Three common categories of bilateral asymmetry have been described: directional asymmetry, antisymmetry, and FA (fluctuating asymmetry). FA is the most subtle of the three types of asymmetry, and differs from the p...Three common categories of bilateral asymmetry have been described: directional asymmetry, antisymmetry, and FA (fluctuating asymmetry). FA is the most subtle of the three types of asymmetry, and differs from the patterns of the others in that paired structures tend to be symmetric in size. The analysis of FA allows to estimate the influence of stress factors on animal development and enables evaluation of resistance to stress. The aim of this work was to estimate the symmetry of skulls of a contemporary pure goat breed, as there is currently no study of FA as an estimate of individual quality for domestic goats. For this purpose, 11 landmarks were digitized in two dimensions from the crania of 24 adult goats (12 males and 12 females) belonging to the "White Rasquera" breed. The skulls showed nearly perfect bilateral symmetry. The low detected values of FA in skulls revealed a weak influence of developmental stress on this goat contemporary population and its strong ability to compensate stress.展开更多
The foramen magnum (FM), being a vital landmark at the base of the skull, includes interests to many fields of medicine. Many authors haverecounted the usefulness of the FM in gender determination. The emphasis of thi...The foramen magnum (FM), being a vital landmark at the base of the skull, includes interests to many fields of medicine. Many authors haverecounted the usefulness of the FM in gender determination. The emphasis of this study is to evaluate the shape and dimensions of the FM among males and females and to establish its role in sexual dimorphism using cone-beam computed tomography (CBCT). Furthermore, to evaluate the area and FM index (FMI) among males and females and finally to evaluate the differences in FM measurements if any in twodifferent regions of an Indian population. One hundred and ten CBCT scans (55 males and 55 females;age range, 20–80 years) were selectedfor this study. The sagittal diameter, transverse diameter, area, FMI, and circumference of FM were measured, and data were subjected to discriminant analysis for the evaluation of sexual dimorphism. The area of FM was the best discriminant parameter which was used to study the sexual dimorphism with an overall accuracy of 90.9%. It can be concluded that the reconstructed CBCT image provides valuable measurements for the FM and could be used for gender determination.展开更多
The Museum of Human Anatomy in Naples houses a collection of ancient Graeco-Roman crania.The aim of this study was to use multislice computed tomography(MSCT)to evaluate and objectively quantify potential differences ...The Museum of Human Anatomy in Naples houses a collection of ancient Graeco-Roman crania.The aim of this study was to use multislice computed tomography(MSCT)to evaluate and objectively quantify potential differences in cranial dimensions and shapes between ancient Graeco-Roman crania(n=36)and modern-day southern Italian crania(n=35)and then to characterize the cranial changes occurring over more than 2000 years,known as secular change.The authors used traditional metric criteria and morphometric geometry to compare shape differences between the sets of crania.Statistically significant differences in size between the ancient and modern crania included shorter facial length,narrower external palate,smaller minimum cranial breadth,shorter right and left mastoid processes,and wider maximum occipital and nasal breadth.The shape changes from the ancient to modern crania included a global coronal enlargement of the face and cranial diameters,with more anterior projection of the face at the anterior nasal spine,but also posterior projection at the glabella and the nasion.It is not possible to determine whether these differences result exclusively from secular changes in the cranium or from other factors,including a mix of secular change and other unknown factors.To the best of our knowledge,this is the first MSCT-based study to compare ancient Graeco-Roman and modern-day southern Italian crania and to characterize shape and size differences.展开更多
文摘Three common categories of bilateral asymmetry have been described: directional asymmetry, antisymmetry, and FA (fluctuating asymmetry). FA is the most subtle of the three types of asymmetry, and differs from the patterns of the others in that paired structures tend to be symmetric in size. The analysis of FA allows to estimate the influence of stress factors on animal development and enables evaluation of resistance to stress. The aim of this work was to estimate the symmetry of skulls of a contemporary pure goat breed, as there is currently no study of FA as an estimate of individual quality for domestic goats. For this purpose, 11 landmarks were digitized in two dimensions from the crania of 24 adult goats (12 males and 12 females) belonging to the "White Rasquera" breed. The skulls showed nearly perfect bilateral symmetry. The low detected values of FA in skulls revealed a weak influence of developmental stress on this goat contemporary population and its strong ability to compensate stress.
文摘The foramen magnum (FM), being a vital landmark at the base of the skull, includes interests to many fields of medicine. Many authors haverecounted the usefulness of the FM in gender determination. The emphasis of this study is to evaluate the shape and dimensions of the FM among males and females and to establish its role in sexual dimorphism using cone-beam computed tomography (CBCT). Furthermore, to evaluate the area and FM index (FMI) among males and females and finally to evaluate the differences in FM measurements if any in twodifferent regions of an Indian population. One hundred and ten CBCT scans (55 males and 55 females;age range, 20–80 years) were selectedfor this study. The sagittal diameter, transverse diameter, area, FMI, and circumference of FM were measured, and data were subjected to discriminant analysis for the evaluation of sexual dimorphism. The area of FM was the best discriminant parameter which was used to study the sexual dimorphism with an overall accuracy of 90.9%. It can be concluded that the reconstructed CBCT image provides valuable measurements for the FM and could be used for gender determination.
文摘The Museum of Human Anatomy in Naples houses a collection of ancient Graeco-Roman crania.The aim of this study was to use multislice computed tomography(MSCT)to evaluate and objectively quantify potential differences in cranial dimensions and shapes between ancient Graeco-Roman crania(n=36)and modern-day southern Italian crania(n=35)and then to characterize the cranial changes occurring over more than 2000 years,known as secular change.The authors used traditional metric criteria and morphometric geometry to compare shape differences between the sets of crania.Statistically significant differences in size between the ancient and modern crania included shorter facial length,narrower external palate,smaller minimum cranial breadth,shorter right and left mastoid processes,and wider maximum occipital and nasal breadth.The shape changes from the ancient to modern crania included a global coronal enlargement of the face and cranial diameters,with more anterior projection of the face at the anterior nasal spine,but also posterior projection at the glabella and the nasion.It is not possible to determine whether these differences result exclusively from secular changes in the cranium or from other factors,including a mix of secular change and other unknown factors.To the best of our knowledge,this is the first MSCT-based study to compare ancient Graeco-Roman and modern-day southern Italian crania and to characterize shape and size differences.