73 research outputs found

    Biogas Production From a Mixture of Cow Manure with Chicken Manure

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    Biogas technology with zero waste concept is expected to be the alternative energy and to reduce environmental problems. The purpose of this study is to know the biogas yield per kilogram of each chicken and cow manure comparison. The study was conducted in six treatments with the addition of chicken manure of 0, 100, 300, 500, 700 and 1000 grams. The fermentation process is done using a batch system and biogas measurement was taken daily. The parameters to be observed were organic matter, the degree of acidity (pH), temperature, volume of biogas, biogas productivity, and C / N ratio of each treatment. The results showed that the overall pH at the beginning and end of the study tend to be close to neutral. The highest biogas yield was resulted from a mixture of chicken manure and cow manure at the composition of 1:1 or 50%:50% with biogas total amount of 35.690 ml and biogas productivity of 0,33 liters/g (volatile solid)

    Novel drug targets in cell wall biosynthesis exploited by gene disruption in Pseudomonas aeruginosa

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    © 2017 Elamin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. For clinicians, Pseudomonas aeruginosa is a nightmare pathogen that is one of the top three causes of opportunistic human infections. Therapy of P. aeruginosa infections is complicated due to its natural high intrinsic resistance to antibiotics. Active efflux and decreased uptake of drugs due to cell wall/membrane permeability appear to be important issues in the acquired antibiotic tolerance mechanisms. Bacterial cell wall biosynthesis enzymes have been shown to be essential for pathogenicity of Gram-negative bacteria. However, the role of these targets in virulence has not been identified in P. aeruginosa. Here, we report knockout (k.o) mutants of six cell wall biosynthesis targets (murA, PA4450; murD, PA4414; murF, PA4416; ppiB, PA1793; rmlA, PA5163; waaA, PA4988) in P. aeruginosa PAO1, and characterized these in order to find out whether these genes and their products contribute to pathogenicity and virulence of P. aeruginosa. Except waaA k.o, deletion of cell wall biosynthesis targets significantly reduced growth rate in minimal medium compared to the parent strain. The k.o mutants showed exciting changes in cell morphology and colonial architectures. Remarkably, ΔmurF cells became grossly enlarged. Moreover, the mutants were also attenuated in vivo in a mouse infection model except ΔmurF and ΔwaaA and proved to be more sensitive to macrophage-mediated killing than the wild-type strain. Interestingly, the deletion of the murA gene resulted in loss of virulence activity in mice, and the virulence was restored in a plant model by unknown mechanism. This study demonstrates that cell wall targets contribute significantly to intracellular survival, in vivo growth, and pathogenesis of P. aeruginosa. In conclusion, these findings establish a link between cell wall targets and virulence of P. aeruginosa and thus may lead to development of novel drugs for the treatment of P. aeruginosa infection

    Phylogenetic placement of environmental sequences using taxonomically reliable databases helps to rigorously assess dinophyte biodiversity in Bavarian lakes (Germany).

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    1. Reliable determination of organisms is a prerequisite to explore their spatial and temporal occurrence and to study their evolution, ecology, and dispersal. In Europe, Bavaria (Germany) provides an excellent study system for research on the origin and diversification of freshwater organisms including dinophytes, due to the presence of extensive lake districts and ice age river valleys. Bavarian freshwater environments are ecologically diverse and range from deep nutrient‐poor mountain lakes to shallow nutrient‐rich lakes and ponds. 2. We obtained amplicon sequence data (V4 region of small subunit‐rRNA, c. 410 bp long) from environmental samples collected at 11 sites in Upper Bavaria. We found 186 operational taxonomic units (OTUs) associated with Dinophyceae that were further classified by means of a phylogenetic placement approach. 3. The maximum likelihood tree inferred from a well‐curated reference alignment comprised a systematically representative set of 251 dinophytes, covering the currently known molecular diversity and OTUs linked to type material if possible. Environmental OTUs were scattered across the reference tree, but accumulated mostly in freshwater lineages, with 79% of OTUs placed in either Apocalathium, Ceratium, or Peridinium, the most frequently encountered taxa in Bavaria based on morphology. 4. Twenty‐one Bavarian OTUs showed identical sequences to already known and vouchered accessions, two of which are linked to type material, namely Palatinus apiculatus and Theleodinium calcisporum. Particularly within Peridiniaceae, delimitation of Peridinium species was based on the intraspecific sequence variation. 5. Our approach indicates that high‐throughput sequencing of environmental samples is effective for reliable determination of dinophyte species in Bavarian lakes. We further discuss the importance of well‐curated reference databases that remain to be developed in the future

    LEICHTER: Innovativer Leichtbau durch energiereduziertes Fuegen mit Lasersystemen neuester Generation Abschlussbericht

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    SIGLEAvailable from TIB Hannover: F03B545 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman
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