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Species limits in the Elegant Pitta (Pitta elegans) complex from Wallacea based on bioacoustic and morphometric analysis 被引量:1
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作者 Arya Y.Yue Elize Y.X.Ng +1 位作者 James A.Eaton Frank E.Rheindt 《Avian Research》 CSCD 2020年第4期421-432,共12页
Background:The Elegant Pitta(Pitta elegans)complex displays a remarkable diversity of morphological and bioacoustic traits across five taxa currently recognized as subspecies.They differ in plumage characteristics(suc... Background:The Elegant Pitta(Pitta elegans)complex displays a remarkable diversity of morphological and bioacoustic traits across five taxa currently recognized as subspecies.They differ in plumage characteristics(such as red versus black belly patches;supercilium color and extent;and white versus black throats),in lifestyle(resident versus migratory)and in vocalizations.We investigated the morphological,bioacoustic and ecological differences across all taxa after recent studies demostrated the importance of these traits in recognizing biological species limits across pittas.Methods:Morphometric analysis was carried out by measuring tarsus,wing,tail and bill lengths of 15 specimens at the Natural History Museum,UK,and plumages were inspected across 106 unique individuals from four different repositories.Bioacoustic analysis was based on 134 range-wide sound recordings.Two types of calls,territorial calls and alarm calls,were analyzed using different sets of parameters.Principal component analysis and the Isler Criterion were applied to the measurements.Playback trials were conducted to explore the levels of response of each taxon to the call types of the other taxa.Results:The territorial call of concinna exhibits a distinct two-element motif,while elegans,maria and virginalis utter a three-element motif in which the first two elements are given in quick succession.On the other hand,vigorsii,produces both two-element and three-element motifs with longer breaks in between elements.As further corroborated by the playback trials,the three taxa elegans,virginalis and maria form a tight vocal cluster,whereas each concinna and vigorsii are distinct.The alarm call turned out to be less diagnostic even though most taxa did roughly separate into different vocal clusters.Morphometric analysis failed to produce strong differences,but plumage distinctions among multiple taxa are pronounced.Conclusions:We suggest splitting the Elegant Pitta into three biological species based on bioacoustic and—less so—plumage evidence:(1)Temminck’s Elegant Pitta P.elegans(including subspecies elegans,virginalis and maria),(2)Wallace’s Elegant Pitta P.concinna(monotypic),and(3)Banda Elegant Pitta P.vigorsii(monotypic). 展开更多
关键词 Bioacoustic analysis Elegant Pitta morphometric analysis Pitta elegans Territorial calls
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Morphometric analysis of sand fly(Diptera:Psychodidae:Phlebotominae), Sergentomyia anodontis Quate and Fairchild, 1961, populations in caves of southern Thailand
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作者 Nattapong Maneeroth Nawee Noonanant +1 位作者 Kanaphot Thongkhao Theerakamol Pengsakul 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第9期415-422,共8页
Objective:To determine the morphological characteristics of variations in populations of female adult sand fly,Sergentomyia anodontis Quate and Fairchild,1961 in caves in southern Thailand using morphometric analysis.... Objective:To determine the morphological characteristics of variations in populations of female adult sand fly,Sergentomyia anodontis Quate and Fairchild,1961 in caves in southern Thailand using morphometric analysis.Methods:A total of 107 female Sergentomyia anodontis were isolated from 651 sand flies captured by CDC light traps overnight in caves in Surat Thani,Nakhon Si Thammarat,Satun and Songkhla provinces from February to December 2017.Measurement of 23 external and internal morphological characteristics was conducted.Data were tested with preliminary statistics(Kolmogorov-Smirnov test,Levene’s test and Box’s test of equality of covariance matrices)and by one-way ANOVA or Kruskal-Wallis test.Measurements were analyzed using canonical discriminant analysis.Results:There were 11 morphological characteristics with high variability while two characteristics exhibited low variation.The sand fly populations from Nakhon Si Thammarat,Satun and Songkhla provinces were very similar but were separate from that in Surat Thani province based on canonical discriminant analysis data.This indicates that the morphological variation founding is a result of the diversity of habitats in each population and the geographic features of caves in each area,such as their altitude above sea level.Conclusions:There is a certain variation in the morphology of Sergentomyia anodontis sand flies at the population level which may be used for future classification of sand flies. 展开更多
关键词 morphometric analysis LEISHMANIASIS Sergentomyia anodontis Canonical discriminant analysis Southern Thailand
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Analysis of Morphometric Parameters and Radioactive Characteristics Using Remote Sensing Data and GIS Techniques in the Wadi Wizr Basin Area, Central Eastern Desert, Egypt
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作者 Sameh Anwar Ibrahim Hammouda Soliman Abu Elatta A. Mahmoud 《Journal of Geoscience and Environment Protection》 2023年第6期197-219,共23页
The purpose of this study is to demonstrate how modern technologies such as geographic information systems (GIS) and digital elevation models can help in the creation of a geographic database for the Wadi Wizr basin i... The purpose of this study is to demonstrate how modern technologies such as geographic information systems (GIS) and digital elevation models can help in the creation of a geographic database for the Wadi Wizr basin in Egypt’s Central Eastern Desert, in addition to examining and analysing the radioactive properties of various rocks. This was accomplished with the help of a digital elevation model (DEM) with a 30 metre accuracy and GIS software in 10.8 Arc Map. The RS-230 was also used to measure uranium and thorium concentrations. GIS softwares and digital elevation models have been shown to be more effective than the traditional method. This was demonstrated by the flexible and quick working method, the accuracy of the parameters used, and the results of the morphometric analysis of the basin river network. In addition to, the main drainage pattern from subtype to tree type, where the branching ratio was (1.59). This basin could also cause flooding. Similar studies, according to the results of this study, should make greater use of geographic information system technology and modern data sources. Wadi Wizr also has a radioactive anomaly, with uranium equivalent concentrations reaching 70 ppm in some fault parts. 展开更多
关键词 Wadi Wizr Basin morphometric analysis Drainage Pattern Radioactive Characteristics Remote Sensing Geographic Information System
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The Biodiversity of Shrimp Genus Artemia from Russian Lakes:Morphometric,Cytogenetics and DNA-analysis 被引量:1
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作者 Elena BOYKO Lyudmila LITVINENKO Aleksandr LITVINENKO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期58-60,共3页
Shrimps of genus Artemia are the inhabitants of continental and marine waters with salinity of 70 to 350 g/l and above.Artemia is able to survive in the conditions in which other animals cannot exist.This is due to ad... Shrimps of genus Artemia are the inhabitants of continental and marine waters with salinity of 70 to 350 g/l and above.Artemia is able to survive in the conditions in which other animals cannot exist.This is due to adaptations:effective osmoregulation system,the ability to synthesize of respiratory pigment(hemoglobin)and diapauses cysts(Litvinenko at.al.,2009).Cysts of this 展开更多
关键词 ARTEMIA morphometric analysis cytogenetic analysis DNA analysis salinity.
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Morphometric analysis and fluorescent microsatellite markers to evaluate the genetic diversity of five populations of Penaeus japonicus in China 被引量:1
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作者 Jinghao Du Chunxiu Hou +3 位作者 Xiuli Chen Jie Xiao Yasmeen Gul Huanling Wang 《Aquaculture and Fisheries》 2022年第3期321-327,共7页
To understand the current status of germplasm resources of Penaeus japonicus,in this study,genetic diversity was analyzed based on morphometric analysis and fluorescent microsatellite markers.For morphometric analysis... To understand the current status of germplasm resources of Penaeus japonicus,in this study,genetic diversity was analyzed based on morphometric analysis and fluorescent microsatellite markers.For morphometric analysis,the cumulative ratios of the PC1 and PC2(85.90%)were greater than 75%,which can explain the morphological variation among populations.For microsatellite analysis,the allele number in 10 microsatellite loci ranged from 27 to 53,and the effective allele number ranged from 21 to 42.The observed heterozygosity ranged from 0.463 to 0.983,whereas expected heterozygosity ranged from 0.932 to 0.966,and the average polymorphism information content was 0.947,which indicated a high level of genetic diversity.The unbiased genetic distance among populations ranged from 0.230 to 0.431,and the genetic similarity coefficient ranged from 0.654 to 0.782.Analysis of molecular variance(AMOVA)showed that the genetic variation within individuals was the main source of variation,accounting for 88.55%,and only 1.49%of the genetic variation came from among populations. 展开更多
关键词 Penaeus japonicus morphometric analysis Microsatellite markers Genetic diversity Genetic structure
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MORPHOMETRIC ANALYSIS OF SPINOUS CELL IN ORAL SUBMUCOUS FIBROSIS COMPARISON WITH NORMAL MUCOSA, LEUKOPLAKIA AND SQUAMOUS CELL CARCINOMA
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作者 高山 刘蜀凡 +1 位作者 沈子华 彭隆祥 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第5期33-36,共4页
The morphometric analysis of the spinous cell in 16 specimens of oral submucous fibrosis (OSF) was made by using interactive image analysis system (IBAS-II). 19 parameters of the size and shape were chosen, and compar... The morphometric analysis of the spinous cell in 16 specimens of oral submucous fibrosis (OSF) was made by using interactive image analysis system (IBAS-II). 19 parameters of the size and shape were chosen, and compared with normal mucosa, leukoplakia, dysplasia and carcinoma. The results indicated that the cell dimensions (area, perimeter, all kinds of diameter) and nuclear cytoplasmic ratio in OSF were between normal mucosa and dysplasia as well as carcinoma. The former showed a progressive decrease (P<0.01), and the latter showed a progressive increase (P<0.01). The dimensions of the nuclei did not show considerable differences among the groups (P>0.05). A series of discriminant functions had been developed with stepwise discriminant analysis, the agreement ratio for OSF was 93.75%. The decrease of cell area and the increase of nuclear cytoplasmic ratio could reflect a malignant progress. The cell morphometric model could discriminate OSF well from other groups, suggesting that the change of the epith 展开更多
关键词 LEUKOPLAKIA AND SQUAMOUS CELL CARCINOMA SCC morphometric analysis OF SPINOUS CELL IN ORAL SUBMUCOUS FIBROSIS COMPARISON WITH NORMAL MUCOSA OS NS
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Morphometric and Change Detection Analysis for Prioritization of Sub Basin Conservation, Case Study of Taita Hills
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作者 Mark Boitt Nyamwamu Bebeto 《International Journal of Geosciences》 2020年第10期591-612,共22页
The study is aimed at analyzing the risk of Taita Hills region of harmful runoff and soil erosion by employing morphometric analysis and change detection in a GIS environment to prioritize the Taita Hills in Taita Tav... The study is aimed at analyzing the risk of Taita Hills region of harmful runoff and soil erosion by employing morphometric analysis and change detection in a GIS environment to prioritize the Taita Hills in Taita Taveta County. The objective of the study was to characterize and give hierarchy in which the region should be conserved. The methodology adopted hydrological modeling, morphometric computation, Weighted Sum Analysis (WSA) and change detection. Hydrological modeling was vital in delineating the sub-watersheds and stream network. Morphometric computation and WSA was applicable in coming up with parameters and weighting the parameters for each sub-watershed’s prioritization. Change detection is related to how human activity is important for conservation as the effect of land forms and dimensions are compounded. Twenty-one fourth order streamed sub-watersheds were generated and prioritized using morphometry and change detection. Every sub-watershed is given a hierarchy based on the calculated compound parameter from the WSA equation developed and shows the risk of runoff and soil erosion. The morphometric prioritization shows 47% of the watersheds are in the high and very highly susceptible areas and there are two sub-watersheds with the highest land cover change. As well six sub-watersheds are risky with both land cover change and morphometry. 展开更多
关键词 Watershed Prioritization morphometric analysis GIS Change Detection
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The Nuclear Morphometric Analysis and its Clinical Value in Esophageal Cancer
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《Chinese Medical Journal》 SCIE CAS CSCD 1994年第9期44-44,共1页
The nuclear area (A)and nuclear roundness factor (NRF) of epithelial cells of 42 esophageal cancers and 10 normal esophagus’s were measured by morphometry and the results were compared with the extent of the tumor
关键词 The Nuclear morphometric analysis and its Clinical Value in Esophageal Cancer
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Watershed prioritization for conservation planning using RUSLE and morphometric methods,Northwestern Ethiopia
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作者 Agumassie Genet GELA Daniel Ayalew MENGISTU Daniel Asfaw BEKELE 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2242-2262,共21页
Soil erosion and the subsequent sedimentation are serious environmental problems.Improper land management coupled with intense rainfall has complicated the problem in the Ethiopian highlands.Consequently,soil loss cos... Soil erosion and the subsequent sedimentation are serious environmental problems.Improper land management coupled with intense rainfall has complicated the problem in the Ethiopian highlands.Consequently,soil loss costs a profound amount of the national GDP and deters land productivity.Quantifying soil loss and prioritizing areas for conservation is imperative for proper planning and resource management.Therefore,this study aimed at estimating the mean annual soil loss rate of Gilgel Abay watershed which has critical implications on Lake Tana and Abbay River(Upper Blue Nile River),using RUSLE and morphometric analysis methods.Datasets including rainfall,soil,Digital Elevation Model and land use/land cover were used to generate important parameters required for the soil loss estimation.Data collected through field observation,consultation with experts and document analysis were used for validation purposes.The results of the study reveal that the watershed experienced an average soil loss rate of 39.8 t ha^(-1)yr^(-1).Subsequently,nearly 25%(37,038 ha)of the watershed is threatened by moderate to very severe soil loss.Among the four sub watersheds,sub watershed 3(S3)and sub watershed 4(S4),which consist of about 65%(105,000 ha)of the total area of the study watershed,experienced an annual soil loss rate of over 30 t ha^(-1)yr^(-1).The amount of soil loss that the study watershed has experienced is above the soil loss tolerance level of Ethiopia(2-18 t ha^(-1)yr^(-1))and the tropical region(10 t ha^(-1)yr^(-1)).Similarly,the results of morphometric analysis showed that the studied watershed has S-shaped hypsometric curve,an indication for maturity stage of landscape development.The studied watershed is also characterized by a non-circular shaped drainage with rugged and dissected topography that contributes to high flash flood,peak discharge and incidence of soil loss.The result of both models signified that S3 and S4 are highly susceptible to soil erosion.Therefore,these two sub watersheds need priority for soil and water conservation(SWC)measures.Furthermore,the study demonstrated the importance of the integration of different models in the identification of soil erosion prone areas and prioritization for the proper implementation of SWC measures. 展开更多
关键词 Soil loss RUSLE model morphometric analysis Gilgel Abay watershed
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Phylogenetic and morphometric relationships between two species of genus Auxis from the South China Sea and Java Sea
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作者 HABIB Ahasan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第10期76-82,共7页
This study was aimed at examining the phylogenetic and morphometric relationship of frigate tuna(Auxis thazard) and bullet tuna(Auxis rochei) using mt DNA D-loop(control) region sequences and truss measurements,... This study was aimed at examining the phylogenetic and morphometric relationship of frigate tuna(Auxis thazard) and bullet tuna(Auxis rochei) using mt DNA D-loop(control) region sequences and truss measurements,respectively. Maximum-likelihood(ML) tree and median-joining network showed that haplotypes from Auxis populations grouped separately. Discriminant function analyses and non-metric multidimensional scaling of morphometric data showed that bullet and frigate tuna were differed mainly with respect to truss measurements on the anterior region, suggesting adaptation to different diets available in different environments. Historic demographic analyses of sequence data showed that both bullet and frigate tuna had not undergone a significant sudden population expansion recently. Non-significant value of Tajimas' s D and Fu's F_S were indicated an effective large and stable population size for longer period of both species in South China Sea and Java Sea species. This study gives first report on the complementary relationship between morphometric and genetic analysis in stock discrimination of genus Auxis. 展开更多
关键词 phylogenetic relationship mtDNA D-loop morphometric analysis Auxis thazard Auxis rochei
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Morphometric Characterization of a Watershed through SRTM Data and Geoprocessing Technique
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作者 Elias Rodrigues da Cunha Vitor Matheus Bacani 《Journal of Geographic Information System》 2016年第2期238-247,共10页
The aim of this study is to characterize the morphometry of a watershed using radar data Shuttle Radar Topographic Mission (SRTM) and GIS techniques. The study is conducted in the watershed of the Indaiá stream, ... The aim of this study is to characterize the morphometry of a watershed using radar data Shuttle Radar Topographic Mission (SRTM) and GIS techniques. The study is conducted in the watershed of the Indaiá stream, which is located in the southwestern region of the municipality of Aquidauana, MS, Brazil and has an area of 94.6764 km2</sup>. A tributary of the Taboco River consequently enters the Pantanal lowlands. Classical morphometric parameters were calculated and specialized through spatial analysis in geographic information systems. The main results of the morphometric characterization were the variables of form factor, drainage density, coefficient of compactness, and maintenance coefficient, as well as the relief parameters found, including the hypsometry, slope, aspect and relief dissection (horizontal and vertical amplitude). The integrated analysis of the variables (morphometric and relief) concludes that the watershed has low susceptibility to flooding but that the morphology of the relief and lithological structure favors the development of erosion processes in the watershed. 展开更多
关键词 SRTM DEM morphometric analysis GIS Remote Sensing PANTANAL
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Morphometric Behavior of Shahzad Watershed, Lalitpur District, Uttar Pradesh, India: A Geospatial Approach
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作者 Tanzeel Khatoon Akram Javed 《Journal of Geographic Information System》 2022年第3期193-220,共28页
Morphometric parameters are an important aspect for understanding the hydrological and morphological behaviour of the watershed. The present study is carried out in the region of the Bundelkhand region (India) which i... Morphometric parameters are an important aspect for understanding the hydrological and morphological behaviour of the watershed. The present study is carried out in the region of the Bundelkhand region (India) which is socio-economically backward and has a history of frequent drought hence studying the watershed characteristics with reference to morphometric analysis becomes important. The remote sensing and GIS technique has been utilized to mathematically quantify the parameters of the Shahzad watershed. The watershed is mainly fed by the Shahzad River (a tributary of Jamini River) flowing from south to north direction contributing the area of 1100 km<sup>2</sup>. The various morphometric aspect viz., linear, aerial, relief and morpho-tectonic parameters indicate that the watershed is elongated in shape and is slightly uplifted from the right side in the southern part. Moreover, the watershed experiences low dissection and low run-off discharge there by indicating less erosion in the area. The other factors like drainage density, drainage frequency, infiltration number and length of over land flow indicate that the watershed has high permeability and infiltration capacity. Through this study, it can be concluded that remote sensing and GIS can be fruitfully utilized in analysing the morphometric behaviour of the region. This helps the researcher, planner and stakeholders to establish the relationship between watershed characteristics, thereby resulting in watershed management and sustainable resource management. 展开更多
关键词 Shahzad Watershed morphometric analysis Watershed Characteristics Remote Sensing GIS
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GIS&Remote Sensing Based Morphometric Parameters and Topographic Changes of the Lower Orashi River in Niger Delta Desmond
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作者 Desmond Eteh Edirin Akpofure Solomon Otobo 《Journal of Atmospheric Science Research》 2022年第1期1-10,共10页
In watershed hydrology,the morphometric features of a river basin are vital to examine the lower Orashi River basin morphological and hydrological aspects,as well as its flood potential,based on their morphometric cha... In watershed hydrology,the morphometric features of a river basin are vital to examine the lower Orashi River basin morphological and hydrological aspects,as well as its flood potential,based on their morphometric characteristics using remotely sensed SRTM data that was analyzed with ArcGIS software.The areal,linear,and relief aspects of the Orashi River basin were examined as morphometric parameters.The lower Orashi river basin,according to the findings,has a total size of 625.61 km2 and a perimeter of 307.98 km,with a 5th order river network based on Strahler categorization and a dendritic drainage pattern.Because of low drainage density,the drainage texture is very fine,the relief is low,and the slope is very low.Bifurcation ratio,circularity ratio,drainage density aspect ratio,form factor,and stream frequency values indicate that the basin is less elongated and would produce surface runoff for a longer period,while topographic changes show that the river is decreasing with depth in the land area at about the same elevation as a result of sand deposited due to lack of maintenance by dredging,which implies that the basin is morphometrically elevated and sensitive to erosion and flooding.To understand geo-hydrological features and to plan and manage watersheds,morphometric analysis based on geographic information systems and remote sensing techniques is beneficial. 展开更多
关键词 morphometric analysis Topographic changes HYDROLOGY FLOOD GIS
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Current status and potential of morphometric sperm analysis 被引量:2
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作者 Alejandro Maroto-Morales Olga Garcia-Alvarez +4 位作者 Manuel Ramon Felipe Martinez-Pastor M Rocio Fernandez-Santos A Josefa Soler Jose Julian Garde 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第6期863-870,共8页
The spermatozoon is the most diverse cell type known and this diversity is considered to reflect differences in sperm function. How the diversity in sperm morphology arose during speciation and what role the different... The spermatozoon is the most diverse cell type known and this diversity is considered to reflect differences in sperm function. How the diversity in sperm morphology arose during speciation and what role the different specializations play in sperm function, however, remain incompletely characterized. This work reviews the hypotheses proposed to explain sperm morphological evolution, with a focus on some aspects of sperm morphometric evaluation; the ability of morphometrics to predict sperm cryoresistance and male fertility is also discussed. For this, the evaluation of patterns of change of sperm head morphometry throughout a process, instead of the study of the morphometric characteristics of the sperm head at different stages, allows a better identification of the males with different sperm cryoconservation ability. These new approaches, together with more studies employing a greater number of individuals, are needed to obtain novel results concerning the role of sperm morphometry on sperm function. Future studies should aim at understanding the causes of sperm design diversity and the mechanisms that generate them, giving increased attention to other sperm structures besides the sperm head. The implementation of scientific and technological advances could benefit the simultaneous examination of sperm phenotype and sperm function, demonstrating that sperm morphometry could be a useful tool for sperm assessment. 展开更多
关键词 computer-assisted sperm morphometric analysis MAMMALS sperm function sperm morphometry
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Differential development and electrophysiological activity in cultured cortical neurons from the mouse and cynomolgus monkey
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作者 Xue-Yan Zhang Jun Li +7 位作者 Cai-Juan Li Ying-Qi Lin Chun-Hui Huang Xiao Zheng Xi-Chen Song Zhu-Chi Tu Xiao-Jiang Li Sen Yan 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第12期2446-2452,共7页
In vitro cultures of primary cortical neurons are widely used to investigate neuronal function.However,it has yet to be fully investigated whether there are significant differences in development and function between ... In vitro cultures of primary cortical neurons are widely used to investigate neuronal function.However,it has yet to be fully investigated whether there are significant differences in development and function between cultured rodent and primate cortical neurons,and whether these differences influence the utilization of cultured cortical neurons to model pathological conditions.Using in vitro culture techniques combined with immunofluorescence and electrophysiological methods,our study found that the development and maturation of primary cerebral cortical neurons from cynomolgus monkeys were slower than those from mice.We used a microelectrode array technique to compare the electrophysiological differences in cortical neurons,and found that primary cortical neurons from the mouse brain began to show electrical activity earlier than those from the cynomolgus monkey.Although cultured monkey cortical neurons developed slowly in vitro,they exhibited typical pathological features-revealed by immunofluorescent staining-when infected with adeno-associated viral vectors expressing mutant huntingtin(HTT),the Huntington’s disease protein.A quantitative analysis of the cultured monkey cortical neurons also confirmed that mutant HTT significantly reduced the length of neurites.Therefore,compared with the primary cortical neurons of mice,cultured monkey cortical neurons have longer developmental and survival times and greater sustained physiological activity,such as electrophysiological activity.Our findings also suggest that primary cynomolgus monkey neurons cultured in vitro can simulate a cell model of human neurodegenerative disease,and may be useful for investigating time-dependent neuronal death as well as treatment via neuronal regeneration.All mouse experiments and protocols were approved by the Animal Care and Use Committee of Jinan University of China(IACUC Approval No.20200512-04)on May 12,2020.All monkey experiments were approved by the IACUC protocol(IACUC Approval No.LDACU 20190820-01)on August 23,2019 for animal management and use. 展开更多
关键词 Axion-MEA electrical activities human disease model Huntington’s disease HTT monkey neuron morphometric analysis mouse neuron neurodegenerative diseases primary culture
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Morphodynamic development of the Terkhiin Tsagaan Lake Depression,Central Mongolia:Implications for the relationships of Faulting,Volcanic Activity,and Lake Depression Formation
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作者 Altanbold ENKHBOLD Ulambadrakh KHUKHUUDEI +4 位作者 Timothy KUSKY CHUN Xi Gansukh YADAMSUREN Byambabayar GANBOLD Tuvshin GERELMAA 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2451-2468,共18页
Data on the origin and morphology of lake depressions caused by volcanism are scarce in Mongolia.Previous studies focused on climate change patterns based on Terkhiin Tsagaan Lake sediment.We present a result of exist... Data on the origin and morphology of lake depressions caused by volcanism are scarce in Mongolia.Previous studies focused on climate change patterns based on Terkhiin Tsagaan Lake sediment.We present a result of existing reconstructions of lake depression development and changes in the hydrology system during the Khorgo volcanic activation and the Holocene environmental change.A depression of the Terkhiin Tsagaan Lake is formed by a lava flow barrier from the Khorgo volcano.However,the Khorgo volcanic eruption and the lake depression that could shape a large lake have arisen instead from a fault.The morphometric analysis and field measurements indicate that the derivation of the Terkhiin Tsagaan Lake depression and Khorgo volcano may have evolved from movement on a sinistral strike-slip fault,which is about 70 km long.The southern mountains and rivers were displaced from northwest to southeast along the Terkh Fault.The offset along Terkh Fault is 4.02-5.28 km in the depression of the Terkhiin Tsagaan Lake.After movement,a wide valley of the Terkh River developed in the present landscape.The active Khorgo Volcano formed along the Khorgo Fault.The Terkhiin Tsagaan Lake is formed by blocked water from the PaleoTerkh River after lava damming from the Khorgo Volcano.The initial paleo-lake area was about 195.7km^(2),which was three times larger than the modern lake.The current water volume of the Terkhiin Tsagaan Lake is 0.351 km^(3) while the volume of the paleo-lake was 2.248 km^(3).Based on this volume indicator the paleo-lake was 6.4 times larger than the current lake.Overflowing water from the lake depression formed the Suman River by a drying canyon through the lava plateau,but the canyon is along the Terkh Fault.Changes in the water volume of Terkhiin Tsagaan Lake and erosion of Suman River canyon are inversely related to each other.We present the morphometric relationships between the lava plateau of Khorgo Volcano and development of Terkhiin Tsagaan Lake depression. 展开更多
关键词 Khangay Mountain Khorgo Volcano Lava plateau Sinistral strike-slip fault Terkhiin Tsagaan Lake morphometric analysis
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Taxonomic Studies on Some Members of the Genus <i>Abutilon</i>Mill. (Malvaceae)
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作者 Dhafer A. Alzahrani Enas J. Albokhari Abrar Khoj 《American Journal of Plant Sciences》 2021年第2期199-220,共22页
The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using diffe... The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using different taxonomic investigation tools. The investigation was carried out using morphological and numerical studies. Fresh materials of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species were collected from different localities in Saudi Arabia during 2018 and 2019. Numerical analysis was based on the Principle Coordinates, the Principle Component and the Unweighted Pair Group Method with Arithmetic Algorithm Clustering. The results indicated that there were significant differences based on the morphological characters especially in the leaves, fruits and flowers features. Morphometric studies revealed that the six species of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> clearly separated in all different analysis. 展开更多
关键词 Taxonomy MALVACEAE Abutilon Morphological Characters morphometric analysis UPGMA PCoA PCA
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Fluvial Geomorphology and Basin Development of Karra Khola Basin, Hetauda, Central Nepal
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作者 Manju Subedi Naresh Kazi Tamrakar 《Journal of Geological Research》 2020年第4期1-13,共13页
Geomorphological study of a basin is important for understanding theoverall basin characteristics which are helpful for the management of waterresources, construction along the river bank and natural hazard mitigation... Geomorphological study of a basin is important for understanding theoverall basin characteristics which are helpful for the management of waterresources, construction along the river bank and natural hazard mitigationwithin the area. The study was carried out in the Karra Khola Basin, oneof the prominent basins in the Eastern extreme of the Hetauda Dun Valley,Central Nepal, to investigate geomorphic characteristics of the mainstream of the basin, categorize them into various stream types and studybasin development through drainage basin’s morphometric parameters.Geographical Information System (GIS) and Remote sensing techniquesusing satellite images were used as a tool to make the morphometricanalysis of the basin along with its major 13 sub-basin and delineate streamclassification following the Rosgen’s Level I hierarchical inventory. Themain stream of the Karra Khola is characterized as A-, B- and C-typeand the tributaries segments as B- and F-type. The basin is structurallyunaffected and has the permeable surface area and elongated shape. Thehypsometric analysis indicates that the basin is mostly at the old stage ofgeomorphic development while four out of 13 sub-basin being at maturestage. The Karra Khola sub-basin have higher risk to flash flooding(Lg=0.1-0.16km). Drainage density value reveals that the basin is highlysusceptible to flooding, gully erosion, etc. Similarly, dissection index valueimplies that the north eastern region of the basin is highly vulnerable toerosion as it at the younger stage of geomorphic development. Since thestudy area is highly sensitive to future natural hazards, further study andappropriate measures should be followed for safeguarding against thefuture risk along the Karra Khola basin and its tributaries. 展开更多
关键词 morphometric analysis Stream classification Hypsometric analysis Geomorphic development Drainage density Dissection index Natural hazards EROSION
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Implementation of Remote Sensing and GIS Techniques to Study the Flash Flood Risk at NEOM Mega-City, Saudi Arabia
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作者 Ahmed A. Abdulalim Tarek A. El Damaty 《Advances in Remote Sensing》 2022年第4期121-157,共37页
Southern Red Sea flooding is common. Assessing flood-prone development risks helps decrease life and property threats. It tries to improve flood awareness and advocate property owner steps to lessen risk. DEMs and top... Southern Red Sea flooding is common. Assessing flood-prone development risks helps decrease life and property threats. It tries to improve flood awareness and advocate property owner steps to lessen risk. DEMs and topography data were analyzed by RS and GIS. Fifth-through seventh-order rivers were studied. Morphometric analysis assessed the area’s flash flood danger. NEOM has 14 catchments. We determined each catchment’s area, perimeter, maximum length, total stream length, minimum and maximum elevations. It also uses remote sensing. It classifies Landsat 8 photos for land use and cover maps. Image categorization involves high-quality Landsat satellite images and secondary data, plus user experience and knowledge. This study used the wetness index, elevation, slope, stream power index, topographic roughness index, normalized difference vegetation index, sediment transport index, stream order, flow accumulation, and geological formation. Analytic hierarchy considered all earlier criteria (AHP). The geometric consistency index GCI (0.15) and the consistency ratio CR (4.3%) are calculated. The study showed five degrees of flooding risk for Wadi Zawhi and four for Wadi Surr, from very high to very low. 9.16% of Wadi Surr is vulnerable to very high flooding, 50% to high flooding, 40% to low flooding, and 0.3% to very low flooding. Wadi Zawhi’s flood risk is 0.23% high, moderate, low, or extremely low. They’re in Wadi Surr and Wadi Zawhi. Flood mapping helps prepare for emergencies. Flood-prone areas should prioritize resilience. 展开更多
关键词 Geographic Information System (GIS) Remote Sensing Flash Floods Hazard Assessment Analytic Hierarchy Process (AHP) morphometric analysis Hydrology analysis
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Evaluation of periglacial landforms and formation of soil properties on the Mount Honaz,SW Türkiye
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作者 SERİN Soner UNCU Levent +1 位作者 DEDE Volkan TÜRKEŞMurat 《Journal of Mountain Science》 SCIE 2024年第9期3047-3067,共21页
The main aim of this study is to explain periglacial processes on the summits of Mount Honaz(2571 m a.s.l.),define periglacial landforms,and determine the relationships between morphometric features and topographic fa... The main aim of this study is to explain periglacial processes on the summits of Mount Honaz(2571 m a.s.l.),define periglacial landforms,and determine the relationships between morphometric features and topographic factors.Mud circles,stony earth circles,non sorted steps,and non sorted stripes were identified on the summits of Mount Honaz.Pearson's correlation coefficient(r)and linear regression analyses were performed by taking metric measurements from 125 periglacial landforms to describe their morphometric features(length,width,height)of periglacial landforms and explain the relationships between them and topographic factors(elevation,slope).To explain the relationships between periglacial landforms and soil properties,soil samples from 11 periglacial landforms were taken and analysed.Periglacial landforms,which continue to develop on the summits of Mount Honaz today,have been evaluated with present climate data.Analysis of soil samples indicates a notable impact of parent material on the genesis of periglacial landforms.The high ratio of organic matter in mud circle and non sorted step landforms and the high lime ratio in stony earth circle landforms prove a strong relationship between the formation mechanisms of landforms and the soil properties.Furthermore,it is consistent with the findings obtained from the analysis that severe periglacial processes and washing and scavenging events are experienced more on the northern slopes. 展开更多
关键词 Periglacial processes and geomorphology Soil analysis morphometric analysis Mount Honaz Türkiye
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