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791.
Christina Staginnus Ph.D. Siegfried Zörntlein Ph.D. Etienne de Meijer Ph.D. 《Journal of forensic sciences》2014,59(4):919-926
Neither absolute THC content nor morphology allows the unequivocal discrimination of fiber cultivars and drug strains of Cannabis sativa L. unequivocally. However, the CBD/THC ratio remains constant throughout the plant's life cycle, is independent of environmental factors, and considered to be controlled by a single locus (B) with two codominant alleles (BT and BD). The homozygous BT/BT genotype underlies the THC‐predominant phenotype, BD/BD is CBD predominant, and an intermediate phenotype is induced by the heterozygous state (BT/BD). Using PCR‐based markers in two segregating populations, we proved that the THCA synthase gene represents the postulated B locus and that specific sequence polymorphisms are absolutely linked either to the THC‐predominant or the THC‐intermediate chemotype. The absolute linkage provides an excellent reliability of the marker signal in forensic casework. For validation, the species‐specific marker system was applied to a large number of casework samples and fiber hemp cultivars. 相似文献
792.
Inés de Águeda Corneloup Arthur P. J. Mol 《International Environmental Agreements: Politics, Law and Economics》2014,14(3):281-297
Being at the frontline of climate change, small island developing states (SIDS) hold a serious stake in climate negotiations. However, these countries usually are marginalized in the international political arena, due to their lack of structural power. This paper explores the strategic influence of SIDS and its representative organization, the Alliance of Small Island States, in the negotiations leading to the Copenhagen summit of December 2009. Using the concepts of leadership and discourses, the position, strategies, and impact of SIDS are analyzed on negotiation processes and their final outcome, focusing on three core demands of small island countries at Copenhagen: a temperature rise limit of 1.5 °C above preindustrial levels, funding for adaptation, and a legally binding outcome. Results reveal that SIDS practiced entrepreneurial, intellectual, and environmental leadership strategies and especially made use of moral claims in the debate. Given their near absence of structural power, they managed to secure a surprisingly large part of “their” agenda and interests in the final Copenhagen Accord, especially through (discourse) coalitions with various other state and non-state stakeholders. 相似文献
793.
794.
While the popularity of using the item count technique (ICT) or list experiment to obtain estimates of attitudes and behaviors subject to social desirability bias has increased in recent years among political scientists, many of the empirical properties of the technique remain untested. In this paper, we explore whether estimates are biased due to the different list lengths provided to control and treatment groups rather than due to the substance of the treatment items. By using face-to-face survey data from national probability samples of households in Uruguay and Honduras, we assess how effective the ICT is in the context of face-to-face surveys—where social desirability bias should be strongest—and in developing contexts—where literacy rates raise questions about the capability of respondents to engage in cognitively taxing process required by ICT. We find little evidence that the ICT overestimates the incidence of behaviors and instead find that the ICT provides extremely conservative estimates of high incidence behaviors. Thus, the ICT may be more useful for detecting low prevalence attitudes and behaviors and may overstate social desirability bias when the technique is used for higher frequency socially desirable attitudes and behaviors. However, we do not find strong evidence of variance in deflationary effects across common demographic subgroups, suggesting that multivariate estimates using the ICT may not be biased. 相似文献
795.
Luis Alfredo Vega Osuna Izaguirre Fridizia Diaz de Leon Sergio Alvarado Altamirano 《美中公共管理》2014,(8):650-663
In contemporary times, a fundamental aspect for organization has been to achieve innovation through culture and approach to encourage the search and development of new ideas, new products, and new services; this is a key point to fulfill the competitive advantages which a company needs to be successful in the global market. The Sinaloa horticultural company has more than 100 years' history in the United States export market, and is presenting new challenges and demands from the market in order for it to achieve its permanence. The objective of this research is to identify and propose different strategies to implement management innovation, which in its essence is the one that coordinates, directs, and controls the human resource considering culture as an integral part, with a capacity to generate the spark and function as a motivating source which drives companies to consolidate and integrate supply chains. 相似文献
796.
Legrand B Mazancourt Pd Durigon M Khalifat V Crainic K 《Forensic science international》2002,125(2-3):205-211
Formalin-induced DNA degradation was studied at different fixation times (3, 7, 16 and 32 days) each on 10 formalin fixed paraffin embedded tissues (FFPET) stored for 15 years at room temperature.The four different extraction protocols used in this study showed that Chelex100 extracts performed the best at 3 and 7 days of formalin fixation (DFF) (with regard to the quantity and the quality of the DNA). However, Qiamp extracts showed better results for long sized alleles, as well for single polymerase chain reaction (PCR) amplifications after 16 and 32 DFF, as for multiplex PCR at shorter fixation times. DNA degradation is expressed by the size of the amplified alleles, only 100 bp templates surviving after 32 DFF (AMG locus). Single locus amplifications (CD4 and FES/FPS alleles) performed better than multiplex PCR (ProfilerPlus), with nearly 100% positive results at 7 DFF. In both types of amplifications, the success rate decreased proportionally with the time of formalin fixation and, consequently, with the size of the required DNA template. 相似文献
797.
Real-time PCR designs to estimate nuclear and mitochondrial DNA copy number in forensic and ancient DNA studies 总被引:8,自引:0,他引:8
Alonso A Martín P Albarrán C García P García O de Simón LF García-Hirschfeld J Sancho M de La Rúa C Fernández-Piqueras J 《Forensic science international》2004,139(2-3):141-149
We explore different designs to estimate both nuclear and mitochondrial human DNA (mtDNA) content based on the detection of the 5' nuclease activity of the Taq DNA polymerase using fluorogenic probes and a real-time quantitative PCR detection system. Human mtDNA quantification was accomplished by monitoring the real-time progress of the PCR-amplification of two different fragment sizes (113 and 287 bp) within the hypervariable region I (HV1) of the mtDNA control region, using two fluorogenic probes to specifically determine the mtDNA copy of each fragment size category. This mtDNA real-time PCR design has been used to assess the mtDNA preservation (copy number and degradation state) of DNA samples retrieved from 500 to 1500 years old human remains that showed low copy number and highly degraded mtDNA. The quantification of nuclear DNA was achieved by real-time PCR of a segment of the X-Y homologous amelogenin (AMG) gene that allowed the simultaneous estimation of a Y-specific fragment (AMGY: 112 bp) and a X-specific fragment (AMGX: 106 bp) making possible not only haploid or diploid DNA quantitation but also sex determination. The AMG real-time PCR design has been used to quantify a set of 57 DNA samples from 4-5 years old forensic bone remains with improved sensitivity compared with the slot-blot hybridization method. The potential utility of this technology to improve the quality of some PCR-based forensic and ancient DNA studies (microsatellite typing and mtDNA sequencing) is discussed. 相似文献
798.
Demodex is an ectoparasite living in the skin as a nonpathogen or a pathogen. It is also known that demodex acts as a vector of pathogenic microorganisms. In this study, we have investigated the rate of occurrence and vitality of demodex in forensic autopsies that have a high risk of contamination by infected organisms. The study, which was cross-sectional, conducted on 100 autopsy cases: 77 of the bodies were male and 23 female. The average age was 41. The samples were taken from the forehead, nose, cheeks, eyelashes and the temporal areas using the standardized skin surface biopsy and hair epilation techniques that were modified for this study. The data obtained were assessed statistically. Demodex was determined in 10% of all the cases. The cases revealed that demodex increased in old age and was more frequently seen in people with fair complexion. It was most frequently found in the forehead and the cheek. The longest postmortem interval in the positive cases was 55 h. The relationship between the postmortem interval and the presence of demodex was not statistically significant. Considering the fact that demodex, which is transmitted from human to human through skin contact, acts as a vector of pathogenic organisms and can stay alive in dead bodies for a long time, we think that the personnel performing autopsies without taking the necessary precautions are under risk. 相似文献
799.
800.