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91.
Normally, the identification of the LSD drug is performed by forensic laboratories, using the Ehrlich spot test. However, this is a nonspecific analysis. Additionally, the Brazilian Federal Police has identified the presence of a new compound in seized blotters: 9,10-dihydro-LSD, an uncontrolled substance. In this work, easy ambient sonic-spray ionization mass spectrometry in the positive ion mode, EASI(+)-MS, was used to characterize LSD and 9,10-dihydro-LSD compositions directly from the surface of blotters. The presence of LSD in the seized blotter samples were also confirmed via high-performance liquid chromatography with ultraviolet detector. In a set of 41 blotters analyzed by EASI(+)-MS, 28 showed positive results for LSD, seven for 9,10-dihydro-LSD, and another six samples showed negative results for both LSD and 9,10-dihydro-LSD. The combination of thin layer chromatography with EASI-MS also demonstrated to be a relatively simple and powerful screening tool for forensic analysis of street drugs.  相似文献   
92.
Oxelytrum discicolle is a carrion beetle commonly found in the Neotropical region, mainly associated with cadavers and carcasses. Information on behavior related to the likelihood of cadaver colonization is scarce. We performed two field experiments in peri‐urban forest in Brazil in order to strengthen our knowledge on O. discicolle behavior. In the first experiment, we assessed the preference for piglet carcasses at different stages of decomposition offered simultaneously in two seasons, dry and rainy, while in the second experiment we investigated the diel activity of adults. A total of 493 adults were collected in the experiments. A significantly higher abundance was detected in the rainy season. There was a marked preference for carcasses at advanced stages. Adults exhibited a typical nocturnal behavior, the number trapped at night was 17 times greater than those collected during the day. Oxelytrum discicolle is nocturnal species that prefers carcasses in advanced stage of decomposition.  相似文献   
93.
Various technical methods were investigated with the aim of developing a multiplex system to amplify five Y-chromosome STR loci in the same PCR reaction: DYS393, DYS19, DYS390, DYS389 I and DYS389 II. A sequenced allelic ladder was constructed with previously sequenced alleles including the most common ones. A number of reamplification conditions of the allelic ladders were tested. The pentaplex was evaluated for typing using two different platforms (ABI and ALF) with promising results. However, in degraded samples non-specific artifacts were observed in the DYS393 system in the same range of sizes as the real alleles. This system can also be typed in females under relatively low stringency conditions in the PCR amplification, making this system prone to errors in critical samples. This lack of specificity can be reduced by increasing the stringency of the PCR conditions. The DYS19 ladder cannot be reamplified as stutters appear after a few reamplifications. These stutters are probably due to a 2 bp slippage induced by the presence of a TA repeat stretch in the PCR amplified fragments. Non-specific products were also noted in the DYS389 I and DYS389 II amplification, although out of the range of other alleles in this pentaplex. This newly constructed pentaplex has proved to be very useful in population genetic studies because all five Y STR markers can be loaded in the same lane of a gel with other Y STR singleplex or multiplexes. The usefulness of Y-chromosome STRs in criminal casework is especially evident in analyzing azoospermic individuals.  相似文献   
94.
Haplotype, allele frequencies and population data of 17 Y-chromosome STR loci DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460 (GATA A7.1), DYS461 (GATA A7.2), GATA A10, GATA C4 and GATA H4 were determined from a sample of 148 unrelated male individuals from Spain. A total of 144 haplotypes were identified by the 17 Y-STR markers, of which 141 were unique, two were found in two individuals and one was found in three individuals. The haplotype diversity (99.95%) and discrimination capacity (97.30%) were calculated. Comparisons were made with previously published haplotype data on other Iberian population samples and no significant differences were found.  相似文献   
95.
ABSTRACT

Tourism is a viable, but risky, option for many small island countries to integrate and compete in the world economy. This article examines tourism in the small island economy of Cape Verde. It assesses the risks to its long term development posed by the industry. The country has one of the fastest growing tourism industries in the world. However, this rapid growth is a dual-edge sword. Tourism-led growth results in real economic gains. However, the type and organisation of Cape Verde’s tourism industry magnifies the country’s already high structural vulnerability. Given its current structure and pace of growth, tourism increases macroeconomic risks and vulnerability. It is reproducing the same monoculture dependency that traditionally hampered development in African economies. The policy lessons are clear. Cape Verde must foster economic diversification while simultaneously engaging in strategies to mitigate the risks that accompany its biggest and fastest growing sector and export.  相似文献   
96.
A choking death of a healthy fisherman, who put a type of live sole between his jaws to free up his hands so that he could collect more fish to put into his basket, is described. The fish squirmed into the larynx and upper trachea and the attempts to rescue the man by his colleagues who used pliers did not succeed, and the man died. Other published cases are reviewed, and risk factors and rescue possibilities discussed.  相似文献   
97.
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   
98.
The Spanish and Portuguese ISFG Working Group (GEP-ISFG) carried out a collaborative exercise in order to asses the performance of two Y chromosome STR tetraplexes, which include the loci DYS461, GATA C4, DYS437 and DYS438 (GEPY I), and DYS460, GATA A10, GATA H4 and DYS439 (GEPY II). The groups that reported correct results in all the systems were also asked to analyse a population sample in order to evaluate the informative content of these STRs in different populations. A total of 1020 males out of 13 population samples from Argentina, Brazil, Costa Rica, Macao, Mozambique, Portugal and Spain were analysed for all the loci included in the present study. Haplotype and allele frequencies of these eight Y-STRs were estimated in all samples. The lowest haplotype diversity was found in the Lara (Argentina) population (95.44%) and the highest (99.90%) in Macao (China). Pairwise haplotype analysis showed the relative homogeneity of the Iberian origin samples, in accordance with what was previously found in the European populations for other Y-STR haplotypes (http://www.ystr.org). As expected, the four non-Caucasian samples, Macao (Chinese), Mozambique (Africans), Costa Rica (Africans) and Argentina (Lara, Amerindians), show highly significant Phist values in the pairwise comparisons with all the Caucasian samples.  相似文献   
99.
Public Choice - In this paper, we show how results in state administered university entrance standardized exams in Portugal are sensitive to the electoral cycle. Using individual data for all...  相似文献   
100.
Characterization of lesions in hanging deaths   总被引:1,自引:0,他引:1  
Hanging is a common method of committing suicide and a routine task in medico-legal autopsies. The hanging mark is the most relevant external sign and its characteristics are well known, but, for unknown reasons, there are major differences in reports on internal findings. We retrospectively studied 228 consecutive cases of hanging deaths. A complete standard autopsy was performed for every case. We investigated the association between the characteristics of the hanging mark and the frequency of bone, cartilage, soft tissue, and vascular injuries with the mode of suspension. Most cases (75.3%) presented some kind of bone or cartilage fracture, but these were unrelated to any of the variables studied. Vascular lesions are clearly more infrequent: intimal injuries were found in the carotid artery (9.1%), the jugular vein (2.2%), and ruptures of the carotid adventitial layer (21.7%). These could be partially associated with the use of a hard fixed noose and body weight.  相似文献   
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