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171.
172.
Tatsuhiko Nobuhiro Koji Tamai Yuji Kominami Takafumi Miyama Yoshiaki Goto Yoichi Kanazawa 《Journal of Forest Research》2003,8(4):297-301
A new system was developed for measuring soil CO2 efflux. The chamber in this system contains a small infrared CO2 gas analyzer. This system does not need air tubes or pumps for circulating air, so it is expected to offer the advantages of mobility and durability. This system was verified by a comparison with measurements made by using a closed-dynamic-chamber (CDC) system. The spatial variation in the soil CO2 efflux in a broadleaved deciduous forest was measured using the new system. The soil CO2 efflux at sampling locations 50–70cm apart varied within a range of 60%–150%. This variation was smaller than the variation due to differences in soil characteristic reflected in different moisture conditions, etc. 相似文献
173.
A series of two filtration experiments were conducted to evaluate the filtration function of forest soil experimentally. The
first experiment evaluated the differences between the filtration capabilities of the A0 horizon and A horizon, and the effect of overstory species on the filtration function of the A0 horizon. Undisturbed A0, A and A0+A horizons were collected for the filter mediums with cylindrical samplers. Leaves ofQuercus serrata, Quercus myrsinaeforia, Sasa senanensis Pinus densiflora, Chamaecyparis obtusa, andCryptomeria japonica were also packed in the samplers. Various suspended sediment concentration of water were sprayed at constant intensity on
the surface of samples. Filtering coefficients were not affected by SS concentration in all samples, and the order of filtering
coefficient was: A0 horizons>A0+A horizons>A horizons in undisturbed forest soil samples, andQuercus serrata>Sasa senanensis>Quercus myrsinaeforia>Pinus densiflora”Chamaecyparis obtusa>Cryptomeria, japonica in leaf samples. These results led to the conclusion that SS from managed forests can best be prevented by buffer zones where
a thick A0 horizon is maintained. The second experiment evaluated the effect of turbid water supply rate on the filtration capacity.
Undisturbed A horizons and four leaf types,Quercus serrata, Pinus densiflora, Chamaecyparis obtusa, andCryptomeria japonica were used as filter mediums. Filtering coefficients were inversely proportional to supply rate of turbid water in all samples. 相似文献
174.
The possibility of breeding white-grained wheats tolerant to pre-harvest sprouting under Japanese humid weather conditions
is discussed. New genetic dormancy sources, such as, AUS1408, 8019R1 and RyuuMai7, were evaluated for seed dormancy in different
weather conditions. Some white-grained dormant wheats showed a strong dormancy similar to that of red-grained dormant wheats
in a greenhouse trial, in the field their dormancy expression was much less than the red wheats. Three populations involving
crosses with these new sources for winter wheat breeding were examined under repeated selection for seed dormancy. Some dormant
white-grained lines, as judged under glasshouse conditions, were developed. Again the level of dormancy in these lines was
not sufficient compared to red dormant varieties in field trial. In order to develop truly superior dormant white-grained
materials, one population involving crosses with two dormant varieties, AUS1408 and 8019R1, was examined under repeated selection.
From these materials we succeeded in breeding lines that had not only a good dormancy but also showed adaptation to Japanese
weather conditions, including earliness, scab resistance and good seed appearance. However again the dormancy of these lines
in field trial was not sufficient compared to that of red wheats and there was not a clear difference for seed dormancy between
breeding lines and their parents. We conclude therefore that more work involving the use of new genetic sources or new breeding
techniques, will be necessary for breeding advanced lines that maintain a sufficient tolerance to PHS in humid Japanese weather
condition.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
175.
Tetsushi ONO Keiichi HISAEDA Yoichi INOUE Yutaka YAMADA Kenichi SHIBANO Ikki MITSUI Chizuka HENMI Yumi UNE Hideaki HAYASHI Sanggun ROH Masakatsu NOHARA Eiji UCHIDA Hajime NAGAHATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):220
This study reports findings from the pathological examination of the forestomach of an 11-month-old Japanese Black steer with severely retarded growth (41% of expected weight) and chronic ruminal tympany. The ruminal papillae were weakly formed (0.3–0.5 cm long) and unevenly distributed. The cellulae and cristae reticuli were underdeveloped; the cristae were 0.4–0.7 cm in height and milky white. The keratinized layer in the stratified squamous epithelium was thickened. Ruminal pH was 5.25, and ruminal volatile fatty acid concentration was 11.7 mM. The steer’s severely retarded growth was considered to be caused by malnutrition due to developmental and functional failure of the forestomach. 相似文献
176.
Oki T Masuda M Kobayashi M Nishiba Y Furuta S Suda I Sato T 《Journal of agricultural and food chemistry》2002,50(26):7524-7529
The extracts from white-, black-, and red-hulled rice were prepared by sequential extraction with six different polar solvents, and their radical-scavenging activities were measured by methods using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH*) and tert-butyl hydroperoxyl radical (t-BuOO*). The extracts prepared with highly polar solvents, methanol and deionized water, exhibited higher DPPH* and t-BuOO* scavenging activities in all three cultivars. In addition, the acetone extract from red-hulled rice exhibited a high DPPH* and t-BuOO* scavenging activity, while no such activity was detected for the acetone extracts from white- and black-hulled rice. The major components responsible for the radical scavenging in the acetone extract from red-hulled rice were identified as procyanidins by acidic hydrolysis, vanillin assay, and Sephadex LH-20 chromatography. GPC analysis of the acetylated procyanidins revealed that the average molecular weight is about 5000, in a range of about 500-18,000. 相似文献
177.
178.
A Shimada M Kuwamura T Awakura T Umemura C Itakura 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(1):29-36
The pattern of astrocytic gliosis (AG) was examined in 2-month-old to 18-year-old dogs using glial fibrillary acidic protein (GFAP) immunohistochemistry and electron microscopy. Coronal sections from various levels of the central nervous system (CNS) were stained with hematoxylin & eosin, Luxol Fast Blue, Nissl, and Bodian in addition to GFAP. A consistent pattern of age-related AG was observed in the dogs. The white matter, cortico-medullary junction, and subcortical nuclei in the cerebrum, central nuclei in the cerebellum, various nuclei in the brain stem, and grey matter of the spinal cord showed even and intense GFAP staining. AG was also prominent in the cerebral and cerebellar cortices and thalamus. Moderate AG was observed in the hippocampus and white matter of the cerebellum and spinal cord. Electron microscopy demonstrated increased number of profiles of degenerative neural components in the vicinity of hypertrophic astrocytes in the cerebral cortex of the aged dogs. Moderate to severe AG was consistently shown in the CNS of the aged dogs. In contrast, young normal dogs showed minimum amounts of GFAP-positive astrocytes in the CNS. These findings suggest that the observed AG in the CNS of the dogs is a morphological expression of aging. 相似文献
179.
180.