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31.
Nitrogen removal from animal waste treatment water by anammox enrichment   总被引:8,自引:0,他引:8  
The aim of this work was to examine the applicability of the anaerobic ammonium oxidation (anammox) process to three kinds of low BOD/N ratio wastewaters from animal waste treatment processes in batch mode. A rapid decrease of NO(2)(-) and NH(4)(+) was observed during incubation with wastewaters from AS and UASB/trickling filter and their corresponding control artificial wastewaters. This nitrogen removal resulted from the anammox reaction, because the ratio of removed NO(2)(-) and NH(4)(+) was close to the theoretical ratio of the anammox reaction. Comparison of the inorganic nitrogen removal rate of the actual wastewater and that of control artificial wastewater showed that these two kinds of wastewater were very suitable for anammox treatment. Incubation with wastewater from RW did not show a clear anammox reaction; however, diluting it by half enabled the reaction, suggesting the presence of an inhibitory factor. This study showed that the three kinds of wastewater from animal waste treatment processes were suitable for anammox treatment.  相似文献   
32.
The sterol fractions of eight leafy liverworts were analyzed by GLC and GC-MS. Five 3β-sterols, cholest-5-en-3β-ol, 24-methylcholest-5,22-dien-3β-ol, 24-methylcholest-5-en-3p-ol, 24-ethylcholest-5,22-dien-3β-ol and 24-ethylcholest-5-en-3β-ol, were detected in all samples but there were differences in the relative amounts present.  相似文献   
33.
DNase B is a major nuclease and a possible virulence factor in Streptococcus pyogenes. The allelic diversity of streptococcal DNase B (sdaB) gene was investigated in 83 strains with 14 emm genotypes. Of the 15 alleles identified, 11 alleles carried only synonymous nucleotide substitutions. On the other hand, 4 alleles had a non-synonymous substitution other than synonymous substitutions, resulting in the substitution of a single amino acid. The distribution of each allele was generally emm genotype-specific. Only sdaB7 was found in both emm2 and emm4. The promoter region was highly conserved and DNase B protein was similarly expressed in all alleles.  相似文献   
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Elucidation of species interactions involving multiple processes is an important task in ecology, as different processes may operate in non‐apparent, opposing directions. While herbivory is a major form of interspecific interaction affecting plants, calcareous algae are generally thought to be protected from herbivory due to CaCO3 deposition. However, field observations and experiments in temperate‐subtropical intertidal rockpools showed that hermit crabs (Paguroidea, Decapoda) did not ingest Corallina but cut short its fronds. We tested the implications of this frond‐cutting behaviour with field experiments where hermit crab density and Corallina frond length were artificially manipulated. Hermit crab guts were fuller and contained more microscopic animals when Corallina fronds were shorter, suggesting that frond‐cutting affects accessibility to food resources that exist in the basal part of algal mat. Corallina showed compensatory growth when fronds were artificially reduced in length/density, simulating the cutting by hermit crabs. Frond density increased, probably due to increased exposure to light of the basal part of Corallina coupled with a reduction in apical dominance. The present study revealed a direct, non‐trophic relationship between hermit crabs and Corallina in which the former affected the latter for gaining access to food resources. Overall, the combination of positive and negative effects of hermit crab led to a positive, facilitative effect on Corallina. In terms of the effect on algae or plants, this relationship is functionally analogous to herbivory, without involving direct consumption. We discuss the problem of extending the concept of ecological engineering to herbivory and herbivory‐like phenomena and suggest the term ‘pseudo‐herbivory’ to describe relations in which animals have non‐trophic but herbivory‐like effects on plants/algae, as seen in the hermit crab–Corallina relationship.  相似文献   
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The multiplications of low level Legionella pneumophila serogroup 1 cells by the coculture procedure with Acanthamoeba castellanii were tested in five strains. The cells in all strains proliferated effectively for isolating. This procedure might be a useful means of improving the successful isolation from environmental and clinical specimens of low level Legionella cells, and pursuing the source of infection.  相似文献   
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Bacillus sp. strain TAT105 is a thermophilic, ammonium-tolerant bacterium that grows assimilating ammonium nitrogen and reduces ammonia emission during composting of swine feces. To develop a practical use of TAT105, a dried solid culture of TAT105 (5.3 × 109 CFU/g of dry matter) was prepared as an additive. It could be stored for one year without significant reduction of TAT105. Laboratory-scale composting of swine feces was conducted by mixing the additive. When the additive, mixed with an equal weight of water one day before use, was added to obtain a TAT105 concentration of above 107 CFU/g of dry matter in the initial material, the ammonia concentration emitted was lower and nitrogen loss was approximately 22% lower in the treatment with the additive than in the control treatment without the additive. The colony formation on an agar medium containing high ammonium could be used for enumeration of TAT105 in the composted materials.  相似文献   
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Adenosine-to-inosine RNA editing is crucial for generating molecular diversity, and serves to regulate protein function through recoding of genomic information. Here, we discover editing within Ca(v)1.3 Ca2? channels, renown for low-voltage Ca2?-influx and neuronal pacemaking. Significantly, editing occurs within the channel's IQ domain, a calmodulin-binding site mediating inhibitory Ca2?-feedback (CDI) on channels. The editing turns out to require RNA adenosine deaminase ADAR2, whose variable activity could underlie a spatially diverse pattern of Ca(v)1.3 editing seen across the brain. Edited Ca(v)1.3 protein is detected both in brain tissue and within the surface membrane of primary neurons. Functionally, edited Ca(v)1.3 channels exhibit strong reduction of CDI; in particular, neurons within the suprachiasmatic nucleus show diminished CDI, with higher frequencies of repetitive action-potential and calcium-spike activity, in wild-type versus ADAR2 knockout mice. Our study reveals a mechanism for fine-tuning Ca(v)1.3 channel properties in CNS, which likely impacts a broad spectrum of neurobiological functions.  相似文献   
40.
Abstract The 16S rRNA gene sequences of 19 strains covering 97% of the molecules were determined for the members of the family Rhizobiaceae and related bacteria by PCR and DNA sequencer. The three biovars of Agrobacterium were located separately, whereas Agrobacterium rubi clustered with A. tumefaciens . Phylogenetic locations for the species of the genera Rhizobium, Sinorhizobium, Agrobacterium, Phylobacterium, Mycoplana (M. dimorpha), Ochrobactrum, Brucella and Rochalimaea (a rickettsia) were intermingled with each other with the similarity values higher than 92%. The family Rhizobiaceae should be redefined including the above-mentioned genera despite the ability for plant association and nitrogen fixation. Bradyrhizobium japonicum and Mycoplana bullata were far remote from the other species and should be excluded from this family.  相似文献   
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