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Three-dimensional reconstruction of systematic histological sections:application to observations on palatal shelf elevation

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International Journal of Oral Science 2021年第2期13卷 183-189页

作者： Weilong Liu Xiaoming Wang Yinuo Wang Yahong Wang Jing Zhang Bing Shi Chenghao Li State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Cleft Lip and Palate Surgery West China School of StomatologySichuan UniversityChengduChina College of Electrical Engineering and information Technology Sichuan UniversityChengduChina

Normal mammalian secondary palate development undergoes a series of processes,including palatal shelf(PS)growth,elevation,adhesion and fusion,and palatal bone formation.It has been estimated that more than 90%of isolated cleft palate is caused by defects associated with the elevation process.However,because of the rapidly completed elevation process,the entire process of elevation will never be easy to clarify.In this article,we present a novel method for three-dimensional(3D)reconstruction of thick tissue blocks from two-dimensional(2D)histological sections.We established multiplanar sections of the palate and tongue in coronal and sagittal directions,and further performed 3D reconstruction to observe the morphological interaction and connection between the two components prior to and during elevation.The method completes an imaging system for simultaneous morphological analysis of thick tissue samples using both synthetic and real data.The new method will provide a comprehensive picture of reorientation morphology and gene expression pattern during the palatal elevation process.

关键词： histological shelf sections

Chemical stability, thermal behavior, and shelf life assessment of extruded modified double-base propellants

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Defence Technology（防务技术） 2018年第1期14卷 70-76页

作者： Sherif Elbasuney Ahmed Fahd Hosam E.Mostafa Sherif F.Mostafa Ramy Sadek School of Chemical Engineering Military Technical College

Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammonium perchlorate/Aluminum), and energetic nitramines(HMX) offered enhanced thrust as well as combustion characteristics. This study is devoted to evaluate the impact of such energetic additives on thermal behavior, chemical stability, and shelf life. Extruded MDB formulations were manufactured by extrusion process. Artificial aging at 80℃ for 28 days was conducted. shelf life assessment was performed using Van't Hoff's equation. Quantification of evolved NOxgases with aging time was performed using quantitative stability tests. MDB formulation based on HMX demonstrated extended service life of 16 years compared with(AP/Al)-MDB which demonstrated 9 years. This finding was ascribed to the reactivity of AP with nitroglycerin with the formation of perchloric acid. Thermal behavior of aged MDB, exhibited an increase in heat released with time; this was ascribed to the autocatalytic thermal degradation during artificial aging. The increase in released heat by 31% was found to be equivalent to evolved NOx gases of 6.2 cm^3/5 g and 2.5 cm^3/1 g for Bergmann-Junk test, and Vacuum stability test respectively. This manuscript shaded the light on a novel approach to quantify evolved NOx gases to heat released with aging time. MDB based on HMX offered balanced ballistic performance,chemical stability, and service life.

关键词： Double-base Chemical stability Thermal behavior Artificial aging shelf life assessment

ddRAD sequencing-based genotyping for population structure analysis in cultivated tomato provides new insights into the genomic diversity of Mediterranean‘da serbo’type long shelf-life germplasm

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Horticulture Research 2020年第1期7卷 1047-1060页

作者： Salvatore Esposito Teodoro Cardi Gabriele Campanelli Sara Sestili María JoséDíez Salvador Soler Jaime Prohens Pasquale Tripodi CREA Research Centre for Vegetable and Ornamental Crops Pontecagnano(SA)Italy CREA Research Centre for Vegetable and Ornamental Crops Monsampolo del Tronto(AP)TrontoItaly Instituto de Conservación y Mejora de la Agrodiversidad Valenciana Universitat Politècnica de València46022 ValenciaSpain

Double digest restriction-site associated sequencing(ddRAD-seq)is a flexible and cost-effective strategy for providing in-depth insights into the genetic architecture of germplasm collections.Using this methodology,we investigated the genomic diversity of a panel of 288 diverse tomato(Solanum lycopersicum L.)accessions enriched in‘da serbo’(called‘de penjar’in Spain)long shelf life(LSL)materials(152 accessions)mostly originating from Italy and Spain.The rest of the materials originate from different countries and include landraces for fresh consumption,elite cultivars,heirlooms,and breeding lines.Apart from their LSL trait,‘da serbo’landraces are of remarkable interest for their resilience.We identified 32,799 high-quality SNPs,which were used for model ancestry population structure and non-parametric hierarchical clustering.Six genetic subgroups were revealed,clearly separating most‘da serbo’landraces,but also the Spanish germplasm,suggesting a subdivision of the population based on type and geographical provenance.Linkage disequilibrium(LD)in the collection decayed very rapidly within<5 kb.We then investigated SNPs showing contrasted minor frequency allele(MAF)in‘da serbo’materials,resulting in the identification of high frequencies in this germplasm of several mutations in genes related to stress tolerance and fruit maturation such as CTR1 and JAR1.Finally,a mini-core collection of 58 accessions encompassing most of the diversity was selected for further exploitation of key traits.Our findings suggest the presence of a genetic footprint of the‘da serbo’germplasm selected in the Mediterranean basin.Moreover,we provide novel insights on LSL‘da serbo’germplasm as a promising source of alleles for tolerance to stresses.

关键词： germplasm breeding shelf

Effect of stratification on current hydrodynamics over Louisiana shelf during Hurricane Katrina

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Water Science and Engineering 2017年第2期10卷 154-165页

作者： Mohammad Nabi Allahdadi Chunyan Li Department of Oceanography and Coastal Sciences College of the Coast and Environment Louisiana State University Baton Rouge 70803 USA

Numerical experiments were conducted using the finite volume community ocean model(FVCOM) to study the impact of the initial density stratification on simulated currents over the Louisiana shelf during Hurricane Katrina. Model results for two simulation scenarios, including an initially stratified shelf and an initially non-stratified shelf, were examined. Comparison of two simulations for two-dimensional(2D) currents,the time series of current speed, and variations of cross-shore currents across different sections showed that the smallest differences between simulated currents for these two scenarios occurred over highly mixed regions within 1 radius of maximum wind(RMW) under the hurricane.For areas farther from the mixed zone, differences increased, reaching the maximum values off Terrebonne Bay. These large discrepancies correspond to significant differences between calculated vertical eddy viscosities for the two scenarios. The differences were addressed based on the contradictory behavior of turbulence in a stratified fluid, as compared to a non-stratified fluid. Incorporation of this behavior in the MellorYamada turbulent closure model established a Richardson number-based stability function that was used for estimation of the vertical eddy viscosity from the turbulent energy and macroscale. The results of this study demonstrate the necessity for inclusion of shelf stratification when circulation modeling is conducted using three-dimensional(3D) baroclinic models. To achieve high-accuracy currents, the parameters associated with the turbulence closures should be calibrated with field measurements of currents at different depths.

关键词： Hurricane Katrina Louisiana shelf Hydrodynamics Baroclinic and barotropic models Stratification

Ancient Changjiang channel system in the East China Sea continental shelf during the last glaciation

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Science China Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3, YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean University of China, Qingdao 266003, China 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique, Qingdao 266003, China 3. Qingdao Institute of Marine Geology, Qingdao 266071, China 4. College of Marine Environment, Ocean University of China, Qingdao 266003, China 5. First Survey Team of Marine Geology, Shanghai Bureau of Petroleum, Shanghai 201208, China College of Marine Geo-science Ocean University of China Qingdao China Shandong Key Laboratory of Sea Floor Resource and Exploration Technique Qingdao China Qingdao Institute of Marine Geology Qingdao China College of Marine Environment Ocean University of China Qingdao China First Survey Team of Marine Geology Shanghai Bureau of Petroleum Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East China Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

Provenance of Sediments Filling a Paleo-Channel that Formed on the Western Yellow Sea Continental shelf During the Last Glacial Period

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Journal of Ocean University of China 2018年第6期17卷 1309-1317页

作者： KONG Xianghuai ZHANG Junqiang BAI Weiming LIU Jian Key Laboratory of Marine Environmental Geology Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China Laboratory of Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Institute of Geology and Paleontology of Linyi University Linyi 276005China Qingdao Geo-Marine Engineering Survey Qingdao 266071China

Several buried paleo-channels are located on the continental shelf of the western Yellow Sea. Research on the paleochannels is significant for both theoretical studies and practical applications. In this paper, we analyse and discuss the mineralogy of sediments in a core(SYS-0803) recovered from a buried paleo-channel on the continental shelf of the western Yellow Sea. The aim is to determine the provenance of sediments that fill the paleo-channel. The heavy mineral assemblage of sediments in the core consists of schistose minerals, common hornblende, epidote, and ilmenite. The light mineral assemblage consists of plagioclase, quartz, lithic fragments, and K-feldspar. Analysis of the compositional maturity of the sand fraction revealed a quartz/feldspar ratio of < 1. A relatively high percentage of smectite is recorded throughout the entire paleo-channel fill, with the greatest percentage in the middle to lower parts. The detrital mineral assemblage and clay mineral content indicate that the paleo-channel sediments were sourced mainly from the Huanghe River during the last glacial period.

关键词： continental shelf of the western Yellow Sea paleo-channel detrital mineral clay mineral heavy mineral assemblage last glacial period sedimentary provenance

Contribution of Mountain River Materials to the Continental shelf off Southeastern Hainan Island Since the Mid-Holocene

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Journal of Ocean University of China 2019年第5期18卷 1123-1129页

作者： TIAN Xu JIANG Zuzhou GAO Wei LIU Zhaoqing LIU Xiling FAN Ying QIN Shengjie JING Chunlei XU Yue LIU Baohua XU Fangjian National Deep Sea Center Qingdao 266237China School of Geosciences China University of PetroleumQingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China China Three Gorges New Energy Co. Ltd.Beijing 100053China China National Offshore Oil Corporation International LimitedBeijing 100027China

The concentrations of rare earth elements(REEs)in the bulk sediment of Core X2,which was collected from southeastern Hainan Island,were analyzed to investigate the relative contributions of various provenance regions since mid-Holocene.The results show that sediments in Core X2 were primarily derived from Hainan Island with lesser amounts from Taiwan and limited input from the Pearl River.Based on the application of quantitative inversion to model the REE data,the average contributions of river materials from southeastern Hainan Island and southwestern Taiwan to the study area were 68%and 32%,respectively.Furthermore,starting at 4.0 kyr BP,the transport of fluvial sediments from Taiwan to the study region increased due to enhanced hydrodynamics in South China Sea(SCS).These results indicate that the contributions of mountain river materials from Hainan Island and Taiwan to the continental shelf of northern SCS are non-negligible.Furthermore,these results demonstrate that mountain rivers can play an important role in the material cycle of continental margins and may feature a greater impact than large river systems in specific continental shelf areas.

关键词： continental shelf South China Sea mid-Holocene rare earth elements provenance

Mosaicing of multiplanar regions through autonomous navigation of off-the-shelf quadcopter

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IET Cyber-Systems and Robotics 2019年第3期1卷 81-92页

作者： Meghshyam G.Prasad Sona Praneeth Akula Anirudh Vemula Sharat Chandran Department of Computer Science and Engineering IIT BombayIndia Robotics Institute Carnegie Mellon UniversityPA 15213USA

The real world is made up of multiplanar and curved surfaces.Imaging such surfaces with an orthographic view using a handheld camera is tiring if the scene encompasses a view larger than the camera field of view.If the scene is geographically beyond the reach of humans,or access to the scene is denied,it is not possible to take such a frontal view of the scene from handheld devices.The advent of inexpensive flying vehicles such as quadcopters enables the orthographic imaging of large surfaces for later analysis either for leisure or serious scientific purposes.However,manual navigation of the quadcopter around such surfaces is tedious and results are not satisfactory.In this paper,the authors present a method for autonomous navigation of a quadcopter for imaging multiplanar surfaces.The proposed method builds on the existing parallel tracking and mapping based approach to create an approximate sparse three-dimensional map of the input scene.Next,the authors determine precise locations for obtaining videos for each bounded plane,and then autonomously manoeuver the quadcopter at these waypoints.This results in an end-to-end application for visualising scenes with an off-the-shelf quadcopter.

关键词： Mosaic autonomous shelf

Temporal-Spatial Variation of Surface Suspended Matter and Controlling Factors in the Inner shelf of the East China Sea in Winter

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Journal of Ocean University of China 2019年第1期18卷 9-19页

作者： MIN Jianxiong LI Guangxue DING Dong QIAO Lulu MA Yanyan YANG Gang ZHANG Yaqi ZHANG Lei LI Shuhao Shanghai Waterway Engineering Design and Consulting Co. Ltd. College of Marine Geosciences Ocean University of China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education Ocean University of China

Based on the observed surface suspended matter in the East China Sea in February 2007 and June 2015, an empirical model was established using L1 b's band 4 data to retrieve surface suspended matter from the Moderate Resolution Imagine Spectroradiometer Terra imagery. The squared correlation coefficient is 0.8358, and the root mean square error is 0.4285 mg L-1. The model reflects the distribution characteristics of surface suspended matter in the inner shelf of the East China Sea. In this paper, the satellite images of the study area were retrieved in January from 2001 to 2015, and the monthly distribution of surface suspended matter were obtained. The inter-annual distribution of the study area is similar, and the concentration of surface suspended matter is higher near the shore than offshore. A large amount of surface suspended matter is transported southeast under the influence of Zhejiang and Fujian coastal current and Taiwan warm current. Only a small amount of surface suspension can reach the Kuroshio area. The surface suspended matter concentration changes obviously near the estuary because of the effect of differences in the flux of the Yangtze River. Meanwhile, winter monsoon, temperature front, El Ni?o events, and other factors affect the distribution of surface suspended matter in 100 m isobath to coastal water but minimally influence the distribution in 100 m isobath to deep sea.

关键词： inner shelf of the East China Sea Moderate Resolution Imagine Spectroradiometer surface suspended matter monthly distribution inter-annual variation