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51.
Various methods have been published in the literature to estimate endocranial capacity. These are based on mathematical equations using measurements made directly on the skull or indirectly from X-rays, by filling the skull with various materials, by endocasts both physical and virtual (using 3D CT-scan reconstructions). Each method has its advantages, limits and drawbacks. A useful method is one that is simple, time-efficient, cheap, and reproducible. For this study we estimated endocranial capacity by filling the skull with calibrated glass beads. We used a thorough protocol of tamping to ensure results reproducibility. Intra- and inter-observer trials showed no significant differences. The method was applied to 130 recent French (West European) skulls (65 males and 65 females). Sexual dimorphism was studied using logistic regression functions, discriminant analysis, and neural network. The best results were obtained using the neural network, built with two hidden nodes in the hidden layer and one output node, and trained with a steepest descent algorithm. Our tests show that there is obvious sexual dimorphism (p < 10(-5)) of the weight of the skulls (623.44 ± 106.83 g in males; 548.07 ± 94.57 in females), the weight of the glass beads used to fill the skulls (2379.83 ± 228.92 g in males; 2095.95 ± 145.49 in females), and endocranial capacity (1676.47 cm(3) ± 161.26 in males; 1476.48 ± 102.49 in females), but overlapping between sexes is quite significant. The average ECC in male (1676.5 cm(3)) and in female (1476.5 cm(3)) subjects is higher than those previously published, which deserves some discussion.  相似文献   
52.
The performance of two spray reagents, iodine-benzoflavone and ruthenium tetroxide (RTX), was evaluated and compared with the conventional technique currently used at the crime scene, that is, powdering. Neither the spray techniques nor powdering were shown to be suitable for all surfaces and ages of marks tested. On some surfaces such as glass and treated wood, powdering was still the superior technique, whereas the spray techniques produced better development on wallpaper, vinyl, and brick. Sequencing work showed that RTX was incompatible with powdering and cyanoacrylate (with a rhodamine 6G stain). Iodine-benzoflavone can be used successfully either before or after powdering in a sequence; however, it was incompatible with cyanoacrylate. Two non-CFC formulations of iodine-benzoflavone using HFC4310mee and HFE7100 solvents were tested and shown not to be as effective as the original Arklone (CFC-113) formulation; however, the HFC4310mee solvent is recommended as the most suitable replacement solvent. Due to the expense of the commercial RTX spray, attempts at formulating a more cost-effective version were also carried out. A formulation was developed that gave comparable development to the commercial version but at a much cheaper cost, and with a shelf life of up to two months. Recommendations are presented for which techniques are suitable for different surfaces and ages of marks. Powdering was shown to be the best technique on all ages of marks tested on treated wood, glass, and also on marks aged three days and older on paint. Iodine-benzoflavone was the best technique on wallpaper, vinyl, brick, and raw wood. RTX was the best detection technique for fresh marks and marks aged up to one day on wallpaper and paint.  相似文献   
53.
本文把由"城中村"转制而形成的社区定义为"城中村"社区.在"城中村"社区内部存在的街道、居委会、以及经济联社三大治理主体,在参与社区治理的过程中形成了一个以各自利益为结点的网络.本文以广州市白云区柯子岭村为个案,描述三元治理主体在社区中的现状,阐释其历史渊源,为处于转制过渡时期的"城中村"社区提供政策参考.  相似文献   
54.
目的 研究白芍配方颗粒生产过程中白芍质量标志物的量值传递规律,优化其制备工艺。方法 通过白芍质量标志物6个成分含量及转移率,分析白芍饮片-提取液-浓缩液-干膏粉-配方颗粒中的量值传递关系,寻找生产过程中关键影响因素;并以出膏率、质量标志物的含量为考察指标,结合信息熵赋权法优化工艺关键参数。结果 浓缩和制粒两个过程中,6种成分含量略下降,但无显著性差异(P>0.05),且转移率相对较高;提取过程中,氧化芍药苷、芍药内酯苷、芍药苷、没食子酰芍药苷、苯甲酰芍药苷等5种成分含量分别下降44.00%、24.74%、27.50%、19.57%、37.25%,其中芍药苷、没食子酰芍药苷、苯甲酰芍药苷等3种成分含量有显著性差异(P<0.05),且氧化芍药苷的平均转移率为51.98%,相对较低;干燥过程中,6种成分含量均有降低趋势,其中芍药内酯苷、芍药苷、没食子酰芍药苷、苯甲酰芍药苷等4种成分的转移率分别降低10.79%、11.29%、15.45%、10.95%,均有显著性差异(P<0.05);提示关键过程为提取和干燥过程,进一步确定关键影响因素为提取时间和干燥温度。通过优化,确定最佳工艺为“白芍饮片加10倍量水,浸泡30 min后,煎煮40 min,再加8倍量水,煎煮40 min;70℃减压浓缩至相对密度为1. 07~1. 09 g/mL,以进风温度为140℃进行喷雾干燥;加适量糊精,混合均匀,干法制粒”。经过优化,芍药内酯苷、芍药苷、没食子酰芍药苷、苯甲酰芍药苷等转移率在提取过程中分别增加16.73%、9.50%、12.92%、7.48%,均有显著性差异(P<0.01),在干燥过程中分别增加15.68%、11.80%、11.69%、10.42%,均有显著性差异(P<0.01)。结论 优化的工艺稳定、重复性好,白芍质量标志物中6种成分很大程度上得到保留,白芍配方颗粒的整体质量得到提升,为之后的生产和质量控制提供科学参考。  相似文献   
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