding of multi-category and multi-local features.We present patch prototype vision Transformer(PPFormer),a Transformer architecture for semantic segmentation based on knowledge-embedded patch prototypes.1)The hierarchical Transformer encoder can generate multi-scale and multi-layered patch features including seamless patch projection to obtain information of multiscale patches,and feature-clustered self-attention to enhance the interplay of multi-layered visual information with implicit position encodes.2)PPFormer utilizes a non-parametric prototype decoder to extract region observations which represent significant parts of the objects by unlearnable patch prototypes and then calculate similarity between patch prototypes and pixel embeddings.The proposed contrasting patch prototype alignment module,which uses new patch prototypes to update prototype bank,effectively maintains class boundaries for prototypes.For different application scenarios,we have launched PPFormer-S,PPFormer-M and PPFormer-L by expanding the scale.Experimental results demonstrate that PPFormer can outperform fully convolutional networks(FCN)-and attention-based semantic segmentation models on the PASCAL VOC 2012,ADE20k,and Cityscapes datasets. 展开更多
关键词 hierarchical backbones patch prototype nonparametric learning semantic segmentation
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A magnetic patch robot with photothermal-activated multi-modality for targeted anti-postoperative adhesion
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作者 Tanyong Wei Yang Hu +2 位作者 Ming Yang Chaoyang Shi Chengzhi Hu 《International Journal of Extreme Manufacturing》 2025年第5期388-402,共15页
Adhesive patches offer an effective approach for wound closure,making them highly suitable for biomedical applications.However,conventional patches often face limitations such as dual-sided adhesion,lack of shape adap... Adhesive patches offer an effective approach for wound closure,making them highly suitable for biomedical applications.However,conventional patches often face limitations such as dual-sided adhesion,lack of shape adaptability,and limited maneuverability,which restrict their applications in deeper tissues.In this paper,we develop a magnetic patch robot(PatchBot),for targeted Janus adhesion with tissues.The PatchBot features a unique triple-layer structure,with adhesive,shape-morphing,and anti-adhesive layers,each fulfilling roles to support targeted attachment,enable shape transformation,and prevent unwanted adhesion to surrounding tissues.The Janus adhesion of the PatchBot was extensively demonstrated across a variety of tissues.A localized near-infrared(NIR)laser irradiation was used to induce programmable shape transformations.Magnetic actuation of the PatchBot for targeted adhesion was successfully demonstrated in ex vivo porcine stomach tissue.NIR light-activated shape-morphing and multimodal magnetic actuation significantly enhance its maneuverability and adaptability in confined in vivo environments while ensuring the structural integrity of the adhesive surface during deployment.This proof-of-concept study demonstrates the feasibility of using PatchBot for targeted wound adhesion,showing its potential for minimally invasive,precision therapies in complex in vivo environments. 展开更多
关键词 miniature magnetic robot multimodal locomotion adhesive patch biomedical applications
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Effects of Childlike Nursing Combined with Chinese Herbal Patching on Pediatric Bronchopneumonia and Symptom Recovery Time
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作者 Jiejing Xu Qingya Li 《Journal of Clinical and Nursing Research》 2025年第7期236-242,共7页
Objective:To evaluate the intervention effect of childlike nursing combined with Chinese herbal patching on pediatric bronchopneumonia.Methods:1036 children with bronchopneumonia(one family member included for each ch... Objective:To evaluate the intervention effect of childlike nursing combined with Chinese herbal patching on pediatric bronchopneumonia.Methods:1036 children with bronchopneumonia(one family member included for each child)who were admitted to the hospital between January 2024 and June 2024 were selected and randomly divided into two groups using a random number table.The combined group received childlike nursing combined with Chinese herbal patching,while the control group received routine nursing.Symptom recovery time,treatment compliance,inflammatory factor levels,quality of life of the children,and family satisfaction were compared between the two groups.Results:The symptom recovery time in the combined group was shorter than that in the control group,treatment compliance was higher,inflammatory factor levels after intervention were lower,quality of life scores of the children were lower,and family satisfaction was higher(P<0.05).Conclusion:The implementation of childlike nursing combined with Chinese herbal patching for children with bronchopneumonia can shorten their symptom recovery time,significantly improve treatment compliance and quality of life,reduce inflammatory reactions,and achieve high satisfaction among family members. 展开更多
关键词 Childlike nursing Chinese herbal patching Pediatric bronchopneumonia Symptom recovery time
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Thermo-responsive microneedles patch for transdermal drug delivery via squeezing in diabetic foot ulcers
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作者 Xiaotong Wu Dan Xia +4 位作者 Tingting Shi Baoe Li Donghui Wang Chunyong Liang Mingdong Dong 《Journal of Materials Science & Technology》 2025年第2期299-314,共16页
Microneedle(MN)patches could be a promising treatment for diabetic foot ulcers that plague thousands of people worldwide.While reducing skin resistance or increasing driving force can accelerate the efficiency of tran... Microneedle(MN)patches could be a promising treatment for diabetic foot ulcers that plague thousands of people worldwide.While reducing skin resistance or increasing driving force can accelerate the efficiency of transdermal drug delivery with conventional MN patches,it can create toxic chemical residues or require the help of additional devices.Herein,a thermo-responsive microneedles patch(TMN)with high biocompatibility without additional equipment is proposed.The TMN consisted of a bilayer microneedles composed of sodium alginate(SA)-g-poly(N-isopropylacrylamide)layer(SA-g-PNIPAM)loaded with sucrose octasulfate sodium salt(SOS)and hyaluronic acid layer and a polycaprolactone/chitosan nanofiber membrane loading with tetracycline hydrochloride(TH)and SOS.PNIPAM accelerates drug release by extruding the drug through a volumetric phase transition in response to temperature changes,and TH and SOS promote wound healing by inhibiting bacterial growth and promoting vascular regeneration and epithelial formation.The results showed that the drug release of TMN was significantly faster,with the drug release rate of more than 80% in the 10th h,and the antibacterial rate of TMN could reach 800%.In addition,TMN had good biocompatibility and good healing effects in vivo,which may be helpful for the design of multifunctional dressings in the future. 展开更多
关键词 Microneedles patch Thermal response Transdermal drug delivery Diabetic foot ulcers
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A microneedle substrate-based sutureless engineered cardiac patch for myocardial infarction repair
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作者 Zibo Liu Pengcheng Yang +7 位作者 Yueming Tian Heyuan Deng Jingjing Xia Binhan Li Bingyan Wu Yongcong Fang Zhuo Xiong Ting Zhang 《Bio-Design and Manufacturing》 2025年第6期917-929,I0001-I0003,共16页
Myocardial infarction(MI)is a challenging condition that results in scar formation on the ventricular wall,causing myocardial damage and ventricular thinning.Engineered cardiac patches(ECPs)designed to regenerate myoc... Myocardial infarction(MI)is a challenging condition that results in scar formation on the ventricular wall,causing myocardial damage and ventricular thinning.Engineered cardiac patches(ECPs)designed to regenerate myocardial tissue have been proposed to repair the ventricular wall and replenish myocardial cells.However,their clinical use is limited by manufacturing and fixation challenges.This study introduces a manufacturing strategy for a composite ECP,which comprises an antiadhesion shell layer,a conductive myocardial tissue,and an exosome-laden microneedle substrate.The ECP can anchor to the infarcted myocardium through its microneedle substrate.Meanwhile,its outer shell prevents nonspecific adhesion,enabling stable and suture-free attachment.Using this microneedle substrate,we applied a 3D-printed ECP in a rat model of post-MI repair.Our results showed that this strategy reduced left ventricular damage,improved cardiac ejection fraction,decreased the fibrotic area,increased ventricular wall thickness,improved microvascular recovery,and thus facilitated the repair of maladaptive ventricular remodeling post-MI.This microneedle substrate holds great promise for use in the fixation of patches during the repair of myocardial tissue and other organs,thereby promoting the clinical application of tissue-engineered patches. 展开更多
关键词 MICRONEEDLES Engineered cardiac patches Myocardial infarction repair
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基于自适应Patching的船舶轨迹预测模型
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作者 张爽 《信息产业报道》 2025年第10期0038-0040,共3页
船舶航迹预测对于航行安全、导航优化以及港口调度具有关键作用。针对传统 Transformer 模型在捕捉船舶轨迹长程依赖关系方面存在的不足,文章提出一种基于自适应 Patch 划分的 Transformer 模型。该方法通过引入可学习的自适应 Patch 机... 船舶航迹预测对于航行安全、导航优化以及港口调度具有关键作用。针对传统 Transformer 模型在捕捉船舶轨迹长程依赖关系方面存在的不足,文章提出一种基于自适应 Patch 划分的 Transformer 模型。该方法通过引入可学习的自适应 Patch 机制,将船舶历史轨迹智能地划分为具有动态长度的子序列,有效降低了 Transformer 注意力机制的计算复杂度,并使模型更灵活地捕获长时间范围内轨迹数据的动态变化和潜在依赖关系。实验结果表明,该方法显著提升了船舶轨迹预测的精度与计算效率,为智能航运管理和港口物流优化提供了高效、准确的决策支持工具。 展开更多
关键词 船舶航迹预测 自适应 patch Transformer 模型
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利用GPS对磁暴期间极区TEC变化与极区碎片(Polar Patches)的研究 被引量:13
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作者 孟泱 王泽民 +1 位作者 鄂栋臣 蔡红涛 《地球物理学报》 SCIE EI CSCD 北大核心 2008年第1期17-24,共8页
利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分... 利用2004年11月6-10日磁暴发生期间南极区域内的中国中山站GPS常年跟踪站(ZHON)和国际GPS服务站(CAS1,MCM4,SYOG,MAW1)的GPS观测数据,计算了可观测卫星传播路径上的TEC和ROT值,进而依据TEC的波动频率和幅度推估出极区碎片的个数,分析了极区磁暴期间电离层响应及其极区碎片特性.最终所得TEC和ROT结果与极区地磁场Dst和Kp指数信息相吻合,如实地反映了磁暴事件和极区碎片的出现.本文所做工作在国内尚未开展,因此所用方法和结论为将来这一方向的研究提供了一定的参考. 展开更多
关键词 磁暴 极区碎片(polar patches) GPS TEC ROT
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基于支持向量回归的patch近场声全息研究 被引量:11
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作者 杜向华 朱海潮 +1 位作者 毛荣富 朱海鹏 《声学学报》 EI CSCD 北大核心 2012年第3期286-293,共8页
为了解决patch近场声全息中全息数据外推问题,提出一种基于支持向量回归的一步式patch近场声全息技术。该方法首先把初始全息面上的数据当成训练样本进行学习,构造出回归函数,然后利用回归函数实现全息数据外推,最后基于统计最优近场声... 为了解决patch近场声全息中全息数据外推问题,提出一种基于支持向量回归的一步式patch近场声全息技术。该方法首先把初始全息面上的数据当成训练样本进行学习,构造出回归函数,然后利用回归函数实现全息数据外推,最后基于统计最优近场声全息进行重建。数值仿真和实验研究的结果表明:在各个分析频率下,该方法都可以实现小孔径全息面的近场外推。从近场声全息重建结果看,即使初始全息数据受到噪声干扰,该方法也是一种有效的patch近场声全息技术。 展开更多
关键词 近场声全息 patch 支持向量回归 声全息技术 数据外推 回归函数 训练样本 数值仿真
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基于Patch Analyst的北京城市公园景观格局指数评价 被引量:14
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作者 谢军飞 李炜民 +3 位作者 李延明 郭佳 李薇 卜燕华 《城市环境与城市生态》 CAS CSCD 2007年第6期14-16,19,共4页
为了解2003年北京城市公园绿地景观格局的构成和特征,在地理信息系统的支持下,选取了景观破碎度、最近邻点指数、平均斑块分维指数与格网分析等方法,通过Patch Analyst软件对北京城八区内的公园进行了分析。其结果表明,城八区内的公园... 为了解2003年北京城市公园绿地景观格局的构成和特征,在地理信息系统的支持下,选取了景观破碎度、最近邻点指数、平均斑块分维指数与格网分析等方法,通过Patch Analyst软件对北京城八区内的公园进行了分析。其结果表明,城八区内的公园总面积较大,达到了4 380 hm2,最近邻点指数R为1.97,斑块总体趋于均匀分布,整体景观破碎度为2.65,东城区斑块的边界形状较为复杂。值得注意的是,北京西南区域公园数量和面积都较少,应适当加强其区域公园建设。 展开更多
关键词 公园 景观格局 patchAnalyst 北京
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大鼠纹状体Patch和Matrix间区及其神经元形态学特征的观察 被引量:2
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作者 雷万龙 刘冰冰 +2 位作者 穆淑花 李可一 朱亚西 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2009年第2期121-125,136,共6页
【目的】纹状体Patch和Matrix间区被证实与神经精神活动和躯体运动有关。本实验旨在探测Patch和Matrix间区及其神经元的形态学特征,为研究纹状体-Patch和-Matrix神经元的通路联系提供资料。【方法】成年雄性SD大鼠分别按照常规和电镜要... 【目的】纹状体Patch和Matrix间区被证实与神经精神活动和躯体运动有关。本实验旨在探测Patch和Matrix间区及其神经元的形态学特征,为研究纹状体-Patch和-Matrix神经元的通路联系提供资料。【方法】成年雄性SD大鼠分别按照常规和电镜要求灌注固定、取脑和后固定;半导体或振动切片之后进行免疫组化PAP方法单标记和双标记;光镜下分别用Photoshop软件测量Patch和Matrix间区的面积并计算百分比;光镜和电镜下观察阳性神经元的结构;实验数据用SPSS软件统计处理。【结果】①Mor阳性的Patch间区呈不规则形的斑块状散在分布于纹状体,在胼胝体深方存在一条恒定的阳性带状区。Patch间区占纹状体面积的9%,其面积在纹状体的头侧明显大于尾侧(P<0.05)。阳性结构呈细丝或絮状,阳性胞体不明显。②Calb阳性的Matrix间区在纹状体内侧区染色较深,可见明显不规则的淡染色区,其形状与相邻片的Patch间区一致。Matrix间区的面积明显大于Patch间区(P<0.05)。可见阳性树突和树突棘,但阳性胞体不明显。③电镜下分别可见Mor和Calb阳性树突和树突棘,其大多数接受兴奋性突触连接,而与阳性树突形成的突触多为穿孔型。抑制性突触少见,阳性胞体不明显。【结论】头侧纹状体密集分布的Patch间区、内侧纹状体Calb强烈反应,和阳性标记的树突、树突棘以及兴奋性突触为主的形态学特征,提示Mor和Calb阳性神经元分别具有特异性的神经通路连接和生理机能。 展开更多
关键词 纹状体 patch间区 Matrix间区 MOR CALB
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弓形虫复合粘膜疫苗滴鼻免疫小鼠诱导的Peyer's patches持续性细胞免疫应答 被引量:2
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作者 孟晓丽 殷国荣 +3 位作者 张建红 刘红丽 申金雁 李珀 《中国病原生物学杂志》 CSCD 2008年第1期27-30,共4页
目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法B... 目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法BALB/c小鼠96只,随机分为实验组和对照组,实验组以STAg(20μg/只)为抗原,CT(1/μg/只)为佐剂滴鼻免疫,对照组PBS滴鼻。滴鼻2次(间隔2周)后,每组6只小鼠分别于第1、2、3、4、6、8、10、12周处死。计数PP个数,制备PP淋巴细胞悬液,计数并涂片;免疫细胞化学法检测CD4^+、CD8^+T细胞亚群。结果实验期间两组小鼠PP数目均无明显变化;实验组免疫后PP淋巴细胞数量明显增生,第2周达高峰,第1、2、3周显著高于对照组(P〈0.05),其中以CD4^+T细胞增生为主,第1周~第8周高于对照组(P〈0.01),CD8^+T细胞第1周~第4周显著增高(P〈0.01),CD4^+/CD8^+比值无显著变化(P〉0.05)。结论弓形虫复合粘膜疫苗滴鼻免疫BALB/c小鼠可有效诱导肠PP部位持续性的免疫应答,从而激活肠粘膜效应部位淋巴细胞的抗弓形虫感染作用。 展开更多
关键词 弓形虫 粘膜疫苗 滴鼻免疫 可溶性速殖子抗原 霍乱毒素 Peyer’s patchES
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视频流点播Dynamic Batched Patching算法研究 被引量:3
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作者 周建政 蒋建国 +1 位作者 韩江洪 齐美彬 《电子学报》 EI CAS CSCD 北大核心 2004年第3期452-456,共5页
本文提出了一个新的视频流点播传输策略 ,用以解决现有传输策略中存在的系统资源利用率低 ,QoS较差等问题 .该策略的思想是服务器根据用户请求到达时刻 ,按动态批处理的方式来接纳并服务请求用户 ,每组用户必须同时从一个或两个信道接... 本文提出了一个新的视频流点播传输策略 ,用以解决现有传输策略中存在的系统资源利用率低 ,QoS较差等问题 .该策略的思想是服务器根据用户请求到达时刻 ,按动态批处理的方式来接纳并服务请求用户 ,每组用户必须同时从一个或两个信道接收视频内容 .文中对本策略的性能进行了理论推导与定量分析 ,并与现有传输策略作了性能比较 ,最后采用仿真实验对前面的理论分析与比较进行了验证 .理论分析及实验结果表明该策略是一个简单高效的传输策略 。 展开更多
关键词 VOD 视频流 传输机制 DYNAMIC Batched patching算法 传输策略 视频流点播系统
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基于Patch-Dynamics模式的土地覆被变化预测——以北京市为例 被引量:13
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作者 谢正磊 许学工 孙强 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第3期452-458,共7页
利用北京市土地利用变化数据建立了Patch-dynamics动力模型。模拟结果表明了在不同的时间尺度上耕地所占比例都持续下降,城镇建设用地、林地所占比例继续上升。由于该模式考虑了模拟对象的变化过程以及不同土地利用类型之间的相互影响,... 利用北京市土地利用变化数据建立了Patch-dynamics动力模型。模拟结果表明了在不同的时间尺度上耕地所占比例都持续下降,城镇建设用地、林地所占比例继续上升。由于该模式考虑了模拟对象的变化过程以及不同土地利用类型之间的相互影响,其模拟结果比一般的简单动力模型模拟效果好。通过与实际情况的比较检验,用1996年数据对2001年的模拟结果与实际差别不大,误差在0~0.05之间,对于面积较小地类的模拟误差较小,说明这个方法可以用来对未来的土地利用变化状况进行模拟、预测。然而,这个模型只适应于十年尺度的预测,模拟时间越长,误差越大。在此基础上,提出协调土地利用矛盾,维持一定规模的城市绿色空间,实现首都城市定位目标的建议。 展开更多
关键词 土地覆被变化 动力学机制 patch-dynamics模型 北京市
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Static Force Reliability Analysis of Truss Structure with Piezoelectric Patches Affixed to Its Surface 被引量:3
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作者 安海 安伟光 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第1期22-31,共10页
For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consid... For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consideration,the finite element model for static force analysis is established by using the theory of mechanics. The failure mechanism of piezoelectric elements is discussed and the failure criteria of piezoelectric elements are proposed. The expression of safety margins for the element of piezoelec... 展开更多
关键词 piezoelectric truss structure piezoelectric patch mechanical-electric coupling safety margin stochastic finite element method structural reliability theory
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