397 research outputs found
Diagnosis of tidal turbine vibration data through deep neural networks
Tidal power is an emerging field of renewable energy, harnessing the power of regular and predictable tidal currents. However, maintenance of submerged equipment is a major challenge. Routine visual inspections of equipment must be performed onshore, requiring the costly removal of turbines from the sea bed and resulting in long periods of downtime. The development of condition monitoring techniques providing automated fault detection can therefore be extremely beneficial to this industry, reducing the dependency on inspections and allowing maintenance to be planned efficiently. This paper investigates the use of deep learning approaches for fault detection within a tidal turbine's generator from vibration data. Training and testing data were recorded over two deployment periods of operation from an accelerometer sensor placed within the nacelle of the turbine, representing ideal and faulty responses over a range of operating conditions. The paper evaluates a deep learning approach through a stacked autoencoder network in comparison to feature-based classification methods, where features have been extracted over varying rotation speeds through the Vold-Kalma filter
Beyond Plague Pits: Using Genetics to Identify Responses to Plague in Medieval Cambridgeshire
The hSNM1 protein is a DNA 5′-exonuclease
The human SNM1 protein is a member of a highly conserved group of proteins catalyzing the hydrolysis of nucleic acid substrates. Although overproduction is unstable in mammalian cells, we have overproduced a recombinant hSNM1 protein in an insect cell system. The protein is a single-strand 5′-exonuclease, like its yeast homolog. The enzyme utilizes either DNA or RNA substrates, requires a 5′-phosphate moiety, shows very little activity on double-strand substrates, and functions at a size consistent with a monomer. The exonuclease activity requires the conserved β-lactamase domain; site-directed mutagenesis of a conserved aspartate inactivates the exonuclease
Modulating the Properties of Azulene‐Containing Polymers through Controlled Incorporation of Regioisomers
Two libraries of random conjugated polymers are presented that incorporate varying ratios of regioisomeric azulene units connected via the 5‐membered or 7‐membered ring in combination with bithiophene or fluorene comonomers. It is demonstrated that the optoelectronic and stimuli‐responsive properties of the materials can be systematically modulated by tuning the relative percentage of each azulene building block in the polymer backbone. Significantly, these materials exhibit stimuli‐responsive behavior in the solid state with spin‐coated thin films undergoing rapid and reversible color switching. Ultimately, this work introduces a new design strategy in which the optoelectronic properties of conjugated polymers can be modulated by varying only the regiochemistry of the constituent building blocks along a polymer chain
Tuberculosis before and after the Black Death (1346 – 1353 CE) in the Hospital of St John the Evangelist in Cambridge, England
This article was published with Open Access under the Elsevier/Jisc Open Access agreement The authors would like to thank all of the members of the ‘After the Plague’ project, and the Cambridge Archaeological Unit for their help and support. We would also like to thank György Pálfi for organising the ICEPT-3 conference, at which the initial findings of this research were presented and for inviting us to contribute to this special issue. This research was funded by the Wellcome Trust (Award no 2000368/Z/15/Z) and St John's College, Cambridge.Peer reviewedPublisher PD
A One-Step Strategy for End-Functionalized Donor–Acceptor Conjugated Polymers
A modular and robust method for preparing end-functionalized donor–acceptor (D–A) narrow bandgap conjugated polymers is reported that avoids multistep reactions and postpolymerization modification. The strategy is well-controlled and affords functional materials with predictable molecular weight and high end-group fidelity. To exemplify this synthetic strategy, narrow bandgap conjugated polymers based on PDPP2FT were prepared that contain perylene diimide (PDI) units at the chain-ends. Monte Carlo simulations confirm the high degree of chain-end functionalization while photoluminescence studies reveal the unique photophysical properties of the end-functional polymers with efficient charge transfer occurring between the main polymer chain and PDI end-groups that results exclusively from their covalent linkage
PEGylation of polypropylenimine dendrimers: effects on cytotoxicity, DNA condensation, gene delivery and expression in cancer cells
Diaminobutyric polypropylenimine (DAB) dendrimers have been shown to be highly efficient non-viral gene delivery systems for cancer therapy. However, their cytotoxicity currently limits their applications. To overcome this issue, PEGylation of DAB dendrimer, using various PEG molecular weights and dendrimer generations, has been attempted to decrease the cytotoxicity and enhance the DNA condensation, size and zeta potential, cellular uptake and transfection efficacy of these dendriplexes. Among all the PEGylated dendrimers synthesized, generation 3- and generation 4-DAB conjugated to low molecular weight PEG (2 kDa) at a dendrimer: DNA ratio of 20:1 and 10:1 resulted in an increase in gene expression on almost all tested cancer cells lines (by up to 3.2-fold compared to unmodified dendrimer in A431 cells). The highest level of β-galactosidase gene expression (10.07 × 10−3 ± 0.09 × 10−3 U/mL) was obtained following treatment of B16F10-Luc cells with G4-dendrimer PEGylated with PEG2K at a dendrimer: DNA ratio of 20:1. These delivery systems significantly decreased cytotoxicity on B16F10-Luc cells, by more than 3.4-fold compared to unmodified dendrimer. PEGylated generations 3- and 4-DAB dendrimers are therefore promising gene delivery systems for cancer therapy, combining low cytotoxicity and high transfection efficacy
Pushing the Limits for Thiol−Ene and CuAAC Reactions: Synthesis of a 6th Generation Dendrimer in a Single Day
Dendrimer synthesis should not be tedious and time-consuming. By utilizing an AB2−CD2 approach and having orthogonal, “clickable” groups on each monomer, the time for dendrimer assembly can be drastically reduced. This was shown by preparation of a sixth generation dendrimer from starting monomer units in a single day
A large potentiation effect of serum on the in vitro potency of tulathromycin against Mannheimia haemolytica and Pasteurella multocida
The antimicrobial properties of tulathromycin were investigated for M.haemolytica and P.multocida. Three invitro indices of antimicrobial activity, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill curves, were established for six isolates of each organism. Each index was measured in two growth media: Mueller-Hinton broth (MHB) and calf serum. It was shown that MICs and MBCs were markedly lower in serum than in MHB. MHB:serum ratios for MIC were 47:1 (M.haemolytica) and 53:1 (P.multocida). For both serum and MHB, adjustment of pH led to greater potency at alkaline compared to acid pH. Tulathromycin MIC was influenced by size of inoculum count, being 4.0- to 7.7-fold greater for high compared to low initial counts. It was concluded that for the purpose of determining dosages for therapeutic use, pharmacodynamic data for tulathromycin should be derived in biological fluids such as serum. It is hypothesized that invitro measurement of MIC in broth, conducted according to internationally recommended standards, may be misleading as a basis for estimating the invivo potency of tulathromycin
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