1,163 research outputs found
The effect of inflation on the morphology-derived rheological parameters of lava flows and its implications for interpreting remote sensing data - A case study on the 2014/2015 eruption at Holuhraun, Iceland
Асинхронный электропривод механизма передвижения козлового крана
Объектом исследования является электропривод двухдвигательный механизма козлового крана его передвижения. В процессе работы провели исследования электропривода двухдвигательного частотно-регулируемого. По результатам исследования была обоснована адекватность имитационных моделей, так же получены параметры настройки данной системы которая обеспечивает синхронизации скоростей при работе вращения двух приводов и при изменении нагрузки.Object of investigation is electric drive of two-motor mechanism of goat crane of its movement. In the process of operation, studies of electric drive of two-engine frequency-controlled were carried out. Based on the results of the study, the adequacy of simulation models was justified, as well as settings of this system were obtained, which provides synchronization of speeds during operation of rotation of two drives and at change of loa
Deeply sequenced metagenome and metatranscriptome of a biogas-producing microbial community from an agricultural production-scale biogas plant
Bremges A, Maus I, Belmann P, et al. Deeply sequenced metagenome and metatranscriptome of a biogas-producing microbial community from an agricultural production-scale biogas plant. GigaScience. 2015;4(1): 33.Background
The production of biogas takes place under anaerobic conditions and involves microbial decomposition of organic matter. Most of the participating microbes are still unknown and non-cultivable. Accordingly, shotgun metagenome sequencing currently is the method of choice to obtain insights into community composition and the genetic repertoire.
Findings
Here, we report on the deeply sequenced metagenome and metatranscriptome of a complex biogas-producing microbial community from an agricultural production-scale biogas plant. We assembled the metagenome and, as an example application, show that we reconstructed most genes involved in the methane metabolism, a key pathway involving methanogenesis performed by methanogenic Archaea. This result indicates that there is sufficient sequencing coverage for most downstream analyses.
Conclusions
Sequenced at least one order of magnitude deeper than previous studies, our metagenome data will enable new insights into community composition and the genetic potential of important community members. Moreover, mapping of transcripts to reconstructed genome sequences will enable the identification of active metabolic pathways in target organisms
Recommended from our members
Size distribution, mass concentration, chemical and mineralogical composition and derived optical parameters of the boundary layer aerosol at Tinfou, Morocco, during SAMUM 2006
During the SAMUM 2006 field campaign in southern Morocco, physical and chemical properties of desert aerosols
were measured. Mass concentrations ranging from 30μgm−3 for PM2.5 under desert background conditions up to
300 000μgm−3 for total suspended particles (TSP) during moderate dust storms were measured. TSP dust concentrations
are correlated with the local wind speed, whereasPM10 andPM2.5 concentrations are determined by advection from
distant sources. Size distributions were measured for particles with diameter between 20 nm and 500μm (parametrizations
are given). Two major regimes of the size spectrum can be distinguished. For particles smaller than 500 nm
diameter, the distributions show maxima around 80 nm, widely unaffected of varying meteorological and dust emission
conditions. For particles larger than 500 nm, the range of variation may be up to one order of magnitude and up to
three orders of magnitude for particles larger than 10μm. The mineralogical composition of aerosol bulk samples was
measured by X-ray powder diffraction. Major constituents of the aerosol are quartz, potassium feldspar, plagioclase,
calcite, hematite and the clay minerals illite, kaolinite and chlorite. A small temporal variability of the bulk mineralogical
composition was encountered. The chemical composition of approximately 74 000 particles was determined by
electron microscopic single particle analysis. Three size regimes are identified: for smaller than 500 nm in diameter, the
aerosol consists of sulphates and mineral dust. For larger than 500 nm up to 50μm, mineral dust dominates, consisting
mainly of silicates, and—to a lesser extent—carbonates and quartz. For diameters larger than 50μm, approximately
half of the particles consist of quartz. Time series of the elemental composition show a moderate temporal variability
of the major compounds. Calcium-dominated particles are enhanced during advection from a prominent dust source in
Northern Africa (Chott El Djerid and surroundings). The particle aspect ratio was measured for all analysed particles.
Its size dependence reflects that of the chemical composition. For larger than 500 nm particle diameter, a median aspect
ratio of 1.6 is measured. Towards smaller particles, it decreases to about 1.3 (parametrizations are given). From the
chemical/mineralogical composition, the aerosol complex refractive index was determined for several wavelengths
from ultraviolet to near-infrared. Both real and imaginary parts show lower values for particles smaller than 500 nm in
diameter (1.55–2.8 × 10−3i at 530 nm) and slightly higher values for larger particles (1.57–3.7 × 10−3i at 530 nm)
Discrete molecular dynamics simulations of peptide aggregation
We study the aggregation of peptides using the discrete molecular dynamics
simulations. At temperatures above the alpha-helix melting temperature of a
single peptide, the model peptides aggregate into a multi-layer parallel
beta-sheet structure. This structure has an inter-strand distance of 0.48 nm
and an inter-sheet distance of 1.0 nm, which agree with experimental
observations. In this model, the hydrogen bond interactions give rise to the
inter-strand spacing in beta-sheets, while the Go interactions among side
chains make beta-strands parallel to each other and allow beta-sheets to pack
into layers. The aggregates also contain free edges which may allow for further
aggregation of model peptides to form elongated fibrils.Comment: 15 pages, 8 figure
Compared to conventional, ecological intensive management promotes beneficial proteolytic soil microbial communities for agro-ecosystem functioning under climate change-induced rain regimes
Projected climate change and rainfall variability will affect soil microbial communities, biogeochemical cycling and agriculture. Nitrogen (N) is the most limiting nutrient in agroecosystems and its cycling and availability is highly dependent on microbial driven processes. In agroecosystems, hydrolysis of organic nitrogen (N) is an important step in controlling soil N availability. We analyzed the effect of management (ecological intensive vs. conventional intensive) on N-cycling processes and involved microbial communities under climate change-induced rain regimes. Terrestrial model ecosystems originating from agroecosystems across Europe were subjected to four different rain regimes for 263 days. Using structural equation modelling we identified direct impacts of rain regimes on N-cycling processes, whereas N-related microbial communities were more resistant. In addition to rain regimes, management indirectly affected N-cycling processes via modifications of N-related microbial community composition. Ecological intensive management promoted a beneficial N-related microbial community composition involved in N-cycling processes under climate change-induced rain regimes. Exploratory analyses identified phosphorus-associated litter properties as possible drivers for the observed management effects on N-related microbial community composition. This work provides novel insights into mechanisms controlling agro-ecosystem functioning under climate change
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