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To evaluate the important odor components in raw yellowtail, volatiles from each part of stored yellowtail flesh were analyzed using gas chromatography-mass spectrometry (GC–MS) and olfactometry (GC–O). The principal component analysis (PCA) results from GC–MS of 88 volatiles showed that PC1 separated the data into two groups [the dark muscle (DM) long storage] and [the ordinary muscle (OM) + DM no storage + DM short storage]. Eleven compounds, including 2,3-butanedione, in 24 kinds of odors were identified or tentatively estimated using GC–O analysis. The numbers of odors perceived at the maximum split ratio (243) in GC–O analysis were 8 and 12 from OM and DM, respectively, irrespective of storage time. Kovats retention index 1387 (unknown compound, fishy and plastic odor) had the strongest odor in both muscles before and after storage. GC–O analysis showed that DM odors were more intense than those from dorsal OM. Moreover, their intensities increased during storage. Sensory evaluation revealed that DM had a stronger odor than OM throughout the storage period. These findings suggested that odor components, which showed small thresholds, as well as other identified components from DM, such as 2,3-butanedione, contributed to the yellowtail meat odor before and after storage.

The prediction of the nonequilibrium radiative heat flux experienced by a sample return capsule relies on a combined approach of numerical simulation and ground test experiments. This paper presents an analysis of the VUV radiation measurements from heated air mixtures carried out in the High Velocity Shock-Tube (HVST) facility at JAXA Chofu Aerospace Centre. The spectral signatures of atomic lines were analyzed under equilibrium and nonequilibrium conditions. The electron number densities were inferred from hydrogen lines and used as a benchmark to assess the ionization model currently implemented in the in-house solvers.

Owing to the increasing importance of genomic information, obtaining genomic DNA easily from biological specimens has become more and more important. This article proposes an efficient method for obtaining genomic DNA from nail clippings. Nail clippings can be easily obtained, are thermostable and easy to transport, and have low infectivity. The drawback of their use, however, has been the difficulty of extracting genomic material from them. We have overcome this obstacle using the protease solution obtained from Cucumis melo. The keratinolytic activity of the protease solution was 1.78-fold higher than that of proteinase K, which is commonly used to degrade keratin. With the protease solution, three times more DNA was extracted than when proteinase K was used. In order to verify the integrity of the extracted DNA, genotype analysis on 170 subjects was performed by both PCR-RFLP and Real Time PCR. The results of the genotyping showed that the extracted DNA was suitable for genotyping analysis. In conclusion, we have developed an efficient extraction method for using nail clippings as a genome source and a research tool in molecular epidemiology, medical diagnostics, and forensic science.