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Body Size but Not Food Size Determined Head Sexual Dimorphism in Rana kukunoris from the Tibetan Plateau 被引量:1
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作者 Hongzhou CHEN Haifen QIN +6 位作者 Zhenkun ZHAO Jiahong LIAO Yanfang WU Xueyan LIU Lichun JIANG Buddhi DAYANANDA Wei CHEN 《Asian Herpetological Research》 SCIE CSCD 2023年第2期175-181,共7页
Sexual dimorphism between males and females is a common pattern observed in the natural world and has become one of the main focuses of evolutionary biology.Amphibian head size and shape are important factors that may... Sexual dimorphism between males and females is a common pattern observed in the natural world and has become one of the main focuses of evolutionary biology.Amphibian head size and shape are important factors that may influence food acquisition,but knowledge about the sexual differences between amphibian head size and shape is relatively scant.Here,intersexual differences in the head size and shape of Rana kukunoris,which is a high-elevation frog from the Qinghai-Tibet Plateau,were investigated.Significant differences were found in the head shape but not the head size between sexes.A significant correlation was also observed between prey size and head size.However,these correlations disappeared when individual body size was controlled,suggesting that body size but not food size was the main factor resulting in intersexual differences in head size/shape.The results suggested that food competition between sexes did not result in sexual dimorphism of head shape among these frogs. 展开更多
关键词 AMPHIBIANS head shape MORPHOMETRICS RANA Rana kukunoris sexual dimorphism
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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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Survival of rat sciatic nerve segments preserved in storage solutions ex vivo assessed by novel electrophysiological and morphological criteria
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作者 Liwen Zhou Monzer Alatrach +2 位作者 Ted Zhao Paul Oliphint George D.Bittner 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期2082-2088,共7页
Most organ or tissue allografts with viable cells are sto red in solutions ex vivo for hours to seve ral days.Most allografts then require rapid host revascula rization upon transplantation to maintain donor-cell func... Most organ or tissue allografts with viable cells are sto red in solutions ex vivo for hours to seve ral days.Most allografts then require rapid host revascula rization upon transplantation to maintain donor-cell functions(e.g.,cardiac muscle contra ctions,hepatic secretions).In contrast,peripheral nerve allografts stored ex vivo do not require revascularization to act as scaffolds to guide outgrowth by host axons at 1-2 mm/d,likely aided by viable donor Schwann cells.Using current storage solutions and protocols,axons in all these donor orga n/tissue/nerve transplants are expected to rapidly become non-viable due to Wallerian degeneration within days.Therefore,ex vivo storage solutions have not been assessed for preserving normal axonal functions,i.e.,conducting action potentials or maintaining myelin sheaths.We hypothesized that most or all organ storage solutions would maintain axonal viability.We examined several common organ/tissue storage solutions(University of Wisconsin Cold Storage Solution,Normosol-R,Normal Saline,and La ctated Ringe rs) for axonal viability in rat sciatic nerves ex vivo as assessed by maintaining:(1) conduction of artificially-induced compound action potentials;and(2) axonal and myelin morphology in a novel assay method.The ten diffe rent storage solution conditions for peripheral nerves with viable axons(PNVAs) diffe red in their solution composition,osmolarity(250-318 mOsm),temperature(4℃ vs.25℃),and presence of calcium.Compound action potentials and axonal morphology in PNVAs were best maintained for up to 9 days ex vivo in calcium-free hypotonic diluted(250 mOsm) Normosol-R(dNR) at 4℃.Surprisingly,compound action potentials were maintained for only 1-2 days in UW and NS at 4℃,a much shorter duration than PNVAs maintained in 4℃ dNR(9 days) or even in 25℃ dNR(5 days).Viable axons in peripheral nerve allografts are critical for successful polyethylene glycol(PEG)-fusion of viable proximal and distal ends of host axons with viable donor axons to repair segmental-loss peripheral nerve injuries.PEG-fusion repair using PNVAs prevents Wallerian degeneration of many axons within and distal to the graft and results in excellent recovery of sensory/motor functions and voluntary behaviors within weeks.Such PEG-fused PNVAs,unlike all other types of conventional donor transplants,are immune-tolerated without tissue matching or immune suppression.Preserving axonal viability in sto red PNVAs would enable the establishment of PNVA tissue banks to address the current shortage of transplantable nerve grafts and the use of stored PEG-fused PNVAs to repair segmentalloss peripheral nerve injuries.Furthermore,PNVA storage solutions may enable the optimization of ex vivo storage solutions to maintain axons in other types of organ/tissue transplants. 展开更多
关键词 axonal morphometrics axonal viability calcium OSMOLARITY peripheral nerve grafts peripheral nerve injury temperature tissue storage solutions TONICITY Wallerian degeneration
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Evaluation of Morphometric Parameters Studies in Middle-West Part of Kushtia District, Bangladesh, Using Remote Sensing and GIS Techniques
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作者 Khan M. Nasir Uddin Md. Nozibul Haque 《Journal of Geoscience and Environment Protection》 2023年第1期211-231,共21页
This study finds 1D, 2D and 3D morphometric parameters of the middle-west part of Kushtia district, Bangladesh to implement groundwater potential. For this purpose, the SRTM (DEM) data were used to compute different p... This study finds 1D, 2D and 3D morphometric parameters of the middle-west part of Kushtia district, Bangladesh to implement groundwater potential. For this purpose, the SRTM (DEM) data were used to compute different parameters in GIS environment. The values of 1D parameters like stream order, stream length and mean bifurcation ratio was calculated as 6, 1774.72 km and 2.08 respectively. The computed values of drainage density (0.01 - 23.06 km/km<sup>2</sup>), stream frequency (1 - 5.64 per km<sup>2</sup>), drainage texture (0.25 - 0.70 km/km<sup>4</sup>), length of overland flow (0.02 - 45.05 km<sup>2</sup>/km), constant of channel maintenance (0.04  - 90.04 km<sup>2</sup>/km), circularity ratio (0.39 - 0.84), form factor (0.35), elongation ratio (0.62), relief ratio (0.00 - 1.81) and ruggedness number (0.04 - 214.72) disclose the morphometrical conditions of the study area. The results revealed from this study on drainage morphometry can be a great assistance for understanding the hydro-geomorphological character of the area. 展开更多
关键词 GIS SRTM (DEM) Morphometric Parameters GROUNDWATER
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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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Chitosan tubes enriched with fresh skeletal muscle fibers for delayed repair of peripheral nerve defects 被引量:2
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作者 AlessANDro Crosio Benedetta Elena Fornasari +5 位作者 Giovanna Gambarotta Stefano Geuna Stefania Raimondo Bruno Battiston Pierluigi Tos Giulia Ronchi 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第6期1079-1084,共6页
Nerve regeneration after delayed nerve repair is often unsuccessful. Indeed, the expression of genes associated with regeneration, including neurotrophic and gliotrophic factors, is drastically reduced in the distal s... Nerve regeneration after delayed nerve repair is often unsuccessful. Indeed, the expression of genes associated with regeneration, including neurotrophic and gliotrophic factors, is drastically reduced in the distal stump of chronically transected nerves; moreover, Schwann cells undergo atrophy, losing their ability to sustain regeneration. In the present study, to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth, we combined the use of an effective conduit(a chitosan tube) with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers). This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction. Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft, considered the "gold standard" technique for nerve reconstruction. Since hollow tubes not always lead to good results after long defects(> 20 mm), we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps, as muscle fibers create a favorable three-dimensional environment and release trophic factors. All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number: 864/2016/PR) on September 14, 2016. 展开更多
关键词 tubulization Schwann cells SCAFFOLD tissue engineering NERVE reconstruction morphometrical analyses GRASPING test SECONDARY repair MEDIAN NERVE NERVE regeneration
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The levels of serum fibrosis marks and morphometric quantitative measurement of hepatic fibrosis 被引量:13
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作者 Shi-Bin Xie Ji-Lu Yao +2 位作者 Shu-Sen Zheng Chun-Lan Yao Rong-Qin Zheng From the Department of Infectious Diseases, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第2期202-206,共5页
Objective: To study the relationship between the ser- um levels of hyaluronic acid (HA), procollagen type Ⅲ (PCⅢ), collagen type Ⅳ (CIV) and the histologi- cal degree of hepatic fibrosis evaluated by image analysis... Objective: To study the relationship between the ser- um levels of hyaluronic acid (HA), procollagen type Ⅲ (PCⅢ), collagen type Ⅳ (CIV) and the histologi- cal degree of hepatic fibrosis evaluated by image analysis, and the clinical significance of serum HA, PC Ⅲ, C Ⅳ in the diagnosis of hepatic fibrosis in pa- tients with chronic viral hepatitis. Methods: The concentrations of serum HA, PC Ⅲ, C Ⅳ in 151 patients with chronic viral hepatitis were measured by radioimmunoassay. Liver biopsies were performed in all the patients. Histological sections of 4 μm thickness were stained with Masson's trichrome for fibrosis assessment. Morphometric quantitative measurements for hepatic fibrosis assessment in the 4 μm sections were performed using a fully automated image analysis system. Serum levels of HA, PC Ⅲ, and C Ⅳ were analyzed at different stages of liver pa- thology and compared with the morphometric quanti- tative measurements of hepatic fibrosis. Results: The serum levels of HA, PC Ⅲ, C Ⅳ all ele- vated gradually with the progression of the disease, and all reached the highest in patients with liver cir- rhosis. There was a significant difference in the levels of these 3 components between liver cirrhosis group and the other groups (P<0.05). They all increased steadily with the histological stages of hepatic fibrosis, and reached the highest levels in stage Ⅳ. The serum levels of HA, PC Ⅲ, C Ⅳ were all positive- ly correlated with the histological stages of liver sec- tions and the morphometric measurement (P< 0.001). The coefficients with stages were 0.694, 0.493, 0.552 (P<0.001), respectively and with sur- face density of total collagen on liver biopsy sections by image analysis were 0. 715, 0. 595, 0. 573 (P< 0.001), respectively. Conclusion: The serum levels of HA, PC Ⅲ, C Ⅳ were in consistent with the degree of hepatic fibrosis, and the determination of these marks is valuable for detecting hepatic fibrosis. 展开更多
关键词 hyaluronic acid procollagen type collagen type hepatic fibrosis morphometric measurement
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几何形态学对8种扇贝的形态分类的应用
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作者 舒予 史令 +4 位作者 郝振林 毛俊霞 王许波 田莹 常亚青 《海洋科学》 CAS CSCD 北大核心 2022年第6期61-69,共9页
几何形态学(morphometrics)是基于笛卡尔地标点的统计分析方法,主要运用广义普鲁克分析(GPA)、薄板样条分析(TPS)、主成分分析(PCA)、典型变量分析(CVA)等方法,定量的对形态变化进行识别,结果更为客观。本研究运用几何形态学方法对8种... 几何形态学(morphometrics)是基于笛卡尔地标点的统计分析方法,主要运用广义普鲁克分析(GPA)、薄板样条分析(TPS)、主成分分析(PCA)、典型变量分析(CVA)等方法,定量的对形态变化进行识别,结果更为客观。本研究运用几何形态学方法对8种常见扇贝(栉孔扇贝Azumapecten farreri、虾夷盘扇贝Mizuhopecten yessoensis、海湾扇贝Argopecten irradians、平濑掌扇贝Volachlamys hirasei、北海道扇贝Swiftopecten swiftii、荣套扇贝Gloripallium pallium、华贵类栉孔扇贝Mimachlamys nobilis、美丽环扇贝Annachlamys striatula)间形态关系进行研究,运用界标点和半界标点对扇贝的壳盘和壳耳进行数字化标点,利用PCA、CVA、TPS方法,获得8种扇贝的形态差异并进一步分析,建立系统发育树。PCA和CVA分析结果表明可以通过几何形态测量学分析方法将8种扇贝基于形态差异进行有效区分。此外,结合TPS的分析结果,发现壳耳和壳盘在扇贝中具有种间规律性差异。通过其形态分异进行表型聚类,从结果可知:美丽环扇贝、虾夷盘扇贝和海湾扇贝距离较近,壳型有共同的特征:扇贝壳盘较椭圆,壳耳相对较小;荣套扇贝和华贵类栉孔扇贝距离较近,壳型有共同的特征:扇贝壳盘更扁平,前耳相对较大;北海道扇贝、平濑掌扇贝和栉孔扇贝与其他种类没有交集。在聚类过程中,华贵类栉孔扇贝和荣套扇贝有交集,10个标本混淆,其他标本均成功聚类,正确率为95.5%。 展开更多
关键词 几何形态测量学(morphometrics) 扇贝科 形态分类 系统发育
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Cranial variation in allactagine jerboas(Allactaginae,Dipodidae, Rodentia): a geometric morphometric study 被引量:3
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作者 Bader H.Alhajeri 《Zoological Research》 SCIE CAS CSCD 2021年第2期182-194,共13页
Allactaginae is a subfamily of dipodids consisting of four-and five-toed jerboas(Allactaga, Allactodipus,Orientallactaga, Pygeretmus, Scarturus) found in open habitats of Asia and North Africa. Recent molecular phylog... Allactaginae is a subfamily of dipodids consisting of four-and five-toed jerboas(Allactaga, Allactodipus,Orientallactaga, Pygeretmus, Scarturus) found in open habitats of Asia and North Africa. Recent molecular phylogenies have upended our understanding of this group's systematics across taxonomic scales. Here, I used cranial geometric morphometrics to examine variation across 219 specimens of 14 allactagine species(Allactaga major, A. severtzovi, Orientallactaga balikunica, O.bullata, O. sibirica, Pygeretmus platyurus, P. pumilio,P. shitkovi, Scarturus aralychensis, S. euphraticus,S. hotsoni, S. indicus, S. tetradactylus, S. williamsi)in light of their revised taxonomy. Results showed no significant sexual size or shape dimorphism. Species significantly differed in cranial size and shape both overall and as species pairs. Species identity had a strong effect on both cranial size and shape. Only a small part of cranial shape variation was allometric,with no evidence of unique species allometries, and most specimens fit closely to the common allometric regression vector. Allactaga was the largest,followed by Orientallactaga, Scarturus, and finally Pygeretmus. Principal component 1(PC1) separated O. bullata+O. balikunica+S. hotsoni(with inflated bullae along with reduced zygomatic arches and rostra) from A. major+A. severtzovi+O. sibirica(with converse patterns), while PC2 differentiated Orientallactaga(with enlarged cranial bases and rostra along with reduced zygomatic arches and foramina magna) from Scarturus+Pygeretmus(with the opposite patterns). Clustering based on the unweighted pair group method with arithmetic mean(UPGMA) contained the four genera, but S. hotsoni clustered with O. bullata+O. balikunica and O.sibirica clustered with A. major+A. severtzovi, likely due to convergence and allometry, respectively. 展开更多
关键词 Allactaga Cranial morphometrics Five-toed jerboas Orientallactaga Pygeretmus Scarturus
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Prioritization of Semi-Arid Agricultural Watershed Using Morphometric and Principal Component Analysis, Remote Sensing, and GIS Techniques, the Zerqa River Watershed, Northern Jordan 被引量:7
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作者 Yahya Farhan Ali Anbar +1 位作者 Nisrin Al-Shaikh Rami Mousa 《Agricultural Sciences》 2017年第1期113-148,共36页
Remote sensing and GIS techniques were employed for prioritization of the Zerqa River watershed. Forty-three 4th order sub-watersheds were prioritized based on morphometric and Principal Component Analysis (PCA), in o... Remote sensing and GIS techniques were employed for prioritization of the Zerqa River watershed. Forty-three 4th order sub-watersheds were prioritized based on morphometric and Principal Component Analysis (PCA), in order to examine the effectiveness of morphometric parameters in watershed prioritization. A comparison has been carried out between the results achieved through applying the two methods of analysis (morphometric and PCA). Afterwards, suitable measures are proposed for soil and water conservation. Topo sheets and ASTER DEM have been employed to demarcate the 43 sub-watersheds, to extract the drainage networks, and to compile the required thematic maps such as slope categories and elevation. LANDSAT 8 image (April-2015) is employed to generate land use/cover maps using ENVI (v 5.1) software. The soil map of the watershed has been digitized using Arc GIS software. Prioritization of the 43 sub-watersheds was performed using ten linear and shape parameters, and three parameters which are highly correlated with components 1 and 2. Subsequently, different sub-watersheds were prioritized by ascribing ranks based on the calculated compound parameters (Cp) using the two approaches. Comparison of the results revealed that prioritization of watersheds based on morphometric analysis is more consistent and serves for better decision making in conservation planning as compared with the PCA approach. The recommended soil conservation measures are prescribed in accordance with the specified priority, in order to avoid undesirable effects on land and environment. Sub-watersheds classified under high priority class are subjected to high erosion risk, thus, creating an urgent need for applying soil and water conservation measures. It is expected that decision makers will pay sufficient attention to the present results/information, activate programs encouraging soil conservation, integrated watershed management, and will continue working on the afforestation of the government-owned sloping lands. Such a viable approach can be applied at different parts of the rainfed highland areas to minimize soil erosion loss, and to increase infiltration and soil moisture in the soil profile, thus, reducing the impact of recurrent droughts and the possibility of flooding hazards. 展开更多
关键词 PRIORITIZATION MORPHOMETRIC ANALYSIS Principal Component ANALYSIS Soil Conservation Land Use/Cover GIS
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Morphometric discrimination of wild from farmed Dybowski’s frog (Rana dybowskii) based on hindlimb length 被引量:3
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作者 XIA Rui HUANG Xiao-ming +3 位作者 YANG Shu-hui XU Yan-chun Ying Lu Thomas D. Dahmer 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期269-274,共6页
Commercial farming of anuran species that are declining in the wild raises a need to discriminate wild from farmed frogs.We hypothesized wild frogs might have extended hindlimbs due to greater frequency or intensity o... Commercial farming of anuran species that are declining in the wild raises a need to discriminate wild from farmed frogs.We hypothesized wild frogs might have extended hindlimbs due to greater frequency or intensity of jumping relative to farmed frogs,highlighting a morphometric approach to discrimination of wild from farmed frogs using hindlimb length.In the present study,Dybowski's frog(Rana dybowskii) was used to test this hypothesis.We measured body mass(Mb) and hindlimb length(Lh) of 2-year old farmed frogs and wild frogs aged 2 to 5 years.Dybowski's frog demonstrated significant dimorphism in Mb and Lh.Mb was significantly greater among farmed 2-year old frogs in both sexes(p=0.000),while only among females was Lh significantly greater for wild frogs(p=0.000).Lh/Mb was used as an index for origin discrimination to eliminate the influence of Mb due to variation of husbandry conditions among farms.Mean Lh/Mb for farmed frogs was significantly lower than for wild frogs(p=0.000) in the 2-year old age class.Discrimination correctly classified 84.4% of farmed and 96.3% of wild male frogs.Among females,92.9% of farmed frogs and 90.1% wild frogs were correctly classified.The overall correctness of classification was 92.1% and 90.8% for males and females,respectively.However,Lh/Mb revealed variation with age,resulting in reduced discriminative power for frogs ≥3 years old.We introduced a coefficient Ce to adjust the Lh/Mb of frogs ≥3 years to the level equivalent to 2-year frogs.The adjustment achieved 89.5% for overall correctness of origin for wild males and 92.4% for wild females ≥3 years old.These results show that Lh/Mb is an effective index to discriminate wild from farmed Dybowski's frog.Since the physical demands of jumping are common among anurans,this index is also potentially applicable to other anuran species. 展开更多
关键词 Dybowski's frog morphometric discrimination WILD FARMED Rana dybowskii
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Three-dimensional Morphometric Analyses of Hominoid Lower Molars from Yuanmou in Yunnan Province,China 被引量:2
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作者 Alan Walker 《人类学学报》 CSCD 北大核心 2002年第S1期1-13,共13页
Analysis of 3D measurements of 13 landmarks on 72 Yuanmou Hominoid lower molars and some comparative samples, using Euclidean Distance Matrix Analysis (EDMA), show that the 3D morphometric features of Yuanmou Homi noi... Analysis of 3D measurements of 13 landmarks on 72 Yuanmou Hominoid lower molars and some comparative samples, using Euclidean Distance Matrix Analysis (EDMA), show that the 3D morphometric features of Yuanmou Homi noid lower molars largely resemble those of Lufengpithecus. Compared with extant great apes and humans, both Yuanmou Hominoid and Lufengpithecus differ markedly from humans, whereas they show much resemblance to apes. The two Chinese hominoids and extant great apes are different from humans in many of the same ways. Moreover, 3D morphometric features of Yuanmou Hominoid lower molars differ from those of each of the three extant great apes in similar ways. Of the three, the orangutan is the closest match to Yuanmou Hominoid in tooth morphology. However, the exact implications of these similarities and differences remain to be determined. 展开更多
关键词 Yuanmou Hominoid Lufengpithecus MORPHOMETRICS 3D analysis EDMA
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Intraspecific leaf morphological variation in Quercus dentata Thunb.:a comparison of traditional and geometric morphometric methods,a pilot study 被引量:1
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作者 Kaiyu Yang Jianghao Wu +4 位作者 Xinman Li Xinbo Pang Yangchen Yuan Guohui Qi Minsheng Yang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第6期1751-1764,共14页
To compare the application of traditional morphometric methods(TMMs)and geometric morphometric methods(GMMs)in the study of intraspecific leaf morphological characters of Quercus dentata,fifteen linear measurement ind... To compare the application of traditional morphometric methods(TMMs)and geometric morphometric methods(GMMs)in the study of intraspecific leaf morphological characters of Quercus dentata,fifteen linear measurement indices and thirteen landmarks of leaves were used to study leaf morphology of three provenances(H1,H2,and H3).In TMMs,principal component analysis(PCA)showed that leaf size–related indices played an important role in population classification.Partial least square(PLS)analysis showed that the main morphological characters affecting leaf size were the average depth of the lobes and the length–width ratios.However,the important indices to distinguish the provenances were circularity,leaf width,and length–width ratio.The results of discriminant analysis(DA)showed that 74.0%of H1,68.0%of H2,and 74.0%of H3 were correctly classified.Cluster analysis showed that the Mahalanobis distances between H1 and H2,H1 and H3,and H2 and H3 were 4.3761,11.4629,and 10.2067,respectively.In GMMs,PCA based on symmetrical components showed that the difference in leaf morphology was mainly due to the changing trend of the leaf apex and base,petiole length,and degree of leaf cracking.PLS analysis showed that there was a significant covariation between the leaf symmetrical components and size:as the leaf enlarged,the widest part gradually moved up,and the shape changed from nearly oval to lanceolate.DA results showed that 86.0%and 78.0%of H1 and H2,70.0%and 80.0%of H1 and H3,and 82.0%and 76.0%of H2 and H3 were correctly classified.Canonical variate analysis results showed that the Mahalanobis distances between H1 and H2,H1 and H3,and H2 and H3 were 1.7238,1.5380,and 1.6329,respectively.Both GMMs and TMMs showed significant differences in morphology among the three Q.dentata provenances,but GMMs had higher classification accuracy and could provide more information about leaf shape,whereas TMMs could provide more information about leaf size.Based on our results,GMMs are promising in the study of leaf morphological variation within Q.dentata provenances. 展开更多
关键词 Traditional morphometrics Geometric morphometrics Leaf morphology variation Quercus dentata INTRASPECIFIC
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Morphometric, Physicochemical, Thermal, and Rheological Properties of Rice (<i>Oryza sativa</i>L.) Cultivars <i>Indica ×Japonica</i> 被引量:2
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作者 Laura Elizabeth Morales-Martínez Luis Arturo Bello-Pérez +2 位作者 Mirna María Sánchez-Rivera Elsa Ventura-Zapata Antonio Ruperto Jiménez-Aparicio 《Food and Nutrition Sciences》 2014年第3期271-279,共9页
The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate... The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate new varieties from Indica and Japonica cultivars. Morphometric parameters of the grains were evaluated by image analysis. Flours were prepared from the whole rice grains and physicochemical, thermal and rheological properties, X-ray diffraction pattern and evaluation of color using the CIELAB system were assessed. The hybrids lines showed long (061, 611, 721), medium (719 and 720) and short (067) grains. The rice samples presented lipids (2.6% - 3.2%), protein (11% - 15%), total dietary fiber (8.4% - 10.2%), total starch (65% - 74%) and apparent amylose (5% - 32%) contents. Gelatinization temperature (Tp) was found in the range of 66.1℃ - 79.4℃ with enthalpy (ΔH) value between 3.4 - 8.1 J/g. The retrogradation parameters (temperature and ΔH) were lower than those for gelatinization in all samples. The rice samples presented A-type X-ray diffraction pattern. Rice pastes showed a non-Newtonian behavior and the brightness (L*) characterize the color of the samples. Hybrid rice grains presented morphometric properties more similar to Japonica than Indica variety. Rice hybrid had higher protein content than Indica variety. Apparent amylose, viscosity and gelatinization temperature varied significantly among hybrids and varieties. 展开更多
关键词 Brown RICE Hybrid Grains MORPHOMETRIC Parameters GELATINIZATION Temperature Flow Behavior PASTING Viscosity
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Quantitative Analysis of Flabellophyton from the Ediacaran Lantian Biota, South China: Application of Geometric Morphometrics in Precambrian Fossil Research 被引量:1
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作者 WAN Bin YUAN Xunlai +4 位作者 CHEN Zhe GUAN Chengguo PANG Ke TANG Qing RAO Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期905-915,共11页
As a more efficient quantitative method for morphological analysis, geometric morphometrics is applied to the flabellate fossils Flabellophyton including Flabellophyton lantianensis and Flabellophyton strigata from Ne... As a more efficient quantitative method for morphological analysis, geometric morphometrics is applied to the flabellate fossils Flabellophyton including Flabellophyton lantianensis and Flabellophyton strigata from Neoproterozoic Ediacaran Lantian biota, South China. Both traditional morphometric analysis (including diverging angle, length, and width distribution) and geometric morphometric analysis [including superposition of normalized area analysis, non-metric multidimensional scaling (n-MDS), Bray-Curtis similarity cluster analysis (CLUSTER) and analysis of similarities (ANOSIM)[ were performed. The results indicate there are great interspecific morphological differences between F. lantianensis and F. strigata, in addition to some intraspecific variations within each species. Here we preliminarily suggest that the previously defined Flabellophyton should be subdivided into 2 genera at least: one marked by the dark transverse striated structure, and the other without. This recharacterization and reclassification work still needs further careful observation and comprehensive analysis with large number of flabeilate fossils combining morphology, structure, population, and community-ecology study. 展开更多
关键词 Lantian biota Flabellophyton morphological analysis geometric morphometrics
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Glacier mapping based on Chinese high-resolution remote sensing GF-1 satellite and topographic data 被引量:1
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作者 LiLi Yan Jian Wang 《Research in Cold and Arid Regions》 CSCD 2019年第3期218-225,共8页
The precise glacier boundary is a fundamental requirement for glacier inventory,the assessment of climate change and water management in remote mountain areas.However,some glaciers in mountain areas are covered by deb... The precise glacier boundary is a fundamental requirement for glacier inventory,the assessment of climate change and water management in remote mountain areas.However,some glaciers in mountain areas are covered by debris.The high spatial resolution images bring opportunities in mapping debris-covered glaciers.To discuss the capability of Chinese GaoFen-1 satellite lacking the short wave infrared band and thermal infrared band in mapping glaciers,this study distinguished supraglacial terrain from surrounding debris by combining GaoFen-1(GF-1)wide-field-view(WFV)images,the ratio of the thermal infrared imagery and morphometric parameters(DEM and slope)with 30 m resolution.The overall accuracy of 90.94%indicated that this method was effective for mapping supraglacial terrain in mountain areas.Comparing this result with the combination of GF-1 WFV and low-resolution morphometric parameters shows that a high-quality DEM and the thermal infrared band enhanced the accuracy of glacier mapping especially debris-covered ice in steep terrain.The user's and producer's accuracies of glacier area were also improved from 89.67%and 85.95%to 92.83%and 90.34%,respectively.GF data is recommended for mapping heavily debris-covered glaciers and will be combined with SAR data for future studies. 展开更多
关键词 GLACIER MAPPING GaoFen-1 SATELLITE HIGH-QUALITY DEM MORPHOMETRIC parameters debris-covered glaciers
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Morphological and molecular characterization of the rice root-knot nematode, Meloidogyne graminicola, Golden and Birchfeild, 1965 occurring in Zhejiang, China 被引量:1
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作者 TIAN Zhong-ling Munawar Maria +2 位作者 Eda Marie Barsalote Pablo Castillo ZHENG Jing-wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第12期2724-2733,共10页
The rice root-knot nematode Meloidogyne graminicola is a severe pest of rice. In China, it was first reported from Hainan Province, and later from several other provinces. In the present study, a rice root-knot nemato... The rice root-knot nematode Meloidogyne graminicola is a severe pest of rice. In China, it was first reported from Hainan Province, and later from several other provinces. In the present study, a rice root-knot nematode population found from the rice cultivation areas of Zhejiang Province, China is characterized via molecular analysis using internal transcribed spacer(ITS) and cytochrome c oxidase subunit Ⅱ(coxⅡ)-16 S rRNA genes and scanning electron microscopy(SEM) observations of males and the second-stage juveniles. Morphometric data and molecular sequence comparisons for all M. graminicola populations occurring in China are also provided. The overall morphology of M. graminicola found in Zhejiang match well with the original description, though males have a slightly longer body and stylet, and a shorter tail, while the second-stage juvenile is also slightly longer than in the original description. This is the first report of M. graminicola from Zhejiang. Phylogenetic studies based on coxⅡ suggest that all the Chinese populations belong to Type B. This study expands knowledge of the increasing distribution and phylogenetic relationships of M. graminicola that occur in China. 展开更多
关键词 Meloidogyne graminicola morphology MORPHOMETRIC molecular RICE rDNA cytochrome c oxidase subunit (coxⅡ) China
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Quantitative Regionalization of W. Mujib-Wala Sub-Watersheds (Southern Jordan) Using GIS and Multivariate Statistical Techniques 被引量:2
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作者 Yahya Farhan Nisrin Al-Shaikh 《Open Journal of Modern Hydrology》 2017年第2期165-199,共35页
In arid and semi-arid watersheds, sustainable management of natural resources (i.e. land, water and ecological resources), and watershed management are crucial issues in applied morphometric studies. Geomorphometric p... In arid and semi-arid watersheds, sustainable management of natural resources (i.e. land, water and ecological resources), and watershed management are crucial issues in applied morphometric studies. Geomorphometric parameters and their interrelationships are of paramount importance in characterizing the morphology, topography, geology and structure, hydrological potential, and geomorphic evolution of such catchments. An analysis of spatial characteristics and morphological development of the demarcated 76 sub-watersheds related to W. Mujib-Wala catchment, was carried out using ASTER DEM and GIS. Multivariate statistical techniques such as Principal Component Analysis (PCA), Cluster Analysis (CA), and Discriminant Analysis (DA), were also employed to assess different aspects of drainage networks, and their morphometric properties. Principal Component Analysis (PCA) reduces the 22 morphometric parameters to five components, which explain 90.4% of total variance. The relationship of these components to the morphometric variables and to the individual sub-watersheds was evaluated, and then the degree of inter-correlation among the morphometric descriptors was explored. The 76 sub-watersheds were classified according to their individual relation to the components, and similarities in their morphometric characteristics. Regionalization of sub-watertsheds was achieved using hierarchical Cluster Analysis (CA). The validity of the resultant cluster groups was tested statistically by means of Discriminant Analysis. The present investigation provides information which highlights the benefit of geomorphometric analysis and multivariate statistics in modeling hydrological responses: i.e., surface runoff and sediment yield, hydrological assessment, water resources planning, and watershed management. Furthermore, the results can be useful for soil and water conservation planning, and assessment of flash floods potential. 展开更多
关键词 ASTER DEM MORPHOMETRIC Assessment Principal Component ANALYSIS (PCA) Cluster ANALYSIS (CA) DISCRIMINANT ANALYSIS (DA) GIS
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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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Prioritization of W. Mujib Catchment (South Jordan) through Morphometric and Discriminant Analysis, GIS, and RS Techniques 被引量:1
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作者 Yahya Farhan Dalal Zreqat +2 位作者 Ali Anbar Haifa Almohammad Sireen Alshawamreh 《Journal of Geoscience and Environment Protection》 2018年第4期141-171,共31页
GIS and remote sensing were utilized for prioritizing the W. Mujib catchment. Fifty three fourth-order sub-watersheds were prioritized based on morphometric analysis of linear and shape parameters. ASTER DEM (v.2), to... GIS and remote sensing were utilized for prioritizing the W. Mujib catchment. Fifty three fourth-order sub-watersheds were prioritized based on morphometric analysis of linear and shape parameters. ASTER DEM (v.2), topographical maps, and Arc GIS (10.1) software, have been employed to delineate the 53 sub-basins, to extract the drainage networks, and to compute the required basic, linear, and shape parameters, and to compile the necessary thematic maps such as elevation and slope categories. The land use/land cover map was generated using ERDAS Imagine (2015), LANDSAT 8 image, and supervised classification (Maximum Likelihood Method). Soil map was digitized using the Arc GIS tool. Each sub-basin is prioritized by assigning ranks based on the calculated compound parameter (Cp). The final score for each sub-basin is ascribed as per erosion threat. The 53 sub-watersheds were grouped into four categories of priority: very high (15 sub-basins, 28.3% of the total), high (17 sub-basins, 32% of the total), moderate (16 sub-basins, 30.2% of the total), and low (5 sub-basins, 9.5% of the total). Sub-basins categorized as very high and high priority (60.3% of the total) are subjected to high erosion risk, thus, creating an urgent need for applying soil and water conservation measures. The validity of the prioritized four groups was tested statistically by means of Discriminant Analysis (DA), and a significant difference was found between the four priority classes. A relatively complete separation exists between the recognized priority classes;thus, they are statistically valid, distinct, and different from each other. The present results intend to help decision makers pay sufficient attention to soil and water conservation programs, and to encourage tree plantation over the government-owned sloping land. Such procedures are essential in order to minimize soil erosion loss, and to increase soil moisture on farms, thus, reducing the impact of recurrent droughts and the possibility of flooding downstream. 展开更多
关键词 MORPHOMETRIC ANALYSIS PRIORITIZATION DISCRIMINANT ANALYSIS GIS Soil Conservation W. Mujib
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