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Magnetic materials were recently developed for sludge disposal because of their advantages. However, the role of magnetic materials in the process of anaerobic digestion of municipal dewatered sludge remains unclear. The aim of this present study is to investigate the magnetic effect factors such as static magnetic field, magnetic nanoparticles, and ordinary magnetic particles on the anaerobic digestion of municipal dewatered sludge. In addition, the biogas production variations and relevant physicochemical properties of municipal dewatered sludge under anaerobic digestion are also evaluated by adding anaerobic bacteria. Results indicated that the magnetic nanoparticles are superior to both ordinary magnetic particles and static magnetic field at total biogas production; moreover, the aerobic bacteria could shorten the duration of anaerobic digestion. For the sludge dewatering, the organic matter degradation rate, chemical oxygen demand degradation rate, and dewatering rate under the treatment condition with magnetic nanoparticles are 32.1%, 87.1%, and 70.9%, respectively. It is suggested that the magnetic nanoparticles are much suitable for sludge dewatering than ordinary magnetic particles. As combined with bacteria, magnetic nanoparticles can effectively increase gas output, methane content, and shorten the anaerobic digestion period. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 374–379, 2019 [ABSTRACT FROM AUTHOR]

Highlights • Blue light can promote elongation growth. • Blue light promotion of elongation growth is related to lower phytochrome activity. • Promoted elongation growth by blue light is one of shade-avoidance responses. Abstract To explore the action mode of blue light on elongation growth of bedding plants, the plant growth and morphology traits of petunia ( Petunia × hybrida , ‘Duvet Red’), calibrachoa ( Calibrachoa × hybrida , ‘Kabloom Deep Blue’), geranium ( Pelargonium × hortorum , ‘Pinto Premium Salmon’), and marigold ( Tagetes erecta , ‘Antigua Orange’) were compared under four light quality treatments: (1) R, “pure” red light (660 nm); (2) B, “pure” blue light (450 nm); (3) BR, “unpure” blue light created by mixing B with a low level of R to provide B/R ≈ 9; (4) BRF, “unpure” blue light created by adding a low level of far red light to BR with red/far red ≈ 1. Continuous (24-h) light-emitting diode lighting with either 100 or 50 μmol m−2 s−1 photosynthetic photon flux density at ≈ 23℃ was used with the above treatments. After 14–20 day of lighting treatment, B promoted elongation growth compared to R, as demonstrated by a greater canopy height, main stem length, internode length, and daily main stem extension rate. However, BR showed similar or inhibitory effects on these traits relative to R, while BRF exhibited similar promotion effects as B. The calculated phytochrome photoequilibrium, an indication of phytochrome activity, was higher for R (0.89) and BR (0.74) than for B (0.49) and BRF (0.63). Adding red (or far red) light reversed the effects of B (or BR) on elongation growth and the phytochrome photoequilibrium, suggesting that blue light promotion of elongation growth is related to the lower phytochrome activity. Also, B and BRF, when compared to R or BR, promoted elongation growth to a greater degree at 50 than 100 μmol m−2 s−1 for petunia and calibrachoa. In addition to the promoted elongation growth, B and BRF reduced side branch number, biomass allocation to side branches, leaf epinasty, leaf angle, and/or leaf chlorophyll content relative to R or BR, but increased individual leaf area, petiole length, and/or biomass allocation to main stem, which varied with different species. It suggests that the promoted elongation growth by blue light associated with lower phytochrome activity is one of shade-avoidance responses with varying sensitivity among species. [ABSTRACT FROM AUTHOR]

Objective: To heterologously produce the Shigella dysenteriae serotype 1 O-polysaccharide (O-PS, O-antigen) in Escherichia coli by transferring the minimum number of genes instead of the entire O-PS gene cluster.Results: The three glycosyltransferase genes (rfbR, rfbQ and rfp) responsible for the formation of the O-repeat unit were introduced into E. coli K-12 W3110 to synthesize S. dysenteriae 1 O-PS. The specific O-antigen ladder type with different chain lengths of O-repeat units was observed in the recombinant E. coli strain by SDS-PAGE silver staining and western blotting using S. dysenteriae 1 lipopolysaccharide antiserum. Analysis by mass spectrometry and ion chromatography suggested generation of the specific S. dysenteriae 1 O-repeat unit structure with an extra glucose residue attached.Conclusions: Recombinant E. coli expressing specific glycosyltransferase genes can generate the O-PS of S. dysenteriae 1 and might be able to synthesize heterologous O-antigens of various pathogenic bacteria for vaccine preparation. [ABSTRACT FROM AUTHOR]

N -Glycosyltransferase (NGT) is an inverting glycosyltransferase for an unusual pathway of N -linked protein glycosylation and glycosylates polypeptides in the consensus sequon (N-(X≠P)-T/S) with hexose monosaccharides. Here, we expressed and characterized a novel N -glycosyltransferase from Aggregatibacter aphrophilus (named AaNGT). RP-HPLC and Mass Spectrometry were used to assay and quantify glycopeptide formation by AaNGT and determine its substrate specificities. AaNGT could utilize a variety of nucleotide-activated sugar donors, including UDP-Glc, UDP-Gal, UDP-Xyl, GDP-Glc, dGDP-Glc and UDP-GlcN, to glycosylate the tested peptides. To the best of our knowledge, AaNGT was the first identified natural glycosyltransferase able to transfer GlcN moiety onto asparagine residues. AaNGT also exhibited a different position-specific residue preference of substrate peptides from the NGT of Actinobacillus pleuropneumoniae (ApNGT). In vitro assays with diverse synthesized peptides revealed that AaNGT preferred different peptide substrates from ApNGT. The efficient glycosylation of natural short peptides by AaNGT showed its potential to modify important therapeutic mammalian N -glycoproteins. [ABSTRACT FROM AUTHOR]

The development of a low-cost and high-performance electrode for water electrolysis is important for green energy development. In this paper, fluorine-based multi-halogen atom doped carbon quantum dot loaded vertical graphene electrodes are prepared using biomass waste vinasse as a carbon source. F and Cl co-doping has the best electrochemical properties among multi-halogen atom doping. The HER overpotentials of FCl-CQDs/VG at a current density of 10 mA cm−2 are 171 mV and 161 mV at 1 M KOH and 0.5 M H 2 SO 4 , and the OER overpotentials are 393 mV and 556 mV at 1 M KOH and 0.5 M H 2 SO 4 , respectively. The Faraday efficiencies of FCl-CQDs/VG are 89 % (HER) and 86.5 % (OER), respectively. Cl atom doping can increase the content of ionic and semi-ionic bonds C–F, accelerate charge transfer, and improve electrochemical performance. This study improves the basis and ideas for the development of low-cost and high-performance self-supported all-carbon electrodes. [Display omitted] • F-based multi-halogen atom doped vinasse-based all-carbon electrode prepared. • FCl-CQDs/VG has excellent performance and stability for overall water splitting. • Cl doping promotes charge transfer and electronic structure of ionic bond C–F. [ABSTRACT FROM AUTHOR]

Planetary transmission plays a vital role in wind turbine drivetrains, and its fault diagnosis has been an important and challenging issue. Owing to the complicated and coupled vibration source, time-variant vibration transfer path, and heavy background noise masking effect, the vibration signal of planet gear in wind turbine gearboxes exhibits several unique characteristics: Complex frequency components, low signal-to-noise ratio, and weak fault feature. In this sense, the periodic impulsive components induced by a localized defect are hard to extract, and the fault detection of planet gear in wind turbines remains to be a challenging research work. Aiming to extract the fault feature of planet gear effectively, we propose a novel feature extraction method based on spectral kurtosis and time wavelet energy spectrum (SK-TWES) in the paper. Firstly, the spectral kurtosis (SK) and kurtogram of raw vibration signals are computed and exploited to select the optimal filtering parameter for the subsequent band-pass filtering. Then, the band-pass filtering is applied to extrude periodic transient impulses using the optimal frequency band in which the corresponding SK value is maximal. Finally, the time wavelet energy spectrum analysis is performed on the filtered signal, selecting Morlet wavelet as the mother wavelet which possesses a high similarity to the impulsive components. The experimental signals collected from the wind turbine gearbox test rig demonstrate that the proposed method is effective at the feature extraction and fault diagnosis for the planet gear with a localized defect. [ABSTRACT FROM AUTHOR]

Triptolide (TRI) is an active diterpenoid lactone compound isolated from Tripterygium wilfordii,We focused on investigating the effect and mechanism of Triptolide (TRI) on liver injury. The toxic dose (LD50 = 100 μM) of TRI on liver Kupffer cells was explored, and network pharmacological analysis was performed to identify Caspase-3 as the target of TRI-induced liver injury. Regarding the pyroptosis research, we examined the level of TRI-induced pyroptosis in Kupffer cells, including inflammatory cytokine detection, protein assay, microscopic cell observation and LDH toxicity test. The effect of TRI on pyroptosis was assessed after knocking out GSDMD, GSDME and Caspase-3 in cells, respectively. We also investigated the liver injury-inducing action of TRI at the animal level. Our experimental results were consistent with those predicted by network pharmacology, indicating that TRI could bind to Caspase-3-VAL27 site to promote the cleavage of Caspase-3, and Cleaved-Caspase-3 induced pyroptosis of Kupffer cells through GSDME cleavage. GSDMD was not involved in TRI's action. TRI could promote Kupffer cell pyroptosis, elevate the inflammatory cytokine levels, and facilitate the expressions of N-GSDME and Cleaved-Capase 3. After the mutation of VAL27, TRI could not bind to Caspase-3. Animal-level results showed that TRI could induce liver injury in mice, while Caspase-3 knockout or Caspase-3 inhibitors could antagonize the action of TRI. We find that the TRI-induced liver injury occurs primarily through the Caspase-3-GSDME pyroptosis signal. TRI can promote Caspase − 3 maturation and regulate kupffer cell pyroptosis. The present findings offer a new idea for the safe use of TRI. • TRI can promote Caspase-3 maturation and regulate kupffer cell pyroptosis. • The binding of TRI, a Caspase-3 activator, to VAL27 site promoted the maturation and cleavage of Cleaved-Caspase-3. • TRI activated Caspase-3-GSDME in tissues and elevated the levels of N-GSDME and Cleaved-Caspase-3. [ABSTRACT FROM AUTHOR]