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21.
Tetsuya Inagaki Hitoshi Yonenobu Yuuki Asanuma Satoru Tsuchikawa 《Journal of Wood Science》2018,64(4):347-355
Here, we evaluated the application of near-infrared (NIR) spectroscopy for estimating the degradation level of archeological wood samples from the Tohyamago area, the dendrochronological ages of which were also determined. The wood samples were radially cut from three logs obtained from the Tohyamago area. NIR reflectance spectra were measured from the tangential faces of air- and oven-dried wood samples using a Fourier transform NIR spectrophotometer. The second derivative spectra within the wavenumber range of 6400–5200 cm?1, in which the effect of moisture content in wood is suspected to be insignificant, showed a characteristic behavior with age. By comparing the second derivative spectral change in our wood samples with that in wood degraded by aging, thermal treatment, fungal attack, and lightning reported in the literature, we found that the second derivative spectra of wood samples from one log was similar to those of wood degraded by hygro-thermal treatment, whereas those of wood samples from another log was similar to those of wood degraded by brown-rot fungi. The physical and chemical properties of archeological wood were well predicted using a combination of partial least square regression analysis and NIR spectroscopy. 相似文献
22.
We selectively assessed the thermal and hygrothermal treatment times of duplex heat-treated samples from the softwood hinoki cypress (Chamaecyparis obtusa) and the hardwood Japanese zelkova (Zelkova serrata) using near-infrared (NIR) spectroscopy with principal component analysis (PCA) and spectral-kinetic analysis. Wood samples from each species were thermally or hygrothermally treated at 120, 130, 150, and 180 °C, and the second-derivative spectra of these samples in the 6300–5450 cm?1 range, where moisture content has the smallest effect, were then subjected to PCA. The master curve that was calculated by kinetic analysis successfully explained changes in the first principal component (PC1) scores with thermal treatment time for all temperatures. The angles between the PC1 loadings that explained the spectral variation due to thermal and hygrothermal treatment were 79° for hinoki and 80° for zelkova. Thus, calculation of the inner product between the second-derivative spectra of duplex heat-treated wood and a loading vector that explained the spectral variation due to thermal or hygrothermal treatment allowed us to selectively assess the thermal and hygrothermal treatment times. 相似文献
23.
The aim of the present study was to determine whether bovine coronavirus (BCV) has the ability to initiate infection in a human colon carcinoma cell line, Caco‐2, that has been established to spontaneously differentiate after confluence. When Caco‐2 cells were infected with BCV, a titer of 5.5 × 106 plaque‐forming units (p.f.u.)/mL was found in the culture supernatant at 5 days postinfection. Two clones, Caco‐2/CA1 and Caco‐2/CA2, were then isolated by monitoring alkaline phosphatase (ALP) and cell proliferation activities. The ALP activity level of CA1 cells was significantly higher than that of CA2 cells, while the level of cell proliferation activity of CA1 was significantly lower than that of CA2. When CA1 and CA2 cells were infected with BCV at confluence, virus hemagglutination (HA) was detected in the culture supernatant at 5 days postinfection for CA1 cells and at 8 days postinfection for CA2 cells. Thus, BCV propagation was substantially delayed in CA2 cells, suggesting that a cellular factor(s) that appears at the differentiation stage may control BCV propagation. BCV‐susceptible CA1 and CA2 cells showing different levels of ALP activity would be useful for further experiments to elucidate the mechanism of BCV propagation. 相似文献
24.
Kosuke OTAKA Yuuki HIRADATE Norio KOBAYASHI Yoshiki SHIRAKATA Kentaro TANEMURA 《The Journal of reproduction and development》2015,61(5):375-381
During mammalian spermatogenesis, spermatogenic cells undergo mitotic division and are subsequently divided into haploid spermatids by meiotic division, but the dynamics of sex chromosomes during spermatogenesis are unclear in vivo. To gain insight into the distribution of sex chromosomes in the testis, we examined the localization of sex chromosomes before and after meiosis in mouse testis sections. Here, we developed a method of fluorescence in situ hybridization (FISH) using specific probes for the X and Y chromosomes to obtain their positional information in histological testis sections. FISH analysis revealed the sex chromosomal position during spermatogenesis in each stage of seminiferous epithelia and in each spermatogenic cell. In the spermatogonia and leptotene spermatocytes, sex chromosomes were distantly positioned in the cell. In the zygotene and pachytene spermatocytes at prophase I, X and Y chromosomes had a random
distribution. After meiosis, the X and Y spermatids were random in every seminiferous epithelium. We also detected aneuploidy of sex chromosomes in spermatogenic cells using our developed FISH analysis. Our results provide further insight into the distribution of sex chromosomes during spermatogenesis, which could help to elucidate a specific difference between X and Y spermatids and sex chromosome-specific behavior. 相似文献
25.
Takeharu KANEDA Yuuki KIDO Tsuyoshi TAJIMA Norimoto URAKAWA Kazumasa SHIMIZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):15-19
The effects of various
selective phosphodiesterase (PDE) inhibitors on carbachol (CCh)-induced contraction in the
bovine abomasum were investigated. Various selective PDE inhibitors, vinpocetine (type 1),
erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA, type 2), milrinone (type 3), Ro20-1724 (type
4), vardenafil (type 5), BRL-50481 (type 7) and BAY73-6691 (type 9), inhibited CCh-induced
contractions in a concentration-dependent manner. Among the PDE inhibitors, Ro20-1724 and
vardenafil induced more relaxation than the other inhibitors based on the data for the
IC50 or maximum relaxation. In smooth muscle of the bovine abomasum, we
showed the expression of PDE4B, 4C, 4D and 5 by RT-PCR analysis. In the presence of CCh,
Ro20-1724 increased the cAMP content, but not the cGMP content. By contrast, vardenafil
increased the cGMP content, but not the cAMP content. These results suggest that
Ro20-1724-induced relaxation was correlated with cAMP and that vardenafil-induced
relaxation was correlated with cGMP in the bovine abomasum. In conclusion, PDE4 and PDE5
are the enzymes involved in regulation of the relaxation associated with cAMP and cGMP,
respectively, in the bovine abomasum. 相似文献
26.
Nobuhide KIDO Kaori ONO Tomoko OMIYA Yukio OGUCHI Moemi SETOGAWA Yuuki MACHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1651-1653
Oral examination of two guinea pigs revealed that the unilateral incisor was absent. On radiographic examination, the incisor was identified within the nasal cavity in both patients. Under anesthesia in both patients, the skin was incised from the nostril to 1.5 cm proximal, and the premaxilla and part of the maxilla were exposed. The bone was removed using a surgical drill, and the incisor was exposed in the nasal cavity. The root was grasped with forceps and carefully extracted as it was degraded and very fragile. Diagnosis was easy using oral and radiographic examination. In guinea pig patients where an incisor is absent on oral examination, this condition should be considered. 相似文献
27.
Fatty acid analysis of roughscale sole Clidoderma asperrimum flesh lipids was carried out by gas chromatography. An unidentified peak appeared in the chromatogram in the elution region
of ≥C24 fatty acids. After enrichment by solvent partitioning, reversed-phase thin-layer chromatography (TLC), and argentation
TLC, the peak component was subjected to structural analyses. The partially hydrogenated products after reaction with hydrazine
hydrate gave seven isomers of cis-hexacosenoic acid (26:1). Gas chromatography-mass spectrometry (GC–MS) analyses of their dimethyl disulfide adducts identified
the monounsaturates as 5-, 8-, 11-, 14-, 17-, 20-, and 23-26:1. The peak component was assigned to all-cis-5,8,11,14,17,20,23-hexacosaheptaenoic acid (26:7n-3). GC–MS analyses of the 4,4-dimethyloxazoline derivative and methyl ester
confirmed this structure. This fatty acid is a rare, very long-chain polyunsaturated fatty acid (VLCPUFA). The concentrations
of the acid found in roughscale sole were 0.69 ± 0.34% (N = 5) of total fatty acids in flesh lipids. Roughscale sole appears to be characterized by the occurrence of 26:7n-3, which
is lacking in popular sources of methylene-interrupted VLCPUFA, such as vertebrate retina, spermatozoa, and herring. 相似文献
28.
Yuuki Kawabata Kimio Asami Masato Kobayashi Taku Sato Koichi Okuzawa Hideaki Yamada Kenzo Yoseda Nobuaki Arai 《Fisheries Science》2011,77(3):345-355
In this study, the effect of shelter acclimation on the post-release movement and putative predation mortality of hatchery-reared
black-spot tuskfish Choerodon schoenleinii was examined using acoustic telemetry. We acclimated four 1-year-old fish to shelters in cages before release and compared
their movements with six nonacclimated fish. Since it was not possible to compare the behavioral pattern between the former
and the latter fish due to the short periods the latter fish were available to be monitored, we also compared their movements
with those of large nonacclimated fish that were less likely to be preyed upon. Sixty-seven percent of the nonacclimated fish
showed atypical movements before the signals ceased to be detected, a pattern that suggested a predation event had occurred,
whereas none of the acclimated and large nonacclimated fish showed the atypical movements. In addition, the probability of
detection cessation was about 13 times lower in the acclimated than nonacclimated fish. The signal detection patterns suggest
that the acclimated fish utilized night-time shelters from the first night after release, while the large nonacclimated fish
started to utilize shelters several days after release. Therefore, it is likely that the shelter acclimation enhanced the
shelter utilization by tuskfish, possibly decreasing post-release predation mortality. 相似文献
29.
Hiromichi Mitamura Nobuaki Arai Yukiko Yamagishi Yuuki Kawabata Yasushi Mitsunaga Metha Khachaphichat Thavee Viputhanumas 《Fisheries Science》2009,75(1):175-182
The horizontal and vertical movements of eight immature hatchery-reared (F2) Mekong giant catfish Pangasianodon gigas were monitored using acoustic telemetry in the Mae Peum reservoir, Thailand, from September to December 2005. All tagged
fish were successfully monitored throughout the study period. All fish moved throughout the reservoir for approximately 1 month
after release. Subsequently, their utilized areas became small, and the fish utilized deep areas of the reservoir. The fish
displayed diel spatial movement patterns between deep areas in the day and shallow areas in the night. The vertical movements
of the fish were related to the environment declination such as existence of hypoxic water and thermocline. Our results suggest
that the establishment of a protected area in addition to conventional fisheries regulations may sustain the fish population
in this reservoir. 相似文献
30.
Hybrid breakdown (HB) is an important type of post-zygotic reproductive barrier that inhibits hybrid production during the process of cross-breeding. A novel low temperature-dependent HB was identified in a chromosomal segment substitution line (CSSL) library derived from a cross of two rice (Oryza sativa L. japonica) cultivars, Yukihikari and Kirara397. A set of weakness symptoms in a target CSSL was observed at 23°C, but was rescued at 27°C and/or 30°C. Genetic analysis of HB using an F2:3 population of a cross between a target CSSL and Kirara397 found that a recessive temperature sensitive hybrid breakdown1 (thb1) gene from Yukihikari caused HB in the genetic background of Kirara397. Molecular mapping showed that thb1 was located within a 199-kb fragment on chromosome 6. A genetic study of F2 populations of reciprocal crosses between Yukihikari and Kirara397 confirmed that this HB was induced by the interaction of two recessive genes. These results provide important clues to further dissect the mechanism of generation of a novel temperature sensitive HB in rice intrasubspecific crosses and suggest that these linked markers will useful in rice breeding. 相似文献