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1.
Based on pollen and floral morphology,Blechum grandiflorum is transferred toRuellia, and the nameR. mirandana is proposed for this species. A new species,Ruellia tuxtlensis, is described which is distinguishable fromR. mirandana by its longer spike and elliptic bracts. It is presently known only from the lowlands of Veracruz, Mexico.  相似文献   
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In the fertile rice line IR 36 there are two copies of the apocytochrome b (cob) gene: a functional copy, cob 1, and a pseudogene, cob 2 (Kaleikau et al. 1992). In a survey of diverse rice lines, we found that cob 2 was absent in the wild abortive(WA)-type cytoplasmic male-sterile cytoplasm, but was present in the fertile lines. While cob 1 was conserved among all the lines, fertile and sterile, the cob 2 region was different in the fertile lines tested. The 5′ regions of most cob 2 loci were similar to cob 1 (about 4 kb of the flanking region and most of the coding region), but the 3′ region varied among different fertile lines. The point of divergence, the break-point, from the cob 1 sequence was conserved in all the cob 2 regions tested. In all the cob 2 regions, this break-point seems to be linked to the variable region of cob 2 through a conserved 192-bp segment, which is not a part of cob 1. It is proposed that the cob 2 regions could have been produced by recombination or insertion events involving cob 1 and the 192-bp segment which is present at different locations in the mitochondrial genomes of the various rice lines.  相似文献   
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Ion-specific electrodes were used to study the binding of Hg2+, Pb2+, Cu2+, and Cd2+ ions to widely used bacterial growth media (Nutrient broth, trypticase soy broth, the medium of Foot and Taylor [6] and of Nelsonet al.[12]) and to media components [yeast extract, peptone, tryptone, proteose peptone, and casamino acids (acid hydrolyzed casein)]. Volatilization of Hg2+ from aqueous solutions could be prevented by any of the growth media or their components. All media bound large amounts of Hg2+, Pb2+, and Cu2+, but much less Cd2+. Of the media components, casamino acids showed the most binding activity for all metal ions; the relative affinity of other media components to different ions varied with the cation studied. In general, the Irving-Williams [8] series for cation affinity to organic ligands was followed: Hg2+>Pa2+ Cu2+ Cd2+.After adding 20 ppm of Hg2+, Pb2+, or Cu2+ (concentrations inhibitory to the growth of most microorganisms) to the growth media, 80 ppb or less remained as free cations in the solution. This might suggest that such ions enter bacterial cells as organic complexes, or that bacterial cells can compete successfully with growth media for the bound ions.  相似文献   
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Bioprocess and Biosystems Engineering - Despite the green energy generation with low cost compared to conventional fuel cells, microbial fuel cells (MFCs) still suffer with anode related...  相似文献   
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Plant and Soil - Upland rice production is often constrained by phosphorus deficiency (P) and drought events. Methods are needed to maximize P use efficiency, while promoting deep root development...  相似文献   
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This study investigates the effects of dietary Aeromonas veronii V03 supplementation on growth performances, innate immunity, and expression of immune-related genes in lymphoid organs of Cyprinus carpio and resistance to Aeromonas hydrophila infection. Fish were fed for 4 weeks with basal diet (BD; without probiotic), and experiment diet containing different doses of A. veronii V03 at 3.2 × 107 (DI) and 3.5 × 109 (DII) CFU g−1 of diet. At the end of the probiotic feeding trial, fish were challenged with A. hydrophila, and the percentage of survival rates was recorded over 7 days. Results revealed that fish fed with A. veronii V03 demonstrated a significant improvement in growth and enhancement of innate immunity, including respiratory burst, myeloperoxidase, and lysozyme activities, and total immunoglobulin level compared with BD fed to fish. Relatively, expression of cytokines (MyD88, IL-1β1, IL-8, and IL-10) and c- and g-type lysozymes were significantly up- and downregulated in lymphoid organs of fish. Moreover, dietary supplementation of A. veronii V03 exhibited significantly (p < 0.001) higher survival rates of DI (90%) and DII (96.66%) compared with BD (53.33%) fed fish against A. hydrophila infection. These findings help to understand the effects of probiotic A. veronii V03 administrated feed influences on growth and ailment resistance to A. hydrophila infection by regulating innate and systemic immunity in common carp fish.

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Loranthaceae family includes hemiparasitic members which are seen invading a wide range of commercial crops. Helicanthes elasticus (Desv.) Danser is very common on mango trees. Though parasitic in nature, this mistletoe is also medicinally important as fetoprotective, against vesicular calculi and kidney infections. This study is an attempt to document macro-microscopical features of parasitic root, fruit and host-mistletoe tissue interaction in the haustorium of H. elasticus growing on mango stems. Collection, preservation, sectioning, staining and photomicrography of the root, fruit and host-mistletoe union were done as per standard methodologies of anatomical studies. Though there is resemblance to the normal roots in morphology as well as anatomy, the microscopic finding of large number of branched stone cells in the roots is interesting. The morpho-anatomical features recorded would help in understanding the infection biology of this mistletoe. The eradication during the earlier stages of its establishment from seed or from the root creeping over the surface of the host can help in controlling this parasite infection on commercially important host plants.  相似文献   
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