Tracking phenomenon, to put it plainly, is the phenomenon to form the carbonized electrical track and lose insulation in the part with potential difference on the surface of insulating materials. Tracking resistance means the difficulty occuring the tracking phenomenon of the organic insulation materials. Studies on the tracking phenomenon and the method of evaluating tracking resistance has been often reported on so far. But, there are only a few comprehensive researches and commentaries which include tracking phenomenon and the fire which occurs by the tracking phenomenon. Hence, I decided to explain tracking phenomenon of the organic insulating materials and the phenomenon that developed concerning the fire which develops and is called, tracking fire. Tracking phenomenon is discussed first. Next, cases of tracking fire in electric wiring and the wiring utensil and the studies on the cause of tracking fire are explained. Furthermore, prevention of tracking fire and future problems are also discussed.

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  This study demonstrates the causes and the prevention measure of the non-specific adherence phenomenon observed in the mixed cell agglutination reaction (MCAR) method using monoclonal antibodies for ABO blood grouping from various kinds of forensic samples. The phenomenon could be suppressed by the addition of both a milk protein (6% Block-Ace) and a detergent (0.3% Tween 20) into the antibody reagents, so that the causes of the phenomenon were likely to be both the electric charge potential effect and the physical absorption of the monoclonal antibodies. In this modified MCAR method, the operation time could be shortened to be about 2/3 of that of the conventional method.

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  This paper presents a study of the intra-individual variation of pubic hairs. Seventy pubic hairs were pulled from seven sites around the outer genital area of each of five Japanese males; sixty were obtained from six sites on each of four Japanese females, and fifty from six sites on one additional Japanese female. These hairs were examined with respect to twenty-two morphological characteristics. These morphological data were studied in relation to each site and analyzed by the statistical method of cluster analysis.
  It appeared that a pubic hair's length, luster, diameter, medullary index, disease and scale damage bore some relation to the site from which it was obtained. Dendrograms produced through the cluster analysis showed a hierarchy of similarities among all pairs of pubic hairs. Similar hairs were placed together into several large or small groups within the same person. Some groups contained pubic hairs from many sites, whereas others were almost exclusively from only one site. This means that some sites have different characteristics from other sites. Pubic hairs obtained from the penis area, scrotum and labium majus area showed greater dissimilarity than other sites within the same person.
  Therefore, in forensic hair comparison, known pubic hair samples should be obtained from many different sites. For males, at least thirty-five pubic hairs should be collected from seven sites (center, left and right abdomen; upper, left and right area surrounding the penis; and scrotum). For females, at least thirty pubic hairs should be collected from six sites (center, left and right abdomen; mons pubis; left and right labium majus).

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  For the high sensitive and selective detection of methamphetamine (MA) and amphetamine (AP) in abusers' hair, we examined and analyzed acylated derivatives of MA and AP by high-performance liquid chromatography-electrospray ionization mass spectrometry. MA and AP were derivatized by trifluoroacetic acid anhydride (TFAA) or pentafluoropropionic acid anhydride (PFPA), as the general acylating reagents. Acylated derivatives were stabilized at least one week in methanol (sample solution) and until 4 hours at 40°C in methanol containing aqueous buffer solution (eluent solution). In both cases of derivatizaton by treatment with TFAA or PFPA, the calibration curves were linear up to at least 200 ng for MA and AP, and the detection limits were 10 pg for MA and 100 pg for AP, respectively, in the selected ion monitoring mode. This method could be successfully applied to the MA abusers' hair samples.

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  The pretreatment method using solid phase extraction (SPE) was investigated for the determination of nerve gas hydrolysis products by gas chromatography-mass spectrometry after tert.-butyldimethylsilyl (TBDMS) derivatization. Various pretreatment conditions using six SPE cartridges [three strong anion exchanger (SAX), one weak anion exchanger, one reversed phase and one mixed mode] were examined for the clean-up of methylphosphonic acid (MPA), ethyl-, isopropyl- and pinacolylmethylphosphonic acid (EMPA, IMPA and PMPA), with regard to recovery from aqueous solution. Within them, optimized pretreatment method using a Bond Elut SAX cartridge containing 500 mg solid phase of fluoride form was established. After sample loading the cartridge was washed with water and retained methylphosphonates were eluted from the cartridge with 5 ml of 3% (v/v) ammonia in methanol. The established method was applied to the pretreatment of various kinds of aqueous samples such as aqueous soil extract, sea water and beverages, and the dramatically improved yields of TBDMS derivatives were obtained, compared with those without SPE pretreatment.

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  We describe a new procedure for the multiplex PCR amplification of the three short tandem repeat (STR) loci; TH01, CSF1PO and TPOX with small amplicon lengths (the Small TCT Multiplex). The accuracy of the Small TCT Multiplex was verified by typing 100 Japanese samples that had been previously typed using an AmpFlSTR Green I PCR amplification kit (Green I Kit). The results using the Small TCT Multiplex were consistent with those obtained by the Green I Kit. STR typing using the Small TCT Multiplex was examined from 36 bloodstain samples that had been left for 1 to 25 years at room temperature and compared to that using the Green I Kit. The Small TCT Multiplex was superior to the Green I Kit for STR typing especially in the case of bloodstain samples that had aged for more than 8 years.

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  The reliability of the morphometric matching method for identifying the blurred images of Caucasian faces was examined experimentally using a computer-assisted facial image identification system. For evaluating the match of the 3D and 2D facial images in the same person (a match), the 3D facial image obtained from 10 subjects was compared to the 2D oblique facial image of the same subject ten times, yielding 100 superimpositions. In the case of different persons (non-matching), the 3D facial images of 10 subjects were each compared to the 2D facial images of other 9 subjects, yielding 90 superimpositions. As a matching criterion, the sum of the values of the average perpendicular difference of the facial outlines and the average point-to-point difference between the corresponding landmarks was used (abbr.: average difference).
  The range of the average difference was 3.6-6.3 mm for the matching person and 5.8-15.3 mm for non-matching persons, respectively. The average difference and percentage error at the FP/FN crossover point were 6.0 mm and 3.2 percent. In this experiment, it was concluded that the morphometric matching method would be applicable to the identification of blurred images of Caucasian faces.

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  Two methods for developing latent fingerprints were examined by use of ninhydrin-acetic acid solution and spray gun.
  In one method, latent fingerprints were developed without heating by ninhydrin- acetic acid solution which contains 10 vol% of acetic acid and 90% of ninhydrin solution. The solution was brushed on paper, then it was enclosed in a plastic bag after volatilization of the solvent. Fingerprints were developed within 30 minutes without heating. This method was found to be useful for the development of latent fingerprints where heating devices such as an iron could not be used.
  In another method, latent fingerprints were developed by spraying gold powder on objects with a portable gas cylinder. Gold powder is the alloy of copper and zinc. Clear fingerprints were obtained because a brush was not required to develop them. This spray gun method could be applicable to all objects on which latent fingerprints were developed by the usual powder method, and was especially effective on oil-prints.

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