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Sex estimation by various forensic anthropology approaches is a crucial factor for identification of human skeletal remains. However, inexpensive, uncomplicated and reliable methods are still required, especially in a remote crime scene and a high crime incidence area. Here, we examined 13 sacral parameters from 78 independent skeletons derived from deceases found in Central Thailand (male, n = 46; female, n = 32) using simple standard anthropometric techniques for sex allocation. Discriminant analysis exhibited that anterior-posterior diameter of S1 vertebra corpus (APS) is the most accurate sacral parameter for sex determination in our study with 82.1% of correct discrimination rate. The accuracy could be improved up to 97.4% when additional three sacral variables including the length of sacrum measured from the medial anterior-superior sacral promontory to the medial anterior-inferior S5 vertebra (ASL), alar index (ALI), and the maximum anterior breadth of sacrum measured across sacral alar (ABS) were computed together with APS. These encourage the use of sacral morphometrics for sex assessment of human sacrum remains in Central Thailand. However, further investigation with broadening sacral morphometric data across the country might provide a promising sex determination equation from a sacral skeleton for Thai population.  相似文献   
3.
The primary aim of this study was to evaluate the accuracy of sonographic estimation of fetal weight when performed at due date by first-line sonographers. This was a prospective study including 500 singleton pregnancies. Ultrasound examinations were performed by residents on delivery day. Estimated fetal weights (EFWs) were calculated and compared with the corresponding birth weights. The median absolute difference between EFW and birth weight was 200 g (100–330). This difference was within ±10% in 75.2% of the cases. The median absolute percentage error was 5.53% (2.70%–10.03%). Linear regression analysis revealed a good correlation between EFW and birth weight (r = 0.79, p < 0.0001). According to Bland–Altman analysis, bias was −85.06 g (95% limits of agreement: −663.33 to 494.21). In conclusion, EFWs calculated by residents were as accurate as those calculated by experienced sonographers. Nevertheless, predictive performance remains limited, with a low sensitivity in the diagnosis of macrosomia.  相似文献   
4.
Abstract

This research explores how the level of consumers’ need for cognition (NFC) is associated with celebrity endorser credibility and examines its effects on advertising-related attitudes. A 3 (endorser types: actor/actress, athlete, TV personality/talent) × 2 (endorser’s gender) factorial experiment with 435 Japanese consumers was conducted. Concerning Japanese OTC drug advertising, lower NFC individuals perceived celebrity endorsers as more credible in comparison to higher NFC individuals. The main effects of NFC and endorser type on endorser credibility existed; however, no interaction between the two variables was found. The endorser type had an influence on attitudes toward ads and the advertised brand.  相似文献   
5.
The most widely applied model relating drug concentrations to effects is the Emax model. In practice, concentration–effect relationships often deviate from a simple linear relationship but without reaching a clear maximum because a further increase in concentration might be associated with unacceptable or distorting side effects. The parameters for the Emax model can only be estimated with reasonable precision if the curve shows sign of reaching a maximum, otherwise both EC50 and Emax estimates may be extremely imprecise. This paper provides a solution by introducing a new parameter (S0 ) equal to Emax/EC50 that can be used to characterize potency adequately even if there are no signs of a clear maximum. Simulations are presented to investigate the nature of the new parameter and published examples are used as illustration.  相似文献   
6.
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations.  相似文献   
7.
本文在介绍我院研制成的WKZX型微机自控系统的组成及性能基础上,提出了以微处理机为基础的数字自控系统设计及其规律。介绍了应用本装置所研究的几个实例——PWM微机伺服系统和发酵过程参数预值仿真及其控制等。  相似文献   
8.
In the study of monozygotic twins relative to disease and risk factors, particular interest focuses on the subset who are discordant for some suspected risk factor (for example, smoking), since such twins constitute a natural case-control pair. In such studies, questionnaires designed to identify the status of all twin pairs are sometimes error prone and can yield misleading estimates of the concordance-discordance ratios. Greater efforts to verify the characteristics of apparently discordant pairs than to verify those of apparently concordant pairs can result in the 'unequal ascertainment' fallacy. Using the results of a questionnaire with known error rates and the 'apparent' frequencies yielded, we present unbiased, maximum likelihood estimates of the 'true' proportions of concordant and discordant pairs. concordant and discordant pairs. We also present approximate covariances among these estimates.  相似文献   
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10.
The suicide substrate reaction is a model for certain enzyme-inhibitingdrugs. This reaction system is examined assuming that the substratediffuses freely while the enzyme remains fixed. Two sets ofinitial and boundary conditions are examined: one modellingan instantaneous point source, akin to an injection of substrate,the other, a continuous point source, akin to a continuing influx,or intravenous drip, of substrate. The quasi-steady-state assumptionis applied to obtain analytical solutions for a limited parameterspace. Finally, further applications of numerical and analyticalexperimentation on pharmaceutical mechanisms are described.  相似文献   
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