Phenolic extractives in the trunk of Toxicodendron vernicifluum: chemical characteristics,contents and radial distribution     

Koh Hashida  Masanobu Tabata  Katsushi Kuroda  Yuichiro Otsuka  Satoshi Kubo  Rei Makino  Yoshitaka Kubojima  Mario Tonosaki  Seiji Ohara 《Journal of Wood Science》2014,60(2):160-168

Phenolic extractives in the trunk of Toxicodendron vernicifluum (syn. Rhus verniciflua) were investigated. Seventeen compounds, gallic acid, protocatechuic acid, (?)-fisetinidol-4β-ol, (?)-fisetinidol-4α-ol, 2-benzyl-2,6,3′,4′-tetrahydroxycoumaran-3-one, (?)-fustin, 1,2,3,6-Tetra-O-galloyl-β-d-glucose, (?)-epifustin, (+)-taxifolin, 1,2,3,4,6-penta-O-galloyl-β-d-glucose, (?)-garbanzol, (?)-fustin-3-O-gallate, (?)-epifustin-3-O-gallate, fisetin, sulfuretin, quercetin and butein, were identified from the heartwood extractives. It was found that only (+)-taxifolin which had 5,7-dihydroxy A-ring possessed a 3R configuration although other flavonoids which had 7-hydroxy A-ring possessed a 3S configuration. Quantitative analysis revealed that the total phenolic contents were much higher in the heartwood (5–7 wt%) than in the sapwood and bark (1–2 wt%), and (?)-fustin was the most abundant extractive in the heartwood (1.4–2.4 wt%). For the radial distribution of phenolic extractives, it was generally found that their content was lowest in the sapwood, increased to the highest in the outer heartwood, and then decreased in the inner heartwood.  相似文献   

Comparisons of Internal Behavior after Exposure to Flavobacterium psychrophilum between Two Ayu (Plecoglossus altivelis altivelis) Strains Showing Different Cumulative Mortality to Bacterial Cold Water Disease     

Tetsushi KAGEYAMA  Tomonori KUWADA  Kenichi OHARA  Aya NOUNO  Tetsuya UMINO  Shuichi FURUSAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2013,75(12):1571-1575

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Evaluation of Premature Mortality Caused by Exposure to PM2.5 and Ozone in East Asia: 2000, 2005, 2020     

Amin Nawahda  Ken Yamashita  Toshimasa Ohara  Junichi Kurokawa  Kazuyo Yamaji 《Water, air, and soil pollution》2012,223(6):3445-3459

The aim of this study is to assess the premature mortality risks caused by exposure to particulate matter with aerodynamic diameter less than 2.5???m (PM_2.5) and ozone elevated concentrations for the years?2000, 2005, and 2020 in East Asia. The spatial distributions and temporal variations of PM_2.5 and ozone concentrations are simulated using the Models-3 Community Multiscale Air Quality Modeling System coupled with the Regional Emission Inventory in Asia. The premature mortality risks caused by exposure to PM_2.5 and ozone are calculated based on a relative risk (RR) value of 1.04 (95?% confidence interval (CI): 1.01?C1.08) for PM_2.5 concentrations above the annual mean limit of 10???g?m^?3 taken from the World Health Organization?CAir Quality Guideline and based on a RR value of 1.003 (95?% CI: 1.001?C1.004) for ozone concentration above 35?ppb of the SOMO35 index (the sum of ozone daily maximum 8-h mean concentrations above 35?ppb). We demonstrate one of the implications of the policy making in the area of environmental atmospheric management in East Asia by highlighting the annual premature mortalities associated with exposure to PM_2.5 concentrations that just meet an annual mean concentration of 10???g?m^?3, as well as ozone concentrations that have a daily zero SOMO35 index in vulnerable places. Our results point to a growing health risk that may endanger human life in East Asia. We find that the effect of PM_2.5 on human health is greater than the effect of ozone for the age group of 30?years and above. We estimate the corresponding premature mortality due to the effects of both ozone and PM_2.5 in East Asia for the years?2000 and 2005 to be around 316,000 and 520,000 cases, respectively. For future scenarios of the year?2020, policy succeed case, reference, and policy failed case, the estimated annual premature mortality rates are 451,000, 649,000, and 1,035,000 respectively.  相似文献   

Ectomycorrhizal‐fungal colonization induces physio‐morphological changes in Quercus serrata leaves and roots     

Naoki Makita  Yasuhiro Hirano  Takashi Yamanaka  Kenichi Yoshimura  Yoshiko Kosugi 《植物养料与土壤学杂志》2012,175(6):900-906

To determine how colonization by different ectomycorrhizal (ECM)‐fungal species affects the physiology and morphology of Quercus serrata seedlings, we assessed the net photosynthetic rate, the respiration rate of the lateral roots, leaf and root nitrogen (N) concentrations, specific leaf area, and specific root length in 9‐month‐old Q. serrata seedlings inoculated with Pisolithus tinctorius, Scleroderma citrinum, Laccaria amethystea, and Astraeus hygrometricus. While uninoculated control plants showed no colonization, the percentage of ECM colonization of root tips attained 35% with P. tinctorius and about 86% with the other three ECM species. Similar to ECM root colonization, the photosynthetic as well as the root‐respiration rates were higher in seedlings with S. citrinum, L. amethystea, and A. hygrometricus than that in the control and those with P. tinctorius. Both the photosynthetic and root‐respiration rates were positively correlated with ECM‐fungal colonization. Similar trends were observed for the N concentration, specific leaf area, and specific root length, which differed significantly among ECM‐fungal species and were related with ECM‐fungal colonization. The results suggest that both physiological and morphological traits are specific to ECM‐fungal species. As Q. serrata seedlings with high colonization can exhibit better resource‐acquisition ability, the identification of strongly colonizing ECM‐fungal species is essential. Comparisons with high‐ and low‐colonizing ECM‐fungal species improve our understanding of source–sink relationships in carbon allocation of forest tree species.  相似文献   

Chromospheric anemone jets as evidence of ubiquitous reconnection     

Shibata K  Nakamura T  Matsumoto T  Otsuji K  Okamoto TJ  Nishizuka N  Kawate T  Watanabe H  Nagata S  Ueno S  Kitai R  Nozawa S  Tsuneta S  Suematsu Y  Ichimoto K  Shimizu T  Katsukawa Y  Tarbell TD  Berger TE  Lites BW  Shine RA  Title AM 《Science (New York, N.Y.)》2007,318(5856):1591-1594

The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection.  相似文献   

Impaired Development of Somatotropes, Lactotropes and Thyrotropes in Growth-Retarded (grt) Mice     

Kobayashi K  Yamamoto K  Kikuyama S  Machida T  Kobayashi T 《Journal of toxicologic pathology》2009,22(3):187-194

Congenitally primary hypothyroid growth-retarded (grt) mice exhibit a characteristic growth pause followed by delayed onset of pubertal growth. We characterized the developmental pattern of somatotropes, lactotropes and thyrotropes in the anterior pituitary, as well as plasma levels of their secretory hormones, in grt mice. Compared with normal mice, the weight of grt pituitary gland was similar at 8 weeks of age but significantly heavier after 12 weeks of age. Compared with normal mice, there were significantly fewer somatotropes in the grt pituitary until 8 weeks of age, but the number gradually increased up to 48 weeks. The number of lactotropes in grt mice was consistently lower than that in normal mice from 2 through 48 weeks, whereas the number of thyrotropes in the grt pituitary was consistently higher than in the normal pituitary. Thyrotropes in the grt pituitary exhibited hypertrophy and hyperplasia with less intensive thyroid-stimulating hormone (TSH) immunoreactivity than normal thyrotropes. In normal mice, the sum of the relative proportions of these cells plateaued at 8 weeks, where it remained up to 48 weeks of age. In grt mice, these proportions almost reached normal levels at 12 weeks of age but gradually declined after 24 weeks. Plasma growth hormone concentrations did not differ between grt and normal mice until 24 weeks of age. Compared with normal mice, grt mice exhibited significantly lower plasma prolactin and thyroxine levels but higher TSH levels. These findings indicate that development of somatotropes, lactotropes and thyrotropes in grt mice is impaired, being followed by altered hormone secretion.  相似文献   

Survey of genetic variation at three microsatellite loci in captive populations of endangered Japanese minnow <Emphasis Type="Italic">Aphyocypris chinensis</Emphasis> with implications for reduction of inbreeding     

Kenichi Ohara  Motohiro Takagi 《Fisheries Science》2007,73(1):156-160

The Japanese population of the cyprinid minnow Aphyocypris chinensis is nearing extinction in the wild. The genetic diversity of three microsatellite loci in five captive populations was investigated, and an effective breeding strategy to reduce inbreeding from pairwise relatedness (R _xy ) between each captive line is discussed. The average number of alleles ranged 2.33–4.67 and the average heterozygosity ranged 0.283–0.602. The pairwise relatedness observed in most combinations showed a significant decrease between the populations. It is suggested that exchange of individuals between different breeding lines should effectively stop inbreeding. Studies show that the effective population size (N _e ) estimated from the number of parental individuals was 8.54 in one captive population, which is insufficient to maintain genetic diversity. It is recommended that more parental individuals should be used, and to exchange fish in a rotating mating mode between institutions participating in captive breeding of A. chinensis.  相似文献