scholarly journals Studying the Shape Variations of the Back, the Neck, and the Mandibular Angle of Horses Depending on Specific Feeding Postures Using Geometric Morphometrics

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 763
Author(s):  
Federica Raspa ◽  
Angela Roggero ◽  
Claudia Palestrini ◽  
Martina Marten Canavesio ◽  
Domenico Bergero ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
Management Practices ◽  
Mixed Model ◽  
Principal Component ◽  
Canonical Variate ◽  
Long Term Effects ◽  
Mandibular Angle ◽  
Variate Analysis ◽  
The Right

The effects of specific feeding positions upon the horse’s shape variations of the back and neck postures as well as the variations of the mandibular angle have never been objectively studied. For this reason, geometric morphometrics was applied. Six horses, aged 14 ± 8 years (mean ± standard deviation, SD), were video-recorded while using three different feeding positions: on the ground—control position (CP); neck held 15 ± 3° below withers height with low hay net position (LP); neck held 15 ± 3° above withers height with high hay net position (HP). Data were analyzed using principal component analysis (PCA), multivariate analysis of variance (MANOVA), and partial least squares (PLS). A mixed model procedure was applied to evaluate differences in the magnitude of the mandibular angle. Whilst differences between individual horses were confirmed by canonical variate analysis (CVA), PCA analysis showed that a characteristic feeding position could also be identified on a group level. During the HP hay net position, the back and neck postures as well the mandibular angle were different compared to those exhibited by horses feeding from CP. In LP hay net position, the back posture more closely resembled those exhibited while feeding from CP; however, no similarity between LP and CP was found for neck posture and mandibular angle. Since only a few degrees of variation of the feeding position can influence back and neck postures, this aspect should be further investigated. The right compromise between horse welfare, horse safety, and management practices need to be further explored and long-term effects should be investigated.

scholarly journals Leaf geometric morphometrics among populations of Dalbergia ecastaphyllum (L.) Taub.

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Daniel Vieira de Morais ◽  
Lorena Andrade Nunes ◽  
Vandira Pereira da Mata ◽  
Maria Angélica Pereira de Carvalho Costa ◽  
Geni da Silva Sodré ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Geometric Morphometrics ◽  
Cross Validation ◽  
Abiotic Factors ◽  
Principal Component ◽  
Canonical Variate ◽  
Validation Test ◽  
Significant Difference ◽  
Variate Analysis ◽  
Geographical Distances

Leaves are plant structures that express important traits of the environment where they live. Leaf description has allowed identification of plant species as well as investigation of abiotic factors effects on their development, such as gases, light, temperature, and herbivory. This study described populations of Dalbergia ecastaphyllum through leaf geometric morphometrics in Brazil. We evaluated 200 leaves from four populations. The principal component analysis (PCA) showed that the first four principal components were responsible for 97.81% of variation. The non-parametric multivariate analysis of variance (NPMANOVA) indicated significant difference between samples (p = 0.0001). The Mentel test showed no correlation between geographical distances and shape. The canonical variate analysis (CVA) indicated that the first two variables were responsible for 96.77 % of total variation, while the cross-validation test showed an average of 83.33%. D. ecastaphyllum leaves are elliptical and ovate.

scholarly journals Comparison of Wing, Ovipositor, and Cornus Morphologies between Sirex noctilio and Sirex nitobei Using Geometric Morphometrics

Insects ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 84
Author(s):  
Ming Wang ◽  
Lixiang Wang ◽  
Ningning Fu ◽  
Chenglong Gao ◽  
Tegen Ao ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
North Africa ◽  
Principal Component ◽  
Canonical Variate ◽  
Native Range ◽  
Sirex Noctilio ◽  
Variate Analysis ◽  
Global Presence ◽  
And Cluster Analysis ◽  
Taxonomic Studies

Sirex noctilio F. (Hymenoptera: Siricidae) is an invasive woodwasp from Europe and North Africa. Globalization has led to an expanding global presence in pine forests. S. noctilio has been previously introduced outside of its native range and now co-occurs in trees with native S. nitobei Matsumura (first discovered in 2016). Damage to Pinus sylvestris var. mongolica Litv in northeast China can be attributed to two types of woodwasp. To distinguish the two species by the traditional taxonomic morphology, we mainly differentiate the color of the male’s abdomen and the female’s leg. There remains intraspecific variation like leg color in the delimitation of related genera or sibling species of Sirex woodwasps. In this study, we used landmark-based geometric morphometrics including principal component analysis, canonical variate analysis, thin-plate splines, and cluster analysis to analyze and compare the wings, ovipositors, and cornus of two woodwasps to ascertain whether this approach is reliable for taxonomic studies of this group. The results showed significant differences in forewing venation and the shapes of pits in the middle of ovipositors among the two species, whereas little difference in hindwings and cornus was observed. This study assists in clarifying the taxonomic uncertainties of Siricidae and lays a foundation for further studies of the interspecific relationships of the genus Sirex.

scholarly journals Differentiation of Five Species of Megachile (Hymenoptera: Megachilidae), based on Wing Shape

2016 ◽  
Vol 60 (2) ◽  
pp. 41-50 ◽  
Author(s):  
Shahram Falamarzi ◽  
Behzad Habibpour ◽  
Mohammad S. Mossadegh ◽  
Alireza Monfared
Keyword(s):  
Geometric Morphometrics ◽  
Cross Validation ◽  
Principal Component ◽  
Wing Shape ◽  
Canonical Variate ◽  
Effective Technique ◽  
Validation Test ◽  
Variate Analysis ◽  
Clear Differentiation ◽  
Respective Species

Abstract In the present work we used landmark-based geometric morphometrics to compare the wing shapes of five species of Megachile (belonging to three subgenera) to confirm whether this technique may be used reliably for differentiation of this group. Analyses of wing shape by the use of principal component analysis (PCA), and canonical variate analysis (CVA) led to a clear differentiation among species. We found a close phenotypic similarity in wing shape between M. albisecta (belonging to the subgenus Creightonella) and M. picicornis (belonging to the subgenus Eutricharaea). According to the results of UPGMA, a higher degree of divergence between M. farinosa (belonging to the subgenus Pseudomegachile) and species belonging to other subgenera, was detected. The results of a cross-validation test indicated that geometric morphometrics is an effective technique to use for distinguishing between Megachile species. The reliability rate of this technique was between 85.71-100%. Using only two submarginal cell landmarks for generating shape variables, the cross-validation test correctly assigned individuals to their respective species, with a 92.85-100% reliability rate. Significant differences in wing size were obtained among the analysed species.

scholarly journals Morphological Discrimination of Greek Honey Bee Populations Based on Geometric Morphometrics Analysis of Wing Shape

2014 ◽  
Vol 58 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Leonidas Charistos ◽  
Fani Hatjina ◽  
Maria Bouga ◽  
Mica Mladenovic ◽  
Anastasios D. Maistros
Keyword(s):  
Principal Component Analysis ◽  
Geometric Morphometrics ◽  
Honey Bee ◽  
Principal Component ◽  
Component Analysis ◽  
Canonical Variate Analysis ◽  
Procrustes Analysis ◽  
Canonical Variate ◽  
Wing Vein ◽  
Variate Analysis

Abstract Honey bees collected from 32 different localities in Greece were studied based on the geometric morphometrics approach using the coordinates of 19 landmarks located at wing vein intersections. Procrustes analysis, principal component analysis, and Canonical variate analysis (CVA) detected population variability among the studied samples. According to the Principal component analysis (PCA ) of pooled data from each locality, the most differentiated populations were the populations from the Aegean island localities Astypalaia, Chios, and Kythira. However, the populations with the most distant according to the canonical variate analysis performed on all measurements were the populations from Heraklion and Chania (both from Crete island). These results can be used as a starting point for the use of geometric morphometrics in the discrimination of honey bee populations in Greece and the establishment of conservation areas for local honey bee populations.

scholarly journals QOL-09. WHOLE-BRAIN WHITE MATTER NETWORK CONNECTIVITY IS DISRUPTED BY PEDIATRIC BRAIN TUMOR TREATMENT

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii432-iii432
Author(s):  
Adeoye Oyefiade ◽  
Kiran Beera ◽  
Iska Moxon-Emre ◽  
Jovanka Skocic ◽  
Ute Bartels ◽  
...  
Keyword(s):  
White Matter ◽  
Pediatric Brain Tumor ◽  
Pediatric Brain Tumors ◽  
Magnetic Resonance Images ◽  
Long Term Effects ◽  
Brain White Matter ◽  
The Right ◽  
Pediatric Brain ◽  
Betweeness Centrality

Abstract INTRODUCTION Treatments for pediatric brain tumors (PBT) are neurotoxic and lead to long-term deficits that are driven by the perturbation of underlying white matter (WM). It is unclear if and how treatment may impair WM connectivity across the entire brain. METHODS Magnetic resonance images from 41 PBT survivors (mean age: 13.19 years, 53% M) and 41 typically developing (TD) children (mean age: 13.32 years, 51% M) were analyzed. Image reconstruction, segmentation, and node parcellation were completed in FreeSurfer. DTI maps and probabilistic streamline generation were completed in MRtrix3. Connectivity matrices were based on the number of streamlines connecting two nodes and the mean DTI (FA) index across streamlines. We used graph theoretical analyses to define structural differences between groups, and random forest (RF) analyses to identify hubs that reliably classify PBT and TD children. RESULTS For survivors treated with radiation, betweeness centrality was greater in the left insular (p < 0.000) but smaller in the right pallidum (p < 0.05). For survivors treated without radiation (surgery-only), betweeness centrality was smaller in the right interparietal sulcus (p < 0.05). RF analyses showed that differences in WM connectivity from the right pallidum to other parts of the brain reliably classified PBT survivors from TD children (classification accuracy = 77%). CONCLUSIONS The left insular, right pallidum, and right inter-parietal sulcus are structurally perturbed hubs in PBT survivors. WM connectivity from the right pallidum is vulnerable to the long-term effects of treatment for PBT.

Inhibition of post-partum maternal behaviour in the rat by injecting an oxytocin antagonist into the cerebral ventricles

1987 ◽  
Vol 112 (2) ◽  
pp. 275-282 ◽  
Author(s):  
E. van Leengoed ◽  
E. Kerker ◽  
H. H. Swanson
Keyword(s):  
Wistar Rats ◽  
Post Partum ◽  
Rapid Onset ◽  
Maternal Behaviour ◽  
Cerebral Ventricles ◽  
Long Term Effects ◽  
Nesting Material ◽  
The Right ◽  
Oxytocin Antagonist

ABSTRACT Endogenous oxytocin released into the brain at parturition may stimulate the onset of maternal behaviour. In this study an attempt was made to block spontaneous maternal behaviour following natural delivery in Wistar rats by the injection of an antagonist of oxytocin into the cerebral ventricles. The analogue antagonist, d(CH2)5-8-ornithine-vasotocin, was administered by injection into a chronically implanted cannula in the right lateral ventricle at hourly intervals, beginning immediately after the expulsion of the first pup. The antagonist did not interfere with the normal progress of parturition or birth-related behaviours. After delivery of the last pup, mothers rested for 40 min in the test cage with the pups having been removed. Four pups and standard nesting material were then presented. Latency to pup carrying and duration of pup manipulation, nest building, and time spent on the nest with the pups, as well as duration of autogrooming and general activity were determined. Saline-injected controls started gathering the pups immediately and usually showed all elements of maternal behaviour within 10 min. Antagonist-treated mothers showed a marked delay in the onset of pup grouping and other maternal behaviours. At the end of 1 h, two out of six mothers had not yet picked up a single infant. Pups left overnight with their mothers were gathered into the nest and suckled, and no long-term effects of the antagonist were evident on retesting. The effectiveness of oxytocin antagonist in suppressing the rapid onset of post-partum maternal behaviour supports the hypothesis that centrally released oxytocin is involved in this process. It is noteworthy that these effects were obtained in Wistar rats, a strain in which oxytocin has failed to accelerate responsiveness to pups in virgin females. J. Endocr. (1987) 112, 275–282

scholarly journals Dynamic CT Scan of the Normal Scapholunate Joint in a Clenched Fist and Radial and Ulnar Deviation

Hand ◽  
2017 ◽  
Vol 13 (6) ◽  
pp. 666-670 ◽  
Author(s):  
Paul M. Kelly ◽  
John G. Hopkins ◽  
Andrew J. Furey ◽  
Daniel S. Squire
Keyword(s):  
Ct Scan ◽  
Range Of Motion ◽  
Ct Imaging ◽  
Dynamic Ct ◽  
Long Term Effects ◽  
Ulnar Deviation ◽  
Left Wrist ◽  
The Right ◽  
User Friendly

Background: Injuries to the scapholunate can have severe long-term effects on the wrist. Early detection of these injuries can help identify pathology. The purpose of this study was to evaluate the motions of the scapholunate joint in normal wrists in a clenched fist and through radial and ulnar deviation using novel dynamic computed tomography (CT) imaging. Methods: Fifteen participants below 40 years of age consented to have their wrist scanned. Eight participants were randomized to have the right wrist scanned and 7 the left wrist. Volunteers were positioned at the back of the gantry with the wrist placed on the table, palmar side down. Participants began with the hand in a relaxed fist position and then proceeded through an established range of motion protocol. Dynamic CT imaging was captured throughout the range of motion. Results: The movement in the healthy scapholunate joint through a clenched fist and radial and ulnar deviation is minimal. The averages were 1.19, 1.01, and 0.95 mm, representing the middle, dorsal, and volar measurements, respectively. Conclusions: This novel dynamic CT scan of the wrist is a user-friendly way of measuring of the scapholunate distance, which is minimal in the normal wrist below 40 years of age.

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