The importance of scientific evidence in criminal investigation is now increasing, and more and more novel techniques are introduced in forensic science field. So, the court has great difficulty in determining the admissibility of scientific evidence. The situation will get worse after when a big reform of the court will begin in 2009 because citizens not being trained for the judicial judgment will participate in the court. In order to solve this problem the efforts of the court and forensic scientists are needed.

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  The availability of software developed to correct the distortion associated with non-metric cameras was examined using a test chart composed of 63 gridiron dots and two CCD cameras: a commercially available camera as the reference and an actual surveillance camera installed in a bank. The software was designed to calculate distortion parameters such as the radial and tangential distortion coefficients and the principal points. Constant parameter values were obtained when test charts were taken at six positions in the lens field. The average of displacement errors between the 63 dots on the corrected image and those on the presumed ideal image was measured. In the reference camera, a pre-correction error of 1.24 mm decreased to 0.08 mm after correction. In the surveillance camera the error decreased from 7.92 mm to 0.33 mm. The present method was compared with two others: the graph method and the Open CV method. The former uses a distortion graph, which indicates the distortion level (%) at several locations from the center to the radial direction of the lens field. The latter is a free camera calibration software tool, developed by Intel Co. for the calculation of the intrinsic camera parameters of video camera lenses. The present method was associated with smaller error values than either of the other two methods. It is therefore suggested that this method could usefully be applied to distortion correction of facial images taken by surveillance cameras.

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  Recently, forensic test for evidence of sweat and other body fluids has increased. However, no plenary test has been developed for demonstration of the presence of sweat, though preliminary tests using urea or lactic acid as indices are widely used. We established a new method for confirming the presence of sweat by high-performance liquid chromatographic (HPLC) detection of two targets, E-urocanic acid (E-UCA) and L-tyrosine (L-Tyr).
  Six different body fluid stains (sweat, urine, saliva, semen, vaginal fluid and blood) were extracted with distilled water and the extracts were separated by HPLC on a ODS column. The mobile phase was 50 mM phosphate buffer (pH 2.2) and the UV detector was set at 231 nm. The column temperature was maintained at 40°C.
  Two targets were detected in the sweat stains, but E-UCA was not detected in other body fluid stains. These results indicate that the presence of E-UCA is specific for sweat. This method was capable of identifying sweat stains on samples that had been stored for 6 months at room temperature, and should prove very useful for the identification of sweat stains in forensic cases.

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  Soil can be one of the most important physical evidence in a criminal investigation which contributes to prove a linkage between the suspect and the crime scene. In this work, the validity of multiple instrumental analytical techniques for forensic soil identification was studied using 148 soil samples collected from the Tokyo metropolitan area. The samples were characterized by X-ray diffraction (XRD) analysis, X-ray fluorescence (XRF) analysis, magnetic susceptibility determination, scanning electron microscopy with an energy dispersive X-ray spectrometer (SEM-EDS) and high-energy synchrotron radiation X-ray fluorescence (SR-XRF) analysis. It was found that soil samples collected from railway stations and roadside dust showed higher magnetic susceptibilities (≧0.5×10^-4 m³ kg^-1 for 25% of the samples collected ) than those of soil samples collected from rivers, ponds, and lakes (<0.1×10^-4 m³ kg^-1 for 40% of the samples colleted). Microscopic examination of the soil samples revealed three kinds of characteristic spherules: i.e., transparent, white, and black particles. The SEM-EDS analyses of the spherule samples showed the following compositional characteristics. The transparent spherules exhibited two compositional types: Na-Ca-Si-O and Ba-Ti-Si-O types. On the other hand, black ones were either Fe-O or Si-Mg-O types and white ones were either Al-O or Sr-Al-O types. It was concluded that these six types of spherules were found at characteristic points and consequently, they can be used as forensic soil identification.

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  The effect of heating on the refractive index of glass was investigated in order to decide whether the screening of glass fragments by RI measurement could be employed before elemental analysis when a burglar was suspected to enter a house after breaking the windowpane using a burner. Glass fragments (1-2 mm in a maximum diameter) were taken from the bulk of sheet glass samples produced by 3 different manufacturers for the windowpane of buildings. The RI values of these fragments were measured before and after heating by a pyrolyzer. It was found that heating over 670°C caused the decrease in RI values of all glass fragments by more than 0.0002, which corresponds to the defined limit of RI value variation for discriminating glass samples. The reduction of RI was observed after 30 seconds of heating at 764°C and was kept for 7 weeks. Heated and non-heated glass fragments from a same source provided identical RI values after both samples were heated at 900°C for 2 minutes and cooled to room temperature under the same condition. It should be emphasized that the direct comparison of heated glass fragments with non-heated reference glass by RI measurement could result in a wrong conclusion. The screening of glass fragments by the comparison of RI must be performed after the re-heating of heated and non-heated glass under the same condition when it was suspected that the examined glass had been subjected to high temperature.

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  A microextraction method using a pipette tip type solid phase extraction (μSPE) device was developed for extraction of illicit drugs in human urine. Three types of pipette tips with monolithic SCX, C18 and C4 were compared with recovery of illicit drugs and metabolites such as methamphetamine, amphetamine, 3,4-methylendioxymethamphetamine, 3,4-methylendioxy-amphetamine, ketamine and norketamine, respectively.
  The recovery was low (<64%) with SCX type pipette tip, however, C18 and C4 type tips were suitable to extract these drugs in high recovery (>86% and >81%, respectively) from 50 μL urine sample. And this extraction procedure was completed in five minutes.
  Therefore, this microextraction method using C18 type μSPE device was useful for rapid and simple extraction of illicit drugs in small volume urine sample.

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  We have reported a new method to detect the geographical origins of unidentified cadavers using BK and JC virus genotyping. Altogether, these two viruses enabled us to determine the geographical origins of more than 70% of unidentified cadavers and to provide much more precise information regarding geographical origin. Recently, we developed a JC virus DNA chip for rapid and simple diagnosis of the geographical origins of unidentified cadavers. The DNA chip takes only half a day to obtain results, whereas the conventional method requires several days. Furthermore, this new technique does not require any special technical knowledge. Herein, we report a newly developed BK virus DNA chip. In addition to the JC virus DNA chip, the BK virus DNA chip may become a powerful tool for the identification of unidentified cadavers.

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  Sixty-one liquid kerosene samples and extracts from seventy-nine fire debris were calculated from multiple correlation coefficients (R) against two kinds of marketing kerosene as reference with a different calculation method of regression analysis by using 16 components that was eluted after n-undecane. Quantitative evaluation for debris of kerosene was performed with the R values. If the sample R value obtained was more than 0.95 using a gas chromatogram, we can judge the sample to be kerosene. For the sample R values from 0.95 to 0.85, additional information was required to judge the samples of kerosene. If the sample R value showed less than 0.85, it can be concluded that it was not kerosene.

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  Enantioselective analysis of methamphetamine (MA) and amphetamine (AP) is necessary in forensic drug analysis. In general, standard materials are required for performing forensic investigation and also for developing new analytical methods. However, l-MA is not commercially available in Japan and only a few reports are available on the enantioselective synthesis of l-MA. We developed a new and convenient method for the synthesis of l-MA using d-norephedrine (d-NE) as a starting material. d-NE was treated with 1,1′-carbonyldiimidazole to produce the corresponding cyclic carbonate, and the product was treated with sodium hydride and iodomethane to form mono-N-methylated amine derivative, which was treated with palladium on activated carbon in hydrogen atmosphere for catalytic reduction. After the addition of aqueous hydrogen chloride (HCl), l-MA was obtained as its HCl salt (total yield 58%).

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  Sildenafil and related compounds, vardenafil, tadalafil and hydroxyhomosildenafil, in dietary supplements were characterized using thin layer chromatography (TLC), infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). TLC with Dragendorff reagent gave a lower detection limit than 1 μg for all 4 compounds. IR spectra of the compounds were so characteristic as to discriminate one from another easily. After TMS derivatization, all the peaks of these compounds appeared and well-separated on the GC/MS chromatograms at a high column temperature (320°C), although hydroxyhomosildenafil was not detected without derivatization. In HPLC and LC/MS analyses, an ODS column with a mobile phase composed of a mixture of 20 mM ammonium acetate (pH 5.0) and methanol (40:60) allowed separation of the 4 compounds. Simple electrospray-ionization mass spectra with only protonated molecules were obtained except for tadalafil, which was cleaved easier than the other compounds, so cone voltage should be lower for tadalafil. Quantitative analysis of the 4 compounds was carried out using HPLC (UV at 230 nm). The lower limit of detection for each compound was 50 ng/ml at a 10-μl injection volume (0.5 ng on the column, S/N>3). A calibration curve was linear in the range of 0.01-1.0 mg/ml for each compound (r²>0.997). Our methods were applied to casework samples (confiscated tablets), and disclosed that those tablets contained varying amounts of sildenafil and/or tadalafil and were counterfeit products.

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  Offender profiling is one of the tools of decision making for criminal investigation. It is a set of techniques to infer characteristics of an unknown offender, such as sex, age bracket, lifestyle, psychological feature, previous crime, inhabited area, from the information which is left at the crime scene.
  In this article, we proposed a tool of decision-making for criminal investigation from the perspective of prediction of an uncertain event by the use of a Bayesian Network (BN). BN is a probability model that describes causal structure of events as chain networks of conditional probability, and is capable to predict the possibility of uncertain events.
  To examine the validity of the constructed model, firstly, we divided previous offenders’ information of the indoor-sex-offence cases into a training data (9,859 cases) and validation data (50 cases). Secondly, we constructed a model from the training data by means of K2 and MDL (minimum description length) as search-algorithm and information criteria, respectively. Finally, the validity of the model was examined by the validation data as virtual cases.
  According to the model, 21 target variables (16 behavioral variables, 2 vehicle variables and 3 victim variables) linked the explanatory variable (employment) directly, and most of these variables related to the employment. The results of the model validity showed that the accuracy of predicting the employment increased 10% higher when the age bracket could be estimated from the testimony of the victim.
  The results indicated that the BN model of the offender profiling would be able to provide valuable information for decision making for crime investigation. To predict characteristics of an unknown offender more accurately, it is crucial to select more appropriate information criteria and develop the search-algorithm, as well as to construct the database from more accurate information.

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  After examining some materials for collecting oil from evidential material at the scene of a fire, we reported that oil clear film (face oil remover) was the most suitable.
  Since oil clear film catches the oil but repels water, we can obtain the oil alone even from evidence that contains water.
  Oil can be extracted from the film using a small amount of solvent and analyzed by GC.
  This time I made some experiments on contemplating the film performance of oil adsorption.
  Each film adsorbed with gasoline, kerosene and diesel oil was extracted at proper time intervals and analyzed with gas chromatograph.
  In this way I measured the decrease of adsorbed oil.
  The film is capable of detecting kerosene up to 1hour after adsorption and diesel oil up to 1 day after adsorption.
  Gasoline is volatile and needs to be contained in the gas barrier plastic bag within 3 minutes after adsorption.
  Oil clear film contains something similar to lubricant oil made from petroleum.
  Thus, in case of collecting oils containing motor oil like a mixed gasoline, we should use oil clear films after degreasing by solvent.

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  Recent high-performance sports shoes sometimes have a sole which made from several materials composed of different properties.
  One of such material is foaming rubber. This is produced by foaming a rubber, cut with a mold, then pasted to a sole.
  As this foaming rubber-contained sole causes conspicuous differences in a process of manufacturing, there is no identical sole even if the shoe is of the same size.
  This intrinsic distinction could be extremely effective in differentiating diversities.

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  A new tracking fluorescent reagent was developed by use of polyacrylate gel, named “Aqua-chase”. Aqua-chase consists of crosslinked polyacrylate polymers such as adhering agents and a water-soluble fluorescent reagent. As the result of walking experiments using shoes with tracking fluorescent reagents on the sole, Aqua-chase adhered on the paved road surface up to six times more than compared with the reagent using vaseline, used generally as an adhering agent. Aqua-chase was found to be a useful tracking fluorescent reagent.

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