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61.
62.
Here, we show a new, simple, and rapid SYBR Green-based Real-Time PCR assay for the quantification of hallucinogenic plants in plant mixtures. As a test plant, Salvia divinorum Epling & Játiva-M., a perennial herb belonging to the Lamiaceae family able to induce hallucinations, changes in perception, or other psychologically induced changes with similar potency as LSD, was used. The method was tested on seven mixtures 100/0%, 80/20%, 60/40%, 40/60%, 20/80%, 10/90%, 0/100% (w/w) S. divinorum versus a non-hallucinogenic plant, Salvia officinalis. Total DNA was extracted from samples and quantified by Real-Time PCR. Arabidopsis thaliana genomic DNA was added, as internal standard, at the beginning of each extraction. A new formula for the interpretation of Real-Time PCR data, based on the relative quantification of DNA extracted from mixture versus a reference DNA extracted from a known amount of pure S. divinorum, was developed. The results of this work show an almost perfect correspondence between Real-Time PCR-calculated weight and the weight estimated by an analytical weighted method, proving the effectiveness of this method for the quantitative analysis of a given species in a plant mixture.  相似文献   
63.
Drawing from Coase’s methodological lesson, this article discusses the specific case of knowledge, which was for a long time chiefly governed by exchange mechanisms lying outside the market, and has only recently been brought into the market. Its recent, heavy “colonization” by the property paradigm has progressively elicited criticism from commentators who, for various reasons, believe that the market can play only a limited role in pursuing efficiency in the knowledge domain. The article agrees with the enounced thesis and tries to provide an explanation of it that relates to the fact that in specific circumstances property-rights can produce distinct market failures that affect the social cost and can consequently prevent attainment of social welfare. In particular, the arguments set forth here concern three distinct externalities that arise when enforcing a property rights system over knowledge. First, the existence of a property right may itself alter individual preferences and social norms, thus causing specific changes in individuals’ behaviour. Second, the idiosyncratic nature of knowledge, as a collective and inherently indivisible entity, means that its full propertization can be expected to produce significant harm. Third, property rights can cause endogenous drifts in the market structure arising from the exclusive power granted to the right holder: though generally intended as a necessary mechanism for extracting a price from the consumer, in the knowledge domain property rights can become a device for extracting rents from the market.  相似文献   
64.
The most effective resuscitative procedure in choking by foreign bodies is the Heimlich maneuver, described for the first time by Henry Heimlich (1974) and recognized by the US Surgeon General (1985) as the "only method that should be used for the treatment of choking from foreign body airway obstruction." If performed correctly, this lifesaving maneuver is associated with rare complications, of which the most frequent are rib fractures and gastric or esophagus perforations. Other rare traumatic injuries such as pneumomediastinum, aortic valve cusp rupture, diaphragmatic herniation, jejunum perforation, hepatic rupture, or mesenteric laceration have been described.However, we are unaware of previous reports of splenic rupture after Heimlich maneuver. We present an interesting case of fatal hemoperitoneum due to a hilar laceration of the spleen following a correctly performed Heimlich maneuver.  相似文献   
65.
A novel application of replica molding to a forensic problem, viz. the accurate reproduction of the case head of gun and rifle cartridges, prior and after been shot, is presented. The fabrication of an arbitrary number of identical copies of the region hit by the firing pin and by the breech face is described. The replicas can be (i) handled without damaging the original evidence, (ii) distributed to different law enforcement agencies for comparison against other evidences found on crime scenes or ballistic tests of seized firearms, (iii) maintained on a file by the laboratories. A detailed analysis of the morphological features of the replicas has been carried out by standard microscopy techniques as well as by advanced microscopy such as scanning probe and scanning electron leading to a quantitative morphological characterization of the case heads down to the nanometer scale. The assignment of the cartridge replicas to the shooting weapon is demonstrated to hold below the micron scale, while it is hindered at the nanometer level both by the manufacturing differences and by eventual modifications occurring on the firing pin.  相似文献   
66.
A novel method based on microemulsion electrokinetic chromatography (MEEKC) with diode array detection (DAD) for rapid determination of caffeine in commercial and clandestine stimulants, known as "energy drinks" and "smart drugs", is described. Separations were carried out in 50 cm × 50 μm (ID) uncoated fused silica capillaries. The optimized buffer electrolyte was composed of 8.85 mM sodium tetraborate pH 9.5, SDS 3.3% (w/v), n-hexane 1.5% (v/v) and 1-butanol 6.6% (v/v). Separations were performed at a voltage of 20 kV. Sample injection conditions were 0.5 psi, 3 s. Diprofilline was used as internal standard. The determination of the analytes was based on the UV signal recorded at 275 nm, corresponding to the maximum wavelength of absorbance of caffeine, whereas peak identification and purity check was performed on the basis of the acquisition of UV radiation between 200 and 400 nm wavelengths. Under the described conditions, the separation of the compounds was achieved in 6 min without any interference from the matrix. Linearity was assessed within a caffeine concentration range from 5 to 100 μg/mL. The intra-day and inter-day precision values were below 0.37% for migration times and below 9.86% for peak areas. The present MEEKC method was successfully applied to the direct determination of caffeine in smart drugs and energy drinks.  相似文献   
67.
Abstract: A critical review of Kahana and Hiss’ study on identification from bone trabecular pattern and a test of their method conducted on the humerus are presented. Bone trabecular pattern was studied through the generation of a numerical file representing the gray scale. Using the correlation coefficient, several pairwise comparisons between numerical files were performed. The test gave nearly 30% of incorrect exclusions (the method did not recognize couples of radiographs belonging to the same subject) and 50% of misidentifications (the method recognized couples of radiographs belonging to different subjects, as belonging to the same subject); therefore, this research shows that at the present time, it is not possible to safely quantify identification through bone density patterns, of the proximal humerus taken from thoracic X‐rays. Thus, an “easy”—but dangerous—use of trabecular density patterns on this specific type of radiogram as an identification method should be currently avoided.  相似文献   
68.
Many homemade tamper processes of medical codeine formulations are available on selected “forums” on the Internet, where recreational codeine users claim to be able to purify codeine by removing additives, such as acetaminophen, to avoid or limit adverse effects. In this work, it is reported and discussed a fatal case of codeine intoxication. The findings of objects such as jars, filters, and tablets, and amounts of unknown liquid material at the death scene investigation suggested a fatal codeine intoxication after the tampering procedure called “cold water extraction.” Toxicological results obtained from the analysis of both the nonbiological material and the body fluids of the decedent integrated with the information collected at the death scene investigation confirmed the above‐mentioned hypothesis. This report underlines the importance of a tight interconnection between criminalistics and legal medicine to strengthen the identification of the cause of death and the reconstruction of the event.  相似文献   
69.
70.
An improved capillary gas chromatographic method for the analysis of illicit diamorphine preparation is reported. The method was able to resolve the impurities and more frequent adulterants and contaminants present in street heroin preparations with a diamorphine detection limit of 0.2 ng in split-less mode.  相似文献   
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