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51.
In order to clarify the long-range transport of atmospheric pollutants in the East Asian regions, we have studied the components in rime ice on Yakushima Island, located in southwestern Japan near the China continent. The presence of a large number of particles has been found in the rime ice. Very small particles whose diameters are around 1 µm were identified as coal fly ash. The air mass at an altitude between 1500 m to 2000 m was probably long-range transported in association with a stable atmospheric layer in which the particles were efficiently scavenged by supercooled droplets. A back trajectory analysis also indicated the predominance of a north wind in the winter and in the other seasons as well. Such transport and deposition mechanisms may produce the greater pollutant deposition sometimes observed in mountain areas. Similar events may not be rare and could make an important contribution to the annual pollutants. 相似文献
52.
53.
Haraguchi K Kato Y Ohta C Koga N Endo T 《Journal of agricultural and food chemistry》2011,59(24):13102-13109
Marine sponges collected in Palau, Micronesia, were investigated for hydroxylated or methoxylated analogues of brominated diphenyl ethers (BDEs), brominated dibenzo-p-dioxin (BDD), and brominated biphenyls. The neutral fractions of Haliclona sp. and Callyspongia sp. contained 2'-methoxy-2,3',4,5'-tetraBDE, 6-methoxy-2,2',4,4'-tetraBDE, 2',6-dimethoxy-2,3',4,5-tetraBDE 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl, several methoxy-triBDEs, and dimethoxy-penta-/hexaBDEs. The methoxylated BDEs in sponges were strikingly similar to those of local fish living in the western Pacific Ocean. The total concentrations of these compounds (ΣMeO-PBDE) in both sponges were 63.5 μg/g extractable organic matter (EOM) for Haliclona sp. and 36.5 μg/g EOM for Callyspongia sp., which were about 2 orders of magnitude higher than the levels seen in tropical coral reef fish (unicornfish or surgeonfish) (280-290 ng/g lipid) and groupers (550 ng/g lipid) from Okinawan coastal waters. The phenolic fractions of both sponges contained hydroxy-methoxy tetra-/pentaBDEs as well as hydroxy-tetraBDD, in addition to the corresponding phenolic tetraBDE analogues. Although the total concentrations of phenolic products (27-80 μg/g EOM) in both sponges fell within a range comparable to the methoxylated products, ΣOH-PBDE in local fish were trace level (less than 10 ng/g lipid of) or undetectable. This survey indicates that marine sponges are a possible source of the MeO-PBDE analogues that biomagnify via the food chain to the higher trophic organisms in the western Pacific, whereas the distribution of the corresponding hydroxylated analogues is limited. 相似文献
54.
Ono Kenji Noguchi Hironori Noguchi Kyotaro Imaya Akihiro Ugawa Yuichi Komoriya Akane Tachibana Ryuichi Murakami Hisanori Kida Kimihiro Kawahihashi Masayuki 《Journal of Soils and Sediments》2021,21(5):2035-2048
Journal of Soils and Sediments - To restore the disaster resilience of coastal forests in tsunami-prone areas, growing bases have been artificially constructed with embanking before afforestation... 相似文献
55.
To evaluate the role of NH4 + assimilates in dark carbon fixation in roots in providing carbon skeletons expended for NH4 + assimilation, the rate of dark carbon fixation in roots was measured using NaH14CO3. The 14C-metabolites were analyzed in wheat (Triticum aestivum L.) plants grown in NH4 + media for various periods of time with or without methionine sulfoximine (MSX) treatment. The dark carbon fixation rate in the roots of wheat plants that had been grown with NH4 + for 1 d was approximately 6-fold higher than the rate in control roots. The stimulation of dark carbon fixation in NH4 +-grown plants, however, was not observed in MSX-treated roots. In the roots of NH4 +-grown plants, the concentration and 14C-Iabeling of acidic metabolites such as citrate and malate considerably decreased whereas those of basic metabolites, especially asparagine, increased noticeably. With MSX treatment, the incorporation of 14C into basic metabolites was negligible. In response to NH4 +, phosphoenolpyruvate carboxylase (PEPC) activity increased, and PEPC proteins accumulated in wheat roots. Neither activity nor amounts of PEPC in roots increased in the presence of MSX. These findings suggest that primary assimilation of NH4 + in roots is essential for the stimulation of dark carbon fixation, which coincides with the increased activity of root PEPC, to sufficiently replenish carbon skeletons necessary for NH4 + assimilation. 相似文献
56.
Nobuhisa Koga 《Soil Science and Plant Nutrition》2013,59(4):396-404
ABSTRACTTo identify efficient field management practices for enhanced soil carbon sequestration suited to crop rotation-based Andosol fields in northern Japan, the impacts of a combination of tillage, fertilizer type, and plant residue input on soil carbon sequestration rates were studied in a 4-year field experiment (April 2007 to March 2011). The rates of changes in soil organic carbon over the entire study period were determined by soil carbon stock change and by net ecosystem carbon budget. Across eight field management treatments and two replicates for each treatment, the rates of changes in soil organic carbon determined by net ecosystem carbon budget were positively correlated with the rates determined by soil carbon stock change (r = 0.766, n = 16). The arithmetic means of the rates determined by net ecosystem carbon budget (1.24 Mg C ha?1 year?1) were greater than those determined by soil carbon stock change (?0.18 Mg C ha?1 year?1) because decomposing crop residues and composted cattle manure in soil were included in the calculation of the net ecosystem carbon budget but were excluded in the calculation of soil carbon stock change (decomposing crop residues and composted cattle manure in soil samples were removed by sieving in measuring the soil carbon stock change). Both methods led to the same conclusion that soil carbon sequestration was significantly enhanced by composted cattle manure application and increased input of plant carbon from crop residues and green manure but was not enhanced by reduced tillage. The p values for net ecosystem carbon budget were smaller than those for soil carbon stock change in analysis of variance; therefore, the net ecosystem carbon budget was more sensitive to field management practice than the soil carbon stock change. 相似文献
57.
58.
Hidetoshi Ishibashi Hideyuki H. Motohashi Mami Kumon Kazuhiro Yamamoto Hironori Okada Takashi Okada Kazuhiko Seki 《Animal Science Journal》2013,84(11):740-743
The use of the common marmoset monkey in biomedical research has increased recently, and further attention has been devoted to this model after the successful production of transgenic marmosets. To extend genetic engineering approaches to widespread biomedical research fields, efficient prolonged in vitro culturing of embryo development is necessary. We aimed to evaluate the effects of the size of the zona pellucida opening on promoting the hatching process in the marmoset embryo. Piezo‐microdrilling of a 6‐μm opening in eight embryos resulted in four partially hatched embryos and one hatched embryo after 5 days of culture. Piezo‐microdrilling a 20‐μm opening in 11 embryos resulted in nine partial hatchings and no hatched embryos. Piezo‐scraping an 80‐μm opening in six embryos resulted in no partially hatched embryos and five hatched embryos. These results suggest that an 80‐μm opening, rather than 6‐μm or 20‐μm openings, is suitable to complete the hatching process in the marmoset embryo. 相似文献
59.
Jun YAMASHITA Hironori OKI Telhisa HASEGAWA Takeshi HONDA Tetsuro NOMURA 《Journal of Equine Science》2010,21(3):39-45
Genetic contributions of nine historically important ancestors and allelic diversity in
the Japanese Thoroughbred population were examined by applying the gene dropping
simulation to the foals produced from 1978 to 2005. Full pedigree records traced to
ancestors (base animals) born around 1890 were used for the simulation. Alleles originated
from some of the historically important ancestors were found to be at risk of future
extinction, although their genetic contributions to the foal population have increased
during the last three decades. The proportion of surviving alleles to the total alleles
assigned to the base animals was 8.0% in the foal population in 2005, suggesting that a
large part of genetic variability contained in the base animals is extinct in the current
population. 相似文献
60.
Yoshio Kijidani Noriko Sakai Keita Kimura Yoshitake Fujisawa Yuichiro Hiraoka Junji Matsumura Shinya Koga 《Journal of Wood Science》2012,58(6):471-478
Hinoki (Chamaecyparis obtusa) wood has been used as a structural material in Japan because of its superior mechanical properties, its excellent durability and the beautiful color of its heartwood. Variations of termite resistance and compositions of extractives among hinoki trees have been reported. However, genetic variation of termite resistance and the effect of heartwood color on termite resistance remain unknown. In this study, we report the characteristics of termite resistance and color indexes (L*, a* and b*) of heartwood of hinoki half-sib families in a progeny test stand. The survival days of termites and the mass loss of samples of hinoki heartwood differed significantly among hinoki families. Families with red-color heartwood had larger termite resistance than families with yellow-color heartwood. The termite resistances of individual samples from two families with yellow-color heartwood were as small as that of Pinus densiflora. Larger a* and smaller b* induced larger termite resistance of heartwood. The effect of DBH (diameter at breast height) of hinoki trees on termite resistance of hinoki families was small. 相似文献