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排序方式: 共有267条查询结果,搜索用时 15 毫秒
71.
Abstract Recently, fungi with the ability of heterotrophic nitrification have been isolated from acid forest soils (Lang and Jagnow 1986; Stroo et al. 1986). It is suggested that under unsuitable conditions for autotrophic nitrification, heterotrophic processes for NO2 - and NO3 - production could be advantageous. 相似文献
72.
Hirokazu MATSUMOTO Hideaki MARUSE Kanako YOSHIZAWA Shinji SASAZAKI Akira FUJIWARA Takeki KIKUCHI Nobutsune ICHIHARA Fumio MUKAI Hideyuki MANNEN 《Animal Science Journal》2007,78(5):476-483
Muscular dystrophies, a group of inherited diseases with the progressive weakness and degeneration of skeletal muscle, contain genetically variable diseases. Though chicken muscular dystrophy with abnormal muscle (AM) has long been known, the gene responsible has not yet been identified. In this study, a resource family for AM was established with 487 F2 individuals and 22 gene markers, including microsatellite and insertion–deletion markers, were developed. The haplotypes were analyzed with these markers for the candidate region of GGA2q described in a previous study. The candidate region was successfully narrowed down to approximately 1Mbp. The region included seven functional genes predicted as the most likely AM candidates. 相似文献
73.
Dai Kusumoto Hayato Masuya Toshihide Hirao Hideaki Goto Keiko Hamaguchi Wen-I Chou Wiwat Suasa-ard Sawai Buranapanichpan Sopon Uraichuen Oraphan Kern-asa Sunisa Sanguansub Aumporn Panmongkol Thu Pham Quang Sih Kahono Heddy Julistiono Naoto Kamata 《Journal of Forest Research》2014,19(4):404-410
Japanese oak wilt (JOW) has been prevalent in Japan since the late 1980s. Infections of the fungus, Raffaelea quercivora Kubono et Shin. Ito, which is transmitted by an ambrosia beetle [Platypus quercivorus (Murayama)], can cause JOW. Although R. quercivora, P. quercivorus, and oak trees are distributed in other Asia–Pacific countries, the incidence of JOW has not been reported outside Japan. In this study, we collected R. quercivora isolates from 5 Asian countries, including Japan, and compared their ability to induce sapwood discoloration by inoculating Q. serrata logs. The tangential widths of the discoloration in sapwoods inoculated with non-Japanese isolates were equivalent to or greater than those of the 2 Japanese isolates. This indicates that a lack of JOW incidence outside Japan is not because of the lowered ability of R. quercivora to spread discoloration compared with the Japanese isolates. Statistical analyses of the relationship between discoloration and phylogeny based on DNA sequences of actin and chitin synthase showed that the discoloration width was independent of phylogenetic relatedness among the isolates. To discuss why the occurrence of JOW has not been reported outside Japan, further studies (e.g., on host susceptibility and P. quercivorus aggression) throughout Asia are needed. 相似文献
74.
Phenol–formaldehyde resin-bonded particleboard (PF board) and isocyanate resin-bonded particleboard (MDI board) were soaked in water at 40, 70 and 100 °C, and the relationships between soaking conditions and board properties were analyzed. The relationships between the deterioration of board properties resulting from water soaking and those arising from outdoor exposure were also analyzed. At 100 °C, the modulus of rupture (MOR) and internal bond strength (IB) of the PF board decreased significantly within the first hour, and subsequently constant values were shown with increasing soaking time. This low constant value was defined as the lower limit. At 70 °C, both the MOR and IB decreased with increasing soaking time, and reached the lower limit. At 40 °C, however, neither decreased significantly with increasing soaking time and neither reached the lower limit. The MOR of the MDI board showed the same trend as the PF board. However, the IB of the MDI board showed a different trend to the PF board, that is, the lower limit of IB required extensive soaking, even at 100 °C. The MOR and IB of both the PF and MDI boards reached the lower limit when thickness change peaked. On the other hand, the MOR and IB for outdoor exposure were lower than those for water soaking, even at the same thickness change. The MOR and IB of water soaking decreased owing to the collapse of the bonding points caused by board swelling. On the other hand, the board properties of outdoor exposure decreased owing to the collapse of the bonding points, and biodegradation also added to the decrease. 相似文献
75.
Miyamoto H Yano H Scheeres DJ Abe S Barnouin-Jha O Cheng AF Demura H Gaskell RW Hirata N Ishiguro M Michikami T Nakamura AM Nakamura R Saito J Sasaki S 《Science (New York, N.Y.)》2007,316(5827):1011-1014
High-resolution images of the surface of asteroid Itokawa from the Hayabusa mission reveal it to be covered with unconsolidated millimeter-sized and larger gravels. Locations and morphologic characteristics of this gravel indicate that Itokawa has experienced considerable vibrations, which have triggered global-scale granular processes in its dry, vacuum, microgravity environment. These processes likely include granular convection, landslide-like granular migrations, and particle sorting, resulting in the segregation of the fine gravels into areas of potential lows. Granular processes become major resurfacing processes because of Itokawa's small size, implying that they can occur on other small asteroids should those have regolith. 相似文献
76.
Hideaki Hayashi Chigusa Arai Yurie Ikeuchi Maho Yamanaka Takuji Hirayama 《Animal Science Journal》2021,92(1):e13518
The effect of growth and parturition on hair cortisol concentrations of cattle was investigated. Plasma, saliva, and hair (black and white from the shoulders and hip) samples were collected from calves at 6 and 24 weeks old and from dairy cattle at the dry (1 and 2 months prepartum) and lactation (10, 50, 150, and 250 days postpartum) periods. Plasma and saliva cortisol concentrations were lower in 24-week-old calves than those of 6-week-old calves, and hair cortisol concentrations decreased regardless of color and position. In 6-week-old calves, hair cortisol concentrations differed between sampling positions, but this difference was not observed in 24-week-old calves. Plasma and saliva cortisol concentrations increased before parturition until 10 days postpartum then decreased until 50 days postpartum. The same trend was observed in the cortisol concentrations of white hair. Contrarily, cortisol concentrations in black hair remained unchanged and was lower than that in white hair. Hair cortisol concentration can vary greatly depending on the location on the body, hair color, cattle age, or parturition. When this method is used, all of the above factors must be considered. 相似文献
77.
Using an aluminum (Al)‐sensitive maize cultivar, we investigated the influence of Al on the apoplastic solute bypass flow and its relationship with Al‐induced (1 h, 50 μM) callose formation and root growth. We selected the fluorescent probes 8‐hydroxypyrene‐1,3,6‐trisulfonic acid, trisodium salt (MW 524) (HPTS) and dextran‐Texas Red (TR) conjugates (MW 3,000, 10,000, and 40,000) to monitor their apoplastic transport. Confocal laser–scanning microscopy (CLSM) analysis and spectrofluorometric quantification showed Al‐induced callose formation in peripheral root cells within 1 h. Pretreatment of plants with the callose synthesis inhibitor 2‐deoxy‐D‐glucose (DDG) reduced the callose formation by half. Uptake experiments with both HPTS and dextrans showed uniform dye distribution in control root apices. After Al treatment for 1 or 2 h, which inhibited root growth by 32% or 50%, respectively, the dyes accumulated in the epidermal and outer cortical cell layers, especially in the 1–2 mm apical root zone. Al treatment reduced the export of the dyes out of the apical 1 cm treatment zone. This was due to strong sorption of HPTS but not of dextrans by Al‐loaded cell walls. Aluminum treatment reduced loading into the xylem sap particularly of higher–molecular weight dextrans. Pretreatment of roots with DDG and presence of 50 mM mannitol during the Al treatment partially forestalled the inhibitory effect of Al on the dye transport, but only slightly reduced the Al‐induced growth inhibition. Exudation experiments revealed that xylem water flow remained unaffected by the Al treatment of the root tips. The results with dextran suggest that Al binding in cell walls of the root apex inhibits apoplastic bypass flow of higher–molecular weight solutes, which might contribute to Al‐induced inhibition of root growth. 相似文献
78.
79.
Young Pacific bluefin tuna Thunnus orientalis with archival tags were released in the East China Sea. Time-series data for depth, and ambient and peritoneal temperatures
for nine fish, recorded every 128 s, were analyzed. Our objectives were to describe monthly changes in diving patterns in
relation to the ambient thermal structure and the occurrence of feeding events during March–June, and to discuss possible
reasons why bluefin tuna repeatedly dived to depths below the thermocline in terms of their thermoconservation mechanisms.
It was found that the fish repeatedly dived through the thermocline at intervals of 1.2 h on average, and the dive frequency
was high during March–May. However, the dive frequency and periodicity decreased in June, when the gradient became steeper.
In contrast, feeding events increased in June. These results indicate that from March to May, bluefin tuna repeatedly dive
because food biomass is inadequate at the surface, and they stop undertaking repeated dives in June when food becomes more
readily available at the surface, in addition to low visibility caused by low solar radiation. Further, the range of heat
transfer times for these fish was so long that their peritoneal temperature was probably maintained by engaging in brief dives.
The periodicity of dives may lead to a lower fluctuation in the peritoneal temperature, suggesting that the dives are a kind
of behavioral thermoregulation. 相似文献
80.
Rini?Pujiarti Yoshito?OhtaniEmail author Hideaki?Ichiura 《Journal of Wood Science》2011,57(5):446-451
Melaleuca leucadendron Linn. leaf oils from Gunung Kidul, Gundih and Sukun, Java, Indonesia, at tree ages of 5, 10, and 15 years were analyzed to
elucidate their qualities and chemical compositions. These oils gave yields from 0.61% to 1.59%. The samples from Gundih produced
the highest yields (1.42–1.59%) compared to those from Gunung Kidul and Sukun. These oils were colorless with an odor typical
of Melaleuca oils. The specific gravity of essential oils in this study ranged from 0.870 to 0.912. The samples from Gunung Kidul were
the highest in specific gravity (0.905–0.912). The refractive index values of oil samples ranged from 1.468 to 1.470, optical
rotation ranged from (−)2.47° to (−)0.98°, and ratio miscibility of oils in 70% ethanol ranged from 1:1 to 1:9.67. The organoleptic
profiles and physicochemical properties of M. leucadendron Linn. leaf oils in this study were evaluated based on the Indonesian National Standard (SNI) 06-3954-2006 for standard quality
of Melaleuca essential oils; only a few specific gravity values were below the standard. GC-MS spectrometry analysis indicated the presence
of 26 compounds. Among them, 1,8-cineole (44.76–60.19%), α-terpineol (5.93–12.45%), d(+)-limonene (4.45–8.85%), and β-caryophyllene (3.78–7.64%) were the major components. Samples from each site tended to decrease in 1,8-cineole content and
increase in β-caryophyllene content as plant age increased. α-Terpineol was highest at plant age 10 years, and d(+)-limonene varied according to plant site and age. 相似文献