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Topographies of Organized Monolayer of α-Amylase Observed by Atomic Force Microscopy 被引量:1
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作者 Lin HE Xian Fu LIN +1 位作者 De Shui LV Zhi Chun CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第1期87-90,共4页
In this paper, (-amylase organized monolayer was assembled on the surface of the PET-CO2- substrate in different conditions. The different topography of the (-amylase/PET monolayer was obtained by AFM in tapping mode.
关键词 Topography of monolayer (-amylase AFM self-assembly.
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GNSS Technology’s Contribution to Topography: Evaluative Study of Gaps between Methods Topographies
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作者 Cheikh Ahmed Tidiane Ly Joseph Mbagnick Louis Diene +1 位作者 Diogoye Diouf Alassane Ba 《Journal of Geographic Information System》 2021年第3期340-352,共13页
New information and communication technologies have led to the emergence of new techniques in our daily lives. Indeed, in topography, a lightning development of new techniques and new devices has been noticed. This de... New information and communication technologies have led to the emergence of new techniques in our daily lives. Indeed, in topography, a lightning development of new techniques and new devices has been noticed. This development has given rise to a multitude of choices of devices and various classes of precision. This implies that the decision-makers have to study the adequate equipment and the appropriate technique according to the topographic task to be realized. The objective is not to compare GNSS and topographic techniques, but to point out the contribution of the Global Navigation Satelite System (GNSS) techniques of topographic work. Thus, a theoretical study with a critical eye on the scientific principle of calculating the third topographic dimension followed by a leveling campaign, Real Time Kinematic (RTK) surveys will be used in order to be able to compare and interpret the result from these campaigns. The study of the difference resulting from the practical campaigns will allow us to identify the contribution of GNSS technology. 展开更多
关键词 TOPOGRAPHY GNSS Technic ACCURACY CONTRIBUTION
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Replication of natural surface topographies to generate advanced cell culture substrates
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作者 N.O.Monteiro J.F.Fangueiro +1 位作者 R.L.Reis N.M.Neves 《Bioactive Materials》 SCIE CSCD 2023年第10期337-347,共11页
Surface topographies of cell culture substrates can be used to generate in vitro cell culture environments similar to the in vivo cell niches. In vivo, the physical properties of the extracellular matrix (ECM), such a... Surface topographies of cell culture substrates can be used to generate in vitro cell culture environments similar to the in vivo cell niches. In vivo, the physical properties of the extracellular matrix (ECM), such as its topography, provide physical cues that play an important role in modulating cell function. Mimicking these properties remains a challenge to provide in vitro realistic environments for cells. Artificially generated substrates’ topographies were used extensively to explore this important surface cue. More recently, the replication of natural surface topographies has been enabling to exploration of characteristics such as hierarchy and size scales relevant for cells as advanced biomimetic substrates. These substrates offer more realistic and mimetic environments regarding the topographies found in vivo. This review will highlight the use of natural surface topographies as a template to generate substrates for in-vitro cell culture. This review starts with an analysis of the main cell functions that can be regulated by the substrate’s surface topography through cell-substrate interactions. Then, we will discuss research works wherein substrates for cell biology decorated with natural surface topographies were used and investigated regarding their influence on cellular performance. At the end of this review, we will highlight the advantages and challenges of the use of natural surface topographies as a template for the generation of advanced substrates for cell culture. 展开更多
关键词 Biomimetic topography Cell culture substrates Natural surface topographies
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Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa
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作者 Mei Chen Sheng-He Wu +6 位作者 Rui-Feng Wang Jia-Jia Zhang Peng-Fei Xie Min Wang Xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期125-142,共18页
Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,w... Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.e.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.e.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.e.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems. 展开更多
关键词 Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean
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Three-dimensional crystal defect imaging by STEM depth sectioning
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作者 Ryo Ishikawa Naoya Shibata and Yuichi Ikuhara 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期2-7,共6页
One of the major innovations awaiting in electron microscopy is full three-dimensional imaging at atomic resolution.Despite the success of aberration correction to deep sub-angstrom lateral resolution,spatial resoluti... One of the major innovations awaiting in electron microscopy is full three-dimensional imaging at atomic resolution.Despite the success of aberration correction to deep sub-angstrom lateral resolution,spatial resolution in depth is still far from atomic resolution.In scanning transmission electron microscopy(STEM),this poor depth resolution is due to the limitation of the illumination angle.To overcome this physical limitation,it is essential to implement a next-generation aberration corrector in STEM that can significantly improve the depth resolution.This review discusses the capability of depth sectioning for three-dimensional imaging combined with large-angle illumination STEM.Furthermore,the statistical analysis approach remarkably improves the depth resolution,making it possible to achieve three-dimensional atomic resolution imaging at oxide surfaces.We will also discuss the future prospects of three-dimensional imaging at atomic resolution by STEM depth sectioning. 展开更多
关键词 atomic-resolution STEM STEM depth sectioning depth resolution DOPANTS surface topography
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Substrate topography as a powerful tool to modify glial cell biology and interactions
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作者 Pascal Achenbach Haktan Altinova Gary A.Brook 《Neural Regeneration Research》 SCIE CAS 2025年第5期1390-1391,共2页
Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.... Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.Under normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses. 展开更多
关键词 INJURIES TOPOGRAPHY system
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High-precision X-ray characterization for basic materials in modern high-end integrated circuit
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作者 Weiran Zhao Qiuqi Mo +3 位作者 Li Zheng Zhongliang Li Xiaowei Zhang Yuehui Yu 《Journal of Semiconductors》 EI CAS CSCD 2024年第7期12-24,共13页
Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has... Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has undergone an extraordinary evolution.As the reliability requirements of integrated circuits continue to increase,the industry is placing greater emphasis on the crystal qualities.Consequently,conducting a range of characterization tests on the crystals has become necessary.This paper will examine the correlation between crystal quality,device performance,and production yield,emphasizing the significance of crystal characterization tests and the important role of high-precision synchrotron radiation X-ray topography characterization in semiconductor analysis.Finally,we will cover the specific applications of synchrotron radiation characterization in the development of semiconductor materials. 展开更多
关键词 X-ray topography synchrotron radiation semiconductor materials crystal defects
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One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer
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作者 Wen-Ting Tang Xiang-Ning Luo +4 位作者 Wen-Jing Zhao Jia Liao Xin-Yue Xu Hui-Dan Zhang Li Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期324-330,共7页
AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ... AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in children.METHODS:This randomized clinical study was performed between Dec.2020 and Dec.2021.Participants were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual quality.The contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration analyzer.The one-way ANOVA was performed to assess the differences between the three groups.The correlation between the change in AL and RPR was calculated by Pearson’s correlation coefficient.RESULTS:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were presented.There were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM group.RPR 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCLUSION:Ortho-k with 5 mm BOZD can control myopia progression more effectively.The mechanism may be associated with greater myopic shifts in RPR. 展开更多
关键词 relative peripheral refraction ORTHOKERATOLOGY MYOPIA back optic zone diameter axial length multispectral refractive topography
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Unveiling three-dimensional sea surface signatures caused by internal solitary waves:insights from the surface water ocean topography mission
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作者 Xudong ZHANG Xiaofeng LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期709-714,共6页
Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global oceans.While remote sensing images have played an essential role in studying ISWs,they mainly exploi... Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global oceans.While remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image information.However,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface information.In this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard SWOT.KaRIN not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height measurements.Our observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation solitons.The surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 m.In contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant advancement.This breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion. 展开更多
关键词 internal solitary wave(ISW) surface water ocean topography(SWOT) ALTIMETER
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Influence of topography on the fine structures of stratospheric gravity waves:An analysis using COSMIC-2 temperature data
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作者 JiaRui Wei Xiao Liu +2 位作者 JiYao Xu QinZeng Li Hong Gao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期497-513,共17页
We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation O... We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation Observing System for Meteorology,Ionosphere,and Climate-2(COSMIC-2)satellite.Owing to the dense sampling of COSMIC-2,in addition to the strong peaks of gravity wave potential energy(GWPE)above the Andes and Tibetan Plateau,we found weak peaks above the Rocky,Atlas,Caucasus,and Tianshan Mountains.The land-sea contrast is responsible for the longitudinal variations of the GWPE in the lower and upper stratosphere.At 40°N/S,the peaks were mainly above the topographic regions during the winter.At 20°N/S,the peaks were a slight distance away from the topographic regions and might be the combined effect of nontopographic GWs and mountain waves.Near the Equator,the peaks were mainly above the regions with the lowest sea level altitude and may have resulted from convection.Our results indicate that even above the local regions with lower sea level altitudes compared with the Andes and Tibetan Plateau,the GWPE also exhibits fine structures in geographic distributions.We found that dissipation layers above the tropopause jet provide the body force to generate secondary waves in the upper stratosphere,especially during the winter months of each hemisphere and at latitudes of greater than 20°N/S. 展开更多
关键词 TOPOGRAPHY fine structures stratospheric gravity waves Constellation Observing System for Meteorology Ionosphere and Climate-2(COSMIC-2) dissipation layers
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Influence of Topography on the Distribution and Structure of Woody Plants in the Senegalese Sahel (Sandy Ferlo)
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作者 Moustapha Bassimbe Sagna Aïssatou Ndong Thiam +5 位作者 Khoudia Niang Oumar Sarr Aly Diallo Sekouna Diatta Daouda Ngom Aliou Guissé 《American Journal of Plant Sciences》 CAS 2024年第1期14-28,共15页
This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considerin... This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considering the different relief units was adopted. Woody vegetation was surveyed using a dendrometric approach. The results obtained show that the flora is dominated by a few species adapted to drought, such as Balanites aegyptiaca (L.) Del., Calotropis procera Ait. and Boscia senegalensis (Pers.). The distribution of this flora and the structure of the ligneous plants are linked to the topography. In the lowlands, the flora is more diversified and the ligneous plants reach their optimum level of development compared with the higher relief areas. In the lowlands, there are a few woody species which, in the past, were indicative of better climatic conditions. These are Anogeissus leiocarpus (DC.), Commiphora africana (A. Rich.), Feretia apodanthera Del., Loeseneriella africana (A. Smith), Mitragyna inermis (Willd.) and Sclerocarya birrea (A. Rich). It is important that their reintroduction into reforestation projects takes account of their edaphic preference. 展开更多
关键词 Woody Plants DISTRIBUTION TOPOGRAPHY Ferlo Senegal
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Study of the ability of SWOT to detect sea surface height changes caused by internal solitary waves
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作者 Hao Zhang Chenqing Fan +1 位作者 Lina Sun Junmin Meng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期54-64,共11页
Surface Water and Ocean Topography(SWOT)is a next-generation radar altimeter that offers high resolution,wide swath,imaging capabilities.It has provided free public data worldwide since December 2023.This paper aims t... Surface Water and Ocean Topography(SWOT)is a next-generation radar altimeter that offers high resolution,wide swath,imaging capabilities.It has provided free public data worldwide since December 2023.This paper aims to preliminarily analyze the detection capabilities of the Ka-band radar interferometer(KaRIn)and Nadir altimeter(NALT),which are carried out by SWOT for internal solitary waves(ISWs),and to gather other remote sensing images to validate SWOT observations.KaRIn effectively detects ISW surface features and generates surface height variation maps reflecting the modulations induced by ISWs.However,its swath width does not completely cover the entire wave packet,and the resolution of L2/L3 level products(about 2 km)cannot be used to identify ISWs with smaller wavelengths.Additionally,significant wave height(SWH)images exhibit blocky structures that are not suitable for ISW studies;sea surface height anomaly(SSHA)images display systematic leftright banding.We optimize this imbalance using detrending methods;however,more precise treatment should commence with L1-level data.Quantitative analysis based on L3-level SSHA data indicates that the average SSHA variation induced by ISWs ranges from 10 cm to 20 cm.NALTs disturbed by ISWs record unusually elevated SWH and SSHA values,rendering the data unsuitable for analysis and necessitating targeted corrections in future retracking algorithms.For the normalized radar cross section,Ku-band and four-parameter maximum likelihood estimation retracking demonstrated greater sensitivity to minor changes in the sea surface,making them more suitable for ISW detection.In conclusion,SWOT demonstrates outstanding capabilities in ISW detection,significantly advancing research on the modulation of the sea surface by ISWs and remote sensing imaging mechanisms. 展开更多
关键词 internal solitary waves Surface Water and Ocean Topography(SWOT) Ka-band radar interferometer(KaRIn) Nadir altimeter(NALT) sea surface height anomaly(SSHA) normalized radar cross section(NRCS)
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DER SPATIAL TURN IN DEN KLASSISCHEN ALTERTUMSWISSENSCHAFTEN(UND SPEZIELL IN DER EPIGRAPHIK)
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作者 Irene Berti 《Journal of Ancient Civilizations》 2024年第1期99-121,125,共24页
Since the 1990s the so-called spatial turn has brought back space and topography into the discussion within historical studies,particular ancient studies.This survey reviews current trends and developments within the ... Since the 1990s the so-called spatial turn has brought back space and topography into the discussion within historical studies,particular ancient studies.This survey reviews current trends and developments within the field and offers some perspectives on possible future developments related to space,material,objects,their agency,and frames. 展开更多
关键词 AGENCY FRAMES material objects space spatial turn TOPOGRAPHY
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FFT and Wavelet-Based Analysis of the Influence of Machine Vibrations on Hard Turned Surface Topographies 被引量:2
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作者 李好胜 吴甦 Hubert Kratz 《Tsinghua Science and Technology》 SCIE EI CAS 2007年第4期441-446,共6页
With hard turning, which is an attractive alternative to existing grinding processes, surface quality is of great importance. Signal processing techniques were used to relate workpiece surface topography to the dynami... With hard turning, which is an attractive alternative to existing grinding processes, surface quality is of great importance. Signal processing techniques were used to relate workpiece surface topography to the dynamic behavior of the machine tool. Spatial domain frequency analyses based on fast Fourier transform were used to analyze the tool behavior. Wavelet reconstruction was used for profile filtering. The results show that machine vibration remarkably affects the surface topography at small feed rates, but has negligible effect at high feed rates. The analyses also show how to control the surface quality during hard turning. 展开更多
关键词 surface topography fast Fourier transform (FFT) WAVELET hard turning machine vibration
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Nature-inspired topographies on hydroxyapatite surfaces regulate stem cells behaviour 被引量:1
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作者 Yogambha Ramaswamy Iman Roohani +5 位作者 Young Jung No Genevieve Madafiglio Frank Chang Furong Zhao Zufu Lu Hala Zreiqat 《Bioactive Materials》 SCIE 2021年第4期1107-1117,共11页
Surface topography is one of the key factors in regulating interactions between materials and cells.While topographies presented to cells in vivo are non-symmetrical and in complex shapes,current fabrication technique... Surface topography is one of the key factors in regulating interactions between materials and cells.While topographies presented to cells in vivo are non-symmetrical and in complex shapes,current fabrication techniques are limited to replicate these complex geometries.In this study,we developed a microcasting technique and successfully produced imprinted hydroxyapatite(HAp)surfaces with nature-inspired(honeycomb,pillars,and isolated islands)topographies.The in vitro biological performance of the developed non-symmetrical topographies was evaluated using adipose-derived stem cells(ADSCs).We demonstrated that ADSCs cultured on all HAp surfaces,except honeycomb patterns,presented well-defined stress fibers and expressed focal adhesion protein(paxillin)molecules.Isolated islands topographies significantly promoted osteogenic differentiation of ADSCs with increased alkaline phosphatase activity and upregulation of key osteogenic markers,compared to the other topographies and the control unmodified(flat)HAp surface.In contrast,honeycomb topographies hampered the ability of the ADSCs to proliferate and differentiate to the osteogenic lineage.This work presents a facile technique to imprint nature-derived topographies on the surface of bioceramics which opens up opportunities for the development of bioresponsive interfaces in tissue engineering and regenerative medicine. 展开更多
关键词 Stem cell BIOMATERIALS BIOCERAMICS Scaffolds MICROPATTERN TOPOGRAPHY
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Multi-Mesh-Scale Approximation of Thin Geophysical Mass Flows on Complex Topographies
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作者 Yih-Chin Tai Jeaniffer Vides +1 位作者 Boniface Nkonga Chih-Yu Kuo 《Communications in Computational Physics》 SCIE 2021年第1期148-185,共38页
This paper is devoted to a multi-mesh-scale approach for describing the dynamic behaviors of thin geophysical mass flows on complex topographies.Because the topographic surfaces are generally non-trivially curved,we i... This paper is devoted to a multi-mesh-scale approach for describing the dynamic behaviors of thin geophysical mass flows on complex topographies.Because the topographic surfaces are generally non-trivially curved,we introduce an appropriate local coordinate system for describing the flow behaviors in an efficient way.The complex surfaces are supposed to be composed of a finite number of triangle elements.Due to the unequal orientation of the triangular elements,the distinct flux directions add to the complexity of solving the Riemann problems at the boundaries of the triangular elements.Hence,a vertex-centered cell system is introduced for computing the evolution of the physical quantities,where the cell boundaries lie within the triangles and the conventional Riemann solvers can be applied.Consequently,there are two mesh scales:the element scale for the local topographic mapping and the vertex-centered cell scale for the evolution of the physical quantities.The final scheme is completed by employing the HLL-approach for computing the numerical flux at the interfaces.Three numerical examples and one application to a large-scale landslide are conducted to examine the performance of the proposed approach as well as to illustrate its capability in describing the shallow flows on complex topographies. 展开更多
关键词 Multi-mesh-scale approach complex topography shallow flows unstructured mesh vertex-centered formulation
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Effect of Mineralized Layer Topographies on Stem Cell Behavior in Microsphere Scaffold
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作者 Jie Hou Huichang Gao +2 位作者 Ying,jun Wang Delin Cheng Xiaodong Cao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第9期971-977,共7页
Modifying substrates through mineralization is a popular way to improve the osteogenic performance. Screening of the best mineralization characteristics on specific substrates for stem cells is meaningful but not full... Modifying substrates through mineralization is a popular way to improve the osteogenic performance. Screening of the best mineralization characteristics on specific substrates for stem cells is meaningful but not fully studied. In this paper, poly(lactic-co-glycolic acid)/hydroxyapatite (PLGA[HA, PH) microsphere scaffolds with superficial pores were fabricated by a low-temperature fusion method. After the mineralization in the 5x stimulated body fluid (SBF) for 0, 7, 12 and 24 h, four mineralized scaffolds (MPH-0, MPH-7, MPH-12 and MPH-24) with different apatite topographies were obtained. It was found that the surface of MPH-7 was evenly decorated with abundant micro-pores, MPH-12 with dense and plain apatite layer, and MPH-24 with small spherical bumps. The responses of mouse bone mesenchymal stem cells (mBMSCs) to the four scaffolds were further studied. The results showed that MPH-7 and MPH-24 had more obvious effects on mBMSCs attachment, proliferation and differentiation than MPH-0 and MPH- 12. This work indicated that to obtain the maximum improvement, the mineralization characteristics had to be carefully chosen. This was noteworthy in the chemical modification of surfaces to form the functionalized scaffolds for bone repair. 展开更多
关键词 Microsphere scaffold Mineralization Topography Cell behavior
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Observation of peripheral refraction in myopic anisometropia in young adults 被引量:1
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作者 Yu-Qin Du Yue-Hua Zhou +3 位作者 Ming-Wei Ding Ming-Xu Zhang Yu-Juan Guo Shan-Shan Ge 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2082-2088,共7页
AIM:To investigate the differences in retinal refraction difference values(RDVs)of adult patients with myopic anisometropia compared with those without myopic anisometropia,and to investigate the relationship between ... AIM:To investigate the differences in retinal refraction difference values(RDVs)of adult patients with myopic anisometropia compared with those without myopic anisometropia,and to investigate the relationship between ocular biometric measurements and relative peripheral refraction.METHODS:This clinical observation study included 130 patients with myopia(-0.25 to-10.00 D)between October 2022 and January 2023 aged between 18 and 40y.The patients were divided into anisometropia(n=63;difference in binocular anisometropia≥1.00 D)and non-anisometropia(n=67;difference in binocular anisometropia<1.00 D)groups accordingly.Ocular biometric measurements were performed by optical biometrics and corneal topography to assess the steep keratometry(Ks),flap keratometry(Kf),axial length(AL),corneal astigmatism(CYL;Ks-Kf),surface regularity index(SRI),surface asymmetry index(SAI),and central corneal thickness(CCT).The RDV was measured at five retinal areas from the fovea to 53 degrees(RDV-0-10,RDV-10-20,RDV-20-30,RDV-30-40,and RDV-40-53),the total RDV(TRDV)of 53 degrees,and four regions,including RDV-superior,RDV-inferior,RDV-temporal,and RDV-nasal.An analysis of Spearman correlation was carried out to examine the correlation between RDV and the spherical equivalent(SE)and ocular biological parameters.RESULTS:Within RDV-20-53,both groups showed relative hyperopic defocus,and the increase in RDV corresponds to the increase in eccentricity.In the myopic anisometropia group,the TRDV,RDV-20-53,RDV-superior,and more myopic eyes had significantly higher RDVtemporal values than less myopic eyes.(P<0.05).In the non-anisometropia group,there was no significant difference in the RDV between the more and less myopic eyes at different eccentricities(P>0.05).There was a negative correlation between SE and TRDV(r=-0.205,P=0.001),RDV-20-53(r=-0.281,-0.183,-0.176,P<0.05),RDV-superior(r=-0.251,P<0.001),and RDV-temporal(r=-0.230,P<0.001),a negative correlation between CYL and RDV-10-30(r=-0.147,-0.180,P<0.05),and a negative correlation between SRI and RDV-0-20(r=-0.190,-0.170,P<0.05).AL had a positive correlation with RDV-20-30(r=0.164,P=0.008)and RDV-temporal(r=0.160,P=0.010).CONCLUSION:More myopic eyes in patients with myopic anisometropia show more peripheral hyperopic defocus.Diopter and corneal morphology may affect peripheral retinal defocus. 展开更多
关键词 MYOPIA ANISOMETROPIA peripheral refraction multispectral refractive topography axial length
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Slope Instability Analysis of the Qiongdongnan Basin in the Northern Part of the South China Sea:Implications for the Risk Evaluation of Deepwater Drilling
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作者 MA Linwei WU Shiguo +5 位作者 LIU Yanrui SUN Jin OUYANG Min LI Qingping QIN Yongpeng WANG Dawei 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期393-409,共17页
The instability of continental slopes damages marine engineering equipment,such as submarine pipelines,resulting in the generation of tsunamis,which endangers the safety of nearshore personnel.Therefore,research on th... The instability of continental slopes damages marine engineering equipment,such as submarine pipelines,resulting in the generation of tsunamis,which endangers the safety of nearshore personnel.Therefore,research on the instability of continental slopes where submarine landslides usually occur is crucial to the risk evaluation of deepwater drilling.Previous studies were mainly based on simplified 2D and 3D models,which extend the 2D model applied on submarine slopes with complex topography.In this study,a numerical model with bathymetric data from the Qiongdongnan Basin was established.Furthermore,3D slope stability analysis and static and dynamic analyses were conducted.The static analysis found two discussions where slopes are most likely to occur.Through the analysis of different seismic forces,the dynamic result showed that an instability area is added to the two positions where the static analysis is unstable.Topography scatters and transmits seismic waves and controls the accumulation and diffusion of seismic energy.3D calculations and analysis revealed that the direction of slope instability is closely related to terrain inclination,slope,terrain effect,and terrain curvature.Data showed that instability situations could not be derived from a single direction or profile data.Such situations are an important factor in slope stability analysis and are critical to the prediction and evaluation of marine geological disasters. 展开更多
关键词 South China Sea submarine landslide slope instability topography curvature topography slope granite
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Functional composition of tall-statured trees underpins aboveground biomass in tropical forests
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作者 Suwash Kunwar Li-Qiu Wang +3 位作者 Maryam Kazempour Larsary Rajeev Chaudhary Puspa Raj Joshi Arshad Ali 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期333-344,共12页
The influences of trait diversity(i.e.,the niche complementarity effect)and functional composition(i.e.,the mass ratio effect)on aboveground biomass(AGB)is a highly debated topic in forest ecology.Therefore,further st... The influences of trait diversity(i.e.,the niche complementarity effect)and functional composition(i.e.,the mass ratio effect)on aboveground biomass(AGB)is a highly debated topic in forest ecology.Therefore,further studies are needed to explore these mechanisms in unstudied forest ecosystems to enhance our understanding,and to provide guidelines for specific forest management.Here,we hypothesized that functional composition would drive AGB better than trait diversity and stem size inequality in the(sub-)tropical forests of Nepal.Using data from 101 forest plots,we tested 25 structural equation models(SEMs)to link elevation,stem DBH inequality,trait diversity(i.e.,trait richness,evenness,dispersion and divergence),functional composition[i.e.,community-weighted of maximum height mean(CWM of Hmax),specific leaf area(CWM of SLA),leaf dry matter content(CWM of LDMC),and wood density(CWM of WD)]and AGB.The best-fitted SEMs indicated that CWM of Hmax promoted AGB while overruling the impacts of trait diversity indices on AGB.However,low trait diversity indices were linked with higher AGB while overruling the effects of CWM of SLA,LDMC and WD on AGB.In addition,AGB decreased with increasing elevation,whereas stem size inequality did not influence AGB.Our results suggest that divergent species’functional strategies could shape AGB along an altitudinal gradient in tropical forests.We argue that forest management practices should include plant functional traits in the management plan for the co-benefits of biodiversity conservation and carbon sequestration that underpins human wellbeing. 展开更多
关键词 Functional traits Mass ratio Niche complementarity Niche overlap TOPOGRAPHY
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