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211.
Amidst calls for more scrutiny of the failure of infrastructure public–private partnerships (PPPs), uncertainty about how we can measure failure remains, and little systematic evidence illuminates its likelihood. Our mixed‐methods design explores the notion of failure and identifies the conditions under which it happens. The first phase of our research employs documentary analysis and semistructured expert interviews, and identifies project cancellation as capturing the most severe occurrences of failure. A second phase statistically analyzes a unique World Bank data set capturing the provisions of over 4,000 infrastructure PPPs launched between 1990 and 2015 in 89 countries. We find robust evidence supporting the theoretical claim that PPPs are less likely to be canceled in countries with more veto points among their political institutions to restrain politicians from intervening in policy implementation. Cancellation is a rare, but valid indicator of failure, and the importance of veto players clarifies how political risk operates in this context. 相似文献
212.
Innovating upon previous field experiments and theories of identity‐based discrimination, we test whether public officials are using searches (“identity‐questing”) to profile citizens and acting on latent biases. Pairs of “institutional” and “noninstitutional” requesters send lower and moderate burden freedom of information (FOI) requests—providing no identity cues apart from undistinctive names, e‐mails, and ID numbers—to nearly 700 of Brazil's largest municipalities. Results show institutional requesters receive one‐fifth more responses than noninstitutional comparators. For moderate versus lower burden requests, noninstitutional requesters are 11% less likely to receive a compliant response than their institutional comparators. The only plausible explanation for these results is identity‐questing, a phenomenon that has far‐reaching policy implications. Most of the world's FOI laws, for example, contain vague ID obligations, which translate incoherently from laws to regulation and practice. Results enjoin public service providers to protect the identities of citizens by default or upon request. 相似文献
213.
Youngmin Kim M.S. Won-sil Choi Ph.D. Byoungjun Jeon B.S. Tae Hyun Choi M.D. Ph.D. 《Journal of forensic sciences》2020,65(2):458-464
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation. 相似文献
214.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications. 相似文献
215.
Hari Jang M.S. Sang Eon Shin Ph.D. Kyu Jin Youm B.S. Mustafa Zafer Karagozlu Ph.D. Chang Bae Kim Ph.D. Kwang Soo Ko M.S. Seong Hwan Park M.D. Ph.D. 《Journal of forensic sciences》2020,65(1):283-287
Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea. 相似文献
216.
Terezie Cernosek B.S. Kevin E. Eckert M.Sc. David O. Carter Ph.D. Katelynn A. Perrault Ph.D. 《Journal of forensic sciences》2020,65(1):134-143
Volatile organic compounds (VOCs) are by-products of cadaveric decomposition and are responsible for the odor associated with decomposing remains. The direct link between VOC production and individual postmortem microbes has not been well characterized experimentally. The purpose of this study was to profile VOCs released from three postmortem bacterial isolates (Bacillus subtilis, Ignatzschineria indica, I. ureiclastica) using solid-phase microextraction arrow (SPME Arrow) and gas chromatography–mass spectrometry (GC-MS). Species were inoculated in headspace vials on Standard Nutrient Agar and monitored over 5 days at 24°C. Each species exhibited a different VOC profile that included common decomposition VOCs. VOCs exhibited upward or downward temporal trends over time. Ignatzschineria indica produced a large amount of dimethyldisulfide. Other compounds of interest included alcohols, aldehydes, aromatics, and ketones. This provides foundational data to link decomposition odor with specific postmortem microbes to improve understanding of underlying mechanisms for decomposition VOC production. 相似文献
217.
Owen Esaias M.Sc. Grant W. Noonan D.P.S. Shane Everist M.Sc. Michell Roberts B.B.Sc. Cassie Thompson M.Sc. Matt N. Krosch Ph.D. 《Journal of forensic sciences》2020,65(3):722-728
An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation. 相似文献
218.
Ju Yeon Jung M.S. Ga Hee Ryu B.S. Da-Hye Kim B.S. Joo-Young Kim Ph.D. In Kwan Hwang Ph.D. Pil-Won Kang Ph.D. Byung Won Chun Ph.D. Seong Yeon Yoo Ph.D. 《Journal of forensic sciences》2020,65(1):209-213
When using non-FTA cards in commercial multiplex STR kits for direct PCR, pretreatment steps with specific buffers are recommended. Here, we designed a rapid direct PCR method utilizing a non-FTA card, Oral Cell Sampling Kit, by omitting the pretreatment step involving Prep-n-Go™ Buffer, and it showed compatibility with the GlobalFiler™ Express PCR Amplification Kit, GlobalFiler™ PCR Amplification Kit, and PowerPlex® Fusion system. To optimize the PCR conditions, we tested the method with different final PCR volumes and cycles. Finally, we conducted a performance test using 50 Korean buccal samples and confirmed the high performance of the method, detecting more than 90% of the samples with full profiles when using GlobalFiler™ PCR Amplification Kit and PowerPlex® Fusion system at 29 cycles in a 10 μL final PCR volume. Thus, we report a simple direct PCR set-up to analyze reference samples collected using a non-FTA card manufactured in Korea. 相似文献
219.
Mamiko Fukuta M.D. Ph.D. Tetsuya Horita M.D. Yoshimi Seko-Nakamura B.S. Hideaki Kato M.D. Ph.D. Sanae Kanno Ph.D. Jun Monma-Otaki B.S. Yasuhiro Aoki M.D. Ph.D. 《Journal of forensic sciences》2020,65(3):1004-1008
A 55-year-old man complained of sudden onset of severe neck pain. This was followed by prompt loss of consciousness and death. Autopsy revealed rupture of a saccular aneurysm, which was considered to have resulted from enlargement of the remaining ductal tissue, and was located on the medial aspect of the uppermost portion of the descending aorta. Dense blood extravasation was noted in the posterior mediastinum and extending to the strap muscles of the neck and larynx. Histological examination of the rupture site revealed disappearance of the medial elastic fibers and thickened intima covered with dense fibrous tissue. Spontaneous ductus arteriosus aneurysm in adults is a rare finding, but widespread use of imaging technologies has revealed that it develops more frequently than previously recognized. Fatal complications may occur even when the aneurysm is relatively small. Therefore, pathologists should be aware of this aneurysm as a potential cause of sudden death. 相似文献
220.
Charlotte Murphy Ph.D. June Kenna M.Sc. Lorna Flanagan Ph.D. Marce Lee Gorman B.Sc. Clara Boland Ph.D. Jennifer Ryan Ph.D. 《Journal of forensic sciences》2020,65(2):399-405
This study is the first to examine the background level of male DNA on underpants worn by females in the absence of sexual contact. Here, we examined 103 samples from the inside front of underpants from 85 female volunteers. Samples were examined for the presence of male DNA using NGM SElect and PowerPlex Y23 kits. Only five samples gave a “complete” Y-STR profile, even though 83.5% of our volunteers cohabited with a male. In all cases where a partner reference sample was available, the Y-STR profile matched the cohabiting partner. We have demonstrated that a Y-STR profile is not expected on the inside front of underpants worn by females after social contact alone. The results of this study are informative for evaluating the significance of a Y-STR profile on underpants in cases of alleged sexual assault. 相似文献