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Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases 被引量:5
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作者 Yi-Fan Chang Jia-Jing Li +4 位作者 Tao Liu Chong-Qing Wei Li-Wei Ma Vladimir N Nikolenko Wei-Long Chang 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1524-1532,共9页
Autophagy is a cellular catabolic process characterized by the formation of double-membrane autophagosomes.Transmission electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and de... Autophagy is a cellular catabolic process characterized by the formation of double-membrane autophagosomes.Transmission electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation.A large number of studies have shown that autophagy is closely related to the digestion,secretion,and regeneration of gastrointestinal(GI)cells.However,the role of autophagy in GI diseases remains controversial.This article focuses on the morphological and biochemical characteristics of autophagy in GI diseases,in order to provide new ideas for their diagnosis and treatment. 展开更多
关键词 AUTOPHAGY morphological study Biochemical characteristics Subcellular structure Transmission electron microscopy Gastrointestinal diseases
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First record of abnormal body coloration in a rockfish Sebastes koreanus(Scorpaenoidei:Sebastidae)from coastal water of China based on morphological characteristics and DNA barcoding
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作者 Ang LI Huan WANG +1 位作者 Changting AN Shufang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期640-646,共7页
The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were c... The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were collected from the coastal waters of Qingdao,China,and the whole body and all fins of them were red.Of the two red-colored rockfish,there were tiny deep red spots on each fin,2 red radial stripes behind and below the eyes and 1 large deep red blotch on the opercula,while the similar stripe and spot patterns are also present in the S.koreanus specimens with normal body coloration.The countable characteristics of the two specimens are in the range of the morphometry of S.koreanus.To further clarify the species identity and taxonomic status of the two specimens,DNA barcode analysis was carried out.The genetic distance between the red-colored rockfish and S.koreanus was 0,and the minimum net genetic distances between the red-colored rockfish and other Sebastes species except for S.koreanus were 3.0%,which exceeds the threshold of species delimitation.The phylogenetic analysis showed that the DNA barcoding sequences of the two red-colored rockfish clustered with the S.koreanus sequences.The above results of DNA barcode analysis also support that the two red-colored rockfish could be identified as the species of S.koreanus.The mechanism of color variation in S.koreanus is desirable for further research and the species could be an ideal model to study the color-driven speciation of the rockfishes. 展开更多
关键词 abnormal body coloration Sebastes koreanus coastal water of China Yellow Sea morphological characteristics DNA barcoding
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Quantitative Study on Morphological Change Characteristics of Tonle Sap Lake Based on DEM
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作者 Yan Huang Yifei Tian +6 位作者 Changwen Li Wu Liu Nan Zhang Haiyang Wang Yue Wu Wanting Feng Yifan Yu 《Open Journal of Modern Hydrology》 CAS 2024年第1期1-13,共13页
Lake is an important part of the natural ecosystem, and its morphological characteristics reflect the capacity of lake regulation and storage, the strength of material migration, and the characteristics of shoreline d... Lake is an important part of the natural ecosystem, and its morphological characteristics reflect the capacity of lake regulation and storage, the strength of material migration, and the characteristics of shoreline development. In most existing studies, remote sensing images are used to quantify the morphological characteristics of lakes. However, the extraction accuracy of lake water is greatly affected by cloud cover and vegetation cover, and the inversion accuracy of lake elevation data is poor, which cannot accurately describe the response relationship of lake landscape morphology with water level change. Therefore, this paper takes Tonle Sap Lake as the research object, which is the largest natural freshwater lake in Southeast Asia. DEM is constructed based on high-resolution measured topographic data, and morphological indicators such as lake area, lake shoreline length, perimeter area ratio, longest axis length, maximum width, shoreline development index, lake shape complexity, compactness ratio and form ratio are adopted to researching the evolution law of high water overflows and low water outbursts quantitatively, and clarifying the variation characteristics of landscape morphology with water level gradient in Tonle Sap Lake. The research results have important theoretical significance for the scientific utilization of Tonle Sap Lake water resources and the protection of the lake ecosystem. 展开更多
关键词 Tonle Sap Lake DEM Geometrical morphology Variation characteristic
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Analysis of morphological characteristics of gravels based on digital image processing technology and self-organizing map 被引量:1
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作者 XU Tao YU Huan +4 位作者 QIU Xia KONG Bo XIANG Qing XU Xiaoyu FU Hao 《Journal of Arid Land》 SCIE CSCD 2023年第3期310-326,共17页
A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and monitoring.However,traditional methods for studying gravels are low-effi... A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and monitoring.However,traditional methods for studying gravels are low-efficiency and have many errors.This study researched the spatial distribution and cluster characteristics of gravels based on digital image processing technology combined with a self-organizing map(SOM)and multivariate statistical methods in the grassland of northern Tibetan Plateau.Moreover,the correlation of morphological parameters of gravels between different cluster groups and the environmental factors affecting gravel distribution were analyzed.The results showed that the morphological characteristics of gravels in northern region(cluster C)and southern region(cluster B)of the Tibetan Plateau were similar,with a low gravel coverage,small gravel diameter,and elongated shape.These regions were mainly distributed in high mountainous areas with large topographic relief.The central region(cluster A)has high coverage of gravels with a larger diameter,mainly distributed in high-altitude plains with smaller undulation.Principal component analysis(PCA)results showed that the gravel distribution of cluster A may be mainly affected by vegetation,while those in clusters B and C could be mainly affected by topography,climate,and soil.The study confirmed that the combination of digital image processing technology and SOM could effectively analyzed the spatial distribution characteristics of gravels,providing a new mode for gravel research. 展开更多
关键词 self-organizing map digital image processing morphological characteristics multivariate statistical method environmental monitoring
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Morphological characteristics and atomic evolution behavior of nanojoints in Ag nanowire interconnect network
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作者 Jianlei Cui Xiaoying Ren +5 位作者 Xuesong Mei Zhengjie Fan Chenchen Huang Zhijun Wang Xiaofei Sun Wenjun Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第2期254-264,共11页
Ag nanowires(AgNWs)have shown great application value in the field of flexible electronics due to their excellent optical and electrical properties,and the quality of its joints of AgNWs in the thin film network direc... Ag nanowires(AgNWs)have shown great application value in the field of flexible electronics due to their excellent optical and electrical properties,and the quality of its joints of AgNWs in the thin film network directly plays a key role in its performance.In order to further improve the joint quality of AgNWs under thermal excitation,the thermal welding process and atomic evolution behavior of AgNWs were investigated through a combination of in situ experimental and molecular dynamics simulations.The influence of processing time,temperature,and stress distribution due to spatial arrangement on nanojoints was systematically explored.What is more,the failure mechanisms and their atomic interface behavior of the nanojoints were also investigated. 展开更多
关键词 Ag nanowires NANOCONTACTS morphological characteristics atomic configuration MD simulation
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Morphological Characteristics, Ecological Habits and Utilization Value of Acrossocheilus fasciatus
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作者 Xia Yunxing Lu Wenxuan 《Animal Husbandry and Feed Science》 CAS 2023年第1期36-38,共3页
Acrossocheilus fasciatus is a small omnivorous benthic fish widely distributed in the middle and upper reaches of mountain streams and small rivers in hilly and mountainous areas,suitable for stocking in the forks of ... Acrossocheilus fasciatus is a small omnivorous benthic fish widely distributed in the middle and upper reaches of mountain streams and small rivers in hilly and mountainous areas,suitable for stocking in the forks of reservoirs,streams or rivers,and artificial culture in larger ponds and eel farms,etc.The paper describes the morphological characteristics,ecological habits,geographic distribution,resources and utilization value of A.fasciatus,in order to provide scientific and practical reference information for individuals or enterprises interested in A.fasciatus culture and promote the sustainable development of A.fasciatus culture industry. 展开更多
关键词 Acrossocheilus fasciatus morphological characteristics Ecological habits Geographical distribution Resource and utilization value
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Morphological Characteristics Analysis of 11 Broom Sorghum Varieties 被引量:1
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作者 乌艳红 李志明 +8 位作者 辛晓平 孙德欣 吕宁 乌仁图亚 娜日娜 赵建平 王军 韩晓华 李峰 《Agricultural Science & Technology》 CAS 2009年第1期15-18,42,共5页
[Objective] To provide a theoretical basis for high-yield breeding of broom sorghum.[Method] Using 11 kinds of broom sorghum collected at home as research objects, the differences in morphological characteristics of b... [Objective] To provide a theoretical basis for high-yield breeding of broom sorghum.[Method] Using 11 kinds of broom sorghum collected at home as research objects, the differences in morphological characteristics of broom sorghum were compared through the survey of some indicators, such as plant height, tillering, inflorescence, stem node, stem-leaf ratio, yield, and so on. [Result] The 11 kinds of broom sorghum were different in morphological characteristics with large amplitude of plant height; zygl-1, zygl-6, zygl-8 and zygl-9 were appropriate for fixed broom type; zygl-9 had the highest integrated production. [Condusion] The study laid the foundation for further exploring breeding, cultivation and promotion of broom sorghum. 展开更多
关键词 Broom sorghum morphological characteristic ANALYSIS
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Morphological comparison and molecular marker screening of three Skeletonema species found in Changjiang(Yangtze)River Basin
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作者 Jingwen HU Yuxin YI +4 位作者 Zhengxin YANG John Patrick KOCIOLEK Pan YU Quanxi WANG Qingmin YOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期923-942,共20页
In our recent investigations of diatom diversity,we studied three species,namely,Skeletonema costatum,Skeletonema subsalsum,and Skeletonema potamos.Although they have been found frequently in Changjiang(Yangtze)River ... In our recent investigations of diatom diversity,we studied three species,namely,Skeletonema costatum,Skeletonema subsalsum,and Skeletonema potamos.Although they have been found frequently in Changjiang(Yangtze)River Basin,their morphological and molecular identification is difficult in taxonomy.Therefore,to integrate morphological and molecular biological approaches,we compared systematically their morphological characters and performed phylogenetic analysis.Twelve strains of Skeletonema were collected and isolated from Shanghai and Jiangsu,China,and their morphological characteristics were examined by light microscopy(LM)and the scanning electron microscopy(SEM).Based on morphological comparison,we determined that S.potamos is easy to distinguish from the other two species.The heavily silicified areolae,undulated or cleft distal ends of terminal fultoportula processes(TFPPs),absence of basal pores of fultoportula processes(FPPs),the rootlike protrusions of FPPs,and no interlocking connection are the stable characteristics that can be used to identify S.potamos.However,there are only two features that can distinguish S.costatum from S.subsalsum,namely the location of terminal rimoportulae(TRPs)and the distal shape of TFPPs.In addition,we amplified and sequenced nine common genetic markers from the strains,from which 101 sequences were obtained,constructed phylogenetic trees based on the nine genes and evaluated that seven genes can be used to identify S.potamos,and revealed that S.subsalsum is the closest known relative of S.costatum,and only ATP synthetase beta-subunit gene(atp B)is able to distinguish them from each other,which strongly support that it is an effective molecular marker for Skeletonema.This work provided a theoretical basis for the taxonomic study of Skeletonema. 展开更多
关键词 SKELETONEMA Changjiang River morphological change distinguishing morphological characteristics molecular marker
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Morphological and cytological assessments reveal pollen degradation causes pollen abortion in cotton cytoplasmic male sterility lines
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作者 PEI Qingyu LIU Jinshan +10 位作者 GUO Chunping MA Xiaomei LIU Xiaoyan YOU Chunyuan LIN Hairong LI Zhibo ZHAO Ruihai ZHU Bo WU Yuanlong PAN Zhenyuan NIE Xinhui 《Journal of Cotton Research》 CAS 2024年第3期266-276,共11页
Background Understanding the mechanism of male sterility is crucial for producing hybrid seeds and developing sterile germplasm resources.However,only a few cytoplasmic male sterility(CMS)lines of cotton have been pro... Background Understanding the mechanism of male sterility is crucial for producing hybrid seeds and developing sterile germplasm resources.However,only a few cytoplasmic male sterility(CMS)lines of cotton have been produced due to several challenges,like inadequate variation of agronomic traits,incomplete sterility,weak resilience of restorer lines,and difficulty in combining strong dominance.Therefore,the morphological and cytological identification of CMS in cotton will facilitate hybrid breeding.Results Two F_(2) segregating populations of cotton were constructed from cytoplasmic male sterile lines(HaA and 01A,maternal)and restorer lines(HaR and 26R,paternal).Genetic analysis of these populations revealed a segregation ratio of 3:1 for fertile to sterile plants.Phenotypic analysis indicated no significant differences in traits of flower bud development between sterile and fertile plants.However,sterile plants exhibited smaller floral organs,shortened filament lengths,and anther atrophy on the flowering day in comparison with the fertile plants.When performed scanning electron microscopy(SEM),the two F_(2) populations revealed morphological variations in the anther epidermis.Cellular analysis showed no significant differences in pollen development before pollen maturation.Interestingly,between the pollen maturation and flowering stages,the tapetum layer of sterile plants degenerated prematurely,resulting in abnormal pollen grains and gradual pollen degradation.Conclusion The results of this study suggest that fertility-restoring genes are controlled by a single dominant gene.Sterile plants exhibit distinctive floral morphology,which is characterized by stamen atrophy and abnormal anthers.Pollen abortion occurs between pollen maturity and flowering,indicating that premature tapetum degradation may be the primary cause of pollen abortion.Overall,our study provides a theoretical basis for utilizing CMS in hybrid breeding and in-depth investigation of the dominant configuration of cotton hybrid combinations,mechanisms of sterility,and the role of sterile and restorer genes. 展开更多
关键词 COTTON Cytoplasmic male sterility Genetic analysis morphological characteristics Pollen development
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Building Morphological Characteristics and Their Effect on the Wind in Beijing 被引量:6
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作者 苗世光 李萍阳 王晓云 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1115-1124,共10页
An urban boundary layer model (UBLM) is improved by incorporating the effect of buildings with a sectional drag coefficient and a height-distributed canopy drag length scale. The improved UBLM is applied to simulate... An urban boundary layer model (UBLM) is improved by incorporating the effect of buildings with a sectional drag coefficient and a height-distributed canopy drag length scale. The improved UBLM is applied to simulate the wind fields over three typical urban blocks over the Beijing area with different height-towidth ratios. For comparisons, the wind fields over the same blocks are simulated by an urban sub-domain scale model resolving the buildings explicitly. The wind fields simulated from the two different methods are in good agreement. Then, two-dimensional building morphological characteristics and urban canopy parameters for Beijing are derived from detailed building height data. Finally, experiements are conducted to investigate the effect of buildings on the wind field in Beijing using the improved UBLM. 展开更多
关键词 building morphological characteristics urban boundary layer model urban canopy model
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The morphological characteristics of gully systems and watersheds in Dry-Hot Valley, SW China 被引量:1
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作者 Zhen Xu Fachao Qin +4 位作者 Bin Zhang Qingchun Deng Hui Liu Jie Jin Liangtao Shi 《Acta Geochimica》 EI CAS CSCD 2018年第6期854-866,共13页
Gully systems and watersheds are geomorphic units with clear boundaries that are relatively independent of basin landscapes and play an important role in natural geography. In order to explore the morphological charac... Gully systems and watersheds are geomorphic units with clear boundaries that are relatively independent of basin landscapes and play an important role in natural geography. In order to explore the morphological characteristics of gully systems and watersheds in the Dry-Hot Valley [South West(SW) China], gullies are interpreted from online Google images with high resolution and watersheds are extracted from digital elevation model at a scale of 1:50,000. The results show that:(1) There are17,382 gullies(with a total area of 1141.66 km2) and 42 watersheds in the study area.(2) The average gully density of the study area(D) is 4.29 km/km2, gully frequency(F) is 14.39 gullies/km2, the branching ratio(B) is 5.13, the length ratio(L) is 3.12, and the coefficient of the main and tributary gullies(M) is 0.06. The degree of gully erosion isstrong to extremely strong, the main development intensity of gully erosion ranges from intense to moderate, and the type of gully system is tributary.(3) The watershed areas(A) are between 0.39 and 96.43 km2, the relief ratio(R) is from 0.10 to 0.19, the circularity ratio(C) is from 0.30 to0.83, the texture ratio(T) is from 0.82 to 39.35, and the dominant geomorphological texture type is fine.(4) There is a quantitative relationship between F and D:F = 0.624 D2(R =0.84) and T is closely related to D, F, M(R2[ 0.7). A,R and C are related to M(R2[ 0.5). The development of gully systems is the result of coupling effects between multiple factors. In this area, the degree of erosion and the condition of the main and tributary gullies can be controlled by the degree of topographic breakage in the watershed, which provides some theoretical basis for the evaluation of gully erosion by the latter. In addition, the scale, relief, and shape have a significant impact on the locations of the main and tributary gullies. For tributary gullies, attention should be paid to the interception and control of runoff and sediment in the small confluence branches in order to prevent gully expansion and head advance. These features can inform the development of targeted measures for the control of soil erosion. 展开更多
关键词 morphological characteristics Quantitative RELATIONSHIPS GULLY system WATERSHED Dry-Hot VALLEY
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Morphological Characteristics of Cambodia Mekong Delta and Tonle Sap Lake and Its Response to River-Lake Water Exchange Pattern 被引量:2
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作者 Zhaoming Xu Changwen Li +4 位作者 Anqiang Li Zhongqiong You Wei Yao Yongsheng Chen Liyao Huang 《Journal of Water Resource and Protection》 2020年第4期275-302,共28页
Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversit... Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversity. The river-lake relationship between Mekong River and Tonle Sap Lake is unique and has always been a major focus in the international community. The land terrain and under-water topography were used to analyze the morphological characteristics of Cambodia Mekong Delta and Tonle Sap Lake. Long series of hydrological data of river-lake controlling stations were used to analyze the water level variation characteristics and water volume exchange pattern between Mekong River and Tonle Sap Lake, and the response relationship to river-lake morphological characteristics were also researched. The results show that: Cambodia Mekong Delta and Tonle Sap Lake Area is low-lying and flat with gentle channel gradient and water surface gradient, making the relationship between water level and area (or volume) smooth. The channel storage capacity of Mekong River and Tonle Sap River is not enough compared to the inflow, so vast flooding plain is extremely prone to be inundated, making the flood relationships between the left and right banks become very complicated. Tonle Sap Lake is a seasonal freshwater lake with water flowing in and flowing out, and the timing and intensity of water exchange with Mekong River are closely related to the water flow resistance at the exit section of Tonle Sap Lake and the cross-sectional area of Tonle Sap River, which can be reflected by the river-lake water level difference and the water level of Tonle Sap River. Affected by the river-lake morphological characteristics, the water exchange intensity between Mekong River and Tonle Sap Lake is great. Tonle Sap Lake not only stores 14.4% of flood volume (39.7 billion m3) from the Mekong River every year, but also supplies 29.7% of dry water (69.4 billion m3) to the Mekong River. Influenced by the adjustment of the floodplain, the water level fluctuation of Mekong River and Tonle Sap Lake is slow, and the rising and droop rates of water level are positively correlated with the floodplain storage area. The research results will help to understand the relationship mechanism between Mekong River and Tonle Sap Lake and provide a scientific basis for the comprehensive governance of Cambodia Mekong Delta and Tonle Sap Lake Area. 展开更多
关键词 Tonle Sap LAKE Mekong RIVER morphological characteristic River-Lake RELATIONSHIP Water EXCHANGE PATTERN RESPONSE RELATIONSHIP
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Morphological Characteristics of Precipitation Areas over the Tibetan Plateau Measured by TRMM PR 被引量:2
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作者 Yilun CHEN Aoqi ZHANG +2 位作者 Yunfei FU Shumin CHEN Weibiao LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第4期677-689,共13页
The multidimensional morphological characteristics(including scale, horizontal shape and 3 D morphology) of precipitation areas over the Tibetan Plateau in summer were studied using 15 years(1998–2012) of observation... The multidimensional morphological characteristics(including scale, horizontal shape and 3 D morphology) of precipitation areas over the Tibetan Plateau in summer were studied using 15 years(1998–2012) of observational data from the precipitation radar onboard the Tropical Rainfall Measuring Mission satellite. As the scale of the precipitation area increased from 20 to 150 km, the near-surface rain rate(RRav) of the precipitation area increased by up to 78%(from ~1.12 to ~2 mm h~(-1)). Linear precipitation areas had the lowest median RRav(~1 mm h~(-1) over the eastern Tibetan Plateau),whereas square-shaped precipitation areas had the highest median RRav(~1.58 mm h~(-1) over the eastern Tibetan Plateau).The 3D morphology was defined as the ratio of the average vertical scale to the average horizontal scale, where a large value corresponds to thin and tall, and a small value corresponds to plump and short. Thin-and-tall precipitation areas and plump-and-short precipitation areas had a greater median RRav, whereas the precipitation areas with a moderate 3D morphology had the lowest median RRav. The vertical structure of the precipitation-area reflectivity was sensitive to both size and 3D morphology, but was not sensitive to the horizontal shape. The relationship between RRav and the morphological characteristics was most significant over the southern slopes of the Tanggula Mountains and the Tibetan Plateau east of 100°E. The morphological characteristics of precipitation areas are therefore closely related to the intensity of precipitation and could potentially be used to forecast precipitation and verify numerical models. 展开更多
关键词 precipitation areas morphological characteristics Tibetan Plateau TRMM PR
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Morphological characteristics in the area off eastern Taiwan Island and their tectonic implications 被引量:1
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作者 LIUBaohua ZHENGYanpeng +2 位作者 WUJinlong HANGuozhong ZHANGDeyu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第3期449-461,共13页
On the basis of bathymetric data and other geological and geophysical data obtained during the first survey conducted by Chinese Mainland in the area off eastern Taiwan Island from May to June in 2000, the morphologic... On the basis of bathymetric data and other geological and geophysical data obtained during the first survey conducted by Chinese Mainland in the area off eastern Taiwan Island from May to June in 2000, the morphological features of the region, the tectonic control to the seafloor topography and their tectonic implication are studied and discussed. The results have revealed that both the slope zone of the Ryukyu arc and the Ryukyu Trench present a typical morphotectonic characteristics controlled by the trench-arc system in the West Pacific Ocean. At the slope of eastern Taiwan Island the isobathic lines parallel to the coastline and distribute densely in nearly N-S direction and the slope gradient of topography is large. Such a unique feature is attributed to the collision of the Luzon arc and Eurasia continent. In the Huatung Basin, turbidity fans and submarine canyons are well developed, the formations of which are mainly related to the steep topography of the slope of the Luzon arc and the abundant supply of sediments. These submarine canyons are controlled by basement highs and strike-slip faults. On eastern side and western side of the Gagua Ridge, both the water depth and morphological features are different, but the basement of Gagua Ridge belongs to the Huatung Basin. The eastern side of the Gagua Ridge (123°12′E) corresponds to the boundary of two plates with different ages. In the West Philippine Basin, linear ridges and troughs in a NW trending are identified, which are dissected by a NE trending transform fault. According to the seafloor topography features, the direction of the transform fault and the magnetic anomaly lineations, the seafloor of this region was formed during 60-45 Ma B. P. when the West Philippine Basin was spreading along NE-SW relative to the present orientation. 展开更多
关键词 Taiwan Island morphological characteristics tectonic implications
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Observation of Morphological Characteristics on Rhbdophaga SP
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作者 张玉美 姚骏 +2 位作者 潘学峰 郭永生 林华峰 《Agricultural Science & Technology》 CAS 2011年第11期1649-1652,共4页
[Objective] The research aimed at describing morphological characteristics of Rhbdophaga SP. [Method] The morphological characteristics of gall midges (Rhbdophaga SP) on salix, which distributed along lake area of H... [Objective] The research aimed at describing morphological characteristics of Rhbdophaga SP. [Method] The morphological characteristics of gall midges (Rhbdophaga SP) on salix, which distributed along lake area of Huaihe river in Huoqiu Country, were observed from March, 2008 to June, 2010, and larval instars, larval duration and pupal duration were also divided. [Result] Morphological characteristics of Rhbdophaga SP were described in detail, and the larvae were divided into three instars based on the development and molting with the greatly varied shapes and sizes. The pupa is free pupa, and the development of a pupa was divided into four stages, pre-pupal stage, early pupal stage, mid-pupal stage and late puapl stage. [Conclusion] Results were referential for further research of Rhbdophaga SP. 展开更多
关键词 Salix integra Linn Rhbdophaga SP morphological characteristics
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Analysis of genotype differences of rice response to low Zn^(2+) activity and some morphological characteristics 被引量:5
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作者 WANG Renmin, Dept of Agro YANG Xiao’e and YANG Yuai, Dept of Agri Chemistry, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1998年第3期11-12,共2页
Zinc deficiency is one of the most widespreadmicro-nutritional disorder for rice. To solve the problem, screening Zn-efficient cultivars isan available method and understanding geno-
关键词 Analysis of genotype differences of rice response to low Zn activity and some morphological characteristics root
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Morphological Characteristics of the Long-legged Chafer Hoplia spectabilis Medvedev(Coleoptera: Scarabaeoidea) at Various Developmental Stages
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作者 Guo Jianpu Nong Xiangqun Wang Feng 《Plant Diseases and Pests》 CAS 2015年第3期25-29,共5页
The long-legged chafer Hoplia spectabilis Medvedev was described in 1952. Its occurrence was rarely reported and the document about its morphological details was not found. However, the chafer did frequently break out... The long-legged chafer Hoplia spectabilis Medvedev was described in 1952. Its occurrence was rarely reported and the document about its morphological details was not found. However, the chafer did frequently break out at Buha River valley in Tianjun county, Qinghai province, China since 2005. In this paper, we present a comprehensive description and illustrations of morphological characteristics of H. spectabilis from local collection, including developmental stages of adult, egg, larva and pupa. Among them, characteristics of the larva and pupa, the male genitalia as well as the difference between male and female are described for the first time. The morphological data will be quite useful for identification and characterization of the chafer, a poorly known species. It will also be an important basis for the chafer control when it breaks out. 展开更多
关键词 Hoplia spectabilis Medvedev morphological characteristics ADULT EGG Larva PUPA
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Factors Influencing the Morphological Characteristics of Village Chickens’ Genetic Resources in the Abu-Dhabi Emirate, UAE
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作者 Mohammad J. Tabbaa Hussein H. Hassanin 《Open Journal of Animal Sciences》 2018年第1期87-103,共17页
The study was accomplished to identify the characteristics of village chickens’ (VCs) genetic resources in the Abu-Dhabi Emirate of United Arab Emirate (UAE) and to study factors affecting these characteristics. Each... The study was accomplished to identify the characteristics of village chickens’ (VCs) genetic resources in the Abu-Dhabi Emirate of United Arab Emirate (UAE) and to study factors affecting these characteristics. Each bird was individually observed, identified, measured and characterized of thirteen VCs pure breeds and crossbreds. The overall VCs had normal feather morphology (95.1%) and distribution (77%). Except for Fayomi chickens which were 100% mottled, no specific plumage pattern was found. Almost 52% of the VCs had white skins. Six different colors were reported for the shanks and maximized for white shanks (34.3%). Large breasts (46%) were more available. The predominant plumage color was mixed colors (37.5%). Face size tended to be small (42.8%) to medium (40.4%). More brown (48.9%) then orange (27.3%) eyes were found. Dark (49.7%) beaks were more available than white (28.6%) or yellow (21.7%) beaks. The distribution of wattle colors was similar to that of ear-lob colors with some variation. Small wattles (41.9%) were most available. Single comb (82.4%) is the most available;11 other types and one with no comb were represented with low frequencies. In the whole sample, red and white combs (56.7%) were the most available;however, plain red (23.8%) and red and black (15.5%) were represented. Results of factors influence showed that body weight was high significantly (P < 0.01) influenced by the interaction between both breed and region and breed and sex. Significant (P < 0.01) influence of interaction was observed between breed and location on body length, wing span and shank length. The interaction between breed and sex only significantly (P < 0.01) influenced shank length. Though, all main effects of breed, sex and region significantly (P < 0.01) influenced continuous measures. Most morphological characteristics were significantly (P < 0.01) different among breeds. This study reported the morphological characteristics of the different VCs breeds kept in Abu-Dhabi Emirate, which considered the scientific base for future implementing of conservation and/or genetic improvement programs. 展开更多
关键词 Body WEIGHT BREEDS morphological characteristics UAE VILLAGE CHICKENS
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Morphological Characteristics and Nutrient Content of Fine Roots of 2-Year-Old and 3-Year-Old Eucalyptus grandis Plantation
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作者 Xiaoyu DUAN Xianwei LI +2 位作者 Liuling ZHOU Weishuang WANG Hui CHEN 《Agricultural Biotechnology》 CAS 2012年第6期9-14,共6页
[ Objective] This study aimed to explore the morphological characteristics and nutrient content of f'me roots of 2-year-old and 3-year-old Euca/yptus grand/s plantation and investigate the correlation. [ Method] Fine... [ Objective] This study aimed to explore the morphological characteristics and nutrient content of f'me roots of 2-year-old and 3-year-old Euca/yptus grand/s plantation and investigate the correlation. [ Method] Fine roots of 2-year-old and 3-year-old Eucalyptus grandis plantation were collected as experimental materials, to determine the root diameter (D), root length (L), specific root length (SRL) and contents of major nutrient elements N, P, K, Ca, Mg and C of fine roots (level 1 -5), study the morphological characteristics and major nutrient element content and investigate the correlation. [ Result] The results showed that morphological differences of fine roots ( level 1 - 5 ) of Eucalyptus grandis plantation were great with the increase of root order, to be specific, D and L increased and SRL decreased with the increasing root order; SRL, L and D of 3-year-old Eucalyptus grauclis plantation were greater than those of 2-year-old Euca/yptus grand/s plantation. Contents of N, Ca, Mg and C of fine roots of 2-year-old and 3-year-old Eucalyptus grandis plantation showed consistent orders with the increase of root order: N and Mg contents were reduced, while Ca and C contents were enhanced; P and K contents varied with different forest ages; both 2-year-old and 3-year- old Eucalyptus grandis showed an order of C 〉 K 〉 Ca (Mg) 〉 N. Major nutrient element content and morphological characteristics of Eucalyptus grand/s fine roots (level 1 -5 ) were extremely significantly correlated (P 〈0.01 ), SRL, L and D could be adopted as reference indices to evaluate nutrient status of Eucalyptus grand/s. Required nutrients and fine root morphology of Eucalyptus grandis plantation changed with the increase of forest age, and the nutrient cycling and energy flow patterns also changed; major nutrient dements in fine roots of 2-year-old and 3-year-old Eucalyptus grandis plantation transferred in a different order from the growth order, therefore N fertilizer could be applied to improve the growth of fine roots. [ Condusion] This study laid the foundation for understanding the fine root morphology and nutrient variation pattern of Eucalyptus grandis plantation and enriching the response and adaptation mechanism theory of roots to environment, pos- sessing important reference significance for the sustainable development of Eucalyptus grand/s plantation. 展开更多
关键词 Eucalyptus grandis Fine root Root order Nutrient elements morphological characteristics
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Morphological characteristics of tree crowns of Cunninghamia lanceolata var. Luotian
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作者 Yezhou Xu Chaoqun Du +4 位作者 Guowei Huang Zhenfang Li Xiangyang Xu Jingjin Zheng Chu Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期837-856,共20页
The structural characteristics of the tree crowns of Cunninghamia lanceolata var. Luotian(herein, Luotian), a natural variety of C. lanceolata(Chinese-fir, herein Lanceolata) in China, were analyzed using trunk and br... The structural characteristics of the tree crowns of Cunninghamia lanceolata var. Luotian(herein, Luotian), a natural variety of C. lanceolata(Chinese-fir, herein Lanceolata) in China, were analyzed using trunk and branch measurements and biomass determinations. Samples from two typical cultivated varietal populations were collected, including twenty-six 15–23-year-old trees of Luotian from a plantation, and nine 16–23-year-old trees of Lanceolata. Our results show that Luotian and Lanceolata samples differed significantly in crown structure, morphological indices, and biomass:(1) the oldest live branches on Luotian trees were 5–6 years old and 8–11 years old on Lanceolata. The ages of the live branches were not affected by the ages of the Luotian trees, while live branch ages increased with ages of Lanceolata trees;(2) the maximumbranching order of Luotian was level two. Compared to Lanceolata, the average number of first-order lateral branches(i.e., branches emerging from the trunk) and the number of first-order lateral branch whorls per sample tree were 12.9% and 32.2% lower, respectively, in Luotian.However, the average number of branches within a single whorl was 21.8% greater in Luotian;the average number of branch whorls at crown height was 51.1% greater. Thus,the Luotian variety has thicker branches;(3) the average lateral branch angles in Luotian and Lanceolata sample trees were 105.2° and 61.4°, respectively. The branch angles in 53.0% of lateral branches on Luotian ranged from105° to 135°, but 30° to 90° in 96% of the lateral branches on Lanceolata. Within the same crown layer, the average branch angle was 1.6–2.2 times greater in Luotian, and the angle was directly proportional to crown thickness;(4) the average base diameter and branch length on Luotian were1.3 cm and 75.8 cm, respectively, and 1.6 cm and112.2 cm for Lanceolata. For individual trees, branch growth differed significantly(p < 0.01) between Luotian and Lanceolata. However, the lateral branches grew at a similar rate among Luotian trees of different ages;(5) the average height to the lowest live branch on Luotian was128.3% greater than on Lanceolata, resulting in a significant difference(p < 0.01) in crown size. Compared to the crowns on Lanceolata, the Luotian crowns were 45.3%higher and 41.1% wider, and the surface area, volume, and growth of the crown were 27.0%, 11.4%, and 2.4 times greater than for Lanceolata, respectively;and,(6) the biomass of Luotian and Lanceolata sample trees also differed significantly. The mean crown, branch, and leaf biomass for Luotian was 40.0%, 25.2%, and 54.1% of those for Lanceolata, respectively. However, the leaf biomass in each layer of the Luotian crown was higher thanthat of Lanceolata, and leaf biomass increased with crown thickness. 展开更多
关键词 Cunninghamia lanceolata VAR Luotian Cunninghamia lanceolata TREE CROWN morphological characteristics VARIATION
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