Experimental Investigation on Flexural Properties of Natural Fiber and Synthetic Fiber Composites

The use of natural fibers in polymer matrices is highly beneficial because the strength and toughness of these composites resulting are greater than those of the unreinforced plastics. The main objective of present work is to investigate the mechanical properties of BANANA fiber polyester resin composites at different weight fractions and carbon fiber polyester resin composites at different weight fractions. Tested specimens of composites were fabricated according to the standards using hand moulding method. The developed composites were then tested to evaluate their Flexural properties. It was found that the increment in fiber content in composites increases the mechanical properties. The mechanical properties of BANANA fiber composites compared with CARBON fiber composites. However, CARBON based composites exhibited better Flexural properties than BANANA based composites

Effects of solar eclipse on photosynthesis of Portulaca oleracea and Phyla nodiflora in coastal wild conditions

The total solar eclipse provided a unique opportunity to understand the effects of solar radiation on the biosphere. The present study attempts to record meteorological parameters and to compare chlorophyll contents of Portulaca oleracea and Phyla nodiflora in coastal wild conditions during total solar eclipse on July 22, 2009.  Changes in meteorological parameters such as temperature by 0.5ËšC, relative humidity by 4% and light intensity around 100 lux were set to be low during eclipse day when compared to that of corresponding week. Minor changes were also observed in the wind speed and direction during solar eclipse day.  Mature leaves of Portulaca oleracea and Phyla nodiflora from coastal wild conditions were collected and analysed for total chlorophyll, chlorophyll a, chlorophyll b and carotinoid contents at various time intervals during solar eclipse day and previous days. Chlorophyll levels were decreased slightly during solar eclipse day, whereas carotinoid levels were increased marginally in both the plant species.  Solar radiation and its photochemical phases during eclipse day are responsible for the observed reduction in photosynthetic rates of wild plants

Disruption of Yarrowia lipolytica biofilms by rhamnolipid biosurfactant

BACKGROUND: Yarrowia lipolytica is an ascomycetous dimorphic fungus that exhibits biofilm mode of growth. Earlier work has shown that biosurfactants such as rhamnolipids are efficient dispersants of bacterial biofilms. However, their effectiveness against fungal biofilms (particularly Y. lipolytica) has not been investigated. The aim of this study was to determine the effect of rhamnolipid on a biofilm forming strain of Y. lipolytica. Two chemical surfactants, cetyl-trimethyl ammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) were used as controls for comparison. RESULTS: The methylene blue dye exclusion assay indicated an increase in fungal cell permeability after rhamnolipid treatment. Microtiter plate assay showed that the surfactant coating decreased Y. lipolytica biofilm formation by 50%. Rhamnolipid treatment disrupted pre-formed biofilms in a more effective manner than the other two surfactants. Confocal laser scanning microscopic studies showed that biofilm formation onto glass surfaces was decreased by 67% after sub-minimum inhibitory concentration (sub-MIC) treatment with rhamnolipids. The disruption of biofilms after rhamnolipid treatment was significant (P<0.05) when compared to SDS and CTAB. CONCLUSION: The results indicate a potential application of the biological surfactant to disrupt Y. lipolytica biofilms

Hormetic effect of ionic liquid 1-ethyl-3-methylimidazolium acetate on bacteria

h i g h l i g h t s Among three ILs tested, only [EMIM

A New Reporter Vector System Based on Flow-Cytometry to Detect Promoter Activity

In this study, we report the development of a new dual reporter vector system for the analysis of promoter activity. This system employs green fluorescence emitting protein, EGFP, as a reporter, and uses red fluorescence emitting protein, DsRed, as a transfection control in a single vector. The expression of those two proteins can be readily detected via flow cytometry in a single analysis, with no need for any further manipulation after transfection. As this system allows for the simultaneous detection of both the control and reporter proteins in the same cells, only transfected cells which express the control protein, DsRed, can be subjected to promoter activity analysis, via the gating out of all un-transfected cells. This results in a dramatic increase in the promoter activity detection sensitivity. This novel reporter vector system should prove to be a simple and efficient method for the analysis of promoter activity

Validation of a quantitative image analysis methodology for the assessment of the morphology and structure of aerobic granular sludge in the presence of pharmaceutically active compounds

Aerobic granular sludge is considered a promising technology for biological wastewater treatment, since it is more compact and resistant to shock and toxic loads than activated sludge systems. Furthermore, the monitoring of the aerobic granules structure, size and morphology has been growing in importance, proving to be suitable for operational and process control purposes. In this work, a sampling methodology is validated for the assessment of the ensemble granular and floccular biomass, by quantitative image analysis, in the presence of pharmaceutically active compounds, including 17?-estradiol and 17?-ethinylestradiol and the sulfamethoxazole. The employed sampling volumes were found to be adequate in obtaining a representative number of granules for all samples. Indeed, it was always obtained a variation lower than 5% in the average and standard deviation criterion of the main size, morphological and structural parameters. Moreover, it was also assessed the performance of the sieving process in successfully separating the granular and floccular biomass fractions and established a lower bound fraction size cut-off for the employed sieve. In addition, the continuity of the performed methodology and the image acquisition triplicates approach could also be validated. The ability of the proposed QIA procedure to monitor the studied AGS system was corroborated by the fact that 95% of the samples were able to be classified in the correct group (proof of concept).The authors wish to thank the company Águas do Tejo Atlântico for supplying the aerobic granular sludge. The authors also thank the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469 unit and the project AGeNT - PTDC/BTA-BTA/31264/2017 (POCI-01-0145-FEDER-031264). Cristiano Leal is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. A. Val del Rio is supported by Xunta de Galicia, Spain (ED418B 2017/075) and program Iacobus (2018/2019).info:eu-repo/semantics/publishedVersio

A comparison of fate and toxicity of selenite, biogenically, and chemically synthesized selenium nanoparticles to zebrafish (Danio rerio) embryogenesis

Conservation Biolog

Efficient Gene Transfer in Bacterial Cell Chains

Horizontal gene transfer contributes to evolution and the acquisition of new traits. In bacteria, horizontal gene transfer is often mediated by conjugative genetic elements that transfer directly from cell to cell. Integrative and conjugative elements (ICEs; also known as conjugative transposons) are mobile genetic elements that reside within a host genome but can excise to form a circle and transfer by conjugation to recipient cells. ICEs contribute to the spread of genes involved in pathogenesis, symbiosis, metabolism, and antibiotic resistance. Despite its importance, little is known about the mechanisms of conjugation in Gram-positive bacteria or how quickly or frequently transconjugants become donors. We visualized the transfer of the integrative and conjugative element ICEBs1 from a Bacillus subtilis donor to recipient cells in real time using fluorescence microscopy. We found that transfer of DNA from a donor to a recipient appeared to occur at a cell pole or along the lateral cell surface of either cell. Most importantly, we found that when acquired by 1 cell in a chain, ICEBs1 spread rapidly from cell to cell within the chain by additional sequential conjugation events. This intrachain conjugation is inherently more efficient than conjugation that is due to chance encounters between individual cells. Many bacterial species, including pathogenic, commensal, symbiotic, and nitrogen-fixing organisms, harbor ICEs and grow in chains, often as parts of microbial communities. It is likely that efficient intrachain spreading is a general feature of conjugative DNA transfer and serves to amplify the number of cells that acquire conjugative mobile genetic elements

Delineation of cellular stages and identification of key proteins for reduction and biotransformation of Se(IV) by Stenotrophomonas bentonitica BII-R7

This work was supported by the grants obtained by M.P-C: (FPU 15/04284; "Formacion de Profesorado Universitario") and EST 18/00610 ("Ayudas a la movilidad para estancias breves y traslados temporales") from Spanish Ministry (Ministerio de Universidades) . Funding was also provided by grants CGL2014-59616-R; RTI2018.101548.B.I00 to M.L. M. Funding for open access charge: University of Granada/CBUA. The authors thank Concepcion Hernandez-Castillo and Maria del Mar Abad Ortega for their assistance with microscopy at the University of Granada ("Centro de Instrumentacion Cientifica") . We also thank Dr. Kenneth McCreath for editorial support.The widespread use of selenium (Se) in technological applications (e.g., solar cells and electronic devices) has led to an accumulation of this metalloid in the environment to toxic levels. The newly described bacterial strain Stenotrophomonas bentonitica BII-R7 has been demonstrated to reduce mobile Se(IV) to Se(0)-nanoparticles (Se(0) NPs) and volatile species. Amorphous Se-nanospheres are reported to aggregate to form crystalline nanostructures and trigonal selenium. We investigated the molecular mechanisms underlying the biotransformation of Se(IV) to less toxic forms using differential shotgun proteomics analysis of S. bentonitica BII-R7 grown with or without sodium selenite for three different time-points. Results showed an increase in the abundance of several proteins involved in Se(IV) reduction and stabilization of Se(0)NPs, such as glutathione reductase, in bacteria grown with Se(IV), in addition to many proteins with transport functions, including RND (resistance-nodulationdivision) systems, possibly facilitating Se uptake. Notably proteins involved in oxidative stress defense (e.g., catalase/peroxidase HPI) were also induced by Se exposure. Electron microscopy analyses confirmed the biotransformation of amorphous nanospheres to trigonal Se. Overall, our results highlight the potential of S. bentonitica in reducing the bioavailability of Se, which provides a basis both for the development of bioremediation strategies and the eco-friendly synthesis of biotechnological nanomaterials.Spanish Ministry (Ministerio de Universidades) FPU 15/04284 EST 18/00610University of Granada/CBUACGL2014-59616-R RTI2018.10154