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1.
采用基于标志点的几何形态学测量方法对青海循化撒拉族自治县的撒拉族男性82人侧面轮廓形状进行了分析。撒拉族人群额部的变异主要体现在第7、8特征点区域(鼻凹点之上区域),额部其他区域的形态变异较小,而鼻区、嘴唇及下巴区域的形态变异较大,这些特征与土族较相似。同时,撒拉族也显示出明显区别于土族、藏族的形态。如撒拉族额部比较突出,显得前倾,额部相对较长,唇部相对土族较回缩。撒拉族额部特征点集的面积较大,可能反映了撒拉族额部的变异大于土族、藏族。聚类分析显示,男性两类侧面轮廓的差异主要集中在额部,与土族的类别间差异有相似之处。异速生长分析显示,尺寸大小能够解释形状变异的5.51%,随着CS值的增大,额部和下巴部变化明显,额度由陡直趋向于变得平缓,下巴部也随CS值的增大由较突出变为明显回缩。土族、藏族也是随着CS值的增大,额部由陡直趋向于变得平缓,下巴部由较突出变为明显回缩,似乎提示撒拉族、土族、藏族有相似的面部形态变化规律:长面型者的额部较低平,下巴部较回缩。  相似文献   

2.
Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximum likelihood (GREML), we related this global genetic variance to that in the brain response to facial expressions, as assessed with functional magnetic resonance imaging (fMRI) in a community-based sample of adolescents (n = 1,620). Brain response to facial expressions was measured in 25 regions constituting a face network, as defined previously. In 9 out of these 25 regions, common genetic variance explained a significant proportion of phenotypic variance (40–50%) in their response to ambiguous facial expressions; this was not the case for angry facial expressions. Across the network, the strength of the genotype-phenotype relationship varied as a function of the inter-individual variability in the number of functional connections possessed by a given region (R2 = 0.38, p<0.001). Furthermore, this variability showed an inverted U relationship with both the number of observed connections (R2 = 0.48, p<0.001) and the magnitude of brain response (R2 = 0.32, p<0.001). Thus, a significant proportion of the brain response to facial expressions is predicted by common genetic variance in a subset of regions constituting the face network. These regions show the highest inter-individual variability in the number of connections with other network nodes, suggesting that the genetic model captures variations across the adolescent brains in co-opting these regions into the face network.  相似文献   

3.
软组织厚度作为颅骨面貌复原的基础, 具有重要的应用价值。本文借助计算机技术对西安地区132例成年人颅面数据样本开展软组织测量、分析及应用研究, 结果表明, 1)通过分析特征点处软组织厚度和面部软组织分布图, 发现面部软组织分布具有一定的规律, 额头区域软组织厚度薄且样本间差异小, 脸颊区域软组织厚且样本间差异大; 2)通过比较不同年龄段男性软组织厚度的均值, 发现20-30岁阶段软组织厚度均值最小, 50-60岁阶段软组织厚度均值其次, 30-40岁阶段软组织厚度均值最大, 但30-40岁和40-50岁两个年龄段的软组织厚度近似; 通过比较不同年龄段女性软组织厚度的均值, 发现20-30岁阶段软组织厚度均值最小, 30-40岁阶段软组织厚度均值其次, 40-50岁阶段的软组织厚度均值最大; 3)特征点处软组织厚度标准差可以反映面貌体态的差异, 因此根据10个脸颊特征点的软组织厚度均值和标准差实现面貌体态分类; 4)根据不同性别、年龄、体态对应的软组织平均厚度, 应用计算机技术实现给定颅骨的三维面貌复原, 复原结果相比于传统手工复原的结果更加科学。  相似文献   

4.
In studies of social inference and human mate preference, a wide but inconsistent array of tools for computing facial masculinity has been devised. Several of these approaches implicitly assumed that the individual expression of sexually dimorphic shape features, which we refer to as maleness, resembles facial shape features perceived as masculine. We outline a morphometric strategy for estimating separately the face shape patterns that underlie perceived masculinity and maleness, and for computing individual scores for these shape patterns. We further show how faces with different degrees of masculinity or maleness can be constructed in a geometric morphometric framework. In an application of these methods to a set of human facial photographs, we found that shape features typically perceived as masculine are wide faces with a wide inter-orbital distance, a wide nose, thin lips, and a large and massive lower face. The individual expressions of this combination of shape features—the masculinity shape scores—were the best predictor of rated masculinity among the compared methods (r = 0.5). The shape features perceived as masculine only partly resembled the average face shape difference between males and females (sexual dimorphism). Discriminant functions and Procrustes distances to the female mean shape were poor predictors of perceived masculinity.  相似文献   

5.
Down syndrome (DS), resulting from trisomy of chromosome 21, is the most common live-born human aneuploidy. The phenotypic expression of trisomy 21 produces variable, though characteristic, facial morphology. Although certain facial features have been documented quantitatively and qualitatively as characteristic of DS (e.g., epicanthic folds, macroglossia, and hypertelorism), all of these traits occur in other craniofacial conditions with an underlying genetic cause. We hypothesize that the typical DS face is integrated differently than the face of non-DS siblings, and that the pattern of morphological integration unique to individuals with DS will yield information about underlying developmental associations between facial regions. We statistically compared morphological integration patterns of immature DS faces (N = 53) with those of non-DS siblings (N = 54), aged 6-12 years using 31 distances estimated from 3D coordinate data representing 17 anthropometric landmarks recorded on 3D digital photographic images. Facial features are affected differentially in DS, as evidenced by statistically significant differences in integration both within and between facial regions. Our results suggest a differential affect of trisomy on facial prominences during craniofacial development.  相似文献   

6.
Human facial morphology is a combination of many complex traits. Little is known about the genetic basis of common facial morphological variation. Existing association studies have largely used simple landmark-distances as surrogates for the complex morphological phenotypes of the face. However, this can result in decreased statistical power and unclear inference of shape changes. In this study, we applied a new image registration approach that automatically identified the salient landmarks and aligned the sample faces using high density pixel points. Based on this high density registration, three different phenotype data schemes were used to test the association between the common facial morphological variation and 10 candidate SNPs, and their performances were compared. The first scheme used traditional landmark-distances; the second relied on the geometric analysis of 15 landmarks and the third used geometric analysis of a dense registration of ∼30,000 3D points. We found that the two geometric approaches were highly consistent in their detection of morphological changes. The geometric method using dense registration further demonstrated superiority in the fine inference of shape changes and 3D face modeling. Several candidate SNPs showed potential associations with different facial features. In particular, one SNP, a known risk factor of non-syndromic cleft lips/palates, rs642961 in the IRF6 gene, was validated to strongly predict normal lip shape variation in female Han Chinese. This study further demonstrated that dense face registration may substantially improve the detection and characterization of genetic association in common facial variation.  相似文献   

7.
We report a novel X-linked mental retardation (XLMR) syndrome, with characteristic facial dysmorphic features, segregating in a large North Carolina family. Only males are affected, over four generations. Clinical findings in the seven living affected males include a moderate degree of mental retardation (MR), coarse facies, puffy eyelids, narrow palpebral fissures, prominent supraorbital ridges, a bulbous nose, a prominent lower lip, large ears, obesity, and large testicles. Cephalometric measurements suggest that the affected males have a distinctive craniofacial skeletal structure, when compared with normative measures. Obligate-carrier females are unaffected with MR, but the results of cephalometric skeletal analysis suggest craniofacial dysmorphisms intermediate between affected males and normative control individuals. Unaffected male relatives show no clinical or cephalometric resemblance to affected males. The blood-lymphocyte karyotype and the results of DNA analysis for fragile-X syndrome and of other routine investigations are normal. Linkage analysis for polymorphic DNA markers spanning the X chromosome established linkage to Xq26-q27. Maximum LOD scores were obtained at marker DXS1047 (maximum LOD score = 3.1 at recombination fraction 0). By use of haplotype analysis, we have localized the gene for this condition to an 18-cM genetic interval flanked by ATA59C05 and GATA31E08. On the basis of both the clinical phenotype and the mapping data, we were able to exclude other reported XLMR conditions. Therefore, we believe that a unique recessive XLMR syndrome with a distinctive and recognizable phenotype is represented in this family.  相似文献   

8.
目前,中国人群头型、面型、鼻型、唇型、耳型尚未见大样本的资料报道。我们测量了中国115个族群的63449例头面部指标值,计算了头长宽指数等7项指数值,进行了指数与年龄的相关分析、年龄组间的方差分析,以及指数与纬度、年平均温度的相关分析。采用主成分分析方法研究了7个年龄组指数值。相关分析显示,随着年龄增长,中国人头型变得更长一些,更低一些;面变得更窄一些,鼻翼更宽一些,唇更薄些,耳变得更细长些。主成分分析结果也证实了这种规律。相关分析结果表明,随纬度的增大,中国人男性、女性头长宽指数、形态面指数值增大,鼻指数、容貌耳指数值减小。随年平均温度的升高,中国人男性、女性头面部头长宽指数、头长高指数、形态面指数值减小,鼻指数、容貌耳指数值增大。中国人头长宽指数的圆头型率、中头型率较高。男性、女性头长高指数均以高头型为主,头宽高指数均以狭头型率最高,形态面指数以超狭面型率最高。超过一半的人鼻指数为中鼻型,其次为狭鼻型。  相似文献   

9.
10.
Hypohidrotic ectodermal dysplasia (HED) is characterized by clinical manifestations of severe hypodontia or anodontia, hypotrichosis, hypohidrosis, and specific facial appearance. Affected males show complete expression of clinical features of this condition. Their mothers, who are gene carriers, express only some signs, which are usually very mild. Currently available clinical methods are not sufficient for routine identification of the HED heterozygous gene carriers. The purpose of this study was to identify and describe the facial characteristics of HED patients and their mothers and to evaluate the usefulness of craniofacial pattern profile analysis (CFPP) in the diagnosis of this syndrome and the detection of gene carriers. In this study six affected males and their mothers were evaluated. Z-scores for each variable were calculated and compared with age- and sex-matched controls. Anthropometric analysis showed a specific dysmorphic pattern in CST patients that includes decreased skull base width (t-t: -1.67 Z); decreased forehead width (ft-ft: -1.8 Z), decreased midface depth (sn-t: -2.02 Z), markedly decreased total facial height (n-gn: -3.4 Z), and markedly decreased maxillary arc (t-sn-t: -2.5 Z). Gene carriers showed a similar tendency in their pattern profiles. They showed the same tendency towards lower Z-values for forehead width, facial height, and mouth width. The values for these measurements were between those of the affected and healthy controls. The most pronounced findings were increased head width (eu-eu: +2.83 Z), increased lower face width (go-go: +2.06 Z), and reduction of total facial height (n-gn: -0.95 Z). They also displayed increased nose width (al-al: +2.41 Z) and increased biocular distance (ex-ex: +2.01 Z). When used in conjunction with other methods the anthropometrics pattern profile analysis can considerably enhance detection of gene carriers for HED and increase objective assessment of the craniofacial region in HED patients.  相似文献   

11.
Craniofacial morphology is highly heritable, but little is known about which genetic variants influence normal facial variation in the general population. We aimed to identify genetic variants associated with normal facial variation in a population-based cohort of 15-year-olds from the Avon Longitudinal Study of Parents and Children. 3D high-resolution images were obtained with two laser scanners, these were merged and aligned, and 22 landmarks were identified and their x, y, and z coordinates used to generate 54 3D distances reflecting facial features. 14 principal components (PCs) were also generated from the landmark locations. We carried out genome-wide association analyses of these distances and PCs in 2,185 adolescents and attempted to replicate any significant associations in a further 1,622 participants. In the discovery analysis no associations were observed with the PCs, but we identified four associations with the distances, and one of these, the association between rs7559271 in PAX3 and the nasion to midendocanthion distance (n-men), was replicated (p = 4 × 10(-7)). In a combined analysis, each G allele of rs7559271 was associated with an increase in n-men distance of 0.39 mm (p = 4 × 10(-16)), explaining 1.3% of the variance. Independent associations were observed in both the z (nasion prominence) and y (nasion height) dimensions (p = 9 × 10(-9) and p = 9 × 10(-10), respectively), suggesting that the locus primarily influences growth in the yz plane. Rare variants in PAX3 are known to cause Waardenburg syndrome, which involves deafness, pigmentary abnormalities, and facial characteristics including a broad nasal bridge. Our findings show that common variants within this gene also influence normal craniofacial development.  相似文献   

12.

Background

Cone-beam Computed Tomography (CBCT) and stereophotography are two of the latest imaging modalities available for three-dimensional (3-D) visualization of craniofacial structures. However, CBCT provides only limited information on surface texture. This can be overcome by combining the bone images derived from CBCT with 3-D photographs. The objectives of this study were 1) to evaluate the feasibility of integrating 3-D Photos and CBCT images 2) to assess degree of error that may occur during the above processes and 3) to identify facial regions that would be most appropriate for 3-D image registration.

Methodology

CBCT scans and stereophotographic images from 29 patients were used for this study. Two 3-D images corresponding to the skin and bone were extracted from the CBCT data. The 3-D photo was superimposed on the CBCT skin image using relatively immobile areas of the face as a reference. 3-D colour maps were used to assess the accuracy of superimposition were distance differences between the CBCT and 3-D photo were recorded as the signed average and the Root Mean Square (RMS) error.

Principal Findings:

The signed average and RMS of the distance differences between the registered surfaces were −0.018 (±0.129) mm and 0.739 (±0.239) mm respectively. The most errors were found in areas surrounding the lips and the eyes, while minimal errors were noted in the forehead, root of the nose and zygoma.

Conclusions

CBCT and 3-D photographic data can be successfully fused with minimal errors. When compared to RMS, the signed average was found to under-represent the registration error. The virtual 3-D composite craniofacial models permit concurrent assessment of bone and soft tissues during diagnosis and treatment planning.  相似文献   

13.
为探讨遗传与环境因素对学龄双生子儿童头面部特征的影响, 对呼和浩特市和包头市7-12岁369对双生子儿童(同卵180对, 同性别异卵141对, 异性别异卵48对)的16项头面部指标进行活体测量。采用通径分析方法, 用Mx软件拟合最佳结构方程模型, 计算各指标遗传与环境方差组分, 分析年龄、性别的作用。结果发现, 校正年龄后, 头部指标中头围的遗传度(男66%, 女66%)较高; 面部指标中, 容貌面高的遗传度(男73%, 女84%)最高, 其次为鼻宽(男57%, 女67%)、眼内角间宽(男57%, 女50%)和额最小宽(男50%, 女50%); 头长(男64%, 女25%)、头宽(男26%, 女82%)、眼外角间宽(男76%, 女34%)和容貌耳长(男23%, 女70%)的遗传度存在一定的性别差异。表明遗传因素与环境因素对学龄双生子儿童的头面部发育均有一定影响, 其中遗传因素对男女头围及容貌面高、男性头长和眼外角间宽、女性头宽、鼻宽、口宽、容貌耳长的影响相对较大。  相似文献   

14.
We examined the lateral cephalograms of Russian patients in the following categories: control with acceptable occlusions (group 1); severe hypodontia with absence of six or more teeth (group 2); and severe hypodontia associated with hypohidrotic ectodermal dysplasia (HED) (group 3). Analysis was in a cross-sectional manner, comparing dimensions at the start of the mixed dentition phase (age 6-10) and in the permanent dentition (age 12-18). The groups were matched for age and sex. Thirty-one hard- and soft-tissue landmarks were traced, and 35 linear, 19 angular, and 7 ratioed measurements were taken and compared, using analysis of variance to compare the means of each group. A reduced anterior face height was found in groups 2 and 3 as a consequence of a reduced anterior lower face height. In group 2 in the mixed dentition, the posterior face height was also reduced. The inclination of the mandible (相似文献   

15.
Various real-time applications such as Human–Computer Interactions, Psychometric analysis, etc. use facial expressions as one of the important parameters. The researchers have used Action Units (AU) of the face as feature points and its deformation is compared with the reference points on the face to estimate the facial expressions. Among many parts of the face, features from the mouth contribute largely to all the well-known emotions. In this paper, the parabola theory is used to identify and mark various points on the lips. These points are considered as feature points to construct feature vectors. The Latus Rectum, Focal Point, Directrix, Vertex, etc. are also considered to identify the feature points of the lower lips and upper lips. The proposed approach is evaluated on benchmark datasets such as JAFFEE and Cohn–Kanade dataset and it is found that the performance is encouraging in understanding the facial expressions. The results are compared with contemporary methods and found that the proposed approach has given good classification accuracy in recognizing facial expressions.  相似文献   

16.
Facial morphology as determined by anthropometry: keeping it simple   总被引:1,自引:0,他引:1  
Anthropometry remains an efficient, noninvasive method for describing craniofacial morphology in spite of the appearance of more sophisticated technologies. The major advantage afforded by anthropometry is its technical simplicity, a fact which makes it a readily available tool for evaluating patients, planning facial surgery, or delineating basic features of craniofacial syndromes. Anthropometry lacks the detail of more powerful technologies, but it is better suited for populational studies because of the availability of comparative, normal databases. The standard z-scores produced by such comparisons lend themselves to multivariate analysis. This type of comparative analysis is not yet possible for computerized tomography, three-dimensional imaging, or photogrammetry. To illustrate the utility of this technique an example is cited from an ongoing study of hypohidrotic ectodermal dysplasia (HED) in which anthropometry reveals details of facial morphology overlooked in previous studies. These include the presence of reduced facial height and a striking reduction in the size of the facial features in spite of the fact that facial widths are comparatively normal. Gene carriers show a similar though nonidentical pattern of defects. Like all morphometric approaches, anthropometry has its limitations. Well-designed protocols minimize these limitations by incorporating multiple facial dimensions in the analysis and by emphasizing careful collection of data with standard instruments and methodology.  相似文献   

17.
Inter-individual variation in facial shape is one of the most noticeable phenotypes in humans, and it is clearly under genetic regulation; however, almost nothing is known about the genetic basis of normal human facial morphology. We therefore conducted a genome-wide association study for facial shape phenotypes in multiple discovery and replication cohorts, considering almost ten thousand individuals of European descent from several countries. Phenotyping of facial shape features was based on landmark data obtained from three-dimensional head magnetic resonance images (MRIs) and two-dimensional portrait images. We identified five independent genetic loci associated with different facial phenotypes, suggesting the involvement of five candidate genes—PRDM16, PAX3, TP63, C5orf50, and COL17A1—in the determination of the human face. Three of them have been implicated previously in vertebrate craniofacial development and disease, and the remaining two genes potentially represent novel players in the molecular networks governing facial development. Our finding at PAX3 influencing the position of the nasion replicates a recent GWAS of facial features. In addition to the reported GWA findings, we established links between common DNA variants previously associated with NSCL/P at 2p21, 8q24, 13q31, and 17q22 and normal facial-shape variations based on a candidate gene approach. Overall our study implies that DNA variants in genes essential for craniofacial development contribute with relatively small effect size to the spectrum of normal variation in human facial morphology. This observation has important consequences for future studies aiming to identify more genes involved in the human facial morphology, as well as for potential applications of DNA prediction of facial shape such as in future forensic applications.  相似文献   

18.
K Guo 《PloS one》2012,7(8):e42585
Using faces representing exaggerated emotional expressions, recent behaviour and eye-tracking studies have suggested a dominant role of individual facial features in transmitting diagnostic cues for decoding facial expressions. Considering that in everyday life we frequently view low-intensity expressive faces in which local facial cues are more ambiguous, we probably need to combine expressive cues from more than one facial feature to reliably decode naturalistic facial affects. In this study we applied a morphing technique to systematically vary intensities of six basic facial expressions of emotion, and employed a self-paced expression categorization task to measure participants' categorization performance and associated gaze patterns. The analysis of pooled data from all expressions showed that increasing expression intensity would improve categorization accuracy, shorten reaction time and reduce number of fixations directed at faces. The proportion of fixations and viewing time directed at internal facial features (eyes, nose and mouth region), however, was not affected by varying levels of intensity. Further comparison between individual facial expressions revealed that although proportional gaze allocation at individual facial features was quantitatively modulated by the viewed expressions, the overall gaze distribution in face viewing was qualitatively similar across different facial expressions and different intensities. It seems that we adopt a holistic viewing strategy to extract expressive cues from all internal facial features in processing of naturalistic facial expressions.  相似文献   

19.
The aim of this methodological anthropometric study was to compare direct anthropometry and digital two-dimensional photogrammetry in 18 male and 27 female subjects, aged 24 to 65 years, from Potsdam, Germany. In view of the rising interest in reliable biometric kephalofacial data, we focussed on head and face measurements. Out of 34 classic facial anatomical landmarks, 27 landmarks were investigated both by direct anthropometry and 2D-photogrammetry; 7 landmarks could not be localized by 2D-photogrammetry. Twenty-six kephalofacial distances were analysed both by direct anthropometry and digital 2D-photogrammetry. Kephalofacial distances are on average 7.6% shorter when obtained by direct anthropometry. The difference between the two techniques is particularly evident in total head height (vertex-gnathion) due to the fact that vertex is usually covered by hair and escapes from photogrammetry. Also the distances photographic sellion-gnathion (1.3 cm, i. e. 11.6%) and nasal-gnathion (1.2 cm, i. e. 9.4%) differ by more than one centimetre. Differences below 0.5 cm between the two techniques were found when measuring mucosa-lip-height (2.2%), gonia (3.0%), glabella-stomion (3.9%), and nose height (glabella-subnasal) (4.0%). Only the estimates of forehead width were significantly narrower when obtained by 2D-photogrammetry (-1.4 cm, -13.1%). The methodological differences increased with increasing magnitude of the kephalometric distance. Apart from these limitations, both techniques are similarly valid and may replace each other.  相似文献   

20.
Attractive facial features in women are assumed to signal fertility, but whether facial attractiveness predicts reproductive success in women is still a matter of debate. We investigated the association between facial attractiveness at young adulthood and reproductive life history—number of children and pregnancies—in women of a rural community. For the analysis of reproductive success, we divided the sample into women who used contraceptives and women who did not. Introducing two-dimensional geometric morphometric methodology, we analysed which specific characteristics in facial shape drive the assessment of attractiveness and covary with lifetime reproductive success. A set of 93 (semi)landmarks was digitized as two-dimensional coordinates in postmenopausal faces. We calculated the degree of fluctuating asymmetry and regressed facial shape on facial attractiveness at youth and reproductive success. Among women who never used hormonal contraceptives, we found attractive women to have more biological offspring than less attractive women. These findings are not affected by sociodemographic variables. Postmenopausal faces corresponding to high reproductive success show more feminine features—facial characteristics previously assumed to be honest cues to fertility. Our findings support the notion that facial attractiveness at the age of mate choice predicts reproductive success and that facial attractiveness is based on facial characteristics, which seem to remain stable until postmenopausal age.  相似文献   

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