Facial image identification has become important in forensic science because surveillance cameras are popularly used as silent witnesses at potential crime scenes. In general, three methods are used for facial image identification: morphological comparison of facial features, facial image anthropometry and face-to-face superimposition. The most commonly employed method in actual casework is morphological comparison based on the morphological classification of facial components such as facial types, eyebrows, eyes, nose, lips and ears. However, classification for ear morphology has not been developed, except for the ear lobe. The human ear has various anatomical parts, including the helix, antihelix, tragus, antitragus, scaphoid fossa, and ear lobe. The present study was designed to develop a new classification system for the ear.
  Ear images obtained from 164 Japanese adult males (n=94, age range: 24-60) and females (n=70, age range: 20-54) were used for establishing the morphological classification. In general, the features of the ear are very easily influenced by camera angle, which usually make it difficult to compare facial images taken with surveillance cameras to mug shots in actual casework. In our previous study, however, it was suggested that some components of the ear are little affected by camera angles if the scaphoid fossa could be found on the image even though the external acoustic meatus could not be found. Therefore, the morphological characteristics of some components such as the antihelix, tragus, antitragus, scaphoid fossa, and ear lobe were observed in the ear images from all persons, and morphological classification items for those components were established. All data classified according to these items were analyzed to obtain their frequency distribution in each component and to clarify the correlation between morphological characteristics. The results revealed that some morphological characteristics in each component were significantly correlated.
  The present classification system for ear morphology would be useful for facial image identification.

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  The application of inductively coupled plasma mass spectrometry (ICP-MS) in the determination of the concentrations of trace elements in steel wires was investigated for the forensic discrimination of wires with different origins; the discrimination is carried out by comparing elemental compositions. Approximately 5 mg of a chip taken from the wire was accurately weighed and dissolved in a mixture of 100 μl HCl and 100 μl HNO₃ by heating at 80°C for 30 min. Following the addition of 100 μl of 5 μg/ml Y as an internal standard and 200 μl of 7M HCl, the matrix iron in the solution was removed by extraction with 200 μl MIBK. This extraction was repeated twice, and 300 μl of the aqueous phase was heated at 150°C for 1 h after the addition of 250 μl H₂SO₄. This solution was diluted to 25 ml by 1% HNO₃, and then the solution was used to determine the concentrations of Cr, Mn, Ni and Cu by ICP-MS. The measured values of these elements in NIST 16f (Steel Basic Open-Hearth) showed satisfactory good agreement with the certified values with RSDs from 1.0 to 2.1%. A comparison of the concentrations of the four elements determined by using the present method can be carried out to differentiate among the 21 possible pairs that can be formed from 7 wires produced by different manufacturers.

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  As a retardation of fatigue crack propagation occurs under two step loading such as high to low loading, it is difficult to estimate the fatigue life in variable loading conditions. Therefore, the mechanism of retardation was investigated by changing the ratio of two-step loading in aluminum alloys in this paper.
  It is found in this study that acceleration of crack growth following low-to-high load change is not apparent in this investigation, there exists a uniquely-shaped fracture surface with some width (about 50-200 um) right angle to the crack growth direction at the load-change area under high-to-low load change. This area shows some swelling, with no striation but minute and distinct unevenness.
  When R=0 and -1, if maximum load decreases to 80%, crack retardation does not occur even though the crack growth rate falls slightly. When R=0.1, by varying low load in small increments (50%, 45%, 43%, and 40%) the number of cycles of crack retardation were investigated. The varying rate is in proportion to the number of cycles of crack retardation.
  This study proposed a crack growth model wherein the plastic zone formed by tensile stress was compressed by the surrounding elastic zone, and the crack does not open immediately under tensile stress load.

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  Cyanoaclyrate (CA) fuming has commonly been used to detect latent fingerprints and was reported in most cases not to adversely affect short tandem repeat (STR) typing. However, the effect of the CA fuming on DNA extraction efficiency was not reported. In this study, the DNA quantity of CA-fumed samples was measured by real-time PCR assay and STR typing was performed. Twenty microliters of saliva and 3 μl of blood were smeared on glass slides and polyethylene terephthalate (PET) sheets. The samples were treated with (1) CA, (2) CA and ultraviolet light (UV, 254 nm) irradiation, and (3) CA, 7-benzylamino-4-nitrobenz-2-oxa-1,3-diazole (BBD) and Polilight (450 nm) irradiation. The amounts of DNA extracted from the samples were quantified using real-time PCR assay and STR typing was performed. The saliva samples on the glass slides were covered with a large amount of CA, and the average of their DNA concentrations was reduced to 0.43 ng/μl, while that of non-treatment control was 0.75 ng/μl. Similar results were obtained from the saliva samples on the PET sheets. A Double swab technique did not improve the recovery of the DNA quantities. On the other hand, blood samples that were hardly covered with the CA had almost the same DNA quantities as those of the non-treatment control. Concerning the post treatment methods, the UV irradiation drastically reduced the DNA quantities, but the BBD and the Polilight hardly reduced them. Full STR profiles were obtained from all of the saliva and blood samples except for the samples irradiated with the UV. Ten PET bottle samples were fumed with the CA gas as the simulated casework samples, and full STR profiles were obtained from 8 out of 10 samples. In conclusion, DNA quantity of saliva samples was reduced by CA fuming probably due to the covering of a large amount of the CA; however, the CA fuming did not affect STR typing adversely.

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  The blast wave caused by the explosion of the explosive and so on shows the refractive index which is different from that of ambience because the wave is accompanied by the density change of the medium. The Schlieren method is often used as a technique to observe the behavior of fluid using the difference of refractive index. However, it is difficult to apply to outdoor experiments because the method requires arrangements of some optical equipments around the subject. In this study, the visualization of the blast wave in a convenient method from the digital frame images which had been taken by a digital high-speed camera in a past outdoor experiment without any optical equipment was tested. This method was a subtraction of images, and a processed image was produced by difference of gradations between two original frame images before and after the explosion. In a part of the background which resulted in a mottled pattern having minute bright and dark parts, the blast wave was possible to be visualized in every frame image. The main blast wave and reflected blast wave from the ground were observed in the processed images. The equivalent ratio to other conventional explosives was derived from the propagation of the blast wave clarified by the processed images. Consequently, this method can be used for estimation of the power of explosion.

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  In this study, the stability of methamphetamine, bromovalerylurea, acetaminophen and salicylic acid in formalin solution was investigated during 90 days. The stability of these drugs was examined in 4 types of formalin solution (10% and 20% concentration pH adjusted formalin (pH7.4) and each concentration pH unadjusted formalin solution) and at 2 temperature conditions (room temperature and cold storage).
  Methamphetamine was very stable at cold storage in each formalin solution. In contrast, more than 80% of methamphetamine was converted into its N-methyl derivative, dimethylamphetamine in pH adjusted formalin at room temperature at 90 days. Bromovalerylurea was stable only when in pH unadjusted formalin at cold storage. Under the other conditions, bromovalerylurea was decomposed and observed a compound assumed to be the bromovalerylurea-formaldehyde reaction product by LC/MS. The concentration of acetaminophen was decreased gradually under all conditions and a compound assumed to be the acetaminophen-formaldehyde reaction product was detected by LC/MS and GC/MS. When salicylic acid was stored under all conditions, concentrations of salicylic acid did not change.
  Thus, it appears that the stability of drugs varies individually in the presence of formalin and under different conditions (formalin concentration, pH and storage temperature). So, forensic scientists must note when attempting to determine the drugs in the formalin-fixed biological specimens.

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