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Removal of Stripes in Remote Sensing Images Based on Statistics Combined with Image Enhancement

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Journal of Geodesy and Geoinformation Science 2023年第1期6卷 76-87页

作者： Xiaofei QU Weiwei ZHAO En long Meng SUN Guangling lai Beijing Institute of Remote Sensing Information Beijing 100085China Army EngineeringUniversity of PLA Nanjing 210007China

A method to remove stripes from remote sensing images is proposed based on statistics and a new image enhancement *** overall processing steps for improving the quality of remote sensing images are introduced to provide a general *** to the differences in satellite sensors when producing images,subtle but inherent stripes can appear at the stitching positions between the *** stitchingstripes cannot be eliminated by conventional relative radiometric *** inherent stitching stripes cause difficulties in downstream tasks such as the segmentation,classification and interpretation of remote sensing ***,a method to remove the stripes based on statistics and a new image enhancement approach are proposed in this ***,the inconsistency in grayscales around stripes is eliminated with the statistical ***,the pixels within stripes are weighted and averaged based on updated pixel values to enhance the uniformity of the overall image radiation ***,the details of the images are highlighted by a new image enhancement method,which makes the whole image *** experiments are performed,and the results indicate that the proposed method outperforms the baseline approach in terms of visual quality and radiation correction accuracy.

关键词： remote sensing images stripe removal statistics image enhancement

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Microstructural evolution and mechanical properties of a new Al-Cu-Li-X alloy at different solution temperatures

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Rare Metals 2021年第3期40卷 635-642页

作者： long Zhang Zi-Qiao Zheng Jin-Feng Li Cheng-Yu Tan Yong-lai Chen Xu-Hu Zhang School of Materials Science and Engineering Central South UniversityChangsha 410083China Aerospace Research Institute of Materials and Processing Technology Beijing 100076China

The micros tructural evolution and mechanical properties of a new Al-3.8 Cu-1.2 Li-0.4 Mg-0.4 Zn-0.4 Ag-0.3 Mn-X alloy treated at different solution temperatures were *** grain size was measured in optical micrograph(OM).The residual particles and the major precipitates were identified by electron probe microanalysis(EPMA),scanning electron microscopy(SEM) and transmission electron microscope(TEM),*** results show that the peak strength appears at 530℃/1 h+T6(165℃/20 h) and the values are 566.2 MPa(tensile strength) and 538.2 MPa(yield strength) with the elongation of 6.5 %.The strength of the alloy increases rapidly with the amount of the precipitates T1 and θ’ increasing when the solution temperature is530℃.The increase in density of precipitates is resulted from the residual particles Al2 Cu,and particles enriched with Cu,Mg,Zr and Ag dissolve into matrix gradually with the solution temperature ***,the number of precipitates decreases and part of the grain boundary weakens with a further increase in solution temperature from 540 to 550℃,leading to a decline of strength.

关键词： Solution treatment Precipitates Microstructure Al-Cu-Li alloys

Regulating the d band in WS_(2)@NC hierarchical nanospheres for efficient lithium polysulfide conversion in lithium-sulfur batteries

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Journal of Energy Chemistry 2021年第5期30卷 343-352页

作者： Jintao Liu Shuhao Xiaoa Le Chang long lai Rui Wu Yong Xiang Xingquan Liu Jun Song Chen School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Center for Applied Chemistry University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina

The performance of lithium-sulfur batteries is deteriorated by the inferior conductivity of sulfur,the shuttle effect of lithium polysulfides(LiPSs),sluggish redox kinetics of polysulfide intermediates and serious volumetric expansion of *** overcome these challenges,we report a versatile route to prepare multi-functional nanocomposites with tuable hierarchical structure via ammonium hydroxide(NH_(3)·H_(2) O)induced *** versatility of the system has been demonstrated that the organization of the hierarchical structure can be regulated by adding different amounts of NH_(3)·H_(2) O,and WS_(2) and Co_(9)S_(8) with nitrogen-doped carbon coating(denoted as WS_(2)@NC and Co_(9)S_(8)@NC)can be prepared by adding different precursor *** the as-prepared materials are applied for Li-S batteries,the WS_(2)@NC composite exhibits a reversible capacity of 1107.4 mAh g^(-1) at 0.1 C after 500 cycles and even 728.9 mAh g^(-1) at2 C for 1000 cycles,which is significantly better than the Co_(9)S_(8) counterpart and other reported WS_(2) sulfur ***,the advantageous performance of WS_(2) could be attributed to its higher surface area and total pore volume,giving rise to the easier access to electrolyte and better ability to buffer the volume change during the charge/discharge ***,the density function theory(DFT)calculation reveals that the as-prepared WS_(2) has a higher binding energy towards LiPSs as well as a lower energy barrier for Li^(+)diffusion on the surface than Co_(9)S_(8).More significantly,the density of states(DOS)analysis further confirms that the superior performance is mainly ascribed to the more prominent shifting and the more charge compensation from d band of W than Co,which increase electronic concentration and give more hybridization of d-p orbitals in the Fermi level of the adsorbed Li2 S4 to accelerate the lithium polysulfide interfacial redox and conversion dynamics in WS_(2).By proposing this mechan

关键词： Dband regulation Density of states DFT theoretical calculations Metal sulfides Lithium-sulfur batteries

High-performance lens antenna using high refractive index metamaterials

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Chinese Physics B 2018年第8期27卷 559-565页

作者： lai-Jun Wang Qiao-Hong Chen Fa-long Yu Xi Gao School of Information and Communication Guilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory of Wireless Wideband Communication ＆ Signal Processing Guilin 541004China

In this paper, a high refractive index metamaterial （HRM）, whose element is composed of bilayer square patch （BSP） spaced by a dielectric plate, is proposed. By reducing the thickness of the dielectric plate and the gap between adjacent patches, the BSP can effectively enhance capacitive coupling and simultaneously suppress diamagnetic response, which significantly increases the refractive index of the proposed metamaterial. Furthermore, the high refractive index region is far away from the resonant region of the metamaterial, resulting in broadband. Based on these characteristics of BSP, a gradient refractive index （GRIN） lens with thin thickness （0.34/~0, where 2~0 is the wavelength at 5.75 GHz） is designed. By using this lens, we then design a circularly polarized horn antenna with high performance. The measurement results show that the 3-dB axial ratio bandwidth is 34.8% （4.75 GHz-6.75 GHz） and the antenna gain in this frequency range is increased by an average value of 3.4 dB. The proposed method opens up a new avenue to design high-performance antenna.

关键词： circularly polarized horn antenna high refractive index lens, metamaterial.

Synthesis and Crystal Structure of [(Praseodymium)_2(3,5-Binitro Benzoyloxy)_6 (Dimethyl Sulfoxide)_4] Complex

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Chinese Journal of Structural Chemistry 2001年第6期20卷 473-477页

作者： NIU De-Zhong MU lai-long LU Zai-Sheng WANG Yu-Cheng CHEN Jiu-Tong Department of Chemistry Xuzhou Normal UniversityJiangsu 221009China Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002China

A novel one-dimensional chain complex [Pr2(bnbo)6(DMSO)4] (bnbo=3,5-binitro benzoyloxy, DMSO= dimethyl sulfoxide) with bridging carboxyl groups was synthesized and its structure has been determined by single-crystal X-ray methods. In the complex, a pair of adjacent metal ions are alternately connected by four or two carboxylate groups to form an infinite chain of 8-coordinated Pr3+ ions. The complex (Pr2C50H42N12O40S4 ) crystal system is triclinic, with space group P1, a=14.2890(3), b=14.3427(3), c=20.1601(2)? =76.636(1), b=84.496(1), =60.316(1)? V=3491.4(1)?, Z=2, Mr =1861.02, Dc=1.770 g/cm3, m=1.608mm-1, F(000)=1856, the final R=0.0776 and wR=0.1724 for 8804 reflections with I > 2s(I).

关键词： crystal structure praseodymium 3 5-binitro benzoyloxy dimethyl sulfoxide complex

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组织工程技术修复颞下颌关节:问题与挑战

中国组织工程研究 2025年第22期29卷 4804-4812页

作者：赖鹏宇梁冉沈山暨南大学口腔医学院广东省广州市510632

背景:颞下颌关节疾病的传统疗法受限于疾病严重程度和个体差异。相比之下,组织工程作为一种新兴治疗方法,可以根据患者具体情况定制个性化治疗方案,减少手术过程中的不确定性,提高治疗效果。目的:综述组织工程修复颞下颌关节的最新研究... 详细信息

背景:颞下颌关节疾病的传统疗法受限于疾病严重程度和个体差异。相比之下,组织工程作为一种新兴治疗方法,可以根据患者具体情况定制个性化治疗方案,减少手术过程中的不确定性,提高治疗效果。目的:综述组织工程修复颞下颌关节的最新研究成果和进展。方法:以“颞下颌关节,组织工程,种子细胞,支架,生长因子,动物模型”为中文检索词,以“temporomandibular joint,tissue engineering,seed cell,scaffold,growth factor,animal model”为英文检索词,分别在PubMed数据库和中国知网进行文献检索,检索时限为各数据库建库时间至2024年3月。通过分析和阅读文献进行筛选,按照排除筛选标准纳入文献,最终纳入57篇文献进行综述。结果与结论:(1)随着生物学、材料学与工程学等技术的发展,颞下颌关节组织工程己取得较大进展,例如种子细胞的筛选、新型支架的开发、生长因子作用机制的探索、多种动物模型的构建等,目前大多数研究尚处于体外实验阶段,动物实验等体内研究尚未大规模开展,组织工程修复颞下颌关节的临床应用还需更多证据支持。(2)尽管颞下颌关节组织工程研究仍存在许多问题和挑战等待解决,依然展现出广阔的临床应用前景,有望在将来成为颞下颌关节疾病出色高效的治疗方式。

关键词：组织工程颞下颌关节软骨缺损种子细胞支架水凝胶脱细胞外基质生长因子外泌体动物模型

Studies on photodynamic mechanism of a novel chlorine derivative(TDPC)and its antitumor effect forphotodynamic therapy in vitro and in vivo

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Journal of Innovative Optical Health Sciences 2015年第1期8卷 60-67页

作者： Ying Ye lai-Xing Wang Dan-Ping Zhang Yi-Jia Yan Zhi-long Chen Department of Pharmaceutical Science&Technology College of Chemistry and Biology Donghua University Shanghai 201620P.R.China Changhai Hospital Second Military Medical University Shanghai 200433P.R.China

Photodynamic therapy(PDT)represents a promising method for treatment of cancerous *** chemical and physical properties of used photosensitizer(PS)play key roles in the treat ment *** this study,a novel PS,5,10,15,20-tetrais((5-dipropylamino)pentyl)-chlorin(TDPC)which displayed a characteristic long wavelength absorption peak at 650 nm were *** also shows a singlet oxygen generation rate of 4.257 min^(-1).Generally,TDPC is localized in mitochondria and nucleus of *** light irradiation with 650 nm laser,it can kill many types of cell,in addition,TDPC-PDT can destroy ECA-109 tunor in nude mice and a necrotic scab was formed *** expression levels of many genes which regulated cell growth and apoptosis were determined by RT-PCR following *** results showed that it either increased or decreased,among which,the expression level of TNFSF13,a member of tumor necrosis factor superfamily,increased *** general,TDPC is an elective antitumor PS in vitro and in vito and is worthy of further study as a new drug ***13 will be an important molecular target for the discovery of new PSs.

关键词： Photosensitizer photodynamic therapy tumor chlorin TDPC

Study of the crosstalk evaluation for cavity BPM

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Nuclear Science and Techniques 2018年第6期29卷 67-75页

作者： Jian Chen Yong-Bin Leng Lu-Yang Yu long-Wei lai Ren-Xian Yuan Shanghai Institute of Applied Physics Chinese Academy of Science Shanghai 201204 China University of the Chinese Academy of Science Beijing 100049 China

In order to pursue high-precision beam position measurements for free-electron laser facilities, a cavity beam position monitor(CBPM) is employed to measure the transverse position that can meet the requirement of position resolution at a sub-micrometer or even nanometer scale. However, for the pill-box cavity BPM, crosstalk between the cavities will have an effect on the accurate measurement of beam position. To reduce the effect of crosstalk on CBPM performance and ease the measurement of the isolation between the cavities, the cavities with a slight difference in resonant frequency were designed and applied in the Dalian coherent light source and Shanghai soft X-ray free-electron laser facilities. Furthermore, two methods, the principal component analysis method and the method of harmonic analysis, are proposed in this paper to evaluate the crosstalk. The results demonstrate that the two methods are feasible in evaluating the crosstalk between the cavities.

关键词： BPM 串音评估位置分辨率学习精确测量激光设备主要部件