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631.
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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
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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
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Evaluating the Accuracy of Cranial Indices in Ancestry Estimation Among South African Groups
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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
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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
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Beatriz Cuadrado Ballesteros Isabel M. García Sánchez José M. Prado Lorenzo 《International Public Management Journal》2013,16(1):53-84
ABSTRACT The process of local decentralisation of public services delivery has attracted research attention because of the wide range of factors that induce governments to make this decision. Nonetheless, most such studies have focused on economic and financial aspects, ignoring the impact of political factors. The scarce previous research about political factors is the motivation for this study. We used panel data models based on 153 Spanish municipalities with populations over 50,000 for the period 1999–2007. The process of decentralisation is disaggregated according to the legal form of the entities: corporations and foundations. Our results show that more corporatisation processes are carried out in environments where political competition is lower and the party in power enjoyed greater support in the last elections. Additionally, decentralisation processes usually take place in the years immediately following elections, especially through foundations. Furthermore, both forms of decentralisation are more likely to be initiated by right-wing politicians. 相似文献
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Michel Tétu A. H. Le Q. Clayton André Lux Wilfrid M. Dubé Guy Bernard Claude Marchand 《Canadian journal of African studies》2013,47(1):115-129
This article follows the efforts of white settlers to impose cotton as an export crop in Natal and Zululand. Touted as a commodity capable of remaking land and life in the region in the 1850s, the 1860s, and again in the 1910s and 1920s, cotton never achieved more than marginal status in the region's agricultural economy. Its story is one of historical amnesia: although faith in the region's cotton prospects dipped following each spectacular failure, it was routinely resurrected once previous failures had been accounted for, or memories of them had faded. Two crucial issues are at the centre of this episodic history. First, I explore the logistics of planned expansion, and the reasons for the repeated collapse of cotton-growing schemes. Second, I unravel the side effects of these difficult and disappointing efforts and argue that, despite repeated failure, cotton facilitated important structural changes to the region's agricultural, political and economic landscape. 相似文献