Analysis of function in the absence of extant functional homologues: a case study using mesotheriid notoungulates (Mammalia)

Paleobiology ◽  
2007 ◽  
Vol 33 (2) ◽  
pp. 227-247 ◽  
Author(s):  
Bruce J. Shockey ◽  
Darin A. Croft ◽  
Federico Anaya
Keyword(s):  
Morphological Traits ◽  
Principal Component ◽  
Axial Skeleton ◽  
Estimating Function ◽  
Analog Method ◽  
Principal Component Analyses ◽  
Analysis Of Function ◽  
Functional Homologues ◽  
Discriminant Function Analyses

We use two approaches to test hypotheses regarding function in a group of extinct mammals (Family Mesotheriidae, Order Notoungulata) that lack any close extant relatives: a principle-derived paradigm method and empirically derived analog method. Metric and discrete morphological traits of mesotheriid postcranial elements are found to be consistent with the morphology predicted by a modified version of Hildebrand's paradigm for scratch diggers. Ratios of in-force to out-force lever arms based on skeletal elements indicate that the mesotheriids examined had limbs modified for high out-forces (i.e., they were “low geared”), consistent with the digging hypothesis. Other mesotheriid characters, such as cleft ungual phalanges, a curved olecranon, and a highly modified pelvis (with extra vertebrae incorporated into the sacrum and fusion between the ischium and the axial skeleton) are regarded as being functionally significant for digging and also occur in a variety of extant diggers. Analog methods indicate that mesotheriids share numerous traits common to a variety of extant diggers. Principal component analyses of postcranial elements indicate that mesotheriids consistently share morphometric space with larger extant fossorial mammals: aardvark, anteaters, wombats, and badger. Likewise, discriminant function analyses categorized mesotheriids as fossorial, though imperfectly analogous to the extant diggers analyzed. Thus, both theory-driven and empirically derived methods of estimating function in these extinct taxa support a digging hypothesis for the mesotheriids examined. Adaptations for digging in both the forelimb and sacropelvic functional complexes of mesotheriids provide independent support for the fossorial hypothesis.

scholarly journals Genome Size Unaffected by Variation in Morphological Traits, Temperature, and Precipitation in Turnip

2019 ◽  
Vol 9 (2) ◽  
pp. 253 ◽  
Author(s):  
Supriyo Basak ◽  
Xudong Sun ◽  
Guangyan Wang ◽  
Yongping Yang
Keyword(s):  
Genome Size ◽  
Evolutionary Biology ◽  
Morphological Traits ◽  
Environmental Changes ◽  
Principal Component ◽  
Adaptive Significance ◽  
Temperature And Precipitation ◽  
The World ◽  
Principal Component Analyses ◽  
Organismal Complexity

Genome size (GS) was proposed as proxy for gross phenotypic and environmental changes in plants. GS organismal complexity is an enigma in evolutionary biology. While studies pertaining to intraspecific GS variation are abundant, literatures reporting the adaptive significance of GS are largelymissing. During food shortage, Brassica rapa var. rapa (turnip) is used as food and fodder for sustaining the livelihood of residents in the Qinghai Tibetan Plateau (QTP), which is also known as “the roof of the world”. Thus, climatic extremities make this region a natural environment to test adaptive significance of GS variation in turnip landraces. Therefore, from the QTP and its adjacent regions (the Hengduanshan and the Himalayas), we investigated adaptive evolution of GS in turnip landraces. Tuber diameter of turnip landraces was found to be significantly correlated with most of the environmental factors. GS was also shown not to be associated with morphological traits, temperature, and precipitation. Moreover, principal component analyses based on the whole dataset trisected the landraces into three distinct populations based on landrace usage—Hengduanshan, QTP, and the Himalayas. Nonetheless, our cumulative dataset showed evidence of adaptation of turnip landrace to different environments throughnonassociated genomic and phenomic plasticity.

scholarly journals Fast diffusion kurtosis mapping of human brain at 7 Tesla with hybrid principal component analyses

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Fangrong Zong ◽  
Jiaxin Du ◽  
Xiaofeng Deng ◽  
Xubin Chai ◽  
Yan Zhuo ◽  
...  
Keyword(s):  
Human Brain ◽  
Principal Component ◽  
7 Tesla ◽  
Fast Diffusion ◽  
Principal Component Analyses ◽  
Diffusion Kurtosis

scholarly journals Multitemporal–Multispectral UAS Surveys for Archaeological Research: The Case Study of San Vincenzo Al Volturno (Molise, Italy)

2021 ◽  
Vol 13 (14) ◽  
pp. 2719
Author(s):  
Nicodemo Abate ◽  
Alessia Frisetti ◽  
Federico Marazzi ◽  
Nicola Masini ◽  
Rosa Lasaponara
Keyword(s):  
Middle Ages ◽  
Principal Component ◽  
Archaeological Site ◽  
Archaeological Sites ◽  
Medieval Art ◽  
Archaeological Data ◽  
History Of ◽  
Close Range ◽  
Low Altitude

Unmanned aerial vehicles are currently the most used solution for cultural heritage in the field of close range and low altitude acquisitions. This work shows data acquired by multitemporal and multispectral aerial surveys in the archaeological site of San Vincenzo al Volturno (Molise, Italy). The site is one of the most important medieval archaeological sites in the world. It is a monastic settlement that was particularly rich during the early Middle Ages, and is famous for its two full-frescoed crypts which represent a milestone in the history of medieval art. Thanks to the use of multispectral aerial photography at different times of the year, an area not accessible to archaeological excavation has been investigated. To avoid redundancy of information and reduce the number of data to be analysed, a method based on spectral and radiometric enhancement techniques combined with a selective principal component analysis was used for the identification of useful information. The combination of already published archaeological data and new remote sensing discoveries, has allowed to better define the situation of the abbey during the building phases of the 8th/9th century and 11th century, confirming and adding new data to the assumptions made by archaeologists.

scholarly journals Multi-objective parametrization of interatomic potentials for large deformation pathways and fracture of two-dimensional materials

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xu Zhang ◽  
Hoang Nguyen ◽  
Jeffrey T. Paci ◽  
Subramanian K. R. S. Sankaranarayanan ◽  
Jose L. Mendoza-Cortes ◽  
...  
Keyword(s):  
Large Deformation ◽  
Functional Form ◽  
Principal Component ◽  
Interatomic Potentials ◽  
Two Dimensional ◽  
Multi Objective ◽  
Multi Objective Genetic Algorithm ◽  
Two Dimensional Materials ◽  
Definition Of

AbstractThis investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways. It incorporates a multi-objective genetic algorithm, training and screening property sets, and correlation and principal component analyses. The framework enables iterative definition of properties in the training and screening sets, guided by correlation relationships between properties, aiming to achieve optimal parametrizations for properties of interest. Specifically, the performance of increasingly complex potentials, Buckingham, Stillinger-Weber, Tersoff, and modified reactive empirical bond-order potentials are compared. Using MoSe2 as a case study, we demonstrate good reproducibility of training/screening properties and superior transferability. For MoSe2, the best performance is achieved using the Tersoff potential, which is ascribed to its apparent higher flexibility embedded in its functional form. These results should facilitate the selection and parametrization of interatomic potentials for exploring mechanical and phononic properties of a large library of two-dimensional and bulk materials.

scholarly journals Development of Performance Evaluation Indicators for Table Grape Packaging Units

2021 ◽  
Vol 13 (4) ◽  
pp. 2177
Author(s):  
Edson Kogachi ◽  
Adonias Ferreira ◽  
Carlos Cavalcante ◽  
Marcelo Embiruçu
Keyword(s):  
Performance Evaluation ◽  
Standard Deviation ◽  
Process Management ◽  
Principal Component ◽  
Table Grape ◽  
Data Envelopment ◽  
Table Grapes ◽  
Speed Performance ◽  
The Cost

In order to improve the process management of table grape packaging, its performance should be evaluated. However, the literature on performance evaluation indicators is scarce. To address this research gap, we propose a method for the development of performance evaluation indicators for table grape packaging units, which are characterized by labor-intensive and highly seasonal production processes in the agro-economic sector. The stages include the following: contextualizing table grape packaging units, selecting the performance objectives, selecting techniques to be used in the development of the indicators, and applying the method to the packaging units of table grapes. The techniques adopted in the development of the indicators aimed at the cost, quality, flexibility, reliability, and speed performance objectives were data envelopment analysis, principal component analysis, quantification of the batch, compliance with the program within the established deadline, and measurement of the execution time of the batch, respectively. The results obtained in the case study demonstrate that the correlations between the performance indicators do not indicate the need to disregard any of them. Furthermore, the standard deviation values for each indicator are similar. Thus, both results of correlations and standard deviation confirm the importance of the indicators chosen for the performance evaluation of table grape packaging.

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