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1.
2.
The Gilbert-McKern method for aging the female Os pubis has attained popularity following Gilbert's ('73) demonstration that the McKern-Stewart male standards are not directly applicable to females. In order to assess the reliability of the method, forensic anthropologists were asked to age a set of 11 pubes of known age. There was a great deal of variability in the responses of the 23 participants. Three, four, and five different responses (out of a 6-scale system) were given for each component of each pubic bone. Only 51% of the assessments yielded age ranges which would include the known age of the specimens. Analysis of the errors showed that one of the focal problems of the Gilbert-McKern system was the difficulty in judging whether the ventral rampart was building up or breaking down.  相似文献   

3.
A method for aging the female Os pubis   总被引:1,自引:0,他引:1  
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4.
A well-documented multiracial sample of 704 male pubic bones allows for rigorous testing for racial differences in pubic symphyseal metamorphosis. The relationship between estimated age (using a modified Todd six-stage system) and age is examined as a function of race (White, Black, Mexican). One set of analyses incorporates linear regression models, while a second set does not impose such structure on the relationship. The latter analyses incorporate analysis of variance and related procedures. Significant differences in age are found across racial groups; it is seen that Blacks and Mexicans with advanced pubic symphyseal patterns tend to have lower ages than Whites. We do not address the question of causality, which may involve genetic factors and/or environmental variables such as diet, alcoholism, or drug abuse.  相似文献   

5.
Genome engineering using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated nucleases, such as Cas9 (CRISPR-associated protein 9), are revolutionising molecular biology. In this study, we established a Cas9-based genome editing system in Fusarium graminearum, a highly destructive fungal pathogen of cereal crops. Although the molecular toolkit of F. graminearum is well developed compared to other fungi, Cas9-mediated engineering offers a number of potential benefits, such as the ability to create marker free mutants in this species. Here we have used a codon-optimised Cas9 nuclease and dual ribozyme-based expression of a single guide RNA (sgRNA) to induce mutations. Cas9-mediated mutations were identified through a fungicide resistance-based phenotypic screen, which selects for null mutations in the FgOs1 gene encoding an osmosensor histidine kinase. In the absence of selection, however, mutations were identified at very low frequency. Examination of the mutant alleles identified suggests that, a microhomology-mediated end joining (MMEJ) DNA repair pathway is likely to be the predominant process involved in erroneous repairing of Cas9-induced double-stranded breaks in F. graminearum.  相似文献   

6.
This study is based upon 48 3-dimensional coordinates taken on 4 fossil hominid and 127 extant hominoid coxal bones. The follis include Sts 14, SK 3155, MLD 7, and MLD 25. The comparative sample consists of 42 Homo sapiens, 27 Pan troglodytes, 29 Gorilla gorilla and 29 Pongo pygmaeus. The coordinates improve the metrical representation of the bone beyond what can be done with linear measurements because the shape complexity of the os coxae is so great. The coordinates are rotated and translated so that all bones are in a standard position. The coordinates are then standardized for each specimen by dividing all coordinates by the pooled standard deviation of X, Y, and Z coordinates. These data are treated to standard statistical analyses including analysis of variance, Penrose size and shape statistics, principal coordinates and components, and canonical variates analysis. The data are then further altered by using some specimen as a standard and rotating each specimen until the total squared distance between its coordinates and those of the standard are minimized. The same statistics are applied to these "best fit" data. The results show a high degree of agreement between the methods. The hominid os coxae are dundamentally different from the other hominoids and the fossil hominids share the basic hominid configuration but with some unique differences.  相似文献   

7.
A fossil human femur of Homo heidelbergensis from the site of the Sima de los Huesos (Atapuerca, Spain) was reconstructed from two main proximal and distal portions and numerous smaller fragments from the diaphysis. The use of an evaporative process to separate the bone fragments during their restoration represents an innovative approach in restoring paleontological materials and the intervention has resulted in the reconstruction of a complete femur. To avoid excessive manipulation of the reconstructed femur, a mold (negative) and cast (positive) were made of the restored specimen. This case study provides general protocols which can be widely applied to the restoration of paleontological materials from the moment of their excavation until they are deposited in a research center.  相似文献   

8.
Age determination of the male os pubis   总被引:1,自引:0,他引:1  
An extensive (n = 739) sample of well-documented male pubic bones was examined for age-related features. Using the traditional aging methods, Todd's system was found to over-age and both the Todd and the McKern-Stewart systems did not account for age variability seen in advanced pubic bone patterns. Based on a 5-year interobserver error study, certain categories in each system were collapsed because observers could not consistently differentiate between them by morphological pattern. The traditional and the modified versions were than analyzed using linear regression analysis. All approaches perform poorly when the entire sample is used. Truncation strategies to eliminate older individuals result in substantial improvement. The traditional Todd system and its modified form are found to be the best systems. When implementation is considered, a modified Todd six-phase system is recommended.  相似文献   

9.
In 6 of 17 skulls of Indri indri retaining distinct sutures in the medial orbital wall, a small separate bony element intervenes between the frontal and the maxillolacrimal suture. This element is demonstrably continuous with the ethmoid on one such skull. The occurrence of an ethmoid exposure in the orbit of Indri suggests that this trait is not a simple function of orbital size and convergence. Since such an exposure is found in non-cheirogaleine lemuriforms, its distribution provides no support for the hyothesis that lorises and galagos are derived from cheirogaleines.  相似文献   

10.
Calcaneus secundarius: description and frequency in six skeletal samples   总被引:1,自引:0,他引:1  
The calcaneus secundarius (CS) is a small accessory ossicle of the anterior calcaneal facet. A sample of 1,367 calcanei including early 20th century U.S. blacks and whites, XIIth Dynasty Egyptians, Islamic Period Bahrainis, and protohistoric American Indians from two states were examined to determine the frequency of this nonmetric trait. Statistical testing of the correlation of the trait with sex could only be performed on the blacks and whites, a documented cadaver collection. Tests of chi 2 indicated that, although sex differences were insignificant, significant group (not necessarily racial or geographical) differences existed at the .05 level. There was no correlation of side dominance in the overall sample, although significant population differences existed. The trait frequencies of the black and white samples were more similar to one another than to the nonindustrial groups who, in turn, were more similar to each other than to the Terry sample. The findings suggest that a CS is of genetic or congenital origin resulting in a secondary center of ossification in the anterior calcaneal facet.  相似文献   

11.
Innominate bones from 362 California Indians were sexed with Phenice's three non-metrical features of the os pubis. The frequencies of marked, intermediate, and absent cases of these three morphological features were tabulated in males and females to see if unambiguous and reliable distinctions were consistently available. The results suggest that Phenice's technique offered extremely reliable sex evaluations in this material.  相似文献   

12.
本文报道了浙南地区两个淡水蓝藻新种,它们分别命名为溪生翅线藻Petalonema fluminalis sp.nov.,尖形颤藻Oscillatoria rhaphis sp.nov. 1.溪生翅线藻新种Petalonema fluminalis Zhao sp.novv.(图1)。植物体常与胶须藻属Rivularia藻类混生,暗紫色,丝体不规则弯曲,宽40—80μm,长3—9mm;丝体和个体细胞胶质鞘明显,很厚,无同心收缢,黄或黄褐色,丝体鞘11—29μm,分两层,外层明显呈漏斗状,内层分层,平行于藻丝,个体细胞鞘4—11μm,不分  相似文献   

13.
本文研究了以中国汉族男性航骨推断身高的方法.研究样本来自公安部第二研究所法医室近年收集的248对已知确切身高的汉族成年男性完整干燥防骨.依据人体测量学方法,共测量了12项指标.相关分析表明,所测指标与身高的相关系数的统计学检验均有非常显著的意义.进而建立了航骨推断身高的直线回归方程及多元回归方程.并用30对国人脱骨对各方程进行了盲测.结果表明,助骨推算身高的直线回归方程与多元日归方程所得结果与实际身高相近.效果较好.并且田骨推算身高的一元回归方程与多元回归方程的实用价值基本相同.  相似文献   

14.
The kinetics of oxidation of sunset yellow (SY) by sodium-N-chloro-p-toluenesulfonamide or chloramine-T (CAT) was studied spectrophotometrically in HClO4 and NaOH media with Os(VIII) as a catalyst in the latter medium at 298 K and 303 K, respectively. In acid medium, the experimental rate law is −d[CAT]/dt = k[CAT]0[SY]0[HClO4]−0.46. Alkali accelerates the rate of reaction and the rate law takes the form −d[CAT]/dt = k[CAT]0[SY]0[NaOH]0.23[OsO4]0.84. The solvent isotope effect was studied using D2O. Benzenesulfonic acid and 1,2-naphthoquinone-6-sulfonic acid were characterized as the oxidation products of SY. Under identical set of experimental conditions in alkaline medium, Os(VIII) catalyzed reaction is about seven-fold faster than the uncatalyzed reaction. Activation parameters for the overall reaction and also with respect to catalyst have been evaluated. The observed results have been explained by plausible mechanisms and the related rate laws have been deduced.  相似文献   

15.
Pubic bones from 486 modern American females between the ages of 13 and 99 were studied in an attempt to explore the relationship between the degree of dorsal pitting and the following variables: (1) number of full term pregnancies, (2) inteval since last pregnancy, (3) age of decedent.A statistical association was found between the number of full term pregnancies and the degree of dorsal pitting. However, the correlation is not strong; 17 females reported as being nulliparous have "medium to large" dorsal changes whereas 22 females having from one to five full term pregnancies have an absence of dorsal changes. Females who had their last child 15 or more years prior to death are more apt to have "medium to large" dorsal changes than are females who have more recently given birth. This effect appears to be independent of the number of full term pregnancies, but is probably related to age. When the data are analyzed by multiple regression analaysis, it is found that age and number of pregnancies are most important in predicting the degree of pitting and the effect of the interval on pitting is not significant. Age is found to be an important variable independent of the number of full term pregnancies. In nulliparas, an absence of dorsal pitting is far more frequently found in females younger than 30 than in those over 30.  相似文献   

16.
Measuring the amounts of nitrogen and carbon in small quantities of ancient bones before radiocarbon dating using elemental analysis is a way to quantify the amount of preserved collagen and the quantity of exogenous contaminating carbon. Such a measurement can be performed on a large number of samples and allows to sort out the specimens with the best preserved collagen, those with the most carbon contamination, and eventually to infer relationships between burial conditions and collagen preservation. This approach is most interesting as a preliminary method to use before attempting radiocarbon dating using accelerator mass spectrometry of bone collagen.  相似文献   

17.
We examined the morphology of the wrist (carpal region) skeleton using histological serial sections and cleared and stained forelimbs of representatives of three rodent clades: ‘Hystricomorpha’ (Caviomorpha: Ctenomys opimus, C. talarum, Cuniculus taczanowskii, Erethizon dorsatum, Galea sp., Lagostomus maximus, Spalacopus cyanus; Phiomorpha: Fukomys mechowii, Heliophobius argenteocinereus, Hystrix cristata, H. africaeaustralis; Ctenodactylids (Ctenodactylus gundi)), ‘Myomorpha’ (Arvicola amphibius, Ondatra zibethicus, Meriones unguiculatus, Myodes glareolus, Spalax sp.) and ‘Sciuromorpha’ (Eliomys quercinus, Glis glis, Marmota marmota). We describe the arrangement of the carpal bones and identify several variable traits, some of which represent convergent evolution. One element, the Os posthamatum, lies in the carpal region and has not been recorded before. We interpret this bone as a putative autapomorphy of Hystricognathi but not of ‘Hystricomorpha’.  相似文献   

18.
着-COP蛋白是真核生物分泌途径中COP玉有被小泡的一个亚基。本研究利用PCR技术扩增水稻着-c op基因(Os着-c op 1)的ORF(开放阅读框),并克隆到原核表达载体pET-23d上,将表达载体pET-Os着-cop1转入大肠杆菌BL21(DE3),以1.0 mmol/L的IPTG (isopropylβ-D-thiogalactoside)诱导表达重组蛋白,然后以重组蛋白作为抗原免疫家兔,制备多克隆抗体。SDS-PAGE电泳分析结果表明,成功诱导表达了分子量约为35 kD的重组蛋白,Western blot检测表明,免疫家兔的抗血清与水稻幼穗总蛋白杂交信号较好。Os着-COP1抗体的制备有助于研究该基因及COPI小泡在水稻中的功能。  相似文献   

19.
Lu F  Li G  Cui X  Liu C  Wang XJ  Cao X 《植物学报(英文版)》2008,50(7):886-896
Histone methylation homeostasis is achieved by controlling the balance between methylation and demethylation to maintain chromatin function and developmental regulation. In animals, a conserved Jumonji C (JmjC) domain was found In a large group of histone demethylases. However, it is still unclear whether plants also contain the JmjC domaincontaining active histone demethylases. Here we performed genome-wide screen and phylogenetic analysis of JmjC domaincontaining proteins in the dicot plant, Arabidopsis, and monocot plant rice, and found 21 and 20 JmjC domain-containing, respectively. We also examined the expression of JmjC domain-containing proteins and compared them to human JmjC counterparts for potential enzymatic activity. The spatial expression patterns of the Arabidopsis JmjC domaincontaining genes revealed that they are all actively transcribed genes. These active plant JmjC domain-containing genes could possibly function in epigenetic regulation to antagonize the activity of the large number of putative SET domaincontaining histone methyltransferase activity to dynamically regulate histone methylation homeostasis.  相似文献   

20.
作者对近年在华南地区收集的70具成年男性完整骸骨的颅围、锁骨最大长、肩胛骨形态宽及髋骨最大长进行了测量。相关分析表明,各测量项目与身高的相关系数均有非常显著的意义(p<0.01)。进而建立了相应的回归方程。用70例已知生前身高的国人骸骨对这些回归方程进行了检验。结果表明,本文所建立的这些回归方程均有一定的实用价值。  相似文献   

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