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51.
The interstices of coral rubble provide a good refuge for cryptic small crustaceans and molluscs, which are important prey items for reef fishes. In this study, we focused on the assemblage composition of cryptic mobile species along the depth gradient at an outer reef slope. Traps with coral rubble (22 × 18 × 6 cm) were set at three sites at different depths, and mobile animals that colonized the traps were sorted. In total, 117 species of larger animals (mainly Decapoda and Gastropoda) were recorded: 71 species at the 3 m point, 53 species at the 11 m point, and 37 species at the 22 m point. On average, 260.3 individuals were captured in the traps at 3 m, while 95.3 and 57.8 individuals were captured at 11 and 22 m, respectively. MDS ordination showed that assemblage composition differed among the three sites. The most abundant species at the 3 m was the galathean crab Galathea mauritiana, followed by the gastropod Diala albugo. At 11 and 22 m, the galathean crab Sadayoshia edwardsii was most abundant. Thus, at the reef slope, the benthic assemblage was most diverse at the shallow site, and specific communities occurred at the three sites.  相似文献   
52.
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   
53.
Morphological and immunohistochemical examinations were carried out on the pancreas of a hyperglycemic 5-year-old male cynomolgus monkey. Body weight gradually decreased from 6 months before termination, accompanying a slight reduction in food consumption and anorexia for the last 2 days. The blood glucose level was markedly elevated when examined at termination. Histopathologically, in the exocrine pancreas, diffuse hyperplasia of centroacinar and intercalated duct cells and diffuse atrophy of acinar cells with sporadic apoptosis were observed, although most centroacinar and intercalated duct cells were proliferating cell nuclear antigen (PCNA)-positive in both the present case and age-matched control animals. In the endocrine pancreas, the islets tended to be hypertrophic, with an increase in insulin-positive cells in comparison with the age-matched control animals. PCNA-positive cells also tended to increase in the islets, although positive cells for phospho-histone H3, a marker for mitotic cells, were not detected in the endocrine and exocrine pancreas. Moreover, neither inflammation nor amyloidosis was noted in the islets. In conclusion, the present case probably suffered from early-stage type 2 diabetes mellitus, and it provides fundamental information concerning pancreatic histopathology under insulin-related derangement in monkeys.  相似文献   
54.
Paddy and Water Environment - In the zone fill-type reservoir embankment, the vertical filter for drainage is essentially installed, but in the case of the horizontal filter, the applicability is...  相似文献   
55.
Alfalfa mosaic virus (AMV), Cucumber mosaic virus (CMV), Potato virus Y (PVY), Tomato bushy stunt virus nipplefruit strain (TBSV-Nf), and an unknown spherical virus were isolated from nipplefruit (Solanum mammosum) cultivated in Chiba Prefecture, Japan. The spherical virus was identified as Grapevine Algerian latent virus nipplefruit strain (GALV-Nf) from the genus Tombusvirus, based on its physical properties, serological relationships, and analysis of genomic RNA. The genomic RNA of GALV-Nf is 4731 nucleotides long and encodes five open reading frames as well as those of other tombusviruses. Nipplefruit infected with GALV-Nf had severe stunting, leaf deformation, and clear mosaic symptoms. This is the first report of an isolation of GALV in Japan. An erratum to this article is available at .  相似文献   
56.
OBJECTIVE: To determine the minimum anesthetic concentration for sevoflurane and effects of various multiples of minimum anesthetic concentration on arterial pressure and heart rate during controlled ventilation in chickens. STUDY DESIGN: Prospective experimental study. ANIMALS: Seven healthy chickens, 6 to 8 months old, weighing 1.6 to 3.4 kg. METHODS: A rebreathing, semiclosed anesthetic circuit was used. Anesthesia was induced by mask with sevoflurane in oxygen. Each chicken was endotracheally intubated, then controlled ventilation was started and the end-tidal CO2 partial pressure was maintained at 30 to 40 mm Hg. Body temperature was maintained at 39.5 degrees to 41.0 degrees C. The inspired and end-tidal sevoflurane concentration were monitored with a multigas monitor. Minimum anesthetic concentration was determined as the minimal end-tidal sevoflurane concentration which prevented gross purposeful movement in response to clamping a toe for 1 minute. After the determination, the cardiovascular effects of sevoflurane at 1.0, 1.5, and 2.0 times the minimum anesthetic concentration were determined. RESULTS: The minimum anesthetic concentration for sevoflurane was 2.21% + 0.32% (mean +/- SD). Mean arterial pressure and heart rate at minimum anesthetic concentration were 84 +/- 13 mm Hg and 150 +/- 58 beats/min, respectively. There was a dose-dependent decrease in arterial pressure. The heart rate did not change significantly over the range 1 to 2 x minimum anesthetic concentration. No cardiac arrhythmias developed throughout the experiments. CONCLUSIONS AND CLINICAL RELEVANCE: The minimum anesthetic concentration for sevoflurane in chickens was within the range of minimum alveolar concentration reported in mammals. When the concentration of sevoflurane is increased during controlled ventilation in chickens, decrease in arterial pressure should be expected.  相似文献   
57.
58.
A double quantum dot device is a tunable two-level system for electronic energy states. A dc electron current was used to directly measure the rates for elastic and inelastic transitions between the two levels. For inelastic transitions, energy is exchanged with bosonic degrees of freedom in the environment. The inelastic transition rates are well described by the Einstein coefficients, relating absorption with stimulated and spontaneous emission. The most effectively coupled bosons in the specific environment of the semiconductor device used here were acoustic phonons. The experiments demonstrate the importance of vacuum fluctuations in the environment for quantum dot devices and potential design constraints for their use for preparing long-lived quantum states.  相似文献   
59.
The metabolic fate of metofluthrin [2,3,5,6-tetrafluoro-4-(methoxymethyl)benzyl (E,Z)-(1R,3R)-2,2-dimethyl-3-(prop-1-enyl)cyclopropanecarboxylate] separately labeled with (14)C at the carbonyl carbon and the α-position of the 4-methoxymethylbenzyl ring was studied in cabbage ( Brassica oleracea ). An acetonitrile solution of (14)C-metofluthrin at 431 g ai ha(-1) was once applied topically to cabbage leaves at head-forming stage, and the plants were grown for up to 14 days. Each isomer of metofluthrin applied onto the leaf surface rapidly volatilized into the air and was scarcely translocated to the untreated portion. On the leaf surface, metofluthrin was primarily degraded through ozonolysis of the propenyl side chain to produce the secondary ozonide, which further decomposed to the corresponding aldehyde and carboxylic acid derivatives. In the leaf tissues, the 1R-trans-Z isomer was mainly metabolized to its dihydrodiol derivative probably via an epoxy intermediate followed by saccharide conjugation in parallel with the ester cleavage, whereas no specific metabolite was dominant for the 1R-trans-E isomer. Isomerization of metofluthrin at the cyclopropyl ring was negligible for both isomers. In this study, the chemical structure of each secondary ozonide derivative was fully elucidated by the various modes of liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) spectroscopy together with cochromatography with the synthetic standard, and their cis/trans configuration was examined by the nuclear Overhauser effect (NOE) difference NMR spectrum.  相似文献   
60.
The aerobic aquatic metabolism of flumioxazin was studied in two water-sediment systems under illumination and in darkness to investigate its degradation profiles. (14)C-Flumioxazin separately labeled at the 1- and 2-positions of the tetrahydrophthalimide moiety or uniformly labeled at the phenyl ring was applied to a overlying water at a rate equivalent to 600 g ai/ha by assuming uniform distribution in the water layer to a depth of 100 cm. Flumioxazin was rapidly degraded at 20 °C in the overlying waters irrespective of irradiation with half-lives of 0.1-0.4 day. Both various modes of liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) spectroscopy analyses showed four major degradates under irradiation. Two of them were formed via successive hydrolysis of the cyclic imide ring, and the others were 2-arizidinone derivatives via photoinduced rearrangement. The presence of sediment under illumination greatly reduced the formation of these degradates and accelerated their degradation. The partitions of flumioxazin and its degradates to the bottom sediment not only reduced their fractions in the water layer subjected to hydrolysis and photolysis but also enhanced their microbial degradation in the sediment. The illuminated water-sediment systems were considered to more adequately represent the behavior of flumioxazin and its degradates in the environment than the corresponding studies of aqueous photolysis and water-sediment in darkness.  相似文献   
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