Three-dimensional modeling of the various volumes of canines to determine age and sex: a preliminary study

Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.     

山东省机械企业一线职工收入分配状况的调查分析与对策建议

经调查,2007-2009年近三年来,山东省机械企业一线职工的工资收入增长缓慢,收入水平偏低,职工收入分配差距不断扩大,职工对企业工资决定机制参与度低,职工对收入分配不公平反映强烈。分析造成这种状况的原因,主要是有关法律法规不完善、政府宏观调控乏力、企业内部工资决定机制设置不合理、工会组织发挥作用不够等。改进的对策和建议是：加快修订和完善企业工资分配等方面的法律、法规;强化政府宏观调控的措施和手段;指导企业建立公平合理的工资分配机制;充分发挥工会组织在调节企业收入分配中不可代替的作用。     

Age estimation by pulp/tooth ratio in canines by peri-apical X-rays

Estimation of age in individuals has received considerable attention in forensic science, in which it is a widely used method for individual identification, together with paleo-demographic analyses to establish mortality patterns in past populations. The present investigation, which is a continuation of a previously published pilot study, was conducted to examine the possible application of the pulp/tooth area ratio by peri-apical images as an indicator of age at death. A total of 200 peri-apical X-rays of upper and lower canines were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. They belong to the Frassetto osteological collection of Sassari (Sardinia) and are housed in the Museum of Anthropology, Department of Experimental and Evolutionistic Biology, University of Bologna. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio on upper (x(1)) and lower (x(2)) canines. Very good agreement was found between intraobserver measurements. Statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation, with chronological age as dependent variable, and gender, and upper and lower canines as independent variables. Stepwise regression analysis showed that gender did not contribute significantly to the fit (p=0.881) whereas variables x(1) and x(2) and the first-order interaction between them did. These two variables explained 92.5% of variations in estimated chronological age and the residual standard error was 4.06 years. Lastly, two simple linear regression equations were obtained for age estimation using canines from the maxilla and mandible separately. Both models explained 86% of variations in estimated chronological age and allowed an age-at-death estimate with a residual standard error of about 5.4 years.     

Measuring the intercondylar shelf angle using radiographs: intra- and inter-observer error tests of reliability

This study presents a test of intra- and inter-observer measurement error rates of the intercondylar shelf angle of the distal femur, as measured on lateral radiographs. This measurement is the central element of a method to determine racial affiliation from the distal femur. Four observers independently radiographed a set of 33 complete and partial femora from collections housed at the Joint POW/MIA Accounting Command, Central Identification Laboratory. Each observer then measured the intercondylar shelf angles in each radiograph, following the original method's guidelines. A supplementary inter-observer error test was conducted by four additional observers on one set of radiographs. Statistically significant differences were found for both intra- and inter-observer error based on the results of Student's t-tests, paired samples t-tests, and ANOVA analyses. The results of this study indicate that further experimentation should be undertaken in order to develop refined measurement techniques that may help improve standardization and reduce the observer error rates.     

Age estimation by pulp/tooth ratio in canines by mesial and vestibular peri-apical X-rays

Changes in the size of the pulp canal, caused by apposition of secondary dentine, are the best morphometric parameters for estimating age by X-rays. The apposition of secondary dentine is the most frequently used method for age estimation in adult subjects. In two previous papers, we studied the application of the pulp/tooth area ratio by peri-apical X-rays as an indicator of age at death. The aim of the present study was to test the accuracy of age evaluation by combined analysis of labio-lingual and mesial peri-apical X-rays of lower and upper canines. A total of 200 such X-rays were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio according to labio-lingual and mesial X-rays on upper (x(1), x(2)) and lower (x(3), x(4)) canines. Very good agreement was found between intra-observer measurements. Statistical analysis showed that all variables x(1), x(2), x(3), and x(4) and the first-order interaction between x(1) and x(3) contributed significantly to the fit, so that they were included in the regression model, yielding the following regression formula: Age = 120.737 - 337.112x(1) - 79.709x(2) - 364.534x(3) - 65.655x(4) + 1531.918x(1)x(3) . The residual standard error of estimated ages was 3.62 years, with 94 degrees of freedom, and the median of the residuals was -0.155 years, with an interquartile range of 4.96 years. The accuracy of the method was ME = 2.8 years, where ME is the mean prediction error. The model also explained 94% of total variance (R(2) = 0.94).     

Ossification Degrees of Cranial Sutures Determined with Flat‐Panel Computed Tomography: Narrowing the Age Estimate with Extrema

Abstract: Since Broca’s time (1824–1880), ossification of the neurocranial sutures has been used as a characteristic of age. Current approaches include the visual macroscopic examination of ecto and endocranial sutures. The evaluation of the cross‐section of sutures usually necessitates the destruction of the neurocranium. In a nondestructive alternative approach that was tested within the context of the “Digital Forensic Osteology” project that ran in cooperation with the Virtopsy^®‐Project, it emerged that the resolution of conventional multi‐slice computed tomography data sets was not high enough to image sutures. Thus for the experiments presented here, the eXplore Locus Ultra flat‐panel computed tomography scanner from GE Healthcare was used. Calottes were scanned during autopsy and then immediately returned to the corpse. So far, the skullcaps of 221 individuals have been scanned. The cross‐sections of 14 suture segments could be assessed for seven previously defined stages of ossification. In a converse step, the 14 highest and lowest age estimate values corresponding to the individual stages of suture closure found were estimated for each calotte. The obtained ranges narrowing down the age estimate were evaluated with statistics. A mean value of 43.31 years for the range of narrowed age estimates shows that this method can be a useful aid in estimating age. The results of intra‐ and inter‐observer tests showed good overall agreement between the findings of three observers. This method is suitable for a nondestructive age estimation and can be used for the entire calotte.     

Testing Discriminant Functions for Sex Determination from Deciduous Teeth*,†

Abstract: Three studies have proposed discriminant functions for sex determination from deciduous tooth crown dimensions, and this study tests the existing functions on a sample of 46 Portuguese immature skeletons of known sex, aged from birth to 10 years. Deciduous teeth were measured in their mesiodistal and faciolingual crown dimensions, and percentage of correct allocation accuracy in determining sex using each specific function was determined. Discriminant functions were also calculated from data collected for this study and tested using cross‐validation. Results show poor overall accuracy (33.3–75%) and poor cross‐validation (46.2–60.0%). This is related to low sexual dimorphism in deciduous tooth crown size, as well as differences in degree of sexual dimorphism and in overall tooth size between different samples. For these reasons, deciduous crown size does not seem to show significant forensic value as discriminator of sex, particularly when methods developed on one population are applied to individuals of another population.     

论高管“问题薪酬”的董事问责

如遇高管薪酬,董事就可能基于互惠和群体思维等情景以及单纯接触效应和框定效应下的生物本能,无意识地"董董相护",高管"寻租"如愿以偿,自应对董事问责。理性回路下的注意路径不能对情感回路下的"董董相护"对症下药,实际上放纵了高管"问题薪酬"。以诚信路径予以涵摄,则可以不枉不纵。是否构成"董董相护",需借助于高管薪酬的合理性进行推论。基于高管薪酬合理性边界的模糊性,拿捏高管薪酬的合理性,需以企业价值最大化为指针,借助高管薪酬的标准、水平和结构的合理性,厘定相应的参照系。     

氟乙酰胺代谢产物氟离子检测芯片的研究

目的研制含氟毒物的检测芯片,实现氟乙酰胺等含氟毒物的快速电化学检测。方法利用氟离子选择电极制备含氟毒物的检测芯片,对芯片各项性能进行测试;建立氟乙酰胺染毒动物模型,使用制备的氟离子芯片检测染毒致死大白兔体内氟离子浓度。结果血液添加标准检测氟离子其线性响应范围为1～10-6mol/L,相关系数为0.9994,平均斜率接近理论斜率,检测限为5×10-7mol/L。染毒组大耳白兔血中氟离子含量较对照组高5～6倍（P〈0.01）,肝、肾、脑组织中氟离子含量较对照组高2～4倍（P〈0.01）。结论此含氟毒物的检测芯片检测氟离子快速、简便、灵敏,可应用于氟乙酰胺等含氟毒物中毒案件的初筛。     

试论渎职犯罪中直接经济损失与间接经济损失的司法认定

渎职犯罪的多个罪名中直接经济损失、间接经济损失直接影响法律责任的认定,因此经济损失的认定成为检察机关反渎职侵权部门应用《立案标准》、查办案件过程中必须予以先期解决的问题。本文拟对实务中涉及的几个问题进行探讨、梳理,以期助益于工作。