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Hisayuki Arakawa Yohei Ohi Akira Matsumoto Kenji Takio Takumi Kimoto Katsutoshi Kawabe 《Fisheries Science》2012,78(5):1083-1090
The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island. 相似文献
23.
Shintaro TOMURA Atsushi TOSHIMA Akira NOMURA Masahiko HIRATA Tetsushi YAMAGAMI Yumiko KAGAWA Tsuyoshi KADOSAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):439
An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses. 相似文献
24.
Sakamaki K Ishizaki S Ohkubo Y Tateno Y Fujita A 《Journal of agricultural and food chemistry》2011,59(12):6667-6671
A test apple beverage made up of apple juice (20%), high-fructose corn syrup (11.5%), citric acid (0.43%), trisodium citrate (0.02%), apple-odor flavor (0.1%), and ascorbic acid (0.02%) was stored at 40 °C and then analyzed for the change of odor in the beverage. Although no thermoacidophilic bacteria (TAB) were detected, a medicinal off-flavor was perceived after the 8 weeks of storage. Model experiments on the ingredients of the test apple beverage revealed that the off-flavor compound had been formed by ascorbic acid and (E)-hex-2-enal. Synthesis and NMR (1H, 13C, HMQC, and HMBC) analyses identified the compound as 6-propylbenzofuran-7-ol. The odor quality, retention index (RI), and mass spectrum of synthetic 6-propylbenzofuran-7-ol were identical with those of the medicinal odor compound from the test apple beverage. Sensory evaluation revealed the recognition thresholds for medicinal odor were 31.4 ppb in water and 24.0 ppb in apple beverage, and the detection thresholds were 19.6 ppb in water and 8.6 ppb in apple beverage, respectively. The quantified concentration of 6-propylbenzofuran-7-ol formed in test apple beverage was 90 ppb, approximately. This concentration was well above the odor threshold, so it was concluded that the compound was the source of the medicinal off-flavor. 相似文献
25.
Kinetic Parameters of Gross N Mineralization of Peat Soils as Related to the Composition of Soil Organic Matter 总被引:1,自引:0,他引:1
Bentio Heru Purwanto Akira Watanabe Jong Foh Shoon Ken-ichi Kakuda Ho Ando 《Soil Science and Plant Nutrition》2005,51(1):109-115
Peat land has been considered as an alternative type of land for agricultural development especially in the tropics. In the present study, the N-supplying capacity, one of the most important soil properties in terms of crop production, of peat soils was examined. Ten peat soil samples were collected from Indonesia, Malaysia, and Japan. Gross N mineralization in the soil samples was estimated using a zero-order model, and kinetic parameters of mineralization were determined using a simple type model. Soil organic matter composition was investigated using 13 C CPMAS NMR. Mineralization potential ( N 0 ), apparent activation energy ( E a ), and mineralization rate constant ( k ) ranged between 571–2,445 mg kg−1 , 281–8,181 J mol−1 , and 0.009–0.020 d−1 , respectively. Although none of the parameters showed a significant correlation with the soil C/N ratio, a negative correlation was observed between the k value and the ratio of the proportion of alkyl C in total C to that of O -alkyl C estimated by 13 C CPMAS NMR. The latter suggested that the k values were higher in the peat soils relatively rich in readily decomposable organic matter including carbohydrates. 相似文献
26.
Attaining inter-subgeneric hybrids in fragrant azalea breeding and the inheritance of organelle DNA 总被引:1,自引:0,他引:1
Inter-subgeneric hybrids were successfully obtained in reciprocal cross combinations between evergreen azaleas (Rhododendron nakaharae and its hybrids) and fragrant deciduous azaleas (R. arborescens and R. viscosum) for the purpose of fragrant evergreen azalea breeding. Nuclear and organelle DNA of these hybrids was investigated using
PCR-RFLP markers. Viable hybrid seedlings have nuclear ribosomal DNA (nrDNA) inherited biparentally, mitochondrial DNA (mtDNA)
from the seed parent, and chloroplast DNA (cpDNA) from the deciduous azalea, regardless of cross combination. These results
suggest that the chloroplast genome from deciduous azaleas and the nuclear genome from evergreen azaleas are compatible in
viable hybrid progenies. 相似文献
27.
Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil 总被引:2,自引:0,他引:2
To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, 13C CPMAS NMR spectra, and δ13C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and NaBH4+0.1 M Na4P2O7 (pH 10.5). It was found that the water- and 0.25 M Na2SO4-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH4+0.1 M Na4P2O7 (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields. 相似文献
28.
29.
Shinsuke MORI Akira KAWASAKI Satoru ISHIKAWA Tomohito ARAO 《Soil Science and Plant Nutrition》2009,55(2):294-299
Radioisotope techniques are well known as methods for evaluating symplastic ion absorption in roots. In the present study, a new method for evaluating symplastic cadmium (Cd) absorption in plant roots was developed using the enriched isotopes 113 Cd and 114 Cd. Seedlings of Solanum melongena were exposed to an enriched isotope solution of 113 Cd at 25°C for 30 min. The roots were excised from each seedling and were then immersed in a cold buffer solution without Cd at 2°C for 120 min to suppress the metabolic activity of the roots. Finally, the roots were treated with a cold buffer solution containing enriched stable isotope 114 Cd at 2°C for 120 min, whereby the apoplastically bound 113 Cd was desorbed. We tested the validity of our method for evaluating symplastic Cd in roots compared with the conventional method based on differences in the amount of Cd absorbed at 2°C and 25°C using unlabeled Cd. There was no difference in the symplastic Cd content of the roots between the two methods. These results indicate that it is possible to evaluate the symplastic Cd content in roots using the enriched isotopes 113 Cd and 114 Cd. 相似文献
30.
Nahoko Kurachi Tomiyasu Miyaura Jumpei Toriyama Yojiro Matsuura Akira Osawa 《Scandinavian Journal of Forest Research》2019,34(2):102-114
We estimated the aboveground net primary production (ANPP) in five self-thinning jack pine (Pinus banksiana) stands in Wood Buffalo National Park, NWT, Canada. The stands (11 to ca.175 years old) were selected to examine the relationship between stand density and tree size and its effect on carbon dynamics. Aboveground litterfall was collected from each stand from 1997 to 2012. Stand biomass was estimated by measuring tree size every 5 years and estimating the individual mass using allometric relationships. ANPP was then estimated by summing the litterfall mass, dead stem mass increment and stand biomass increment. We determined the proportional contribution of each organ to the total litter and the seasonal pattern of needle litterfall. There was a lower turnover rate of aboveground biomass in older stands than younger stands. The ANPP increased in the youngest stand (<30 years old) showed a decreasing trend in stands >50 years old. The maximum ANPP was estimated to be ca. 500?g m?2 year?1 in dry matter, which was found in 30–50 year-old stands. 相似文献