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Plasmonics - Effect of different gold (Au) grating structures on light absorption in solar cell is investigated by finite elemental analysis using COMSOL multiphysics-RF module. The geometry of the...  相似文献   
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Plasmonics - This article explores the effect of sensing performances with subject to change in different types of material and this study is carried out by the support of plasmon-coated photonic...  相似文献   
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ObjectiveMaize is an important crop for fodder, food and feed industry. The present study explores the plant-microbe interactions as alternative eco-friendly sustainable strategies to enhance the crop yield.MethodologyBacterial diversity was studied in the rhizosphere of maize by culture-dependent and culture-independent techniques by soil sampling, extraction of DNA, amplification of gene of interest, cloning of desired fragment and library construction.ResultsCulturable bacteria were identified as Achromobacter, Agrobacterium, Azospirillum, Bacillus, Brevibacillus, Bosea, Enterobacter, Microbacterium, Pseudomonas, Rhodococcus, Stenotrophomonas and Xanthomonas genera. For culture-independent approach, clone library of 16S ribosomal RNA gene was assembled and 100 randomly selected clones were sequenced. Majority of the sequences were related to Firmicutes (17%), Acidobacteria (16%), Actinobacteria (17%), Alpha-Proteobacteria (7%), Delta-proteobacteria (4.2%) and Gemmatimonadetes (4.2%) However, some of the sequences (30%) were novel that showed no homologies to phyla of cultured bacteria in the database. Diversity of diazotrophic bacteria in the rhizosphere investigated by analysis of PCR-amplified nifH gene sequence that revealed abundance of sequences belonging to genera Azoarcus (25%), Aeromonas (10%), Pseudomonas (10%). The diazotrophic genera Azotobacter, Agrobacterium and Zoogloea related nifH sequences were also detected but no sequence related to Azospirillum was found showing biasness of the growth medium rather than relative abundance of diazotrophs in the rhizosphere.ConclusionThe study provides a foundation for future research on focussed isolation of the Azoarcus and other diazotrophs found in higher abundance in the rhizosphere.  相似文献   
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  • High temperature induces several proteins in plants that enhance tolerance to high temperature shock. The fate of proteins synthesised in microbial cells or secreted into culture media by interacting microbes has not been fully elucidated. The present investigation aimed to characterise plant growth‐promoting rhizobacteria (PGPR) isolated from the rhizosphere of wheat genotypes (differing in tolerance to high temperature stress) and evaluate their performance as bioinoculant for use in wheat.
  • Four bacterial strains, viz. Pseudomonas brassicacearum, Bacillus thuringiensis, Bacillus cereus strain W6 and Bacillus subtilis, were isolated from the rhizosphere of heat‐stressed and unstressed wheat genotypes. The wheat genotypes were exposed to high temperature stress at 45 °C for 10 days (3 h daily) at pre‐anthesis phase. Isolates were identified on the basis of morphology and biochemical characteristics, 16S rRNA gene sequencing and whole cell protein profiles. Results were further complemented by size exclusion chromatography (SEC) with fast protein liquid chromatography (FPLC) and SDS PAGE of 80% ammonium sulphate precipitates of the cell‐free supernatants.
  • Isolates were positive for catalase, oxidases and antimicrobial activity . P. brassicacearum from the rhizosphere of the heat‐tolerant genotype was more efficient in phosphate solubilisation, bacteriocin production, antifungal and antibacterial activity against Helminthosporium sativum, Fusarium moniliforme and Klebsiella pneumonia, respectively. The inoculated seedlings had significantly higher root and shoot fresh weight, enhanced activity of antioxidant enzymes, proline and protein content. Total profiling of the culture with SDS‐PAGE indicated expression of new protein bands in 95 kDa in P. brassicacearum.
  • Temperature‐induced changes in PGPR isolates are similar to those in the host plant. P. brassicacearum may be a good candidate for use in biofertiliser production for plants exposed to high temperature stress.
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Background

In recent years, microalgae (MA) have attracted much interest considering their possible therapeutic application. They contain active natural compounds or derivatives (extracts, pure or chemically modified compounds) that have increasing applications in the pharmaceutical industry.

Methods

The present study aims to examine microalgae for new photosensitizers, with a potential to be used in the light-associated treatment of tumors. Semi-purified extracts of several microalgae strains were evaluated as photosensitizers for photodynamic therapy (PDT) applications. Four tumor cell lines (A549, LNCap, MCF-7, and MDA-MB 435) were used to assess 34 samples extracted by three methods: cellulase enzyme, lysozyme enzyme and ultra-sonication. The fluorescence measurements and the recorded images alongside the spectral intensities between 650–800 nm wavelengths provided characteristic features to some of the contents of the examined extracts.

Results

Several microalgae constituents activated by blue light (BL), red light (RL) or both (in sequence) exhibited significant effects on the viability of the tumor cell lines, decreasing it as much as 95% for certain MA constituents. Majority of the MA constituents showed a higher phototoxicity after exposure to both blue and red lights than the photo-induced toxicity when exposed to a single light source. The viability of the tumor cells exhibited the dose dependent response with the MA constituents.

Conclusion

The results clearly showed that MA constituents are potential photosensitizers that have a significant photo-damage effects on the tested cancer cells.  相似文献   
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