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Catanesi R Carabellese F Troccoli G Candelli C Grattagliano I Solarino B Fortunato F 《Forensic science international》2011,210(1-3):149-153
Bone marrow (BM) analysis is of forensic interest in postmortem toxicological investigation in case of limited, unavailable or unusable blood samples. However, it remains difficult to determine whether a drug BM concentration is therapeutic or represents overdose, due to the lack of studies on this alternative matrix. Given the variations in BM composition in the body, sample location was suggested to be a relevant factor in assessing BM concentration. The aim of the present study was to compare postmortem caffeine concentrations in various BM sample locations and secondly to consider the correlation between BM and blood concentrations. Six BM samples (right and left side: proximal and medial femur and 5th rib) and a blood sample were collected from 21 forensic autopsies. Gas chromatography coupled to tandem mass spectrometry was performed. Blood caffeine concentrations ranged from 60 to 7591ng/mL. Femoral and rib BM concentrations ranged from 51 to 6171ng/g and 66 to 7280ng/g, respectively. Blood concentrations were always higher than BM concentrations. As a good correlation was demonstrated between blood and rib BM and between blood and the average of the four femoral BM concentrations, blood caffeine concentrations could be correctly extrapolated from BM concentrations. BM caffeine concentration was found to depend on sample location. Rib BM caffeine concentrations appeared to be systematically greater than averaged femur values and concentrations were much more variable between the 4 femur BM samples than between the 2 ribs. From a practical point of view, for caffeine analysis, rib BM appeared more relevant than femoral BM, which requires multisampling to overcome the concentration variability problem. 相似文献
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Arca S Campadelli P Lanzarotti R Lipori G Cervelli F Mattei A 《Journal of forensic sciences》2012,57(3):765-771
Face recognition systems aim to recognize the identity of a person depicted in a photograph by comparing it against a gallery of prerecorded images. Current systems perform quite well in controlled scenarios, but they allow for none or little interaction in case of mistakes due to the low quality of images or to algorithmic limitations. Following the needs and suggestions of investigators, we present a guided user interface that allows to adjust from a fully automatic to a fully assisted modality of execution, according to the difficulty of the task and to amount of available information (gender, age, etc.): the user can generally rely on automatic execution and intervene only on a limited number of examples when a failure is automatically detected or when the quality of intermediate results is deemed unsatisfactory. The interface runs on top of a preexistent automatic face recognition algorithm in such a way to guarantee full control over the execution flow and to exploit the peculiarities of the underlying image processing techniques. The viability of the proposed solution is tested on a classic face identification task run on a standard publicly available database (the XM2VTS), assessing the improvement to user interaction over the automatic system performance. 相似文献
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A major policy concern regarding patenting activity is related to the actual enforceability of the patents granted by Patent Offices. The risk of facing elevated legal costs to defend patent rights can affect ex-ante incentives to invest in R&D. This paper analyses whether the availability of insurance policies that cover legal expenditures for patent litigation could increase the appropriability of the innovation. We model a situation in which an incumbent innovator is endowed with a valid patent and an entrant imitator can either directly enter the market or try to apply for a patent, hoping that an error will be made by the Patent Office. The incumbent can accommodate the entrant, file a suit to a civil court or offer a settlement agreement. We model the presence of heterogeneity in the risk that the patents will face an error by both patent examiners at Patent Offices and judges at civil court. We analyse the changes in expected profits for the innovator when given the possibility of buying an insurance policy which will cover legal costs in the event of trial. We compare the cases in which (i) coverage is voluntary and the insurer can discriminate perfectly between risky patents; (ii) coverage is voluntary and the insurer cannot discriminate between patents, and (iii) coverage is compulsory. The model highlights a set of peculiar strategic characteristics of insurance for legal expenditures which contribute to singling out the reasons underlying the underdevelopment of this market. We suggest that the crucial reason for such a failure is not adverse selection; consequently, we challenge the benefits of making coverage compulsory. 相似文献
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In this paper we revisit Tullock's paradox (Tullock, 1980) and consider a rent-seeking game in which parties face increasing returns to effort. We allow parties to randomize their strategies and give them an exit option. Given the mixed participation strategies of the parties, valuable rents may occasionally remain unexploited. We consider such a lost-treasure effect as an additional cost of rent seeking and examine how the expected value of such a lost rent varies with changes in the parameters of the problem. 相似文献
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The claim that in policy games nonneutrality and a stagflation bias emerge in equilibrium if the unions care about inflation, per se, is discussed. This assumption is shown to be not necessary to obtain a stagflation bias; the same applies to nonneutrality if a government acts in the economy. The question of whether unions should be envisaged as “institutions” (i.e., interested in variables unrelated to wages and employment) is also addressed. Two model-based alternatives providing “microeconomic” foundations versus “macroeconomic” foundations to unions' behaviour are presented. The conclusion is that the modelling of unions remains an unsettled problem. 相似文献
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Giuseppe Eusepi 《Public Choice》1995,82(3-4):307-324
Italian public broadcasting service (RAI) has had a monopoly until the middle of the 1970s. The peculiarity of public monopoly in broadcasting is its tendency to secure political rather than economic rents. The dangers that public monopoly causes to consumers (viewers-listeners), has not emerged at least until the mid-seventies for the simple reason that broadcasting has been conceived under the ideological umbrella of public good rather than in terms of opportunity costs. A law limiting monopoly has taken fourteen years to be passed so that the proliferation of private radio and television stations has orgininated the subrogatory intervention by the Constitutional Court. From 1975 to 1989 regulation has tended to perpetuate RAI's monopoly, in a context which was very different from the one in which the RAI was established. It is no wonder, therefore, that reforms have been motivated by RAI's financial crisis in the seventies and eighties, and not by political choices. The 1990 law puts a stop to public monopoly in broadcasting giving rise to what now appears to be a duopoly, but which in 1990 to many seemed to introduce a contestable market able to respond to both consumers' demand and technological innovations more efficiently, so ensuring more freedom of information. 相似文献
40.
Quack medicines were prepackaged, commercially marketed medicinal concoctions brewed from “secret recipes” that often contained powerful drugs. Governmental regulation of them in late nineteenth-century England is heralded as a landmark of public health policy. We argue that it’s instead a landmark of medicinal rent-seeking. We develop a theory of quack medicine regulation in Victorian England according to which health professionals faced growing competition from close substitutes: quack medicine vendors. To protect their rents, health professionals organized, lobbied, and won laws granting them a monopoly over the sale of “poisonous” medicaments, most notably, quack medicines.
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