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We consider perfectly anticipated periodic tax amnesties characterized by a tax rate lower than the ordinary one and used by a monopolistic government to maximize net fiscal revenue. We model tax amnesties as a form of intertemporal price discrimination. It turns out that, under certain conditions, discrimination secures the highest net revenue, as amnesties incorporate a self-selection mechanism that renders it possible to collect additional payments from tax evaders, without inducing honest taxpayers to join them. Optimal timing for granting tax amnesties may be calculated, but problems of time inconsistency in government behavior may arise.  相似文献   
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We report the results of Spanish and Portuguese working group (GEP) of International Society of Forensic Genetics (ISFG) Collaborative Exercise 2001-2002 on mitochondrial DNA (mtDNA) analysis. 64 laboratories from Spain, Portugal and several Latin-American countries participated in this quality control exercise. Five samples were sent to the participating laboratories, four blood stains (M1-M4) and a sample (M5) consisting of two hair shaft fragments. M4 was non-human (Felis catus) in origin; therefore, the capacity of the labs to identify the biological source of this sample was an integral part of the exercise. Some labs detected the non-human origin of M4 by carrying out immuno-diffussion techniques using antihuman serum, whereas others identified the specific animal origin by testing the sample against a set of animal antibodies or by means of the analysis of mtDNA regions (Cyt-b, 12S, and 16S genes). The results of the other three human blood stains (M1-M3) improved in relation to the last Collaborative Exercises but those related to hairs yielded a low rate of success which clearly contrasts with previous results. As a consequence of this, some labs performed additional analysis showing that the origin of this low efficiency was not the presence of inhibitors, but the low quantity of DNA present in these specific hair samples and the degradation.As a general conclusion the results emphasize the need of external proficiency testing as part of the accreditation procedure for the labs performing mtDNA analysis in forensic casework.  相似文献   
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Under the traditional socialist central planning system, economic growth in China and Vietnam was unstable and not very satisfactory. Yet, both countries achieved a remarkable progress in the area of human development. Later, under the market socialist model, China and Vietnam achieved very high rates of GDP growth, and malnutrition declined significantly. Yet, income distribution and the provision of key public services deteriorated in both countries. Progress in reducing child mortality in China was relatively slow, before improving in the early 2000s. Although Vietnam is much poorer than China, and has been growing less fast, its record in this area was markedly better. We show that this apparent paradox is due mainly to the fact that the negative side-effects of market-oriented reforms have reached a more advanced and alarming stage in China than in Vietnam. Our results also suggest that an additional factor is constituted by a relatively better status of women in Vietnam with respect to China. However, we also warn that signs are emerging in Vietnam too, indicating that it is entering a stage of development where the social problems now evident in China are starting to manifest themselves on a large and worrying scale. Our policy conclusions advocate in favour of re-establishing (in a new form, compatible with the maintenance of the economic dynamism of the market socialist system) some positive features of the pre-reform socialist model, among which universal public provision of basic public services is paramount.
Alberto GabrieleEmail:
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This article focuses on the Italian and Spanish models of growth and analyses labour market, human capital and innovation policy reforms since the mid 1990s. The comparison with France and Germany shows the constraints that have hindered the rise of institutional complementarities and the competitiveness of the two Mediterranean countries already before the introd uction of the euro and the outbreak of the 2008 crisis. The analysis highlights both similarities and structural differences between Italy and Spain and demonstrates the long-term institutional conditions that explain why the economic breakdown has had such a deep impact on the two countries.  相似文献   
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Currently, aluminum stub with carbon adhesive devices are used to collect inorganic gunshot residues (GSR) from the hands of a shooter. In an ideal shooting case, the gunshot particles do not persist for more than 2 h in the hands of the shooter, provided that the hands have not been washed. However, for forensic analysis and inference, the extended persistence of GSR would be desirable. This study investigates a novel GSR sampling and detection protocol. Sampling was performed in the nostrils using swab devices impregnated in ethylenediaminetetraacetic acid (EDTA). The GSRs persisted for longer periods in nasal mucus than on the hands, and particles were detected 6 h after shooting occurred. The analytical determination was conducted by scanning laser ablation-inductively coupled plasma-mass spectrometry (SLA-ICPMS) which enable the identification of the number of particles and their elemental composition. Seventeen isotope signals corresponding to 13C, 205Tl and 15 analytes that are usually associated with the composition of GSR residues were monitored: 27Al, 29Si, 31P, 33S, 35Cl, 39K, 44Ca, 57Fe, 60Ni, 63Cu, 66Zn, 118Sn, 121Sb, 137Ba, and 208Pb. The SLA technique enabled the reduction of the swab analysis time to 40 min. The effectiveness of this methodology was evaluated with two types of firearms: a pistol and a shotgun. The results indicated that the methodology proposed for the analysis of the nasal GSR was effective and that it can improve or complement the forensic analyses and inferences presented in a court.  相似文献   
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