Analysis of body fluid mixtures by mtDNA sequencing: An inter-laboratory study of the GEP-ISFG working group

The mitochondrial DNA (mtDNA) working group of the GEP-ISFG (Spanish and Portuguese Group of the International Society for Forensic Genetics) carried out an inter-laboratory exercise consisting of the analysis of mtDNA sequencing patterns in mixed stains (saliva/semen and blood/semen). Mixtures were prepared with saliva or blood from a female donor and three different semen dilutions (pure, 1:10 and 1:20) in order to simulate forensic casework. All labs extracted the DNA by preferential lysis and amplified and sequenced the first mtDNA hypervariable region (HVS-I). Autosomal and Y-STR markers were also analysed in order to compare nuclear and mitochondrial results from the same DNA extracts. A mixed stain prepared using semen from a vasectomized individual was also analysed. The results were reasonably consistent among labs for the first fractions but not for the second ones, for which some laboratories reported contamination problems. In the first fractions, both the female and male haplotypes were generally detected in those samples prepared with undiluted semen. In contrast, most of the mixtures prepared with diluted semen only yielded the female haplotype, suggesting that the mtDNA copy number per cell is smaller in semen than in saliva or blood. Although the detection level of the male component decreased in accordance with the degree of semen dilution, it was found that the loss of signal was not consistently uniform throughout each electropherogram. Moreover, differences between mixtures prepared from different donors and different body fluids were also observed. We conclude that the particular characteristics of each mixed stain can deeply influence the interpretation of the mtDNA evidence in forensic mixtures (leading in some cases to false exclusions). In this sense, the implementation of preliminary tests with the aim of identifying the fluids involved in the mixture is an essential tool. In addition, in order to prevent incorrect conclusions in the interpretation of electropherograms we strongly recommend: (i) the use of additional sequencing primers to confirm the sequencing results and (ii) interpreting the results to the light of the phylogenetic perspective.     

Allele frequencies of sixteen STRs in the population of Northern Portugal

Allele frequencies of sixteen autossomal short tandem repeats (STRs), D3S1358, VWA, D16S539, D8S1179, D21S11, D18S51, TH01, FGA, D5S818, D13S317, D7S820, TPOX, CSF1PO, Penta D, Penta E (included in the PowerPlex 16 kit), and the SE33 (PowerPlex ES Monoplex System SE33) were determined in a sample of 200 healthy unrelated individuals from the north of Portugal.     

A qualitative study of compact bone microstructure and nuclear short tandem repeat obtained from femur of human remains found on the ground and exhumed 3 years after death

Forensic identification of human remains is composed of anthropological study of race, sex, age, etc. By using these traditional methods, inconclusive or nonidentified cases could be subjected to DNA analysis. However, in spite of advances in human identification techniques, especially by PCR-amplified DNA, some limitations that affect the ability of obtaining DNA from human remains still persist. Light microscope sections of postmortem compact bones from human remains are presented here for the purpose of increasing a forensic examiner's prediction of successful nuclear DNA typing. Femoral compact bones were obtained from 7 human remains found on the ground, in different degrees of decomposition, and were cleaned by boiling to remove soft tissues, 8 collections of bones having undergone natural decomposition, not boiled (as no soft tissue was adhered), and 5 cadavers 12 to 16 hours postmortem. The histologic sections were stained by hematoxylin and eosin, the loci CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, D16S539, D7S820, D13S317, and amelogenin were amplified by PCR, and the polyacrylamide gel was stained with silver. The results presented here clarify questions concerning the viability of DNA for identification analysis, and they also may help to establish better strategies for optimization of DNA extraction and analysis in compact bones of human remains.     

Application of the Suchey-Brooks method to three-dimensional imaging of the pubic symphysis

Age determination is a major field of interest in forensic anthropology. Among the different methods based on macroscopic skeletal study, the Suchey-Brooks method, which analyzes the pubic symphysis, is one of the most reliable. We applied the Suchey-Brooks method to three-dimensional computed tomographic reconstructions of the pubic symphysis. We demonstrated excellent agreement between the results of analysis of bone samples and those of the three-dimensional images, in particular regarding ridges of the articular surface and delimitation of the extremities. The accuracy of age estimation did not significantly differ (Wilcoxon test) between the Suchey-Brooks method applied to bones and the same method applied to CT images. Using high-quality images, this approach seems as reliable as the standard Suchey-Brooks method and offers several advantages: no bone preparation, no damage to bone material, and the possibility of application to living individuals.     

Climate justice and bargaining coalitions: a discourse analysis

This article adopts a perspective of climate justice as an object of discourse and takes the bargaining coalitions at the Conference of the Parties as the relevant units to map the heterogeneous discourse on climate justice at the Cancun COP16. Based on the statements of nine coalitions, the analysis identifies three discourses on climate justice. The conflict discourse articulates the North–South duality over issues of historical responsibility for climate change. The transition discourse points to solving the problem of sharing the cost of mitigating climate change through a process of global low-carbon growth. The vulnerability discourse focuses on the urgency of ambitious actions by all parties. These three discourses, and their appropriation by the bargaining coalitions, are inherent of new alignments among developed and developing countries alliances and blocs that simultaneously reproduce and surpass the North–South ideological divide.     

Creating markets in no-trust environments: The law and economics of smart contracts

Smart contracts, self-executing agreements based on blockchain technology, have the capacity to create trust in what we term no-trust contracting environments. We argue that using them in such environments is the path to unleash the full potential of smart contracts. Compared to the contract enforcement mechanisms characterized by traditional contract law or relational contracts, smart contracts can offer a superior solution for facilitating trade.Several lawyers and economists have debated whether smart contracts might offer the prospect of cheaper, faster and better transactions. As we discuss below, contract law scholars caution that they neither replicate the relational context essential for the day-to-day practice of contracting nor offer a superior solution to problems addressed by traditional contract law, such as contract validity and legality. We clarify and systematize the current thinking on the legal nature and reliability of smart contracts, and address the concerns of contract law scholars. While doing that, we suggest a step forward in characterizing contracting environments, contract enforcement mechanisms and the trust relationship underlying contracts.     

Confirmation by LC–MS of drugs in oral fluid obtained from roadside testing

The aim of this study was to assess the effectiveness of two current on-site oral fluid (OF) drug detection devices (OraLab and Dräger), as part of the Spanish participation in the Roadside Testing Assessment Project (ROSITA Project). The study was done in collaboration with the Spanish Traffic Police, in Galicia (NW Spain), during 2004 and 2005. A total of 468 drivers selected at the police controls agreed to participate through informed consent. In addition, saliva samples were collected and sent to the laboratory to confirm the on-site results. For this purpose, two different analytical liquid chromatography–mass spectrometry (LC–MS) methods were used to detect 11 drugs or metabolites in a 300 μL sample. Simultaneous analysis of morphine, 6-acetylmorphine, amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB, cocaine and benzoylecgonine was carried out using 100 μL of oral fluid, after an automated solid phase extraction. A different LC–MS method was performed to detect Δ⁹-THC in 200 μL of oral fluid using liquid–liquid extraction with hexane at pH 6. Both methods were fully validated, including linearity (1–250 ng/mL, 2–250 ng/mL) recovery (>50%), within-day and between-day precision (CV < 15%), accuracy (mean relative error < 15%), limit of detection (0.5 and 1 ng/mL), quantitation (1 and 2 ng/mL) and matrix effect. All of the positive cases and a random selection of 30% of the negatives were analyzed for confirmation analysis. Good results (sensitivity, specificity, accuracy, positive predictive value and negative predictive value > 90%) were obtained for cocaine and opiates by OraLab, and for cocaine by Dräger. However, the results for the other compounds could be improved for both detection devices. Differences in the ease of use and in the interpretation mode (visual or instrumental) were observed.     

Ethical aspects of scientific progress

Ethics and science are much more closely connected than some people assume. Erroneous perceptions of the nature of ethics are the probable cause of this. Ethics is an intrinsic and productive component of scientific work, not some external or retrospective obstruction of “real” scientific research. The ethical component is positively influenced by a thorough knowledge of the discipline it belongs to. Science thrives in a climate of freedom, but this must not be used as an alibi to circumvent social responsibility and ethical concern. Ethical science has a direct bearing on science policy. Giving due attention to the ethical aspect of scientific work leads to several tangible results. It increases interdisciplinary openness, it promotes the communicability of science, and, ideally, it demonstrates the difference between knowledge and wisdom. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Linkage between Security,Governance and Development: the European Union in Africa

The international community currently favours an approach to development that stresses a triangular linkage between security, good governance and economic development. This approach clearly informs the European Union's agenda in Africa, which has progressively integrated governance and security elements. This paper will show that this agenda is at least as much determined by the bureaucratic and national affiliations of the concerned EU actors as it is by African realities and international trends. African security indeed triggers a competition between the different European institutions, eager to be the driving force for a policy that can offer some additional resources and autonomy. The consistency and the credibility of the EU security policy in Africa will therefore depend on the responses provided to these institutional rivalries.     

Capital and Labour Mobility and their Impacts on Mexico's Regional Labour Markets

Abstract

This paper studies the effects of capital and labor mobility on real wages across Mexican states for the period 1997–2006. Employing dynamic panel data methods, we find: (1) strong positive effects on real wages from foreign direct investment (FDI) and from migration; (2) domestic and foreign migration provide similar wage effects; and (3) alternative partitions indicate that real wages are more sensitive to FDI-related fluctuations across states with relatively lower wages and migration levels. Overall, these results provide support that real wages respond positively to fluctuations in capital flows and labour movements as predicted from the theory.