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1.
吴秀杰 《人类学学报》2022,41(4):608-617
自20世纪40年代魏敦瑞提出北京猿人(周口店直立人)可能存在“暴力争斗”和“同类残食”的观点之后,引发了一些学者和科普大众对北京猿人是否为“食人族”的争论。由于原始化石标本在第二次世界大战期间丢失,本文以保存下来的周口店(ZKD)直立人头骨原始模型和素描图为研究材料,对魏敦瑞提出的具有创伤和人工切割痕迹的5件标本(ZKD II、ZKD VI、ZKD X、ZKD XI和ZKD XII)进行辨析。结果显示:1)ZKD X、ZKD XI、ZKD XII这3件标本的头盖部,有7处可以确定为生前遭受非致死性撞击导致的局部创伤;2)ZKD VI头盖骨残片周边的及中央区域的断痕,为个体生前遭受致死性的暴力打击导致;3)ZKD II和ZKD VI顶骨位置疑似人工切割痕迹的沟槽实际上是动物啃咬或自然因素导致的,北京猿人“同类残食”的观点在本文研究中没有得到证实。北京猿人头骨的创伤痕迹都位于头盖部,以顶骨居多,其次为额骨,符合人群之间暴力冲突产生创伤的位置。  相似文献   

2.
Fluctuating asymmetry is commonly used as a bioindicator of developmental stress. This study addresses asymmetry under nutritional/systemic stress in the human craniofacial skeleton and its utility as an indicator of developmental instability. Crania from the diachronic Christian cemeteries at Kulubnarti (Sudanese Nubia) were chosen as a model for nutrition/systemic stress. Previous studies indicate that individuals from the Early Christian cemetery were subjected to greater developmental stress when compared with individuals from the Late Christian cemetery. Therefore, crania from the Early Christian cemetery should display a greater magnitude of fluctuating asymmetry than crania from the Late Christian cemetery. Thirty adult crania of comparable age and sex were selected from each population. Landmark coordinates were digitized in two separate trials and averaged to minimize error. Euclidean distance matrix analysis (EDMA) was used to measure and compare the magnitude of fluctuating asymmetry in each sample. Results indicate that crania from the Early Christian cemetery display greater amounts of fluctuating asymmetry than those from the Late Christian cemetery, as predicted. The degree of fluctuating asymmetry for each linear distance is highly correlated between the cemeteries, suggesting that all humans may share common patterns of fluctuating asymmetry in the skull. In contrast, there is little correlation between magnitude of fluctuating asymmetry and length of linear distance, between-subject variability, or measurement error. These results support the hypothesis that poor nutrition/systemic stress increases developmental instability in the human skull and that increased fluctuating asymmetry constitutes morphological evidence of this stress.  相似文献   

3.
The anatomy and morphometry of venous values associated with the vasculature of the head of the duckling were studied using vascular corrosion casting and scanning electron microscopy. All valves encountered were bicuspid, and casts typically exhibited slight expansions at valve sinuses and deep slits at the sites of valve leaflets. The locations, numbers, and orientations of endothelial nuclei on all surfaces of the valves were clearly revealed by imprints in the casting resin. Endothelial cell densities were significantly higher on the surfaces of valve leaflets (about 10 cells/1,000 micron2) than on other venous surfaces (about 7 cells/1,000 micron2). Endothelial nuclei on the medial surface of the valve leaflet were oriented parallel to the long axis of the vessel, whereas those on the lateral surface were oriented perpendicular to that axis. The close proximities of valves in some vessels and the presence of anomalies such as the sharing of leaflets by adjacent valves were readily demonstrated with the corrosion-casting techniques. These methods provide a useful means for studying the fine, three-dimensional details of venous valve anatomy.  相似文献   

4.
The present paper resumes the theme taken up by Bonnevie in her studies of the embryonic development of dermatoglyphic systems. Relicts of the embryonic finger balls remain in later life (Fleischhacker) and influence the symmetry relationships of the terminal phalanges. Attention was, therefore, focussed on the connection between the asymmetry of terminal phalanges and that of the patterns. All loops and whorls with a different ridge count on the radial and on the ulnar side are asymmetrical. In order to determine the asymmetry of the terminal phalanges, casts were made of the fingers of 200 schoolchildren. Then, contour drawings were laid into various planes using the phalangograph (constructed on the same lines as the perigraph), and the plane of intersection of the two sides of the symmetry axis was determined planimetrically. A high correlation of r = 0·954 was established between the degree of asymmetry of the patterns and that of the terminal phalanges (cf. Figure 3).  相似文献   

5.
Orthodontic tooth movements are described as the differences between initial and final tooth positions. A computer based method for determination of tooth movements for different treatment methods was developed. A total of 20 casts of the upper jaw of patients treated with tooth positioners or fixed appliances were used as a basis for this study. Tooth movement was analysed on casts before (Ci) and after treatment (Cf). The casts were digitized either with a COMT or 3D laser scanning systems. After digitization, the models were superimposed in the palate by using a surface-surface matching algorithm. Tooth surfaces of the orthodontically moved teeth were segmented and determination of tooth movement was accomplished by matching the moved teeth from Ci to Cf. The resulting transformations delivered three dimensional information on translations and rotations. An accuracy of 0.2 mm in translations and 1 degree in rotations could be demonstrated, showing the different efficiency of treatment schemes.  相似文献   

6.
MRI and neurological findings in macrocephaly-cutis marmorata telangiectatica congenita syndrome: report of ten cases and review of the literature: We describe the clinical history and magnetic resonance imaging (MRI) findings in 10 children with the Macrocephaly-Cutis Marmorata Telangiectatica Congenita syndrome (M-CMTC--MIM 602501). This syndrome has recently been delineated within the general group of patients with Cutis Marmorata Telangiectatica (CMTC) as a distinct and easily recognisable entity. In contrast to most children with CMTC, patients with M-CMTC syndrome have a high risk of neurological abnormalities, such as hydrocephalus, megalencephaly, developmental delay and mental retardation. An MRI scan showed structural cerebral abnormalities in all of our patients, including megalencephaly, asymmetry of the cerebral hemispheres and abnormally increased signal of white matter. Seven patients also had Chiari type I malformation. Reviewing all reported cases, we propose appropriate surveillance for known complications.  相似文献   

7.
Every year, thousands of fatalities result from head injuries, the majority of which are sustained in automotive accidents. In this paper, an experimental study of the response of the human head to impact is presented. A rapid prototyped model of a human head was generated based on high-resolution magnetic resonance imaging (MRI) scan data. The physical model was subjected to low velocity impacts using a metallic pendulum and a sensitivity study was performed to explore the influence of various parameters, including mass and velocity of the impactor, on the response. The experimental response characteristics are compared with predictions from an analytical model as well as with numerical predictions from finite element (FE) models generated from the same MRI data set. The results from the experimental tests closely match those predicted by both the analytical and the FE models and thus provide us with substantive corroboration of all three approaches. The remarkable agreement obtained between the measured response characteristics of rapid-prototyped skulls and numerical (FE) models obtained from in vivo MRI data clearly demonstrates the potential use of rapid-prototyping to generate experimental models for head impact studies, and, more generally, for the study of the response of complex bio-structures to loading. In addition, the quantitative and qualitative accuracy of the predictions from the analytical model is clearly demonstrated by the FE and experimental corroboration. In particular, the analytical prediction that, as impact mass drops the impact duration becomes increasingly short, appears to be substantiated, which has important implications for the onset of high pressure and shear strain gradients in the brain with potentially deleterious effects.  相似文献   

8.
A separate analysis of ulnar and radial finger ridge-counts, obtained from 115 Aymara Indians (55 males and 60 females) of northern Chile, was performed. From these variables, directional asymmetry, fluctuating asymmetry, indices of bilateral asymmetry (√A2), and intraindividual diversity (s/√5) were calculated for each sex. The results show that most bimanual differences for the ridge-counts are not statistically significant in the Aymara, except for radial counts in female first and second fingers (right hand means are larger), while most ulnar-radial differences are highly significant in both sexes (radial values exceed ulnar ones). Most sex differences do not reach statistical significance, although males have more ridge-counts, lower directional asymmetry, somewhat lower fluctuating asymmetry, and lower indices of asymmetry and diversity than females. As fluctuating asymmetry is not larger in males, the dermatoglyphic findings do not indicate support for the hypothesis that males are less canalized than females. In accordance with the findings of other authors, interpopulation comparisons in the indices of asymmetry and diversity show ethnic differences. Both indices tend to be low in samples of African ancestry, high in samples of European origin, and intermediate in the Aymara, while Indian groups are characterized by high asymmetry and low diversity values. Moreover, the data reveal a geographical trend in that asymmetry and diversity values tend to decrease from the northern to the southern hemisphere in populations of Europe, the Middle East, and Africa, thus indicating greater ridge-count variability and heterogeneity among fingers in northern populations. It is assumed that this gradient primarily reflects different degrees of miscegenation and heterozygosity. Am J Phys Anthropol 105:377–393, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

9.
A method is described whereby three-dimensional co-ordinates of points on a cranium can be recorded in terms of azimuth, elevation and radial distance from a selected point. These co-ordinates can be used to create two-dimensional representations of single crania, the differences between many crania or growth stages of individuals or series of individuals. The co-ordinates can be used in more conventional analytic ways in the same way as cartesian co-ordinates.  相似文献   

10.
Orthodontic tooth movements are described as the differences between initial and final tooth positions. A computer based method for determination of tooth movements for different treatment methods was developed. A total of 20 casts of the upper jaw of patients treated with tooth positioners or fixed appliances were used as a basis for this study. Tooth movement was analysed on casts before (C i) and after treatment (C f). The casts were digitized either with a COMT or 3D laser scanning systems. After digitization, the models were superimposed in the palate by using a surface–surface matching algorithm. Tooth surfaces of the orthodontically moved teeth were segmented and determination of tooth movement was accomplished by matching the moved teeth from C i to C f. The resulting transformations delivered three dimensional information on translations and rotations. An accuracy of 0.2?mm in translations and 1 degree in rotations could be demonstrated, showing the different efficiency of treatment schemes.  相似文献   

11.
Near-infrared spectroscopy (NIRS) provides a unique method of monitoring infant brain function by measuring the changes in the concentrations of oxygenated and deoxygenated hemoglobin. During the past 10 years, NIRS measurement of the developing brain has rapidly expanded. In this article, a brief discussion of the general principles of NIRS, including its technical advantages and limitations, is followed by a detailed review of the role played so far by NIRS in the study of infant perception and cognition, including language, and visual and auditory functions. Results have highlighted, in particular, the developmental changes of cerebral asymmetry associated with speech acquisition. Finally, suggestions for future studies of neurocognitive development using NIRS are presented. Although NIRS studies of the infant brain have yet to fulfill their potential, a review of the work done so far indicates that NIRS is likely to provide many unique insights in the field of developmental neuroscience.  相似文献   

12.
The socioeconomic structure of an early medieval society from the Mikul?ice settlement (Czech Republic) was studied on the basis of an evaluation of the fluctuating and directional asymmetry (DA) of skulls. Two distinct inhabited regions, castle and sub‐castle, were compared. Fluctuating asymmetry (FA) was used as a bioindicator of environmental stress, which is thought to have been different in the Mikul?ice castle and sub‐castle regions. DA is consistent with biomechanical loading, and it was expected to reflect different subsistence patterns. The material consisted of 129 crania from what was presumed to be a higher socioeconomic class (Mikul?ice castle) and 71 crania from middle and lower socioeconomic classes (Mikul?ice sub‐castle). As a comparative sample, 138 crania from modern, lower socioeconomic classes (Pachner Collection) were used. The three‐dimensional coordinates of 68 landmarks were digitized and analyzed using geometric morphometrics. In terms of DA, the highest values were recorded in the sub‐castle sample and confirmed their lower socioeconomic position, with a grittier and lower protein diet compared with the castle sample. In terms of FA, distinctive differences between the sexes were found. In males, no differences were observed between castle and sub‐castle, and the lowest FA values were recorded. In females, significantly higher values of FA were found, surprisingly in the castle sample, comparable with the more stressed Pachner Collection. We suspect that the FA reflects a more varied population of castle females as a consequence of patrilocality, although environmental stress remains a possibility. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

13.
This study measures the correlation between within- and among-individual variance to gain a greater understanding of the relationship of the underlying mechanisms governing developmental stability and canalization. Twenty-six landmarks were digitized in three dimensions from the crania of 228 adult macaques from Cayo Santiago. The phenotypic variance between individuals was measured and divided into its genetic and environmental components using matriline information. Within-individual variance was measured as the fluctuating asymmetry between bilateral landmarks. We found positive and significant correlations between the phenotypic, environmental, and fluctuating asymmetry variances for interlandmark distances. We also found low but significant correspondences between the covariation structures of the three variability components using both Procrustes and interlandmark distance data. Therefore, we find that in macaque skulls traits that exhibit greater levels of asymmetry deviations also exhibit greater levels of environmental variance, and that the covariances of absolute symmetry deviations partly correspond to covariances of mean deviations at the individual level. These results suggest that the underlying processes that determine canalization and developmental stability are at least partly overlapping. However, the low correlations reported here are also evidence for a degree of independence between these variability components.  相似文献   

14.
By employing a version of industrial slush casting to conventional silicone rubber moulds and simultaneously applying internal pressure, accurate epoxy resin casts may be obtained, varying by less than 1.0% from the original. This is made possible by the construction of a machine which rotates the moulds through all axes. When applied to fossil crania these moulding and casting methods not only accurately reproduce the external morphology, but when access permits, simultaneously copy the endocranium. The dimensional accuracy is reproduced throughout for any given measurement. By using a variety of colouring methods these casts also produce replicas which closely approximate the appearance of the original.  相似文献   

15.
Three‐dimensional geometric morphometric techniques have been widely used in quantitative comparisons of craniofacial morphology in humans and nonhuman primates. However, few anatomical landmarks can actually be defined on the neurocranium. In this study, an alternative method is proposed for defining semi‐landmarks on neurocranial surfaces for use in detailed analysis of cranial shape. Specifically, midsagittal, nuchal, and temporal lines were approximated using Bezier curves and equally spaced points along each of the curves were defined as semi‐landmarks. The shortest paths connecting pairs of anatomical landmarks as well as semi‐landmarks were then calculated in order to represent the surface morphology between landmarks using equally spaced points along the paths. To evaluate the efficacy of this method, the previously outlined technique was used in morphological analysis of sexual dimorphism in modern Japanese crania. The study sample comprised 22 specimens that were used to generate 110 anatomical semi‐landmarks, which were used in geometric morphometric analysis. Although variations due to sexual dimorphism in human crania are very small, differences could be identified using the proposed landmark placement, which demonstrated the efficacy of the proposed method. Am J Phys Anthropol 151:658–666, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
This study aimed to test the performance of 3D digitizer, CT scanner, and surface scanner in detecting cranial fluctuating asymmetry. Sets of 32 landmarks (6 in the midline and 13 bilateral) were acquired from 14 archeological crania using a 3D digitizer, and from 3D models generated from a CT scanner and surface scanner using Viewbox 4. Levels of shape variation were analyzed in MorphoJ using Procrustes analysis of variance and Principal component analysis. Intra-observer error accounted for 1.7%, 1.8%, and 4.5% of total shape variation for 3D digitizer, CT scanner, and surface scanner respectively. Fluctuating asymmetry accounted for 15%–16% of total shape variation. Variation between techniques accounted for 18% of total shape variation. We found a higher level of missing landmarks in our surface scan data than for both 3D digitizer and CT scanner data, and both 3D model-based techniques sometimes obscured taphonomic damage. All three 3D techniques are appropriate for measuring cranial fluctuating asymmetry. We advise against combining data collected with different techniques.  相似文献   

17.
Spermatozoa of the shrew Suncus murinus, a mammal with abdominal testes, exhibit four unusual features: a giant acrosome; a dorsoventral asymmetry of their spermiation; a dorsoventral asymmetry of their head surface character; and also apparent surface maturity as they enter the epididymis. A Sertoli cell-periacrosomal cisternal complex envelops the giant acrosome during spermatid maturation. Spermiation is heraled by asymmetrical disorganization of the subplasmalemmal components of this complex and is completed by retraction of the Sertoli cell from the ventral and then the dorsal face of the spermatid head. This sequence or release is correlated with an asynchronous acquisition of negative surface charges on the spermatid head-demonstrable on glutaraldehyde-stabilized cells by the binding at pH 1.8 of positively charged colloidal particles of ferric oxide. Mature epididymal spermatozoa exhibit an asymmetry in the patterns of distribution of bound colloid over the dorsal vs. ventral surfaces of the sperm head, as well as regional differences between the tail midpiece and principal piece. Surface distributions of anionic residues and lectin (Con A)-binding sites characteristic of mature Suncus spermatozoa are demonstrable within the testis, unlike the situation in most nannals where distinct modifications of the sperm surface occur during epididymal passage.  相似文献   

18.
Pelage coloration of infants was compiled for 138 species of primates. Three functional hypotheses—alloparental, infant defense, and paternity cloak—for primate natal coats are tested. Neonatal pelage contrasted with adult pelage in over half of the species examined. Subtle or inconspicuous contrast was more common than flamboyant contrast. Natal coats began to change at 5.7 weeks and disappeared by 18.0 weeks postpartum on average. The first body part to lose natal coloration was the head and/or dorsum in the majority of species. Functional analyses provided no support for the only published hypothesis—alloparental—while providing partial support for two new hypotheses—infant defense and paternity cloak. A significant association between testes weight and natal coat contrast supports a link between mating system and infant contrast. This is discussed in terms of infanticide avoidance. Natal coats are proposed to be categorically differentiated into inconspicuous and flamboyant types, not differentiated by a continuous gradation, such as color. Subspecific differentiation and patterns of shared ancestry are assessed. Am J Phys Anthropol 104:47–70, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

19.
Human umbilical tissue-derived cells (hUTC) represent an attractive cell source and a potential technology for neurorestoration and improvement of functional outcomes following stroke. Male Wistar rats were subjected to a transient middle cerebral artery occlusion (tMCAo) and were intravenously administered hUTC (N = 11) or vehicle (N = 10) 48 hrs after stroke. White matter and vascular reorganization was monitored over a 12-week period using MRI and histopathology. MRI results were correlated with neurological functional and histology outcomes to demonstrate that MRI can be a useful tool to measure structural recovery after stroke. MRI revealed a significant reduction in the ventricular volume expansion and improvement in cerebral blood flow (CBF) in the hUTC treated group compared to vehicle treated group. Treatment with hUTC resulted in histological and functional improvements as evidenced by enhanced expression of vWF and synaptophysin, and improved outcomes on behavioral tests. Significant correlations were detected between MRI ventricular volumes and histological lesion volume as well as number of apoptotic cells. A positive correlation was also observed between MRI CBF or cerebral blood volume (CBV) and histological synaptic density. Neurological functional tests were also significantly correlated with MRI ventricular volume and CBV. Our data demonstrated that MRI measurements can detect the effect of hUTC therapy on the brain reorganization and exhibited positive correlation with histological measurements of brain structural changes and functional behavioral tests after stroke. MRI ventricular volumes provided the most sensitive index in monitoring brain remodeling and treatment effects and highly correlated with histological and functional measurements.  相似文献   

20.
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