elliptic fourier analysis
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2021 ◽  
Author(s):  
Erica Cantor ◽  
Krista Latham ◽  
Stephen Nawrocki

Sex estimation is important in the creation of a biological profile for unidentified human remains, as positive identification cannot occur until the decedent’s biological traits have been determined and the range of possible matches has been narrowed. The pubic bone is cited as one of the best indicators of sex due to the constraints of childbirth. Current methods that use the pubic bone for sex estimation, however, rely on poorly defined and subjective observations that are susceptible to inter-and intraobserver error. Additionally, many of the methods currently in use are based on North American populations and thus may not necessarily model the variation seen in other populations around the globe. The aim of this study is to gain a better understanding of variation in pubic bone shape in Hispanic populations by separating the influences of sex, ancestry, and age at death. A total of 164 pubic bones from North American Hispanic and Chilean individuals were compared to 287 pubic bones from individuals of Euro-American ancestry from North American collections, using Elliptic Fourier analysis (EFA) of photographs, principal component analysis, and ANCOVA. EFA generated five effective principal components that collectively describe approximately 95% of the variation in the shape of the pubic body. Sex, age at death, and ancestry were all found to significantly influence shape but explained only 25% of the overall variation. The remaining 75% is likely influenced by variables that cannot be controlled for in anthropological analysis, underscoring how little variance in skeletal morphology is actually explainable.


2021 ◽  
Vol 8 ◽  
Author(s):  
Joana Vasconcelos ◽  
Alba Jurado-Ruzafa ◽  
José Luis Otero-Ferrer ◽  
Antoni Lombarte ◽  
Rodrigo Riera ◽  
...  

The genetic polymorphism and phenotypic variation are key in ecology and evolution. The morphological variability of the contour of fish otoliths has been extensively used for the delimitation of stocks. These studies are conventionally based on average phenotype using elliptic Fourier analysis and lineal discriminant analysis as classifier. Considering new analytical options, such as the wavelet transform and non-parametric algorithms, we here analyzed the otolith shape of Trachurus picturatus (blue jack mackerel) from mainland Portugal, Madeira, and the Canaries. We explore the phenotypic variation throughout a latitudinal gradient, establish a hypothesis to explain this variability based on the reaction norms, and determine how the use of average phenotype and/or morphotypes influences in the delimitation of stocks. Four morphotypes were identified in all regions, with an increase of phenotypes in warmer waters. The findings demonstrated that stocks were clearly separated with classification rates over 90%. The use of morphotypes, revealed seasonal variations in their frequencies and per region. The presence of shared phenotypes in different proportions among fishing grounds may open new management approaches in migratory species. These results show the importance of the phenotypic diversity in fisheries management.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Bünyamin Demir ◽  
Bahadır Sayıncı ◽  
Mehmet Yaman ◽  
Ahmet Sümbül ◽  
Ercan Yıldız ◽  
...  

Abstract In the present study, the biochemical composition and shape and dimensional traits of 25 rosehip (Rosa canina) genotypes were investigated. The shape and dimensional traits were determined by image processing technique. Seed-propagated rosehip genotypes belonging to R. canina were collected from the natural flora of Mesudiye (Ordu) and Talas (Kayseri) districts. Antioxidant activity (39.510–72.673 mmol · kg−1), total flavonoids (287.80–1,686.20 mg quercetin equivalent (QE) · kg−1) and total phenolics (38,519.40–79,080.60 mg gallic acid equivalent · kg−1) of the genotypes exhibited large variations. Width (12.2 mm) and thickness (12.5 mm) of fruits averages were found to be close to each other. The genotypes exhibited fruit lengths between 12.0 mm and 29.5 mm. Average projected area at horizontal orientation (179.7 mm2) was greater than the projected area at vertical orientation (120.4 mm2). Sphericity average was calculated as 71.4%. According to principal component (PC) analysis, the most important dimensional traits discriminating genotypes from each other were identified as surface area, geometric mean diameter and volume. In terms of shape attributes, distinctive differences were observed in sphericity, circularity, elongation and surface closure rates (SCR) of the genotypes. According to elliptic Fourier analysis (EFA), genotypes look like a sphere. In terms of shape, there were long, spherical, flat bottomed, pointed bottomed and asymmetric-looking genotypes indicating how environment and genotype affect the fruit shape. The greatest shape variation was transverse contraction and expansion. According to the clustering analysis for shape attributes, rosehip genotypes were classified into six groups. Dendrogram, scatter plots of linear discriminant analysis and paired comparison test results put forth the shape differences of the genotype successfully.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1528
Author(s):  
Muhammed Kupe ◽  
Bahadır Sayinci ◽  
Bünyamin Demir ◽  
Sezai Ercisli ◽  
Kürşat Alp Aslan ◽  
...  

In this study, berry dimensions and shape traits, which are important for the design of the grape processing system and the classification of 10 different grape varieties grown in same ecological conditions (‘Ata Sarısı’, ‘Barış’, ‘Dımışkı’, ‘Hatun Parmağı’, ‘Helvani’, ‘Horoz Karası’, ‘Hönüsü’, ‘İtalia’, ‘Mevlana Sarısı’, and ‘Red Globe’) were determined; differences between the varieties were identified with the use of discriminant analysis. The largest grape varieties were identified as ‘Ata Sarısı’ and ‘Red Globe’. The ‘Red Globe’ and ‘Helvani’ varieties had geometrically sphere-like shape. The ‘Barış’ variety had the lowest size averages. According to elliptic Fourier analysis, the primary source of shape variation was ellipse and sphere-looking varieties. However, shape variation was seen due to the existence of a small number of drop-like varieties. According to discriminant analysis, shape differences of the varieties were defined by two discriminant functions. Based on these discriminant functions, the greatest classification performance was achieved for ‘Mevlana Sarısı’ and ‘Dımışkı’. In scatter plots, three shape definitions (sphere, ellipse, and drop) were made for grape varieties. Cluster analysis revealed 4 sub-groups. The first sub-group included the ‘Mevlana Sarısı’ variety; the second sub-group included the ‘Hönüsü’, ‘Hatun Parmağı’, ‘Dımışkı’, and ‘Horoz Karası’ varieties; the third sub-group included the ‘Ata Sarısı’ variety; the fourth sub-group included the ‘Barış’, ‘Helvani’, ‘İtalia’, and ‘Red Globe’ varieties. The variety in the first group had a geometrically ellipse-like shape, the largest length, and the smallest width. The size data were the smallest for the second sub-group. The third sub-group, with the ellipse-like shape, had the large size data. The grape varieties the closest to the sphere were classified in the fourth group, and these varieties had the large sizes.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1350
Author(s):  
Muhammed Kupe ◽  
Bahadır Sayıncı ◽  
Bunyamin Demir ◽  
Sezai Ercisli ◽  
Mojmir Baron ◽  
...  

Morphology is the most visible and distinct character of plant organs and is accepted as one of the most important tools for plant biologists, plant breeders and growers. A number of methods based on plant morphology are applied to discriminate in particular close cultivars. In this study, image processing analysis was used on 20 grape cultivars (“Amasya beyazı“, “Antep karası“, “Bahçeli karası”, “Çavuş“, “Cevşen“, “Crimson“, “Dimrit“, “Erenköy beyazı“, “Hafızali“, “Karaşabi“, “Kırmızı“, “İzabella (Isabella) “, “Morşabi“, “Müşgüle“, “Nuniya“, “Royal“, “Sultani çekirdeksiz (Sultanina)“, “Yalova incisi“, “Yerli beyazv“, “Yuvarlak çekirdeksiz“) to classify them. According to image processing analysis, the longest and the greatest projected area values were observed in “Antep karası“ cultivar. The “Sultani çekirdeksiz“ cultivar had the least geometric mean diameter. The greatest sphericity ratios were observed in “Yerli beyaz“, “Erenköy beyazı“ and “Amasya beyazı“ cultivars. According to principal component analysis, dimensional attributes were identified as the most significant source of variation discriminant grape cultivars from each other. Morphological differences between the cultivars were explained by sphericity and elongation variables. According to elliptic Fourier analysis (EFA) results, grape morphology largely looks like ellipse and sphere. However, there are some cultivars that look similar to a water drop. The cultivars with similar morphology were identified by a pair-wise comparison test conducted with the use of linear discriminant analysis, and they were presented in a scatter plot. According to cluster analysis, present grape cultivars were classified into seven sub-groups, which indicated great diversity.


2021 ◽  
Author(s):  
Mihailo Radinović ◽  
Irina Kajtez

An important aspect of prismatic blade production is the choice of a knapping technique. This study tests the utility of elliptic Fourier analysis (EFA) for discriminating between different knapping techniques and offers a new perspective on blade variability. Our results indicate that there is an overlap in the outline shape and symmetry of individual blades produced by direct percussion, indirect percussion, and pressure debitage. Nevertheless, the EFA points out certain group-level differences regarding the shape and regularity of blade outlines and yields classification accuracy which is comparable to the previously proposed quantitative approaches for distinguishing blades produced by different knapping techniques. However, a more detailed analysis of technique-related factors shows that the emerging variability of blade outlines is more complex and that tripartite division might not always be suitable for reconstructing the past knapping behavior. We discuss the advantages and disadvantages of this method, and how it could complement the standard technological analysis in exploring and explaining blade variability.


2020 ◽  
Vol 45 (4) ◽  
pp. 921-930
Author(s):  
Juliana Alencar ◽  
André Luiz Borba do Nascimento ◽  
Paulo Duarte-Neto ◽  
Maria Teresa Buril

Abstract—Daustinia montana (Convolvulaceae) is the only species of the genus, and is notable for its wide leaf variability. To understand whether this plasticity is correlated with the distribution of the species, linear morphometric and leaf contour analyses were performed. Specimens from herbaria were photographed, and pre-established linear measurements were made. A multivariate analysis was then performed to test the strength of associations among morphological characteristics, climatic variables, and distribution of the species. Elliptic Fourier analysis based on 20 harmonics was used to generate shape descriptors, resulting in nine main components. With elliptic Fourier descriptors, a grouping tree was created that suggests the existence of six morphotypes in D. montana. Moreover, clustering analysis revealed two large groups distinguished mainly by leaf width. The present findings indicate that the morphotypes are strongly related to latitude and that other characteristics such as the type of indumentum are related to climatic variables.


2020 ◽  
Author(s):  
Somsanith Chonephetsarath ◽  
Chadchalerm Raksakoon ◽  
Suchada Sumruayphol ◽  
Jean-Pierre Dujardin ◽  
Rutcharin Potiwat

Abstract BackgroundPrevious publications revealed a clear taxonomic signal embedded in the external contour of the wings. Our study explored this signal also for internal cells of the wings, with the following question: do internal cells uniformly provide the same taxonomic information? MethodsOur study focused on four species, three of them of medical importance: Ae. aegypti, Ae. albopictus, Ae. scutellaris and Ve. dux, each of them represented by 30 female wings. Each cell was characterized for size and shape after an elliptic Fourier analysis. For each cell to be tentatively assigned to its respective species, i.e., to measure its amount of taxonomic information, we used the shape of the contour, not its size. ResultsWe showed that the taxonomic signal of shape was not uniformly spread among internal cells of the wing, ranging on average from 80% to 94%. Four internal cells out of six performed better than the external contour of the wing. The amount of taxonomic information of internal cells could not be related to their size nor to their shape complexity, but clearly depended on which species were compared. The closest species of our sample, Ae. albopictus and Ae. scutellaris, two species frequently found in the same water collections in Thailand, were almost perfectly separated (97%) by a single cell. ConclusionIt has already been said that the wing can be used for mosquito identification even if the whole body is not available, we showed that even partly damaged wings could contain extractable and more accurate taxonomic information.


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