A validation study was performed for the AmpFlSTR Yfiler PCR Amplification Kit (the Yfiler kit) to evaluate its potential applicability to Y-STR analysis in forensic casework. The optimal DNA input for PCR amplification was approximately 1 ng of male DNA. A marker-specific stutter ratio to filter stutter peaks higher than that defined by the kit manufacturer has been adopted for some markers to more readily and efficiently type Japanese male samples. No non-specific amplification was observed using 2000 ng female DNA as the PCR template. A full or partial DNA profile was detected from DNA mixture samples containing 1 ng of male DNA and 2000 ng of female DNA. From a mixture of two male DNA samples, all alleles possessed by the minor DNA contributor were detected when DNA derived from the minor contributor was present at 20% of the total DNA and above. Several loci were amplified when analyzing 23-year-old bloodstain samples derived from male individuals. Since they had not yet been defined by the kit manufacturer, we sequenced new alleles observed in Japanese males to assign accurate allele names. Analyses were also carried out of unusual alleles (an allele with poor amplification at DYS390 and apparent null alleles at DYS437 and DYS448) we observed in Japanese males. It is thought important that forensic biologists are aware of new and unusual alleles for DNA profile interpretation. Our validation study indicated the usefulness of the Yfiler kit for analyzing forensic biological samples containing male DNA.

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  Structures of methylenedioxymethamphetamine (MDMA) and methylenedioxyamphetamine (MDA) are very similar to methamphetamine (MA) and amphetamine (AP), respectively. Immunoassay is one of useful methods detecting drugs. We have designed to prepare the antibody for recognizing MDMA and MDA. MDA was conjugated with bovine serum albumin (BSA) by glutaraldehyde method. Rabbits were immunized with MDA-BSA to obtain anti-MDA antibody and IgG fraction from the antiserum was used as an antibody. The cross-reactivity of the antibody was tested by an enzyme-linked immunosorbent assay (ELISA). MDMA showed higher reactivity to the antibody than MDA probably due to similar structures with methylenedioxy moiety. On the other hands, methamphetamine and amphetamine had low cross-reactivity to this antibody. The range of MDMA measurable by ELISA was 0.01-1 μg/well. MDMA in urine could be determined in the range of 0.2 to 20 μg/ml by ELISA using the antibody.

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  The relationship between serial rapist type and the time interval from the first to the second crime was investigated in Study 1. A Bayesian Network (BN) model, included rapists' type derived in Study 1 and the time interval from the first to the second crime, was constructed to predict the time interval till the second crime, and this model was tested in Study 2.
  In Study 1, 147 serial rapists were classified according to the severity of the rapists' criminality by using categorical principal components analysis (CatPCA). Results indicated that the interval from the first to the second crime for rapists with a low severity of the criminality (mean 158.0 days) was longer than that for rapists with a high severity of the criminality (mean 82.1 days). In Study 2, A BN model was constructed from the following variables: rapists' characteristic derived in Study 1 (the severity of the criminality), time interval from the first to the second crime, as well as criminal behaviors. The model was tested by using new data, 20 serial rapists committed, as virtual cases. The results of model estimation indicated that the accuracy of predicting the time interval from the first to the second crime, either within 42 days or later, was 80.0%. In detail, if the model predicted that a rapist would commit the second crime in less than 42 days, the accuracy of the prediction was 75.0%, whereas if the model predicted that a rapist would commit the second crime in over 42 days, the accuracy of the prediction was 87.5%.

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  Ultraviolet (UV) light at a wavelength of 254 nm has been used in Japan to detect latent fingerprints. However, the degradation of DNA at 254 nm UV has become a problem for short tandem repeat (STR) typing. In this study, 306 nm UV light that gives a relatively sharp fingerprint image was selected as a new light source for our imaging instrument, and its effect on STR typing was compared to that of the 254 nm UV light. Twenty microliters of saliva and 3 μl of blood were dried on glass slides and irradiated from 5-20 cm with 306 nm or 254 nm UV light for 0.5-30 min. DNA extracted from the UV-irradiated samples was quantified using real-time PCR assay and STR typing was performed. Both wavelengths reduced the amounts of DNA, as irradiated at the shorter distance or for the longer time. However, the reduction of the amount of DNA was less under the 306 nm UV light than the 254 nm. When the 306 nm UV light was irradiated from 5 cm, full STR profiles were obtained from the saliva and blood samples within 10 and 3 min, respectively. In addition, when it was irradiated from 20 cm, full STR profiles were obtained from all the samples in spite of irradiation for 30 min. It was indicated that the 306 nm UV light could be useful as a new light source. However, the use of the 306 nm UV light at a short distance or for a long time should be avoided as much as possible for STR typing.

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  The microscopic colors of head hair were compared using numerical values provided by image analysis of microscopic digital images of hair.
  In the morphological examination of hair, color is considered to be one of the most important characteristics. In visual observation of hair color, macroscopic and microscopic observation have been carried out. “Dark brown” and “brown” are used as basic colors for the indication of the hair color. In the microscopic observation, it is common to perform more detailed observations of lightness, hue and color changes along the hair shaft. Some mastery of skills is necessary for visual inspection of hair color. Therefore, we examined a measurement method that takes hair color as digital data and an indication method that was suitable to compare hair colors.
  By always checking the luminance of the background in the finder of a digital camera, it became possible to acquire hair images in a constant condition. The measurement of color was enabled with high reproducibility by arranging the measurement area to the appropriate position on images of individual hairs.
  It was suggested that it was suitable to use the CIELAB color system to specify hair color. On the a^*-b^* diagram, the color of each hair and the range of lightness and reddish tinge of control hairs are shown as a coordinate point and a 95% probability ellipse, respectively, so that expressions like “light brown” or “reddish black brown” can be grasped graphically.
  We evaluated a discrimination of the newly devised inspection method by calculating the exclusion ratio from the data of other persons in a personal control color domain (95% probability ellipse) using 254 head hairs collected from ten persons as samples. As a result, a high discrimination was shown depending on the control subject or on a combination of subjects to compare.

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  Soil is one of the most important physical evidence in criminal investigations, which provides useful information regarding with the relations between suspects, victims and crime scenes. Forensic soil samples are conventionally discriminated based on physical properties, such as color and mineral examinations. It is considered that molecular analysis of DNA of soil bacteria can contribute to the criminal investigation substantially, because improvement of discrimination ability of soil will be achieved by addition of biological analysis. This report describes the application of molecular analysis, which is used for discrimination of pathogens in epidemiological investigations, to forensic soil samples. Samples were taken from three sites (A, B and C), and sites B and C, which were 300 m apart, were located about 42 km from site A. Discrimination of soil samples by color and X-ray diffraction analyses were difficult. Then, Bacillus cereus was isolated from the small amount of soil samples which were as little as the lowest quantity required by the conventional method, and discriminated by variable-number tandem repeat (VNTR). The result showed that two VNTR types isolated from A were not included among isolates from B and C even 2 years later. These results suggested that the VNTR analysis using Bacillus cereus might be useful for the discrimination of forensic soil sample analysis. However, Bacillus cereus isolate shows a diversity even isolated from the same soil, therefore further data collection is required to evaluate this method for forensic soil identification.

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  Simultaneous analytical methods for 33 pyrethroids by thin layer chromatography (TLC), gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) have been developed. The detection limits of the pyrethroids were 1 μg or less by TLC, 10-100 pg by GC/MS (SIM mode) and 5-200 pg by LC/MS (SIM mode, except for transfluthrin (2 ng)). The proposed methods were applicable to the analysis of the pyrethroids mixed into drinks and foods.

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  In this study, hardened cement paste prepared from an identical Portland cement under environments with various temperatures and humidity were investigated in order to clarify environmental influences on the hardened cement in forensic science. Twelve cement pastes prepared using an identical Portland cement were set as samples at four places such as the indoors, the outdoors, an oven and a freezer. Hardening reaction processes of cement for eight weeks after the preparation were measured by Raman spectroscopy and X-ray diffraction. The reactions of samples at the indoors and the outdoors progressed until the stage of the reaction producing calcium carbonate (calcite). The reaction of samples at an oven progressed only until the early stage producing ettringite. Samples at a freezer showed no reactions. These differences were mainly caused by the stay time of water around the cement. In the hardening reaction processes of cement paste, water is an important element for progress of hardening reaction of cement paste. The result of this study showed that a variety of hardened cement pastes were observed even if the cement pastes were prepared from an identical Portland cement and water. This result was caused by differences of the environment with various temperature and humidity around cement pastes. This study is useful for more detailed identification of hardened cement paste in forensic science.

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  Low concentration of volatile organic components (VOC) usually need to be condensed before analyzing them by using gas chromatography (GC). NeedlEx^TM is a needle for condensing VOC. Gas components are adsorbed and condensed efficiently while passing through the adsorbents in the needle. This paper describes the results of analysis of tear gas agents or chloropicrin by using NeedlEx^TM. Allyl isothiocyanate (AITC), Chloroacetophenone (CN), o-Chlorobenzylidene malononitrile (CS), α-Brombenzyl cyanide (CA) or Chloropicrine (CP) in 10 L Tedler^® bag were condensed with NeedlEx^TM and analyzed by GC. NeedlEx^TM had a tendency to condense the components having lower boiling point easily than those having a higher boiling point.

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