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A methodology to include flow-acoustic interactions in a Helmholtz solver is proposed and used to quantify their impact on the thermoacoustic modes of a real industrial combustor. This methodology takes advantage of the compactness of flow-acoustic interactions, modeling the regions of interest by 2Ã--2 matrices included in the Helmholtz computation thanks to a dedicated boundary condition. The one-dimensional formulation introduced in Ni et al. ("Accounting for Acoustic Damping in a Helmholtz Solver," AIAA Journal, Vol. 55, No. 4, 2017, pp. 1205-1220) is extended to three-dimensional configurations so that the dissipation of dilution holes, swirlers, and perforated plates can be accounted for. The potential of the method is illustrated by performing the thermoacoustic analysis of an annular combustor from SAFRAN. The Helmholtz solution corresponding to an azimuthal mode is analyzed and shows that flow-acoustic interactions dissipate an important part of the acoustic energy but also limit the amplification created by the flame. [ABSTRACT FROM AUTHOR]

In distribution networks, the lack of measurement data is usually thought to be an inevitable bottleneck of conventional grid operation and planning. Recently, the availability of smart meters in the distribution network has provided an opportunity to improve the network observability. In medium-voltage (MV) distribution networks, there is an increasing demand to use aggregated smart meter data for the state estimation, instead of adopting pseudo-measurements with a low level of accuracy. However, the performance of an estimator requires good knowledge of the available measurements, in terms of both expected values and associated uncertainties. Therefore, this paper intends to firstly pave a new way of utilizing smart meter data gathered from the low-voltage (LV) feeders in a concrete and reliable manner. For the purpose of state estimation in MV distribution networks, smart meter data is to be processed through three steps: phase identification, data aggregation and uncertainty evaluation. The feasibility of the proposed method is verified on the IEEE European LV Test Feeder with a set of real-world smart meter data. Afterwards, the influence of the aggregated smart meter data on the three-phase state estimation are investigated on the modified IEEE 13-node test system and IEEE 34-node test system. Simulation results show that the effect of aggregated smart meter data on the accuracy of state estimators is dependent on both the accuracy level of the aggregated data and the measurement configuration in the network. Furthermore, the use of aggregated smart meter data is shown to be able to provide improved state estimation. [ABSTRACT FROM AUTHOR]

Thermoacoustic Helmholtz solvers provide a cheap and efficient way of predicting combustion instabilities. However, because they rely on the inviscid Euler equations at zero Mach number, they cannot properly describe the regions where aerodynamics may interact with acoustic waves, in the vicinity of dilution holes and injectors, for example. A methodology is presented to incorporate the effect of non-purely acoustic mechanisms into a three-dimensional thermoacoustic Helmholtz solver. The zones where these mechanisms are important are modeled as two-port acoustic elements, and the corresponding matrices, which notably contain the dissipative effects due to acoustic-hydrodynamic interactions, are used as internal boundary conditions in the Helmholtz solver. The rest of the flow domain, where dissipation is negligible, is solved by the classical Helmholtz equation. With this method, the changes in eigenfrequency and eigenmode structure introduced by the acoustic-hydrodynamic effects are captured, while keeping the simplicity and efficiency of the Helmholtz solver. The methodology is successfully applied on an academic configuration, first with a simple diaphragm, then with an industrial swirler, with matrices measured from experiments and large-eddy simulation. [ABSTRACT FROM AUTHOR]

Kawasaki disease ( KD) is a type of systemic vasculitis syndrome related to immune dysfunction. Previous studies have implicated that dysfunctional regulatory T cells ( Treg) may be associated with the immune dysfunction in KD. In the absence of micro RNAs (mi RNAs), forkhead box protein 3 ( FoxP3)+ Treg develop but fail to maintain immune homeostasis. This study was designed to investigate the effects of mi R-155, mi R-21 and mi R-31 on Treg in children with KD. The proportions of CD4+ CD25+ FoxP3+ Treg and the mean fluorescence intensity ( MFI) of phosphorylated-signal transducer and activator of transcription ( pSTAT)-5 and pSTAT-3 protein in CD4+ CD25+ Treg were analysed by flow cytometry. The concentration of interleukin ( IL)-6 in plasma was measured by cytometric bead array. Real-time polymerase chain reaction was performed to detect the levels of micro RNAs and associated factors in CD4+ CD25+ Treg. The proportion of Treg and the mRNA levels of the associated factors [ FoxP3, glucocorticoid-induced tumour necrosis factor-receptor ( GITR), cytotoxic T lymphocyte antigen (CTLA)-4)] were significantly lower in KD patients ( P < 0·05). MiR-155 and mi R-21 levels were significantly down-regulated and mi R-31 expression was higher in KD patients ( P < 0·05). Plasma interleukin ( IL)-6 concentrations, pSTAT-3 protein levels and suppressors of cytokine signalling ( SOCS)-1 mRNA expression were remarkably elevated in acute KD ( P < 0·05), while pSTAT-5 protein levels were remarkably decreased in acute KD ( P < 0·05). These findings were reversed after intravenous immunoglobulin treatment ( P < 0·05). Our results demonstrate that FoxP3 mRNA levels were primarily affected by the mi R-155/ SOCS1 and the mi R-31 signalling pathways. These results suggest that the decrease in FoxP3+ Treg might be associated with decreased expression of mi R-155, leading to aberrant SOCS1/ STAT-5 signalling and overexpression of mi R-31 in patients with acute KD. [ABSTRACT FROM AUTHOR]

Pavement segments are functionally interdependent under traffic equilibrium, leading to interdependent maintenance and rehabilitation (M&R) decisions for different segments, but it has not received significant attention in the pavement management community yet. This study developed a maintenance optimization model for interdependent pavement networks based on the simultaneous network optimization (SNO) framework and a multi‐agent reinforcement learning algorithm. The established model was demonstrated on a highway pavement network in the real‐world, compared to a previously built two‐stage bottom‐up (TSBU) model. The results showed that, compared to TSBU, SNO produced a 3.0% reduction in total costs and an average pavement performance improvement of up to 17.5%. It prefers concentrated M&R schedules and tends to take more frequent preventive maintenance to reduce costly rehabilitation. The results of this research are anticipated to provide practitioners with quantitative estimates of the possible impact of ignoring segment interdependencies in M&R planning. [ABSTRACT FROM AUTHOR]

The Ohno continuous casting process is being used regularly in the unidirectional crystallisation of high purity copper and silver wires for electronics applications. Many experimental investigations have been carried out on both fundamental and practical aspects of the process. This paper deals with the feasibility of a one-dimensional heat transfer approach for the analysis of the effect of the crucial processing parameters. The results on the effects of varying the parameters based on the calculation of the temperature profiles along the axis of the cast rod were in accord with the experimental results in the literature, indicating that the one-dimensional approach can be used as an analytical tool for the process. [ABSTRACT FROM AUTHOR]

Abstract: A novel κ‐carrageenase gene (CgkB) has been cloned from Pedobacter hainanensis NJ‐02 and expressed heterologously in Escherichia coli BL21 (DE3). It consisted of 1935 bp and encoded 644 amino acid residues with a molecular weight of 71·61 kDa. The recombinant enzyme showed maximal activity of 2458 U mg−1 at 40°C and pH 8·0. Additionally, it could retain more than 70% of its maximal activity after being incubated at pH of 5·5–10·0 below 40°C. K+ and a broad range of NaCl can activate the enzyme. The Km and Vmax of CgkB was 2·4 mg ml−1 and 126 mmol mg−1 min−1. The ESI‐MS analysis of hydrolysates indicated that the enzyme can endolytically depolymerize the carrageenan into tetrasaccharides and hexasaccharides. The results indicated that the enzyme with high activity could be a valuable enzyme tool to produce carrageenan oligosaccharides with various activities. Significance and Impact of the Study: Enzymatic preparation of carrageenan oligosaccharides has drawn increased attention due to their various physiological activities. It is urgent to explore enzyme tools with higher activity and better stability. In this work, a novel κ‐carrageenase was identified and characterized from marine bacterium Pedobacter hainanensis NJ‐02. The enzyme with high activity could be a valuable tool to produce carrageenan oligosaccharides with various activities [ABSTRACT FROM AUTHOR]

Abstract: A 35 amino acid residue peptide corresponding to the N-terminal subdomain of the granulin-like repeat from rice oryzain β was synthesized and regioselectively oxidized to produce a species with a [1–3, 2–4] disulfide-pairing pattern. The resulting peptide was studied in solution using NMR and was shown to adopt the tertiary topology of a stack of two β-hairpins found in the emerging family of granulin-like growth factors. Because of the longer second β-hairpin, the overall conformation of the peptide is somewhat more flexible than that of its well-structured carp granulin-1 analog. Except for the cysteine alignment, there is very little sequence homology between granulin-like growth factors from the animal kingdom and the granulin-like repeats at the C-termini of plant cysteine proteases. Therefore, the stack of two β-hairpins may be a conserved three-dimensional organization of the granulin-like repeats from evolutionary distant sources with a significant role in specific protein–protein interactions. [ABSTRACT FROM AUTHOR]

Separation of squalene, a type of terpenoid hydrocarbons with important biological properties, from camellia oil by silver ion complexation was studied. We showed that the UV–visible absorption wavelength of squalene in AgNO 3 -methanol solution was obviously red-shifted, and the infra-red vibration wavelength of C C bond slightly decreased, indicating that complexation between squalene and Ag + took place. The distributions of squalene in AgNO 3 methanol solution/petroleum ether under different conditions were further investigated. We found that the fraction of squalene in AgNO 3 -methanol phase was enhanced with increased percentage of methanol and AgNO 3 concentration and decreased extraction temperature. The distribution coefficient of squalene was up to 7.87 under optimum extraction conditions with 70% methanol (v/v), 0.6 mol/L AgNO 3 , reaction time of 12 h, and at the temperature of 0 °C. Furthermore, under the optimum conditions, extraction of squalene from the unsaponifiable portion of camellia oil exhibited high selectivity with a raffinate rate and a back-extraction rate of 73.9% and 72.5%, respectively. The purity of extracted squalene was 37.8%, 108 times more concentrated than that in the starting material. [ABSTRACT FROM AUTHOR]

The variation of the chemical composition concentration and the microhardness values in the surface layer of phosphorus cast iron was investigated after dry sliding. The experimental results indicate that the hardness and chemical composition vary with distance from the sliding surface in the surface layer. The sliding condition and the microstructure of the pin specimen have great effects on the hardness profile and the composition distribution. [Copyright &y& Elsevier]

Abstract: Upon air oxidation, a peptide corresponding to the 30‐residue N‐terminal subdomain of carp granulin‐1 spontaneously formed the disulfide pairing observed in the native protein. Structural characterization using NMR showed the presence of a defined secondary structure within this peptide. The chemical shifts for most of the αCH protons of the peptide and the protein are very similar, and the observed NOE contacts of the peptide strongly resemble those in the protein. A structure calculation of the peptide using NOE distance constraints indicates that the peptide fragment adopts the same conformation as formed within the native protein. The 30‐residue N‐terminal peptide of carp granulin‐1 is the first example of an independently folded stack of two β‐hairpins reinforced by two interhairpin disulfide bonds. Two key areas of the structure show a clustering of hydrophobic residues that may account for its exceptional conformational stability. [ABSTRACT FROM AUTHOR]