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621.
Abstract: The AmpF?STR® Identifiler® Direct PCR Amplification Kit is a new short tandem repeat multiplex assay optimized to allow the direct amplification of single‐source blood and buccal samples on FTA® card without the need for sample purification and quantification. This multiplex assay has been validated according to the FBI/National Standards and SWGDAM guidelines. Validation results revealed that slight variations in primer concentration, master mix component concentration, and thermal cycling parameters did not affect the performance of the chemistry. The assay’s sensitivity was demonstrated by amplifying known amounts of white blood cells spotted onto FTA® cards, and the assay’s specificity was verified by establishing minimal cross‐reactivity with nonhuman DNA. No effect on the age of the sample stored on the FTA® substrate was observed and full concordance was established in the population study. These findings of the validation study support the use of the Identifiler® Direct Kit for forensic standards and database samples genotyping. 相似文献
622.
Quatrehomme G Ponsaillé J Jardin Pd Leccia C Alunni V 《Forensic science international》2011,206(1-3):213.e1-213.e6
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
623.
Astrid Jaime Constanza Pérez-Martelo Bernardo Herrera Gonzalo Ordóñez-Matamoros Dominique Vinck 《政策研究评论》2023,40(2):282-306
We explore the strategies implemented by Research Groups' Leaders while coping with unstable contexts, characterized by incoherence and lack of coordination among different policy discourses and instruments, and scarce resources. We focus on a country where these conditions are present: Colombia. In doing so, we study two cases, one in nanotechnology and another one in biomedical engineering. Interviews, focus groups and workshops allowed us to identify and validate strategies grouped in four popular sayings, proper to local idiosyncrasy, highlighting the role of home institutions and principal investigators in facing such situations with resilience and resourcefulness, and even taking advantage of them. We find that Research Groups' Leaders use strategies such as: adapting, balancing agendas and funding sources, networking, and taking advantage of the support programs available at their home institution to continue functioning. These are setting the ground for a further survey which could pretend some generalization. However, policymakers could consider these findings when defining policy instruments or for assessing their effectiveness or impacts. 相似文献