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721.
722.
The present article tests predictions of rational political business cycle models using a large and previously unexplored data set of Portuguese municipalities. This data allows for a clean test of these predictions due to the high level of detail on expenditure items, an exogenous fixed election schedule, and homogeneity of Portuguese local governments with respect to policy instruments and institutions. Estimation results clearly reveal the opportunistic behaviour of local governments. In pre-electoral periods, they increase total expenditures and change their composition favouring items that are highly visible to the electorate. This behaviour is consistent with an effort to signal competence and increase chances of re-election. 相似文献
723.
Allele and haplotype frequencies of 15 chromosome STR loci included in the kit PowerPlex16 System from Promega, were determined in a sample of unrelated males from Guiné-Bissau, a country from the west African coast. All individuals were subjected to an interview in order to make sure that their ancestors belonged to the same ethnic group. This way we intended to look for possible inter-ethnic differences. PowerPlex 16 includes STRs not studied before in any multi-ethnic population. The kit includes two new allele markers (Penta D and Penta E), which are very useful either in forensics or population genetic studies. The Guinean population presents significant differences when compared with other African populations. 相似文献
724.
725.
Evaluating the Accuracy of Cranial Indices in Ancestry Estimation Among South African Groups 下载免费PDF全文
Leandi Liebenberg M.Sc. Kyra E. Stull Ph.D. Ericka N. L'Abbé Ph.D. Deona Botha M.Sc. 《Journal of forensic sciences》2015,60(5):1277-1282
Historically, population differences were quantified using cranial indices. Even though the application of indices is associated with numerous statistical and methodological problems, the use of cranial indices to estimate ancestry persists as demonstrated by its inclusion in several recent papers and conference presentations. The purpose of this study was to classify 207 South African crania and compare the results of five standard cranial indices to linear discriminant analysis (LDA). New sectioning points were created to contend with low classification accuracies (40–79%) and possible secular trends. Although the accuracies of the new sectioning points increased (66–87%), the accuracies associated with the stepwise LDA were higher (84%) and could classify the crania into one of the three South African groups. The results of the study demonstrate that indices cannot compete with multivariate techniques and should not be used in forensic anthropological analyses for ancestry estimation. 相似文献
726.
727.
Frédéric Savall M.D. Marie Faruch-Bilfeld M.D. Fabrice Dedouit M.D. Ph.D. Nicolas Sans M.D. Ph.D. Hervé Rousseau M.D. Ph.D. Daniel Rougé M.D. Ph.D. Norbert Telmon M.D. Ph.D. 《Journal of forensic sciences》2015,60(6):1395-1400
Decision trees provide an alternative to multivariate discriminant analysis, which is still the most commonly used in anthropometric studies. Our study analyzed the metric characterization of a recent virtual sample of 113 coxal bones using decision trees for sex determination. From 17 osteometric type I landmarks, a dataset was built with five classic distances traditionally reported in the literature and six new distances selected using the two-step ratio method. A ten-fold cross-validation was performed, and a decision tree was established on two subsamples (training and test sets). The decision tree established on the training set included three nodes and its application to the test set correctly classified 92% of individuals. This percentage was similar to the data of the literature. The usefulness of decision trees has been demonstrated in numerous fields. They have been already used in sex determination, body mass prediction, and ancestry estimation. This study shows another use of decision trees enabling simple and accurate sex determination. 相似文献
728.
Maíra Kerpel dos Santos PhD Alexander Acosta PhD Ryan Capote BS Bakhtawar Tabassam BS James Ley PhD Martin Quirke PhD José Almirall PhD 《Journal of forensic sciences》2023,68(4):1162-1177
The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test. 相似文献
729.
André Luiz Reis da Silva Alexandre Piffero Spohr Isadora Loreto da Silveira 《South African Journal of International Affairs》2016,23(2):167-184
This article aims to trace South–South cooperation political lineages connecting the Non-Aligned Movement and the IBSA (India, Brazil, South Africa) Forum. In order to determine whether IBSA could be considered the ‘heir’ to Bandung's principles, we analyse the concepts of ‘Third World’ and ‘Global South’ as well as their current applicability, the interpretations provided by existing literature on the IBSA grouping, and its member countries' shared views on different issues of the international agenda. The article also considers the historical evolution of ‘Southern’ diplomatic thought and actions. IBSA's actions and history, as well as its members, are studied to grasp how they are related to the Third World movement in the Cold War. 相似文献
730.
José Octavio Velázquez Gomar 《International Environmental Agreements: Politics, Law and Economics》2016,16(4):525-541
The system of multilateral environmental agreements (MEAs) comprises hundreds of conventions and protocols designed to protect the environment. Institutional interaction within the MEA system raises issues of environmental policy integration (EPI), i.e. balancing different environmental objectives and considerations. Mainstream proposals for enhancing EPI in environmental governance build upon the assumption that environmental institutions are fragmented. However, recent research reveals that the MEA system has been defragmenting over the years such that EPI is less a problem of institutional fragmentation than of effective management of institutional interplay. This paper examines the factors affecting EPI among MEAs by looking at experiences in the cluster of biodiversity-related multilateral agreements. The analysis is based on a series of interviews with MEA secretariat officials and international experts conducted between September 2011 and January 2012. The paper identifies institutional, political and cognitive barriers constraining interplay management efforts. While some have proposed regulatory changes in the cluster, national-level co-ordination appears to be the best way to advance EPI. 相似文献