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71.
72.
The efficacy of advanced treatment of swine wastewater using thermally polymerized, modified amorphous silica and hydrated lime (M‐CSH‐lime) for color and phosphorus removal and sulfur for nitrogen removal was examined with a demonstration‐scale treatment plant. The color removal rate was approximately 78% at M‐CSH‐lime addition rates of > 0.055 wt/v%. The ‐P removal rate exceeded 99.9% with > 0.023 wt/v%. pH of the effluent from the M‐CSH‐lime reactor increased with the addition rate till a maximum value of 12.7, which was effective in disinfection. The recovered M‐CSH‐lime would be suitable as a phosphorus fertilizer because the total P2O5 content was approximately 10%. The nitrogen oxide (NOx‐N) removal rate by sulfur denitrification increased to approximately 80% when the NOx‐N loading rate was around 0.1 kg‐N/ton‐S/day. It was suggested that the combination of the two processes would be effective in the advanced treatment of swine wastewater.  相似文献   
73.
Cross-incompatibility caused by endosperm abortion was found in advanced generations of backcrossing between the Asian wild (W593) and cultivated (T65wx) rice strains. The near isogenic line, T65WxS 6 (W593), carrying a segment of chromosome 6 from W593 showed a low seed setting when pollinated with pollen grains of T65wx in spite of the fact that the reciprocal cross gave a high seed setting. The unidirectional or asymmetric crossing barrier was previously explained by an interaction between Cif and cim, both of which acted sporophytically, resulting in the cross-incompatibility reactions in the female (CIF) and male (CIM), respectively. In the genetic model, endosperm abortion is induced only when CIF gametes are fertilized with CIM gametes. This predicted that the double homozygote for Cif and cim might be self-incompatible since the plant expresses both CIF and CIM simultaneously. However, we failed to obtain such a self-incompatible plant by transferring Cif into a cim plant. The present results showed that CIF is controlled not only by Cif but also by an additional gene(s) loosely linked with it. We propose here that Cif 1 (formerly named as Cif) and Cif 2 determine CIF. In addition, Cif 2 and Cim were not separated due to restriction of recombination, which might explain why it is difficult to obtain a self-incompatible rice plant expressing both CIF and CIM.  相似文献   
74.
Fish assemblage structures in fragmented and continuous seagrass habitats in Trang Province, Thailand, were examined in detail to elucidate the effects of habitat fragmentation. The assemblage structures clearly differed: fish species diversity was apparently higher in the fragmented seagrass beds, although total fish numbers did not differ between them. A total of 37 fish species were collected, including 24 and 34 species from the continuous and fragmented beds, respectively. Thirteen species were restricted to the fragmented beds, compared with three restricted to the continuous beds. In addition, eight species were more abundant in the fragmented beds and only two in the continuous beds. Such differences may have arisen, at least in part, from differences in microhabitat diversity and the relative amounts of microhabitats between the two habitat types, as well as specific microhabitat preferences of the resident fishes. Although fragmented beds supported greater fish species diversity at the present study sites, it is axiomatic that habitat fragmentation caused by anthropogenic disturbance is unacceptable, with seagrass-habitat conservation being essential for both the preservation of high overall biodiversity and the successful management of local fisheries.  相似文献   
75.
A passive acoustic telemetry survey was conducted to determine occurrence patterns of commercially important fishes on a steep reef slope along a marine protected area (MPA) in the southern Philippines, where the outer reef edge is often set as an offshore MPA boundary. Based on 4–61 days of tracking data from 21 detected individuals of five species (Lutjanus argentimaculatus, Lutjanus monostigma, Lethrinus atkinsoni, Lethrinus obsoletus, and Siganus guttatus; 20.7–69.2 cm fork length) caught near the reef slope of the MPA, S. guttatus occurred most frequently on the reef flat of the MPA, whereas all individuals of the four lutjanid and lethrinid species were primarily (99.4–100%) detected near the reef slope, and nine individuals (56.3% of these four species) of three of these species (not L. obsoletus) most likely used the shallow (≤10 m) and deep (≥20 m) layers, and thus, middle layers of the slope. These findings indicate that commercially important lutjanid and lethrinid species predominantly and vertically used the areas near the reef slope, suggesting the importance of fully including reef slopes in MPAs to enhance their effectiveness for the conservation of such fishes.  相似文献   
76.
In order to clarify the mechanisms determining fish distribution patterns in a mangrove system on Iriomote Island, in southern Japan, fish assemblage structures were determined by visual observation, along with food abundance and environmental factors, in an area of mangrove roots on the banks, and a bare sand area at the center, within downstream, midstream and upstream portions of a branch creek from the Urauchi River. The fish assemblage structures differed significantly between the area types, with the mangrove-root area supporting a more diverse and abundant fish fauna. A canonical correspondence analysis revealed that the relationships between fish distribution and their food abundance differed among trophic groups. Benthic crustacean or plant feeders were positively associated with their prey i.e. crabs and macroalgae—in other words, these trophic groups were abundant in downstream and/or midstream mangrove-root areas in which their prey were also particularly abundant. However, zooplankton feeders did not show such relationships, their abundance being positively associated with fine sediment particles (characteristic of areas with weak water movement). These results suggested that food availability is a major factor determining the distribution patterns of benthic crustacean feeders and plant feeders, whereas for zooplankton feeders other factors, such as sheltering effects against water current and/or predators, may be more significant.  相似文献   
77.
The whiteness of cooked rice and rice cakes was evaluated using a portable spectrophotometer with a whiteness index (WI). Also, by using boiled rice for measurement of Mido values by Mido Meter, it was possible to infer the whiteness of cooked rice without rice cooking. In the analysis of varietal differences of cooked rice, ‘Tsuyahime’, ‘Koshihikari’ and ‘Koshinokaori’ showed high whiteness, while ‘Satonoyuki’ had inferior whiteness. The whiteness of rice cakes made from ‘Koyukimochi’ and ‘Dewanomochi’ was higher than the whiteness of those made from ‘Himenomochi’ and ‘Koganemochi’. While there was a significant correlation (r = 0.84) between WI values and whiteness scores of cooked rice by the sensory test, no correlation was detected between the whiteness scores and Mido values, indicating that the values obtained by a spectrophotometer differ from those obtained by a Mido Meter. Thus, a spectrophotometer may be a novel device for measurement of rice eating quality.  相似文献   
78.
ABSTRACT

Chitin, which is the polymer of N-acetylglucosamine (GlcNAc) linked by β1,4 glycoside bonds, has been reported as a soil amendment to mitigate plant soil diseases, increasing the population of chitin-degrading bacteria, and chitinolytic enzymatic activity in the soil. In some chitin-degrading bacteria, whose chitinolytic systems have been intensively studied, the chitin degradation product N,N?-diacetylchitobiose {(GlcNAc)2} induces expression of genes for chitinases whereas GlcNAc does not. To evaluate the effects of these mono- and disaccharides on the population and activity of chitinolytic bacteria in soil, we investigated the chitinolytic enzyme activity and bacterial community structure in an incubated upland soil supplemented with GlcNAc or (GlcNAc)2. The added GlcNAc and (GlcNAc)2 (2 mg g?1) were consumed within 1 d when incubated at 25°C. Chitinase activity was induced by (GlcNAc)2 and chitin after 1-d and 7-d incubation, respectively, but not by GlcNAc. N-acetylglucosaminidase (GlcNAcase) activity was induced by GlcNAc but was lower than those by (GlcNAc)2 and chitin. Amplicon sequencing analysis targeting 16S rRNA genes demonstrated that both GlcNAc and (GlcNAc)2 significantly increased the rate of the order Bacillales, but the compositions of Bacillales differed from each other: the family Planococcaceae significantly increased in either GlcNAc- or (GlcNAc)2-added soil, but the genera Bacillus and Paenibacillus were increased mainly by GlcNAc and (GlcNAc)2, respectively. The family Streptomycetaceae of the order Actinomycetales was significantly increased by (GlcNAc)2 and chitin, but GlcNAc did not. Thus, GlcNAc and (GlcNAc)2, which were promptly consumed in the incubated soil, indicated partly similar but distinctive effects on chitinolytic enzyme activity and bacterial communities. Both aminosugars increased GlcNAcase activity and the population size of Planococcaceae. GlcNAc increased Bacillus. Chitinase activity and the populations of Paenibacillus and Streptomycetaceae, a number of strains of which are known as potent chitin-degraders, were increased by (GlcNAc)2, but not by GlcNAc.  相似文献   
79.
BACKGROUND: Trichoderma asperellum SKT-1 is a microbial pesticide of seedborne diseases of rice. To investigate the mechanisms of disease suppression in SKT-1, the ability to induce systemic resistance by SKT-1, or its cell-free culture filtrate (CF), was tested using Arabidopsis thaliana Col-0 plants. RESULTS: Both SKT-1 and its CF elicit an induced systemic resistance against the bacterial leaf speck pathogen Pseudomonas syringae pv. tomato DC3000 in Col-0 plants. Involvement of plant hormones in the induced resistance by SKT-1 and CF was assessed using Arabidopsis genotypes such as the jasmonic acid (JA)-resistant mutant jar1, the ethylene (ET)-resistant mutant etr1, the plant impaired in salicylic acid (SA) signalling transgenic NahG and the mutant npr1 impaired in NPR1 activity. In soil experiments using SKT-1, no significant disease suppression effect was observed in NahG transgenic plants or npr1 mutant plants. Expression levels of SA-inducible genes such as PR-1, PR-2 and PR-5 increased substantially in the leaves of Col-0 plants. Expression levels of JA/ET-induced genes such as PDF1.2a, PR-3, PR-4 and AtVsp1 were also induced, but the levels were not as high as for SA-inducible genes. In a hydroponic experiment using CF from SKT-1, all Arabidopsis genotypes showed an induced systemic resistance by CF and increased expression levels of JA/ET- and SA-inducible genes in leaves of CF-treated plants. CONCLUSION: The SA signalling pathway is important in inducing systemic resistance to colonisation by SKT-1, and both SA and JA/ET signalling pathways combine in the signalling of induced resistance by CF. These results indicate that the response of A. thaliana is different from that found in root treatments with barley grain inoculum and CF from SKT-1. Copyright © 2011 Society of Chemical Industry  相似文献   
80.
Porencephaly was observed in a female cynomolgus monkey (Macaca fascicularis) aged 5 years and 7 months. The cerebral hemisphere exhibited diffuse brownish excavation with partial defects of the full thickness of the hemispheric wall, and it constituted open channels between the lateral ventricular system and arachnoid space. In addition, the bilateral occipital lobe was slightly atrophied. Histopathologically, fibrous gliosis was spread out around the excavation area and its periphery. In the roof tissue over the cavity, small round cells were arranged in the laminae. They seemed to be neural or glial precursor cells because they were positive for Musashi 1 and negative for NeuN and GFAP. In the area of fibrous gliosis, hemosiderin or lipofuscin were deposited in the macrophages, and activated astroglias were observed extensively around the excavation area.  相似文献   
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