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Discovering Cathodic Biocompatibility for Aqueous Zn–MnO_(2) Battery:An Integrating Biomass Carbon Strategy
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作者 Wei Lv Zilei Shen +10 位作者 Xudong Li Jingwen Meng Weijie Yang Fang Ding Xing Ju Feng Ye Yiming Li Xuefeng Lyu miaomiao wang Yonglan Tian Chao Xu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期111-126,共16页
Developing high-performance aqueous Zn-ion batteries from sustainable biomass becomes increasingly vital for large-scale energy storage in the foreseeable future.Therefore,γ-MnO_(2) uniformly loaded on N-doped carbon... Developing high-performance aqueous Zn-ion batteries from sustainable biomass becomes increasingly vital for large-scale energy storage in the foreseeable future.Therefore,γ-MnO_(2) uniformly loaded on N-doped carbon derived from grapefruit peel is successfully fabricated in this work,and particularly the composite cathode with carbon carrier quality percentage of 20 wt%delivers the specific capacity of 391.2 mAh g^(−1)at 0.1 A g^(−1),outstanding cyclic stability of 92.17%after 3000 cycles at 5 A g^(−1),and remarkable energy density of 553.12 Wh kg^(−1) together with superior coulombic efficiency of~100%.Additionally,the cathodic biosafety is further explored specifically through in vitro cell toxicity experiments,which verifies its tremendous potential in the application of clinical medicine.Besides,Zinc ion energy storage mechanism of the cathode is mainly discussed from the aspects of Jahn–Teller effect and Mn domains distribution combined with theoretical analysis and experimental data.Thus,a novel perspective of the conversion from biomass waste to biocompatible Mn-based cathode is successfully developed. 展开更多
关键词 Aqueous Zn-ion batteries BIOCOMPATIBILITY Jahn-Teller effect Mn domains γ-MnO_(2)
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Premature aging of skeletal stem/progenitor cells rather than osteoblasts causes bone loss with decreased mechanosensation
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作者 Ruici Yang Dandan Cao +6 位作者 Jinlong Suo Lingli Zhang Chunyang Mo miaomiao wang Ningning Niu Rui Yue Weiguo Zou 《Bone Research》 SCIE CAS CSCD 2023年第3期560-573,共14页
A distinct population of skeletal stem/progenitor cells(SSPCs)has been identified that is indispensable for the maintenance and remodeling of the adult skeleton.However,the cell types that are responsible for age-rela... A distinct population of skeletal stem/progenitor cells(SSPCs)has been identified that is indispensable for the maintenance and remodeling of the adult skeleton.However,the cell types that are responsible for age-related bone loss and the characteristic changes in these cells during aging remain to be determined.Here,we established models of premature aging by conditional depletion of Zmpste24(Z24)in mice and found that Prx1-dependent Z24 deletion,but not Osx-dependent Z24 deletion,caused significant bone loss.However,Acan-associated Z24 depletion caused only trabecular bone loss.Single-cell RNA sequencing(sc RNA-seq)revealed that two populations of SSPCs,one that differentiates into trabecular bone cells and another that differentiates into cortical bone cells,were significantly decreased in Prx1-Cre;Z24^(f/f)mice.Both premature SSPC populations exhibited apoptotic signaling pathway activation and decreased mechanosensation.Physical exercise reversed the effects of Z24depletion on cellular apoptosis,extracellular matrix expression and bone mass.This study identified two populations of SSPCs that are responsible for premature aging-related bone loss.The impairment of mechanosensation in Z24-deficient SSPCs provides new insight into how physical exercise can be used to prevent bone aging. 展开更多
关键词 SENSATION PROGENITOR mec
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A case of pulmonary mucormycosis presented with cardiac arrest
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作者 Haijiang Zhou Xuan Qi +11 位作者 Jifei Cai Wenxin Liu Chenyu Kang Guyu Zhang miaomiao wang Xuefei Xie Chao Liang Lihua Liu Jie Gao Wei Yuan Xue Mei Shubin Guo 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第6期484-487,共4页
Mucormycosis is an uncommon and opportunistic fungal infection with high mortality. Infections may result from ingestion of contaminated food, inhalation of spores into the respiratory tract or inoculation into disrup... Mucormycosis is an uncommon and opportunistic fungal infection with high mortality. Infections may result from ingestion of contaminated food, inhalation of spores into the respiratory tract or inoculation into disruptedskin.^([1])Pulmonarymucormycosis(PM)is the most common clinical type. 展开更多
关键词 COR MORTALITY RESPIRATORY
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An Industrial Perspective on Magnesium Alloy Wheels: A Process and Material Design
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作者 miaomiao wang 《Materials Sciences and Applications》 CAS 2023年第1期20-44,共25页
Light weights wheels improve vehicle performance with respect to road handling, cornering as well providing fuel economy and reduced greenhouse gas emissions. Aluminum wheels are currently used in many models and are ... Light weights wheels improve vehicle performance with respect to road handling, cornering as well providing fuel economy and reduced greenhouse gas emissions. Aluminum wheels are currently used in many models and are produced usually by low pressure assisted gravity casting. Important property requirements are fatigue strength, pressure tightness, tensile strength, impact resistance, and corrosion resistance. Many attempts have been made to convert aluminum road wheels to magnesium. Race cars and some of the high end models (Porsche, Ferrari, etc.) have used magnesium wheels. These wheels have been gravity cast or forged. Viable corrosion protection systems have been developed and magnesium wheels have been used with success on these models. To use magnesium on more modest models is a challenge due to cost issues. Higher productivity casting processes or more cost effective coating systems need to be utilized. The project consists of selecting magnesium alloys for road wheels, examining the possible cost effective casting processes and corrosion protection systems, evaluating the cost per one wheel and comparing it to aluminum wheel costs. The wheels will also be compared with respect to fatigue and impact properties, pressure tightness, and corrosion. 展开更多
关键词 Manufacturing Process DIE-CASTING Corrosion Resistance Economic Viability
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遗传性牙龈纤维瘤病一家族三代1例 被引量:2
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作者 贺秀芳 许春姣 +3 位作者 田地 王苗苗 张文瑞 郭怡婷 《华西口腔医学杂志》 CAS CSCD 北大核心 2020年第1期104-107,共4页
遗传性牙龈纤维瘤病是一种罕见的家族遗传性疾病,以牙龈组织缓慢、渐进性增生为主要特征。本文对1例遗传性牙龈纤维瘤病家族进行报道及文献回顾。
关键词 遗传性牙龈纤维瘤病 基因 牙龈增生
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Genome Wide Transcriptomic Analysis of <i>WRKY</i>Gene Family Response to Biotic Stresses in <i>Malus</i>×<i>domestica</i>
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作者 Hanghang Zhang Liu Yang +10 位作者 Ruli Zhou Yingli Zhang Zhengyang wang Hongguang Pang Tuanhui Bai Shangwei Song Jian Jiao miaomiao wang Jiancan Feng Chunhui Song Xianbo Zheng 《American Journal of Plant Sciences》 2021年第5期858-885,共28页
Apple (<i><span style="font-family:Verdana;">Malus </span></i><span style="font-family:Verdana;">× </span><i><span style="font-family:Verdana;... Apple (<i><span style="font-family:Verdana;">Malus </span></i><span style="font-family:Verdana;">× </span><i><span style="font-family:Verdana;">domestica </span></i><span style="font-family:Verdana;">Borkh.)</span><b><i> </i></b><span style="font-family:Verdana;">is a perennial woody plant that often suffers from various biological stresses. Many harmful pathogens can infect apple trees and lead to reduced production. We comprehensively identified the </span><i><span style="font-family:Verdana;">WRKY</span></i><span style="font-family:Verdana;"> genes in the apple genome and analyzed their expression in response to several biological stressors, including </span><i><span style="font-family:Verdana;">Alternaria alternata</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Pythium ultimum</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Botryosphaeria dothidea</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Erwinia amylovora</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Penicillium expansum</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Gymnosporangium yamadae</span></i><span style="font-family:Verdana;">, and Apple replant disease. There were 113 </span><i><span style="font-family:Verdana;">MdWRKYs</span></i><span style="font-family:Verdana;"> identified in the apple genome. Twenty-two </span><i><span style="font-family:Verdana;">MdWRKYs</span></i><span style="font-family:Verdana;"> were differentially expressed in response to at least five pathogens. Promoter sequence analysis showed that these genes carried many defense- and stress-responsive elements, such as MeJA-response elements, salicylic acid-response elements, and W-box elements, in their promoters. Transient expression assays showed that </span><i><span style="font-family:Verdana;">MdWRKY</span></i><span style="font-family:Verdana;">40</span><i><span style="font-family:Verdana;">a</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">MdWRKY</span></i><span style="font-family:Verdana;">54</span><i><span style="font-family:Verdana;">h</span></i><span style="font-family:Verdana;"> played negative roles in defense against </span><i><span style="font-family:Verdana;">B. dothidea</span></i><span style="font-family:Verdana;"> infection. </span><i><span style="font-family:Verdana;">WRKY</span></i><span style="font-family:Verdana;">40 and </span><i><span style="font-family:Verdana;">WRKY</span></i><span style="font-family:Verdana;">60 and the </span><i><span style="font-family:Verdana;">MdWKRY</span></i><span style="font-family:Verdana;">33</span><i><span style="font-family:Verdana;">s</span></i><span style="font-family:Verdana;"> might play important roles in responding to pathogens and are conserved in some plants. These differentially expressed </span><i><span style="font-family:Verdana;">MdWRKYs</span></i><span style="font-family:Verdana;"> might play key roles in the apple response to multiple pathogens.</span> 展开更多
关键词 Apple WRKY Transcription Factor PATHOGENS Big Data
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Study on the method of precision adjustment of star sensor 被引量:1
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作者 Xiaoyan wang Ran Zheng +4 位作者 Yanpeng Wu Jianbo Sun Jun Zhong Long wang miaomiao wang 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2018年第4期248-257,共10页
Star sensors are indispensable spatial measurement sensors for high-resolution earth observation and astronomical observations, and the demand for high measurement accuracy of satellite sensors continues to increase; ... Star sensors are indispensable spatial measurement sensors for high-resolution earth observation and astronomical observations, and the demand for high measurement accuracy of satellite sensors continues to increase; thus, the star sensor optical machine adjustment error cannot be ignored. The commonly used installation error correction method cannot solely meet the precision analysis requirements. In this paper, the relationship between the optical machine installation and the star sensor measurement error is analyzed, and several common adjustment error correction methods are compared. An adjustment method for optical machines is proposed to meet the requirements of very high precision star sensors. The assembly precision requirements of the investigated very high precision star sensor are analyzed considering the whole machine, and then the optical components are controlled through optical precision adjustments to satisfy the precision requirements. Finally, through the complete machine calibration, the star sensor precision adjustment for an optical machine structure is verified. This method meets the requirements of very high precision sensors and is suitable for the precision adjustment of optical machine structures, which is of practical significance to improve the precision of star sensors. 展开更多
关键词 Very HIGH PRECISION STAR SENSOR Optical MACHINE structure ALIGNMENT PRECISION PRECISION adjustment
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Theoretical insights into interfacial and electronic structures of NiOx/SrTiO3 photocatalyst for overall water splitting
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作者 miaomiao wang Shenmin Li +1 位作者 Yang Lv Xin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第6期138-148,共11页
SrTiO3 is a promising candidate photocatalyst for overall water splitting.Loading suitable cocatalysts,such as NiOx,the mixture of Ni and NiO,remarkably improve the photocatalytic activity.However,spatial locations an... SrTiO3 is a promising candidate photocatalyst for overall water splitting.Loading suitable cocatalysts,such as NiOx,the mixture of Ni and NiO,remarkably improve the photocatalytic activity.However,spatial locations and functions of components in NiOx/SrTiO3 are under debate.Here,using first-principles density functional theory(DFT)calculations,we investigate the initial growth of Nin(n=1–4)and(NiO)n(n=1,2 and 4)clusters on stoichiometric(100)surfaces of SrTiO3,and explore interfacial and electronic structures of composite photocatalysts.It is found that Nin clusters are easier to undergo aggregation on SrO-termination than on TiO2-termination.The adsorption of Nincluster on(100)surfaces elevates the Fermi level towards the conduction band,which may benefit the occurrence of hydrogen evolution reaction.The structural similarity between(NiO)n cluster and surface has an essential effect on the most stable adsorption configuration.For(NiO)n/SrTiO3 systems,the occupied states of(NiO)n cluster well overlap with those of(100)surfaces in the valence band maximum,which is in favor of the separation of photogenerated electrons and holes to SrTiO3 support and(NiO)n cluster,respectively.The detailed DFT analysis provides important insights into the growth of NiOx on surfaces of SrTiO3and presents an explanation on the different models of NiOx/SrTiO3 photocatalyst proposed by experimental groups.Our calculations build a basis for further investigations on the mechanism of photocatalytic water-splitting reaction in NiOx/SrTiO3composite system. 展开更多
关键词 Semiconductor-based PHOTOCATALYST Density functional theory COCATALYST Electronic structure calculation SRTIO3
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First-principles investigation of β-Ge3N4 loaded with RuO2 cocatalyst for photocatalytic overall water splitting
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作者 Yanxia Ma miaomiao wang Xin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期24-32,共9页
β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic syst... β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst. 展开更多
关键词 β-Ge3N4 RUO2 COCATALYST PHOTOCATALYTIC water splitting Density functional theory
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响应面实验优化小麦胚芽淀粉酶解工艺 被引量:1
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作者 叶云芳 刘咏 +1 位作者 汪苗苗 王军辉 《食品与营养科学》 2018年第4期265-273,共9页
在加酶量、料液比、酶解时间及酶解温度四个单因素试验的基础上,运用响应面分析法,以小麦胚芽中还原糖含量为评价指标,对α-淀粉酶酶解小麦胚芽中淀粉的最佳工艺进行了研究,并利用统计学方法建立了α-淀粉酶酶解小麦胚芽淀粉的二次多项... 在加酶量、料液比、酶解时间及酶解温度四个单因素试验的基础上,运用响应面分析法,以小麦胚芽中还原糖含量为评价指标,对α-淀粉酶酶解小麦胚芽中淀粉的最佳工艺进行了研究,并利用统计学方法建立了α-淀粉酶酶解小麦胚芽淀粉的二次多项数学模型。结果表明,最佳酶解条件为:酶添加量44 U/mL,酶解温度88℃,酶解时间70 min。在此条件下酶解产物的还原糖含量达(14.75 &#177;0.36)%。该试验用响应面法优选出的酶解工艺合理可行,为小麦胚芽固体饮料的开发提供了理论依据。 展开更多
关键词 小麦胚芽 酶解 响应面法 工艺优化
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Exploring the mechanism of Ta_(3)N_(5)/KTaO_(3) photocatalyst for overall water splitting by first-principles calculations
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作者 Yanxia Ma Yumeng Fo +3 位作者 miaomiao wang Xixi Liang Hao Dong Xin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期353-364,共12页
The rational fabrication of heterostructures is one of efficient strategies for improving photocatalytic performance of semiconductor photocatalysts.Very recently,Domen and co-workers found that Ta_(3)N_(5) single cry... The rational fabrication of heterostructures is one of efficient strategies for improving photocatalytic performance of semiconductor photocatalysts.Very recently,Domen and co-workers found that Ta_(3)N_(5) single crystals grown on the surface of KTaO_(3) can accomplish photocatalytic overall water splitting for the first time.In order to comprehend the underlying mechanism of this photocatalytic system,we have performed a systematic study based on density functional theory first-principles calculations.Ta_(3)N_(5)(010)/KTaO_(3)(110)slab models have been built according to experimental observations by considering two common terminations of KTaO_(3)(110)surface,named as Ta_(3)N_(5)/O_(2) and Ta_(3)N_(5)/KTaO.The formations of interfacial bonds are thermodynamically stable,showing a covalent interaction between two components of a heterostructure.Ta_(3)N_(5)/O_(2) has a higher mobility of photogenerated charge carriers and lower recombination rate of charge carriers than Ta_(3)N_(5)/KTaO.The light absorption of heterostructures displays the feature of KTaO_(3) in the short wavelength region and the characteristic of Ta_(3)N_(5) in the long wavelength region.The calculated band offsets show that Ta_(3)N_(5)/O_(2) and Ta_(3)N_(5)/KTaO have distinct Type-II band alignments,with Ta_(3)N_(5) as the accumulator of photoinduced electrons in the former and the collector of photogenerated holes in the latter,respectively.The difference in charge density and electrostatic potential between two components acts as a driving force to promote the transfer of electrons and holes to different domains of the interface,which is beneficial to extend the lifetime of photoinduced carriers.Our results demonstrate that the function of Ta_(3)N_(5) in Ta_(3)N_(5)/KTaO_(3) photocatalytic system is determined by the termination property of KTaO_(3)(110)surface,which provides a likely reason of the observed photocatalytic activity of overall water splitting achieved by Ta_(3)N_(5) synthesized by using KTaO_(3) as a precursor for the nitridation reaction. 展开更多
关键词 Ta3N5 Density functional theory calculations Separation of photogenerated carriers Semiconductor-based photocatalyst Overall water splitting
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Exogenous melatonin alleviated growth inhibition and oxidative stress induced by drought stress in apple rootstock
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作者 MEIGE wang JUAN GONG +6 位作者 CHUNHUI SONG ZHENGYANG wang SHANGWEI SONG JIAN JIAO miaomiao wang XIANBO ZHANG TUANHUI BAI 《BIOCELL》 SCIE 2022年第7期1763-1770,共8页
Drought stress is one of the major environmental obstacles that limit the production and development of apples(Malus domestica Borkh.).The role of melatonin is well known in the protection of plants under environmenta... Drought stress is one of the major environmental obstacles that limit the production and development of apples(Malus domestica Borkh.).The role of melatonin is well known in the protection of plants under environmental stresses.In this study,we investigated the effect of melatonin on apple rootstock M.hupehensis Rehd under drought stress.The results showed that drought inhibited the growth of M.hupehensis and dramatically reduced root surface area,root volume,the number of tips and forks,and root diameter.Drought-induced growth inhibition was significantly decreased by adding melatonin.Net photosynthetic rate(Pn),intercellular CO_(2)concentration(Ci),stomatal conductance(Gs),transpiration rate(Tr),were markedly reduced under drought stress.However,the application of melatonin could mitigate the damage to the photosynthetic apparatus and increase the quantum yield of PSII photochemistry.Additionally,generation of hydrogen peroxide(H_(2)O_(2))and superoxide radicals(O_(2)^(•–))sharply increased in apple leaves after 4 days under drought stress,and the accumulation of electrolyte leakage(EL)represented oxidative stress,while by applying melatonin under drought stress,the generation of O_(2)^(•–)and H_(2)O_(2)were significantly reduced and protected the membrane from drought damages.These results suggest that the adverse effects of drought can be minimized by applying melatonin to apples. 展开更多
关键词 Apple Chlorophyll fluorescence DROUGHT MELATONIN PHOTOSYNTHESIS
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Vertebrae CT Images 3D Reconstruction with Improve Marching Cubes Algorithm
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作者 Xia Liu Huan Liu +1 位作者 miaomiao wang Bo wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第6期69-79,共11页
Medical images 3D reconstruction is an important part in medical image analysis and processing. Although lots of algorithms have been proposed continuously, speed and accuracy cannot conform to actual needs, which has... Medical images 3D reconstruction is an important part in medical image analysis and processing. Although lots of algorithms have been proposed continuously, speed and accuracy cannot conform to actual needs, which has always been the focus topic. In this paper, we propose an Improved Marching Cubes algorithm ( I-MC) based on the surface rendering theory, which implements 3D reconstruction of the vertebrae. Firstly, we preprocessed the original 2D vertebrae CT images with the bilateral-filter denoising algorithm. Secondly, on the basis of the traditional Marching Cubes algorithm, the seed voxels were extracted and the Region Growing algorithm was used to determine all voxels that contain isosurfaces. Then, the Golden Section instead of the traditional linear interpolation was used to calculate the equivalent point, and this method reduced the calculations of public edges. VTK and OpenGL implemented 3D reconstruction of the vertebrae on GPU quickly and accurately. The experimental results show that when compared with the traditional Marching Cubes algorithm and Mesh Simplification Marching Cubes algorithm, the improved algorithm achieves a significant improvement of reconstruction speed while preserving the accurate results. The efficiency of algorithm is improved dramatically. This method is real-time and achieves the goal of efficient 3D reconstruction of vertebrae CT images. 展开更多
关键词 vertebrae CT Marching Cubes 3D reconstruction
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海岛型城市红火蚁发生程度空间格局及驱动因子——以福建海坛岛为例
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作者 陈宏 冼晓青 +4 位作者 陈宜雪 林娜 王苗苗 李志鹏 赵健 《生物多样性》 CAS CSCD 北大核心 2023年第5期110-121,共12页
红火蚁(Solenopsis invicta)是极具危险性的外来入侵物种,研究海岛在城市化发展中红火蚁发生程度的空间格局及驱动因子,对保护海岛生态安全具有重要意义。本研究以福建省东部的海坛岛为例,运用核密度、空间自相关模型分析红火蚁发生程... 红火蚁(Solenopsis invicta)是极具危险性的外来入侵物种,研究海岛在城市化发展中红火蚁发生程度的空间格局及驱动因子,对保护海岛生态安全具有重要意义。本研究以福建省东部的海坛岛为例,运用核密度、空间自相关模型分析红火蚁发生程度空间格局,进一步运用地理探测器揭示环境因子(8种)、社会经济因子(10种)以及两类因子交互作用对红火蚁发生程度的影响。结果显示:研究区红火蚁发生程度空间密度表现为不均匀聚集特征,农田发生程度最为严重(高-高聚集)、园林绿化用地次之(高-低聚集和低-低聚集)、居民区周边最轻,且发生区域呈现正向空间自相关关系。18种影响因子对红火蚁发生程度空间分异解释度的q值范围为0.014–0.278。从整体上看,两类因子对红火蚁发生程度的影响存在差异,且社会经济因子q值平均数高于环境因子。对红火蚁发生程度影响最大的经济因子是农村人口数量(q=0.278),其次为乡镇面积(q=0.268)。在环境因子中,土壤类型(q=0.172)和年均降水量(q=0.149)的影响力较强。环境因子与社会经济因子两两叠加作用都将正向增强红火蚁的发生程度,其中,乡镇面积与邻近景区距离、年均降水量与邻近景区距离两组因子交互作用对红火蚁发生程度的影响力最大(q=0.466)。本研究结果表明农业耕作、城镇化建设中绿化苗木引种、道路交通运输对海岛型城市红火蚁发生程度的空间格局起到关键性作用。因此,在防控中不仅要加强对调运苗木和往来货物的检疫,还应采取因地适宜的防控措施,有效抑制红火蚁种群数量和扩散速度。 展开更多
关键词 红火蚁 海岛型城市 空间格局 地理探测器 海坛岛
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Image motion and experimental study of a 0.1″space pointing measuring instrument for micro-vibration conditions 被引量:2
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作者 Lin LI Li YUAN +5 位作者 Li wang miaomiao wang Xiaoxue GONG Jie SUI Yanpeng WU Ran ZHENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期191-200,共10页
There exists an increasing need for Milli-Arc-Seconds(MAS)accuracy pointing measurement for current and future space systems.To meet the 0.1″space pointing measurement accuracy requirements of spacecraft in future,th... There exists an increasing need for Milli-Arc-Seconds(MAS)accuracy pointing measurement for current and future space systems.To meet the 0.1″space pointing measurement accuracy requirements of spacecraft in future,the influence of spacecraft micro-vibration on a 0.1″Space Pointing Measuring Instrument(SPMI)is studied.A Quasi-Zero Stiffness Device(QZSD)with adaptive adjustment and variable stroke was proposed.Then,a series of micro-vibration experiments of the SPMI were carried out.The influence of the micro-vibration generated by Guidance Navigation Control(GNC)attitude control components under different attitudes on the SPMI was analyzed.Point spread function of image motion in micro-vibration was also derived.Further,the changes of image motion under the micro-vibration environment were evaluated by extracting the gray centroid of the images,and the experiment processes and results are deeply discussed.The results show that the firstorder frequency of the QZSD system is 0.114 Hz,and it is induced by a double pendulum system;the image motion of single flywheel spinning reached 0.015 pixels;whilst the image motion reached 0.03 pixels when three flywheels are combined spinning.These latest findings provide a beneficial theoretical and technical support for the development of spacecraft with 0·1″pointing accuracy. 展开更多
关键词 Image motion MICRO-VIBRATION Milli-arc-seconds Quasi-zero stiffness device Space pointing measuring instrument
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An improved method that incorporates the estimated runoff for peak discharge prediction on the Chinese Loess Plateau 被引量:1
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作者 Wenhai Shi miaomiao wang +2 位作者 Donghao Li Xianwei Li Mengying Sun 《International Soil and Water Conservation Research》 SCIE CSCD 2023年第2期290-300,共11页
An accurate prediction of peak discharge in watersheds is critical not only for water resource manage-ment,but also for understanding the complex relationships of hydrological processes.In this study,a modified peak d... An accurate prediction of peak discharge in watersheds is critical not only for water resource manage-ment,but also for understanding the complex relationships of hydrological processes.In this study,a modified peak discharge formula based on the Chemicals,Runoff,and Erosion from Agricultural Man-agement Systems(CREAMS)model was developed by introducing rainfall intensity and soil moisture factors.The reliability of the proposed method was tested with data from 1464 storm events in 41 watersheds and was applied to 256 storm events in five remaining typical watersheds using the opti-mized parameters.The results indicate that the proposed method is highly accurate in terms of model efficiency,as determined by Nash-Sutcliffe efficiencies(NSEs)of 88.60%,74.04%,and 90.12%during the calibration,validation,and application cases,respectively.Furthermore,it performed better than the original and modified CREAMS methods.Subsequently,using the parameters derived from the initial 41 watersheds and the runoff estimated using the modified Soil Conservation Service curve number(SCS-CN)method,the proposed method was used to predict the peak discharge from the last five typical watersheds.Large NSE(63.88-80.83%)and low root mean square error(RMSE)values(0.31-35.93 m^(3)s^(-1))were obtained for the five watersheds.Overall,the proposed peak discharge model,combined with the modified SCS-CN method,may accurately predict event-based peak discharge and runoff for general applications under various hydrological and geomorphic conditions in the Loess Plateau region. 展开更多
关键词 Chemicals Runoff and Erosion from agricultural management systems (CREAMS) NRCS-CN Peak discharge Surface runoff Rainfall intensity
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An Autoregressive Integrated Moving Average Model for Predicting Varicella Outbreaks — China, 2019 被引量:1
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作者 miaomiao wang Zhuojun Jiang +5 位作者 Meiying You Tianqi wang Li Ma Xudong Li Yuehua Hu Dapeng Yin 《China CDC weekly》 SCIE CSCD 2023年第31期698-702,I0002,I0003,共7页
Introduction:Varicella,a prevalent respiratory infection among children,has become an escalating public health issue in China.The potential to considerably mitigate and control these outbreaks lies in surveillance-bas... Introduction:Varicella,a prevalent respiratory infection among children,has become an escalating public health issue in China.The potential to considerably mitigate and control these outbreaks lies in surveillance-based early warning systems.This research employed an autoregressive integrated moving average(ARIMA)model with the objective of predicting future varicella outbreaks in the country.Methods:An ARIMA model was developed and fine-tuned using historical data on the monthly instances of varicella outbreaks reported in China from 2005 to 2018.To determine statistically significant models,parameter and Ljung-Box tests were employed.The coefficients of determination(R2)and the normalized Bayesian Information Criterion(BIC)were compared to selecting an optimal model.This chosen model was subsequently utilized to forecast varicella outbreak cases for the year 2019.Results:Four models passed parameter(all P<0.05)and Ljung-Box tests(all P>0.05).ARIMA(1,1,1)×(0,1,1)12 was determined to be the optimal model based on its coefficient of determination R2(0.271)and standardized BIC(14.970).Fitted values made by the ARIMA(1,1,1)×(0,1,1)12 model closely followed the values observed in 2019,the average relative error between the actual value and the predicted value is 15.2%.Conclusion:The ARIMA model can be employed to predict impending trends in varicella outbreaks.This serves to offer a scientific benchmark for strategies concerning varicella prevention and control. 展开更多
关键词 ARIMA PREVENTION utilized
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Epidemiological Characteristics of Varicella Outbreaks—China,2006–2022 被引量:1
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作者 miaomiao wang Xudong Li +7 位作者 Meiying You Yuanyuan wang Xinyu Liu Zihan Li Wenjia Zhao Zhuojun Jiang Yuehua Hu Dapeng Yin 《China CDC weekly》 SCIE CSCD 2023年第52期1161-1166,共6页
Introduction:Varicella outbreaks significantly disrupt schools and other child-centered institutions.This study aimed to identify patterns and epidemiological features of varicella outbreaks in China from 2006 to 2022... Introduction:Varicella outbreaks significantly disrupt schools and other child-centered institutions.This study aimed to identify patterns and epidemiological features of varicella outbreaks in China from 2006 to 2022.Methods:Data were extracted from outbreak reports submitted to the Public Health Emergency Reporting Management Information System within the specified timeframe.Analytical methods included Spearman correlation tests and the Mann-Kendall trend tests,conducted using R software to analyze and summarize reported data.Additionally,statistical analyses of trends and epidemiological characteristics were performed using SPSS software.Results:Between 2006 and 2022,a total of 11,990 varicella outbreaks were reported in China,resulting in 354,082 cases.The attack rates showed a decreasing trend over the years(Z=−4.49,P<0.05).These outbreaks occurred in two peaks annually.The eastern region accounted for the highest number of outbreaks(31.53%),followed by the southwestern(24.22%)and southern(17.93%)regions.Varicella outbreaks were most common in elementary schools.Most of the outbreaks(60.43%)were classified as Grade IV(general)severity,with 86.41%of the outbreaks having 10–49 cases.The median and inter-quartile ranges(IQR)of the duration of outbreaks,response time,and case counts were 21(10,39)days,4(0,12)days,and 23(16,35)cases,respectively.These variables showed a positive correlation(P<0.001).Conclusions:Varicella outbreaks exhibited fluctuating trends,initially decreasing until 2012,followed by an increase,reaching the highest peak in 2018–2019.Continual monitoring of varicella epidemiology is necessary to assess the burden of the disease and formulate evidence-based strategies and policies for its prevention and control. 展开更多
关键词 PREVENTION EPIDEMIOLOGY annually
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Upconversion luminescence and optical thermometry behaviors of Yb^(3+)and Ho^(3+)co‑doped GYTO crystal
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作者 Chuancheng Zhang Shoujun Ding +5 位作者 miaomiao wang Hao Ren Xubing Tang Yong Zou Renqin Dou Wenpeng Liu 《Frontiers of Optoelectronics》 EI CSCD 2023年第3期179-189,共11页
Optical thermometry based on the upconversion(UC)luminescence intensity ratio(LIR)has attracted considerable attention because of its feasibility for achievement of accurate non-contact temperature measurement.Compare... Optical thermometry based on the upconversion(UC)luminescence intensity ratio(LIR)has attracted considerable attention because of its feasibility for achievement of accurate non-contact temperature measurement.Compared with traditional UC phosphors,optical thermometry based on UC single crystals can achieve faster response and higher sensitivity due to the stability and high thermal conductivity of the single crystals.In this study,a high-quality 5 at%Yb^(3+)and 1 at%Ho^(3+)co-doped Gd_(0.74)Y_(0.2)TaO_(4)single crystal was grown by the Czochralski(Cz)method,and the structure of the as-grown crystal was characterized.Importantly,the UC luminescent properties and optical thermometry behaviors of this crystal were revealed.Under 980 nm wavelength excitation,green and red UC luminescence lines at 550 and 650 nm and corresponding to the^(5)F_(4)/^(5)S_(2)→^(5)I_(8)and^(5)F_(5)→^(5)I_(8)transitions of Ho^(3+),respectively,were observed.The green and red UC emissions involved a two-photon mechanism,as evidenced by the analysis of power-dependent UC emission spectra.The temperature-dependent UC emission spectra were measured in the temperature range of 330–660 K to assess the optical temperature sensing behavior.At 660 K,the maximum relative sensing sensitivity(S_(r))was determined to be 0.0037 K^(−1).These results highlight the signifcant potential of Yb,Ho:GYTO single crystal for optical temperature sensors. 展开更多
关键词 Yb Ho:GYTO Optical temperature sensor Luminescence intensity ratio Upconversion luminescence
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Symmetric Mach reflection configuration with asymmetric unsteady solution
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作者 Chenyuan BAI miaomiao wang Ziniu WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第4期75-78,共4页
Symmetric Mach reflection in steady supersonic flow has been usually studied by solving a half-plane problem with the symmetric line treated as reflecting surface,thus losing the opportunity to discover antisymmetric ... Symmetric Mach reflection in steady supersonic flow has been usually studied by solving a half-plane problem with the symmetric line treated as reflecting surface,thus losing the opportunity to discover antisymmetric flow structures.Here in this paper we treat this problem as an entire-plane problem.Using an unsteady numerical approach,we find that the two sliplines exhibit antisymmetric unsteadiness if the Mach stem height is small while the flow remains symmetric if the Mach stem height is large.The mechanism by which disturbance,generated in the downstream of the flow duct between the two sliplines,propagates upstream is identified and it is also shown that the interaction between the transmitted expansion waves and the sliplines increases the amplitude of the unstable modes.The present study suggests a new type of compressible jet that deserves further studies. 展开更多
关键词 Antisymmetric solution Mach reflection Shock reflection Supersonic flow
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