• Title/Summary/Keyword: forensic science

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Mixture of dimethylaminobenzaldehyde and cyanoacrylate to develop fingerprints with fluorescence: a preliminary test

  • Lee, Wonyoung;An, Jaeyoung;Yu, Jeseol
    • Analytical Science and Technology
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    • v.35 no.1
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    • pp.1-7
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    • 2022
  • This study suggests a new one-step fluorescent cyanoacylate-fuming method for developing fingerprints by using a CAB mixed with dimethylaminobenzalde (DMAB) and cyanoacylate (CA) in a specific ratio. CAB is prepared by mixing 2.5 % (w/w) DMAB with CA and fumigated at 180 ℃. Under these conditions, developing fingerprints showed the best results. The fuming method using CAB develops latent fingerprints into fluorescence and has a higher sensitivity than CA, and it showed comparable or better contrast to existing fluorescence enhancement methods. It was also applicable on a variety of non-porous surfaces that can be encountered at ordinary times. This method is more useful than conventional fluorescent dyeing methods in that it minimizes damage to fingerprints or samples, makes it easy to manufacture, saves time, and can use existing current equipment as it is.

Cyanide Poisoning Deaths Detected at the National Forensic Service Headquarters in Seoul of Korea: A Six Year Survey (2005~2010)

  • Lee, Sang-Ki;Rhee, Jong-Sook;Yum, Hye-Sun
    • Toxicological Research
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    • v.28 no.3
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    • pp.195-199
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    • 2012
  • The records of 255 cyanide poisoning deaths obtained from National Forensic Service (NFS) headquarters, located in Seoul of Korea, from 2005 to 2010 were retrospectively reviewed. The mean age was $41.88{\pm}13.09$ and range was 6~80 years (unknown in seven cases). The number of deaths of males and females were 200 and 53, respectively (unknown in two cases). The largest number of cases occurred in people aged 40-49 years (81 cases, 31.8%), followed by the age groups 30~39 years (51 cases, 20%), 50~59 years (44 cases, 17.2%) and 20~29 years (43 cases, 16.9%). The total number of deaths among other age groups (below 10, 10~19, 60~69, 70~79, over 80 years and unknown) were 36, representing only 14.1%. Of all cyanide poisoning deaths, 97.3% were due to suicide, and 14.5% of the total number who died received medical treatment. The most frequent site for ingestion was the person's own residence (120 cases, 47.1%) and the route of administration was mainly oral (252, 98.8%). From the total of 255 cyanide poisoning cases, white powders were submitted for analysis in 92 cases. Potassium cyanide and sodium cyanide occupied 51 and 41 cases, respectively. This study showed that poisoning deaths due to cyanide are one of the continuously reported public health problems in Korea. Enforcement of regulations and safety education to prevent cyanide poisoning should be carried out by the government.

Simulation of Indoor Shooting Range Fire in Busan by Using FDS (FDS를 이용한 부산 실내사격장 화재 시뮬레이션)

  • Cho, Young-Jin;Seo, Young-Il;Moon, Byung-Sun;Kim, Sung-Jin;Jeon, Woo-Jeong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.143-146
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    • 2011
  • 2009년 11월 14일 발생한 부산 실내사격장 화재와 관련하여 조사내용을 토대로 화재 시뮬레이션용 전선유체역학 모델인 FDS를 이용하여 재현하였으며, 시뮬레이션 결과와 화재당시 녹화된 CCTV 영상을 비교하였다. 2층 발사실에서 시작된 화재는 급격히 연소가 진행되어 약 3초 후에 휴게실로 확산되며, 약 7초 후에는 계단 및 1층 홀을 지나 사람들이 통행하는 인도에까지 연기가 분출되는 것으로 나타났다. 시뮬레이션 결과는 2층 발사실과 휴게실에 녹화된 CCTV 영상 및 1층 홀 옆의 귀금속가게에 녹화된 CCTV 영상과 거의 일치하였다.

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Effects of Forensic Science Program on Scientific Creative Problem-Solving Abilities of Gifted Students in Elementary School (과학수사 프로그램이 초등 영재의 과학 창의적 문제해결력에 미치는 효과)

  • Kang, A-Rah;Lee, Kil-Jae
    • Journal of Korean Elementary Science Education
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    • v.34 no.3
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    • pp.265-275
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    • 2015
  • The purpose of this study was to develop forensic science program for the improvement of scientific creative problem-solving abilities in gifted elementary-school students. A program that consists of six sessions (18 hours) is developed in accordance with the CPS model, which has been already proven effective for the improvement of creative problem-solving abilities. This program was applied to sixth-grade 18 gifted students in an elementary school in Gyeonggi province. Examinations of scientific creative problem-solving abilities were performed before and after applying the program in order to determine its effect on gifted elementary students. A qualitative analysis of students' activity sheets, peer assessment and teacher's class journal was made in order to examine the process of improvement of students' scientific creative problem-solving abilities. The results of this study are as follows: First, forensic science program to enhance the scientific creative problem-solving abilities of gifted students was developed. Second, forensic science program is significantly effective in the improvement of scientific creative problem-solving abilities of gifted children of elementary school (p<.05). Third, in early stage of the class, a student, who showed the highest range of change in pre and post tests, revealed the trend of responding in a short answer type. In the late stage of the class, he revealed the capability of producing various creative ideas promptly. On the other hand, students belonging to the upper group of both pre and post test revealed the improvement of divergent thinking skills such as fluency, flexibility, and originality. Fourth, after class, the students responded that the forensic science program developed in this study intrigued the interests and curiosities, and helped them break away from fixed ideas.

Enhancement of bloodstain on the dark or multi-colored surfaces by using the acidic hydrogen peroxide (Acidic hydrogen peroxide를 이용한 어둡거나 다양한 색상의 표면에 부착된 혈흔의 증강)

  • Sungwook Hong;Wonyoung Lee;Jaeyoung Byeon;Hyunju Shin;Jaeuk Ha
    • Analytical Science and Technology
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    • v.36 no.3
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    • pp.121-127
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    • 2023
  • The detection of blood at a crime scene is an important process for identification and case reconstruction. However, blood may be difficult to observe with the naked eye on dark or multi-colored surfaces. Acidic hydrogen peroxide (AHP) is a recently reported blood enhancement reagent that can enhance blood with high sensitivity by increasing the exposure time of the camera. However, it has never been compared to previously known techniques on dark or multi-colored surfaces. For this purpose, the method of observation/photographing (UV and IR photography), alginate casting, leuco rhodamine 6G (LR6G), and AHP were applied to bloody impression on dark or multi-colored surfaces and the results were compared. As a result, blood treated with AHP had a higher contrast to the surfaces than UV and IR photography, and it was applicable on all surfaces, opposed to alginate casting. In addition, AHP successfully enhanced blood on dark or multi-colored surfaces, similar to LR6G.

Sensitivity study of the Yfiler® PLUS PCR Amplification Kit in forensic casework samples (법과학 현장시료에서 Yfiler® PLUS PCR Amplification Kit의 민감도 연구)

  • Jung, Ju Yeon;Kim, Kyoung Sook;Park, Sun Wha;Lim, Si Keun;Lee, Dong Sub;Lee, Yang Han
    • Analytical Science and Technology
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    • v.29 no.1
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    • pp.43-48
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    • 2016
  • A variety of Y-STR analysis kits have been developed and used in the forensic field. Prior to the forensic application of a new kit, laboratory validation and sensitivity tests are essential processes in selecting suitable alternatives and for assuring that standard operating procedures are followed. In this paper, we have performed a sensitivity study of a new commercial kit, the Yfiler® PLUS PCR Amplification Kit (Yfiler plus kit, released in 2014) by comparing it with the AmpF/STR® YfilerTM PCR Amplification Kit (Yfiler kit, released in 2004). The Yfiler plus kit includes the 17 Y-STR loci of the Yfiler kit and has been supplemented with 10 new Y-STR loci. First, we analyzed the sensitivity difference between the two kits using commercial control DNA 2800M and 007. In addition, we compared the detection rate between the two kits from the 16 selected forensic casework samples of less than 0.5 ng concentrations. The results show that the sensitivity and detection rate of the Yfiler plus kit are higher than the corresponding rates of the Yfiler kit. In addition, we were able to obtain more Y-STR profiles with the use of the new kit. Thus, we suggest that Yfiler plus kit is a more effective forensic tool to detect Y-STR profiles from forensic casework samples of low concentrations.

A Feature Comparison of Modern Digital Forensic Imaging Software (현대 디지털 포렌식 이미징 소프트웨어 도구 특징 비교에 대한 연구)

  • Ham, Jiyoon;James, Joshua I.
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.6
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    • pp.15-20
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    • 2019
  • Fundamental processes in digital forensic investigation - such as disk imaging - were developed when digital investigation was relatively young. As digital forensic processes and procedures matured, these fundamental tools, that are the pillars of the reset of the data processing and analysis phases of an investigation, largely stayed the same. This work is a study of modern digital forensic imaging software tools. Specifically, we will examine the feature sets of modern digital forensic imaging tools, as well as their development and release cycles to understand patterns of fundamental tool development. Based on this survey, we show the weakness in current digital investigation fundamental software development and maintenance over time. We also provide recommendations on how to improve fundamental tools.

Method Development and Validation of Strychnine in Blood by Gas Chromatography/Mass Spectrometry Using Solid Phase Extraction and its Application in Real Specimens (SPE 및 GC/MS에 의한 혈액중 스트리크닌의 분석법 개발 및 검출사례)

  • Rhee, Jongsook;Yum, Hyesun;Moon, Sungmin;Lee, Sangki
    • YAKHAK HOEJI
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    • v.57 no.2
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    • pp.87-94
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    • 2013
  • An analytical methodology based on solid-space extraction (SPE) with with Bond Elut Certify cartridge (Varian, 130 mg) has been developed for the qualification and quantitation of strychnine in blood. After the elution layer was evaporated, the residue was reconstituted with methanol for GC/MS. Internal standard was used 10 mg/l dextromethorphan. Strychnine is a potent central nervous stimulant and convulsant, and an alkaloid found in seeds of Strychnos nux-vomica. It was used therapeutically to improve circulation and muscle tone in oral or intramuscular doses of 0.05~8 mg. The fatal dose of strychnine for humans is 50~100 mg. A man was found dead lying curled up the corner of the large room in a roof house after the fire fighter opened a locked door inside to put out the fire. The postmortem blood and gastric contents were analyzed for toxicological testing. Strychnine and brucine were detected using GC/MS first in gastric contents extracts. The contents of strychnine was 0.083 mg/l in heart blood, 0.088 mg/l in peripheral blood and 4.0 mg/kg in gastric contents, respectively. Method validation was carried out in terms of linearity, accuracy, precision (intraday, interday) in blood. The assay is linear over 0.05~10 mg/l ($r^2$=0.999). Limit of detection (LOD) and limit of quantitation (LOQ) in blood were determined 0.02 mg/l (S/N=3) and 0.07 mg/l (S/N=10), respectively. Accuracy (bias%) of strychnine with 0.1, 1 and 10 mg/l was 12.0% (n=6), 9.3% (n=6) and 6.9% (n=6), respectively. Intraday precision (CV%) of strychnine with, 0.1, 1 and 10 mg/l were 6.4%, 10.4%, 1.2% (n=6), respectively. Interday precision (CV%) of strychnine with 0.1, 1 and 10 mg/l over three days were 24.0%, 18.5%, 13.8% (n=18), respectively. Relative recovery with 0.1, 1 and 10 mg/l (in blood) were 114.9%, 99.3% and 87.4% (n=6), respectively. The described method can be applied in forensic toxicology to determine strychnine in blood samples.