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81.
The onus of proof in criminal cases is beyond any reasonable doubt, and the issue on the lack of complete internal validation data can be manipulated when it comes to justifying the validity and reliability of the X-chromosomal short tandem repeats analysis for court representation. Therefore, this research evaluated the efficiency of the optimized 60% reduced volumes for polymerase chain reaction (PCR) amplification using the Qiagen Investigator® Argus X-12 QS Kit, as well as the capillary electrophoresis (CE) sample preparation for blood samples on Flinder's Technology Associates (FTA) cards. Good-quality DNA profile (3000–12,000 RFU) from the purified blood sample on FTA card (1.2 mm) were obtained using the optimized PCR (10.0 μL of PCR reaction volume and 21 cycles) and CE (9.0 μL Hi-Di™ Formamide and 0.3 μL DNA Size Standard 550 [BTO] and 27 s injection time) conditions. The analytical and stochastic thresholds were 100 and 200 RFU, respectively. Hence, the internal validation data supported the use of the optimized 60% reduced PCR amplification reaction volume of the Qiagen Investigator® Argus X-12 QS Kit as well as the CE sample preparation for producing reliable DNA profiles that comply with the quality assurance standards for forensic DNA testing laboratories, while optimizing the analytical cost.  相似文献   
82.
The storage and use of explosives is regulated at the state and federal level, with a particular focus on physical security and rigorous accounting of the explosive inventory. For those working with explosives for the training and testing of explosive-detecting canines, cross-contamination is an important concern. Hence, explosives intended for use with canine teams must be placed into secondary storage containers that are new, clean, and airtight. A variety of containers meet these requirements and include screw-top glass jars (e.g., mason jars). However, an additional need from the explosive-detecting canine community is secondary containers that can also be used as training aids whereby the volatiles emitted by explosives are emitted in a predictable and stable manner. Currently, a generally accepted method for the storage of explosives and controlled emission of explosive vapor for canine detection does not exist. Ideally, such containers should allow odor to escape from the training aid but block external contaminates such as particulates or other volatiles. One method in use places the explosive inside a permeable cotton bag when in use for training and then stores the cotton bag inside an impermeable nylon bag for long-term storage. This paper describes the testing of an odor permeable membrane device (OPMD) as a new way to store and deploy training aids. We measured the evaporation rate and flux of various liquid explosives and volatile compounds that have been identified in the headspace of actual explosives. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Explosives were stored individually using traditional storage bags or inside an OPMD at two locations, one of which actively used the training aids. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and Gas Chromatography–Mass Spectrometry (GC–MS) with Solid-Phase Microextraction (SPME). FTIR analyses showed no signs of degradation. GC–MS identified cross-contamination from ethylene glycol dinitrate (EGDN) and/or 2,3-dimethyl-2,3-dinitrobutane (DMNB) across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and that were in active use by canine teams.  相似文献   
83.
Recently, digital forensics has become increasingly important as it is used by investigation agencies, corporate, and private sector. To supplement the limitations of evidence capacity and be recognized in court, it is essential to establish an environment that ensures the integrity of the entire process ranging from collecting and analyzing to submitting digital evidence to court. In this study, common elements were extracted by comparing and analyzing ISO/IEC 17025, 27001 standards and Interpol and Council of Europe (CoE) guidelines to derive the necessary components for building a digital forensic laboratory. Subsequently, based on 21 digital forensic experts in the field, Delphi survey and verifications were conducted in three rounds. As a result, 40 components from seven areas were derived. The research results are based on the establishment, operation, management, and authentication of a digital forensics laboratory suitable for the domestic environment, with added credibility through collection of the opinions of 21 experts in the field of digital forensics in Korea. This study can be referred to in establishing digital forensic laboratories in national, public, and private digital forensic organizations as well as for employing as competency measurement criteria in courts to evaluate the reliability of the analysis results.  相似文献   
84.
This work presents a data survey regarding the qualitative chemical analysis of drugs seized by the Police in the state of Minas Gerais between July 2017 and June 2022, including an evaluation of labeling of 265 samples of anabolic androgenic steroids (AAS) seized in 2020. The Active Pharmaceutical Ingredients (API) present in the samples were identified through chemical analysis and classified by system Anatomical Therapeutic Chemical (ATC) methods. Analysis of the labeling information for 265 samples of AAS followed the guidance of legislation RDC 71 (2009) from ANVISA. For this study 6355 seized pharmaceuticals underwent qualitative chemical analysis that corresponded to 7739 APIs successfully identified and classified. Among the components studied AAS, psychostimulants, anesthetics, and analgesics were the most commonly examined. AAS seized and tested increased by over 100% and for the majority of the samples analyzed were found to not match the labeling on the packaging. In the meantime, anti-obesity drugs presented a prominent increase of 400% from 2020/1 to 2021/2, during covid-19 quarantine. Seized pharmaceuticals and tests can support information in the planning of public health and safety policies.  相似文献   
85.
Human hairs are one of the most commonly encountered items of trace evidence. Currently, conventional methods for hair analysis include microscopic comparison and DNA analysis (nuclear and mitochondrial). Each approach has its own drawbacks. Hair proteins are stable and offer an alternative to DNA testing, as demonstrated with proteomics for distinguishing humans. However, proteomics is complicated and requires identifying peptides to remain intact following harsh sample preparation methods. Alternatively, the actual amino acid content of a hair sample may also offer important identifying information and actually requires proteins and peptides to be broken down completely rather than remaining intact. This study evaluated the discriminating power of using hair amino acid ratios to differentiate hair samples from 10 unrelated individuals with dark colored hair. Hair proteins were digested, derivatized, and analyzed using gas chromatography–mass spectrometry. Amino acid ratios were calculated for each individual and comparisons using ANOVA and post-hoc pairwise t-test with Bonferroni correction were made with amino acid ratios for individuals. Overall, out of the 45 possible pairwise comparisons between all hair samples, 38 (84%) were differentiable. Out of the 36 possible pairwise comparisons between brown haired individuals, 32 (89%) were considered differentiable using univariate statistics. Multivariate statistics were also attempted but, overall, univariate models were sufficient for exclusionary purposes. These results indicate that amino acid ratio analysis can potentially be used as an exclusionary method using hair if DNA analysis cannot be performed, or to corroborate conclusions made following microscopic analysis.  相似文献   
86.
Illicit fentanyl has flooded the United States' drug market, increasing the risk of overdose and poisonings throughout the general population and accidental exposure among law enforcement officers confiscating the increasing number of seizures. Fentanyl test strips (FTS) are used to obtain presumptive information about the presence of fentanyl in a suspected sample. However, their adoption by law enforcement personnel and seized-drug analysts has been limited because most products are advertised for urine testing, not for assays using water solutions. This study presents an evaluation of four commercial FTS: Rapid Response from BTNX, Inc.; T-Dip Fentanyl (FTY) Urine Dip Cards obtained from Amazon.com ; Premier BioDip FYL10 from Premier Biotech Inc.; and MobileDetect Fentanyl strips from DetectaChem, Inc. Performance characteristics curves were used to compare the products' sensitivity, showing that all can reliably detect fentanyl in aqueous solutions at concentrations below 1 μg/mL, with some of the tests able to reliably detect the drug at 200 ng/mL. A stability study demonstrates the performance of all four FTS brands was only slightly affected after 30 days of storage at two extreme environmental conditions. Fentanyl-related substances are also evaluated using the Rapid Response FTS, which showed high cross-reactivity with para-fluorofentanyl and acetylfentanyl, but lower with ortho-chlorofentanyl, carfentanil, and 4-ANPP. Users should be aware that FTS may give false-negative results even when potentially dangerous levels of carfentanil are present. When testing other common drugs, adulterants, and diluents frequently encountered in seized tablets, concentration-dependent results were obtained and multiple instances of false positives were recorded.  相似文献   
87.
2007年6月,美韩双方签署了《美韩自由贸易协定》。美韩之间为什么要签署该协定?该协定对两国国内分别产生了哪些影响?该协定为何至今没能获得美国国会的通过?针对上述问题,本文结合美国贸易政策理论,从体系、国家和社会三个层面对其进行了分析。《美韩自由贸易协定》的签署及其实施,在体系层面上将会为双方带来经济、政治和战略上的多重收益,而在社会层面上却产生了不同的反应。尽管由于国内经济困难和利益集团的掣制使得协定的通过还面临不小的阻力,但基于协定所蕴含的重要价值和两国政府对此认识的高度一致,协定获得通过只是时间上的问题。  相似文献   
88.
东亚-北美经济失衡与再平衡分析   总被引:1,自引:0,他引:1  
本文从国别结构和产品结构分析了20世纪90年代以来东亚—北美经济失衡的变化,认为美国贸易逆差不断扩大是其对外产业转移的结果,东亚地区贸易顺差与日俱增是其承接产业转移的结果。其中,东亚内部再次产业转移导致中国顺差迅速膨胀。为了实现东亚—北美经济再平衡,美国需要采取一些措施扩大出口,控制过度的信贷消费,并对美元采取更加负责的政策;东亚地区需要努力实现由外需驱动型向内需驱动型增长方式的转变,加快产业调整与升级,并把产业链向其他地区延伸。  相似文献   
89.
This article revisits the balancing act between independence and accountability at the European Central Bank (ECB). It contrasts procedural and substantive concepts of accountability, and challenges the mainstream idea that independence and accountability can be reconciled through narrow mandates, the indiscriminate increase of transparency, the creation of multiple channels of accountability, and the active use of judicial review. These assumptions form the pillars of a procedural type of accountability that promises to resolve the independence/accountability dilemma but fails to do so in practice. The article brings evidence to show how ECB accountability has become a complex administrative exercise that focuses on the procedural steps leading up to monetary and supervisory decisions while simultaneously limiting substantive accountability. The failure to acknowledge the trade‐off between independence and accountability (said to be ‘two sides of the same coin’) has resulted in a tendency to privilege the former over the latter.  相似文献   
90.
Extreme fragmentation can complicate the inventory of human skeletal remains. In such cases, skeletal mass can provide information regarding skeleton completeness and the minimum number of individuals. For that purpose, several references for skeletal mass can be used to establish comparisons and draw inferences regarding those parameters. However, little is known about the feasibility of establishing comparisons between inherently different materials, as is the case of curated reference skeletal collections and human remains recovered from forensic and archaeological settings. The objective of this paper was to investigate the effect of inhumation, weather and heat exposure on the skeletal mass of two different bone types. This was investigated on a sample of 30 human bone fragments (14 trabecular bones and 16 compact bones) that was experimentally buried for two years after being submitted to one of four different heat treatments (left unburned; 500?°C; 900?°C; 1000?°C). Bones were exhumed periodically to assess time-related mass variation. Skeletal mass varied substantially, decreasing and increasing in accordance to the interchanging dry and wet seasons. However, trends were not the same for the two bone types and the four temperature thresholds. The reason for this appears to be related to water absorption and to the differential heat-induced changes in bone microporosity, volume, and composition. Our results suggest that mass comparisons against published references should be performed only after the skeletal remains have been preemptively dried from exogenous water.  相似文献   
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