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Protein–nucleic acid interactions play essential roles in many biological processes, such as transcription, replication and translation. In protein–nucleic acid interfaces, hotspot residues contribute the majority of binding affinity toward molecular recognition. Hotspot residues are commonly regarded as potential binding sites for compound molecules in drug design projects. The dynamic property is a considerable factor that affects the binding of ligands. Computational approaches have been developed to expedite the prediction of hotspot residues on protein–nucleic acid interfaces. However, existing approaches overlook hotspot dynamics, despite their essential role in protein function. Here, we report a web server named Hotspots In silico Scanning on Nucleic Acid and Protein Interface (HISNAPI) to analyze hotspot residue dynamics by integrating molecular dynamics simulation and one-step free energy perturbation. HISNAPI is capable of not only predicting the hotspot residues in protein–nucleic acid interfaces but also providing insights into their intensity and correlation of dynamic motion. Protein dynamics have been recognized as a vital factor that has an effect on the interaction specificity and affinity of the binding partners. We applied HISNAPI to the case of SARS-CoV-2 RNA-dependent RNA polymerase, a vital target of the antiviral drug for the treatment of coronavirus disease 2019. We identified the hotspot residues and characterized their dynamic behaviors, which might provide insight into the target site for antiviral drug design. The web server is freely available via a user-friendly web interface at http://chemyang.ccnu.edu.cn/ccb/server/HISNAPI/ and http://agroda.gzu.edu.cn:9999/ccb/server/HISNAPI/. [ABSTRACT FROM AUTHOR]

The nanosecond short pulse generator, which operates continuously at MHz repetition rates, plays an important role in high-energy accelerators, pulsed laser modulation, electromagnetic biological effects, and other fields. Pulse-forming lines based on gas spark gap are the main means to generate high-voltage nanosecond short pulses; but due to electrode ablation, it is difficult to operate at MHz repetition rates. The topologies based on the fully controlled semiconductor device can output multimode nanosecond pulse. But it is limited by the gate driver ability and system stray loss, so it is difficult to directly generate flexible and adjustable nanosecond short pulse with MHz repetition rates. In order to overcome the above shortcomings, this article proposes the Blumlein-based LC underdamped oscillation boost circuit and the Blumlein stack topology to achieve high voltage gain. And, the voltage wave process can be adjusted by controlling the switching sequence to change operating mode. Finally, multimode operation such as positive polarity, negative polarity, bipolar and pulse duration modulation can be realized with MHz repetition rates and high gain voltage. [ABSTRACT FROM AUTHOR]

• Individual response to drugs is crucial for personalized medicine. • We developed DREMO for predicting drug response in individuals. • 3 cell line similarity networks and 2 drug similarity networks were constructed. • The similarity information networks were fused with low-dimensional feature vectors. • DREMO addresses the "small n, large p" issue to a certain extent. Predicting the response of each individual patient to a drug is a key issue assailing personalized medicine. Our study predicted drug response based on the fusion of multiomics data with low-dimensional feature vector representation on a multilayer network model. We named this new method DREMO (D rug R esponse pr E diction based on M ulti O mics data fusion). DREMO fuses similarities between cell lines and similarities between drugs, thereby improving the ability to predict the response of cancer cell lines to therapeutic agents. First, a multilayer similarity network related to cell lines and drugs was constructed based on gene expression profiles, somatic mutation, copy number variation (CNV), drug chemical structures, and drug targets. Next, low-dimensional feature vector representation was used to fuse the biological information in the multilayer network. Then, a machine learning model was applied to predict new drug-cell line associations. Finally, our results were validated using the well-established GDSC/CCLE databases, literature, and the functional pathway database. Furthermore, a comparison was made between DREMO and other methods. Results of the comparison showed that DREMO improves predictive capabilities significantly. [ABSTRACT FROM AUTHOR]

The age-stage, two-sex life table was used to determine the effects of the novel ketoponic acid insecticide, spirotetramat, on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) at a concentration of 30mg/L. The results showed that the egg hatch rate was significantly decreased. In addition, the duration of the egg stage was decreased by one day compared to the control cohort. The preadult duration, adult longevity, pre-oviposition period, and total pre-oviposition period of the spirotetramat-treated cohort were all shortened, as were the preadult survival rate, mean fecundity, and net reproductive rate. No significant differences were found in the finite rate of increase and intrinsic rate of increase between the spirotetramat-treated and control cohorts. However, our population projection based on basic data (i.e., survival rate, developmental rate, and fecundity) showed that the population size of F. occidentalis was lower in the spirotetramat-treated cohort than in the control cohort. Our results showed that treatment with spirotetramat (30mg/L) suppressed the population growth of F. occidentalis. Furthermore, by using basic life table data to project population growth, we were able to distinguish differences between the projected growth of the two populations despite not finding a significant difference in their intrinsic rate of increase or finite rate of increase. This novel insecticide can be considered as a suitable candidate for inclusion in pest management programmes. [ABSTRACT FROM AUTHOR]

Sound source visualization has been widely used in many scenarios such as aerospace, industrial production, and urban management. Sound source localization technology plays an essential role in the realization of sound source visualization. The imaging results and calculation cost are the primary considerations in the problem of sound source localization. This article proposes a subspace iteration integrated variational Bayesian (SVB) method to realize adaptive imaging of different sound sources. First, the proposed variational Bayesian (VB) method is based on total variation (TV) prior to balance the sparsity and smoothness of the imaging results. Second, the subspace optimization method in the probability measure space is integrated into the proposed SVB method to solve the involved ill-posed inverse problem. The proposed SVB method can significantly improve the calculation speed, especially for large-scale inverse problems. Finally, the speed and robustness of the proposed SVB method can be demonstrated according to the extensive results of simulation and experimental validation. [ABSTRACT FROM AUTHOR]

Effective drug discovery contributes to the treatment of numerous diseases but is limited by high costs and long cycles. The Quantitative Structure–Activity Relationship (QSAR) method was introduced to evaluate the activity of a large number of compounds virtually, reducing the time and labor costs required for chemical synthesis and experimental determination. Hence, this method increases the efficiency of drug discovery. To meet the needs of researchers to utilize this technology, numerous QSAR-related web servers, such as Web-4D-QSAR and DPubChem, have been developed in recent years. However, none of the servers mentioned above can perform a complete QSAR modeling and supply activity prediction functions. We introduce Cloud 3D-QSAR by integrating the functions of molecular structure generation, alignment, molecular interaction field (MIF) computing and results analysis to provide a one-stop solution. We rigidly validated this server, and the activity prediction correlation was R 2 = 0.934 in 834 test molecules. The sensitivity, specificity and accuracy were 86.9%, 94.5% and 91.5%, respectively, with AUC = 0.981, AUCPR = 0.971. The Cloud 3D-QSAR server may facilitate the development of good QSAR models in drug discovery. Our server is free and now available at http://chemyang.ccnu.edu.cn/ccb/server/cloud3dQSAR/ and http://agroda.gzu.edu.cn:9999/ccb/server/cloud3dQSAR/. [ABSTRACT FROM AUTHOR]

In this study, DDR membranes with a layer thickness of approximately 700 nm were studied for separation feeds comprising mixtures of CO 2 and CH 4. The membranes displayed the highest CO 2 over CH 4 permselectivity and CO 2 permeability reported in literature. This was ascribed to a defect-free and ultra-thin zeolite film as well as an open and highly permeable support. For equimolar mixtures, the highest CO 2 over CH 4 permselectivity of 727 was observed when the pressure at the feed side was 5 bar(a) and the permeate pressure was 1 bar(a) at 25 °C. At these conditions, the CO 2 permeability was very high at 45 × 10−7 mol/(m2 s Pa). Separation experiments for 80/20 and 20/80 mixtures were also performed, and in these cases, CO 2 over CH 4 permselectivities of 1011 and 622 were observed, respectively. For all feeds, the membrane permselectivity decreased slightly at higher temperature and in all cases, higher permselectivity was observed when vacuum was applied at the permeate side. One-stage membrane processes for upgrading biogas to biomethane at three different operating pressures were designed based on the experimental data. In all cases, a quite low membrane area, methane slip and power need were observed. [Display omitted] • DDR membranes with ultrahigh CO 2 permeance for CO 2 /CH 4 separation. • One-stage DDR membrane processes for biogas upgrading. • Low membrane area, CH 4 slip, and power use for these processes. [ABSTRACT FROM AUTHOR]

Thiol-gold (Au) conjugation is perhaps the most routinely applied surface chemistry approach to immobilize receptors within Au-based molecular sensing platforms. However, no previous studies have investigated in situ immobilization in a nanofluidic systems. In this work, flowthrough receptor immobilization is demonstrated, using a nanoslit induced depletion zone to enable direct real-time visualization for characterizing the effect of sodium chloride (NaCl) concentrations during immobilization of thiolated single-stranded DNA on Au. The results show that the amount of fixed-DNA on Au, as well as the non-specific adsorption of DNA on fused silica surface, strongly depend on NaCl levels. Furthermore, the non-specific interaction at high NaCl levels reduces the DNA available for immobilization on Au, but enriches the DNA molecules in the channel under wash by deionized water. By adding Tween-20 to decrease the non-specific adsorption and increasing the driving pressure to increase the DNA flux under high-salt level, the immobilization time can be further decreased to 10 min or less, which is at least an order of magnitude faster than recently proposed bioconjugation methods for thiolated-DNA–Au conjugation. Moreover, this work demonstrates the capability of the platform for DNA- and aptamer-based sensing assays, thereby opening up new strategies for developing biosensors using nanofluidic platforms. [Display omitted] • Real-time visualization of DNA immobilization on Au surface in nanochannels. • The amounts of immobilized DNA on Au surface depend on the NaCl levels. • The adsorption of DNA on the fused silica surface depends on the NaCl levels. • Ultrarapid DNA immobilization on Au surface in the nanochannel (∼ 10 minutes). • Wash-free, real-time visualization for gene and protein detections [ABSTRACT FROM AUTHOR]

We prove that, for every 0 ⩽ s ⩽ 1 , there is a Hamel basis of the vector space of reals over the field of rationals that has Hausdorff dimension s. The logic of our proof is of particular interest. The statement of our theorem is classical; it does not involve the theory of computing. However, our proof makes essential use of algorithmic fractal dimension–a computability-theoretic construct–and the point-to-set principle of J. Lutz and N. Lutz (2018). [ABSTRACT FROM AUTHOR]

A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation. [ABSTRACT FROM AUTHOR]

In Ding's LISH procedure, the lymph nodes alongside the ileocolic artery are dissected, but these are not the regional lymph nodes of transverse colon cancer, according to the definition of the American Joint Committee on Cancer staging manual [[3]]. Laparoscopic surgery, Transverse colon cancer, Lymph node dissection Keywords: Laparoscopic surgery; Transverse colon cancer; Lymph node dissection EN Laparoscopic surgery Transverse colon cancer Lymph node dissection 419 420 2 04/12/23 20230501 NES 230501 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s10151-022-02668-z. [Extracted from the article]

In this paper, a new method of multi-objective optimization of the shape parameters was proposed for the Autonomous Underwater Vehicle (AUV) with both towed and self-propelled, aiming to reduce drag and enhance motion stability during navigation. In this study, the hydrodynamics calculation of AUV was conducted by CFD method covering a wide range of Reynolds number between 105 and 107, and the optimization was performed by NSGA-II multi-objective optimization algorithm. Prior to deploying the optimization process, a sample library was created using the Latin hypercube sampling method to construct the Kriging approximation model. Thereafter, the model was used as the NSGA-II multi-objective optimization function, in which the range of design variables was considered to obtain the Pareto optimal solution. Furthermore, we also introduce and discuss the Pareto optimal points with special characteristics. In addition, the objective function values of these four optimal points were compared with the results of the initial model. The results showed that the drag at the four optimal points were reduced by 12.07%, 11.59%, 10.98% and 7.94%, respectively, and the overturning moments were reduced by 1.96%, 7.38%, 12.73% and 14.08%, respectively. The proposed multi-objective optimization method optimizes the shape of AUV effectively and provides valuable guidance for the design of AUV. • A new method of multi-objective optimization of the shape parameters is proposed for AUV. • Latin hypercube sampling and CFD methods are employed to obtain a surrogate model. • The multi-objective optimization is performed using the NSGA-II genetic algorithm. • The Pareto optimal points with special characteristics are presented and discussed. [ABSTRACT FROM AUTHOR]

In this paper, a new method of multi-objective optimization of the shape parameters was proposed for the Autonomous Underwater Vehicle (AUV) with both towed and self-propelled, aiming to reduce drag and enhance motion stability during navigation. In this study, the hydrodynamics calculation of AUV was conducted by CFD method covering a wide range of Reynolds number between 105 and 107, and the optimization was performed by NSGA-II multi-objective optimization algorithm. Prior to deploying the optimization process, a sample library was created using the Latin hypercube sampling method to construct the Kriging approximation model. Thereafter, the model was used as the NSGA-II multi-objective optimization function, in which the range of design variables was considered to obtain the Pareto optimal solution. Furthermore, we also introduce and discuss the Pareto optimal points with special characteristics. In addition, the objective function values of these four optimal points were compared with the results of the initial model. The results showed that the drag at the four optimal points were reduced by 12.07%, 11.59%, 10.98% and 7.94%, respectively, and the overturning moments were reduced by 1.96%, 7.38%, 12.73% and 14.08%, respectively. The proposed multi-objective optimization method optimizes the shape of AUV effectively and provides valuable guidance for the design of AUV. • A new method of multi-objective optimization of the shape parameters is proposed for AUV. • Latin hypercube sampling and CFD methods are employed to obtain a surrogate model. • The multi-objective optimization is performed using the NSGA-II genetic algorithm. • The Pareto optimal points with special characteristics are presented and discussed. [ABSTRACT FROM AUTHOR]

• The IR-PAC based anti-corrosive coating for rebar was prepared. • Compared with OPC and SAC, IR-PAC had good resistance to Cl- penetration, excellent strength against abrasion and impact ductility. • IR-PAC coated rebars has good corrosion resistance. The anti-corrosive coating has been taken as an effective measure to keep rebars from corrosion. In this study, the iron-rich phosphoaluminate cement (IR-PAC) based anti-corrosive coating for rebar was prepared. The Cl- diffusion coefficient, strength against abrasion, and impact ductility of IR-PAC mortar were tested, with ordinary Portland cement (OPC) and sulphoaluminate cement (SAC) mortar as controls. The experimental results demonstrated that the chloride ion diffusion coefficient of IR-PAC was the lowest at any age. Compared with OPC and SAC, the strength against abrasion of IR-PAC at 90 d increased by 19.19 % and 14.32 %, respectively. The impact ductility of IR-PAC at 28 d increased by 28.21 % and 17.37 %, respectively. IR-PAC had good resistance to Cl- penetration, excellent strength against abrasion and impact ductility, which assisted the coating in blocking Cl- intrusion and resisting damage. The optimum SCMs based coating for rebar is as follows: 10.08 % Fly ash (FA), 0.1 % nano-silica (NS), and 0.65 % superplasticizer (SP). The coatings prepared with this formulation were used for electrochemical experiments. The rebars coated with IR- PAC had good corrosion resistance, which proved it is feasible to use IR-PAC to prepare anti-corrosive coatings for rebars. [ABSTRACT FROM AUTHOR]

• CSFV-specific epitopes, the target of neutralizing antibodies, are identified on the D/A domain of E2 protein. • Epitopes 780–794, 810–824, and 846–850 likely form a complex conformational epitope domain. • The residues 783-MGD-785, 789-FGLCPF-794, 813-AFYLVCPIGWTG-824, and 846-REK-848 are critical for antigenicity. • The residue F789 is critical for the antigenic difference between the Riems strain and other CSFV strains. • The identified epitopes are important for developing improved diagnostic tests for CSF. Classical swine fever virus (CSFV) shares high antigenic homology with other members of the genus Pestivirus. Because several pestivirus species can also infect swine, eliciting cross-reactive antibodies, it is important to define CSFV-specific epitopes for the differential diagnosis of classical swine fever (CSF) by serology. For this purpose, epitope mapping of seven monoclonal antibodies (mAbs), recognizing sites on the D/A domain of glycoprotein E2, was performed using recombinant expressed antigenic domains and mutants of E2, as well as an overlapping peptide library. Three CSFV-specific epitopes, i.e. , 780-IEEMGDDFGFGLCPF-794, 810-NGSAFYLVCPIGWTG-824, and 846-REKPF-850, were identified within the D/A domain of E2. Site-directed mutagenesis further confirmed that residues 783-MGD-785, 789-FGLCPF-794, 813-AFYLVCPIGWTG-824, and 846-REK-848 were critical residues in these regions. In addition, a F789S difference within the epitope 780-IEEMGDDFGFGLCPF-794 was responsible for the absence of binding of two mAbs to the E2 protein of the live attenuated CSFV vaccine strain Riems. Structural modeling revealed that, the three epitopes are located near each other, suggesting that they may form a more complex conformational epitope on the D/A domain in vivo. Six of the mAbs neutralized viruses of diverse genotypes, indicating that the target epitopes are involved in virus interaction with cells. The binding of CSFV to cells was significantly reduced after pre-incubation with either truncated E2 proteins comprising the D/A domain or with the CSFV-specific mAbs targeting the domain D/A. These epitopes identified on the D/A domain are important targets for virus neutralization that might be involved in the early steps of CSFV infection. These findings reveal potential candidates for improving the differential diagnosis of pestiviruses by serology. [ABSTRACT FROM AUTHOR]

Microplastics have significant implications for global ecosystems. The microplastic distribution, types, sources, and quantified microplastic-heavy metal synergistic pollution in agricultural soil in Chengdu, China were analyzed. The microplastics were detected in all soil samples collected from 103 sites, with concentrations ranging from 1333 to 15067 particle kg−1. The abundance of microplastics in grassland (12,667 ± 3394 particle kg−1) was more than twice higher than that in open field, vegetable field, orchard, and woodland. The main morphological types of microplastics included fibers, films, and granules (all "3-Dimensional" microplastics), with the colors red, blue, and transparent. Granular and fiber microplastics were predominantly in particles < 500 mm, while film microplastics were uniformly distributed at all sizes. The plastic compositions were mainly polypropylene and polyethylene plastics, accounting for 20.73% and 27.90% of the soil microplastic, respectively. Agricultural plastic applications and irrigation water were the sources of soil microplastics. The concentration of Cd, Cr, and Cu in the microplastics was strongly correlated with the corresponding concentration in the soils (p < 0.01), and the microplastic-heavy metal synergistic pollution might deteriorate the soil environment. The results of soil TOC measurements were influenced by microplastics in the soil. The results provide important data for the characteristics of microplastics in the agroecosystem. [Display omitted] • Microplastics are widespread in agricultural fields in Chengdu, China. • The highest MPs abundance is in grassland among the five cultivation modes. • The main sources of soil MPs are varied among different cultivation modes. • Cd, Cr, and Cu content in soil and in microplastics are positively correlated. • Microplastics may influence the results of soil TOC measurements. [ABSTRACT FROM AUTHOR]

The seismic permanent displacement is an essential aspect to evaluate the seismic stability of slope. The conventional Newmark block method commonly adopts a constant yield acceleration to determine the seismic permanent displacement of slope. In order to reflect a more realistic behavior of seismic displacement, the dynamic kinetic failure mechanism and the instant displacement model of slope reinforced by prestressed anchors in infinitesimal time are established. The time-dependent formula for dynamic yield acceleration is deduced based on upper bound method. A modified method is proposed to determine the seismic permanent displacement within the framework of Newmark block theory. The results are compared with the existing work with regard to the yield acceleration and seismic permanent displacement. Three typical seismic ground motions are performed to study the responses of the anchor force, the dynamic yield acceleration and the seismic permanent displacement. Results show that the anchor force, the dynamic yield acceleration and the seismic displacement all increase continuously during the excitation of seismic ground motion. The anchor causes the yield acceleration to increase, and the seismic permanent displacement to decrease significantly. The conventional method adopting a constant yield acceleration greatly overestimates the seismic permanent displacement. [ABSTRACT FROM AUTHOR]

This paper shows that nanosecond repetitively pulsed discharges were able to mitigate the response of lean methane-air swirl flames to acoustic excitations, at pressures up to 3 bar. Flame transfer functions with and without plasma discharges were investigated at pressures of 1.2, 2.0, and 3.0 bar, in a frequency range 48–380 Hz. Results show that the plasma discharges decreased by up to 50% the gain of the flame transfer functions, regardless of the pressure. Mechanisms responsible for this effect are discussed. [ABSTRACT FROM AUTHOR]

Fan noise has become an important noise component of civil aviation engines with the increasing bypass ratio. The mode identification method is the key to in-duct fan noise testing. The number of modes that can propagate through the duct increases dramatically for high-frequency in-duct fan noise, which requires a large number of microphones to measure the sound field in the duct. Since the number of modes is usually larger than the number of microphones, it is difficult to realize mode identification. A Sparse Bayesian Learning algorithm for mode identification is proposed to solve this problem in this paper. The in-duct sound field is described by a statistical model, and the inverse problem of mode identification is expressed in a Bayesian framework. The non-convex optimization problem of the cost function is considered, iteratively achieving the sparsest solution via a block coordinate descent algorithm in a majorization-minimization framework. The mode identification method based on Sparse Bayesian Learning has high sparsity and can achieve parameter adaptation. The effectiveness of the Sparse Bayesian Learning method for duct mode identification is verified by numerical simulations and experimental tests. The results show that the mode identification method of Sparse Bayesian Learning can accurately identify the target mode using fewer microphones. • Applying the Sparse Bayesian Learning (SBL) method for mode identification, the strong sparse induction performance of the SBL method is better at suppressing the non-target modes and identifying accurate sparse target modes. • The sparsest mode coefficient amplitudes are solved indirectly by estimating the hyperparameters. The optimal parameters can be determined adaptively by iterations without the need for manual selection of parameters. • It is verified through numerical simulations and experimental tests that the mode identification method of SBL can accurately identify target modes with a small number of microphones, and its results have strong sparsity and robustness. [ABSTRACT FROM AUTHOR]

• The models, imaging algorithms, and applications are systematically compared, analyzed, and concluded in this paper to explore the differences between the PAD-DBF and FDD-DBF techniques and provide guidance on the application of the technology. • A large number of simulations are investigated to explore the imaging characteristics of two rotor aerodynamic dipole source imaging technologies under different testing conditions, including different analysis frequencies, axis directions, SNRs, and measured distances. • The two imaging techniques are applied to the semi-anechoic chamber test for rotating dipole sources and the actual BO105 rotor wind tunnel test, respectively, which is further used to compare and validate the imaging effectiveness and applicability of the two techniques. The acoustic imaging technology for rotating dipole sources has been one of the topics concerned. In recent years, two state-of-the-art imaging technologies for rotating dipole sources were proposed, including beamforming technologies based on the predefined axis direction (PAD-DBF) and frequency-domain deconvolution (FDD-DBF). However, a systematic comparison of these two imaging technologies does not currently exist. In this paper, the models and imaging algorithms are firstly systematically compared and analyzed to explore the differences between the two technologies and provide guidance on the application of the technology. Secondly, extensive simulations are investigated to analyze the performance of the two imaging technologies under different working conditions. Finally, the two imaging technologies are applied to the semi-anechoic chamber test for rotating dipole sources and the actual BO105 rotor wind tunnel test, respectively, which is further used to compare and validate the imaging effectiveness and applicability of the two technologies. The analysis shows that both technologies can effectively achieve rotating dipole source localization. The PAD-DBF technology can achieve a more accurate rotating dipole source location, higher imaging resolution at a lower time cost, and it can get more robust imaging results in the low signal-to-noise ratio (SNR) of the wind tunnel environment. In contrast, the FDD-DBF technology can get a more accurate sound source magnitude while effectively imaging the rotating dipole source. [ABSTRACT FROM AUTHOR]

The acoustic vector sensor (AVS) has a wide application in the direction of arrival (DOA) estimation of sound sources including aircraft, underwater or on-land vehicles, search-and-rescue efforts, etc. The performance of only one acoustic vector sensor can compare favorably with a traditional acoustic array in DOA estimation. The anisotropic noise problem of the vector sensor has had a severe affective on the estimation accuracy and has caused little attention until now. In this paper, an AVS measurement system is designed, and an Anisotropic Sparse Bayesian Learning (SBL) method (the A-SBL method) is proposed to model and estimate the anisotropic noise of the AVS system. A high-resolution DOA estimation method is also introduced based on the noise estimation algorithm. The experimental results exhibit the necessity of modeling the anisotropic noise, and the estimation accuracy of the proposed A-SBL method based on the noise model is verified. The comparison of DOA methods shows the superiority of the proposed method, in which the DOA estimation error is not more than 1 °. The proposed method's utility may be found in applications for localization or tracking of targets with prominent acoustic characteristics when the environment is complicated. [ABSTRACT FROM AUTHOR]

Titanium/steel composite plate was prepared by cold-hot rolling method. The influence of temperature on the interfacial reaction behavior of titanium/steel composite plate was studied by double beam focused ion beam system and spherical aberration correction transmission electron microscopy. The results show that the interfacial reaction of the cold-rolled titanium/steel composite plate mainly occurs in the heating stage, and the continuous intermetallic compounds layer formed at the interface during heating fractures during hot rolling. An interfacial layer composed of submicron TiC layer and α-Ti/α-Fe is formed when the hot rolling temperature is not higher than 850 °C, and the interfacial bonding strength increases with the increase of rolling temperature. An interface layer composed of micro (FeTi+TiC)/Fe 2 Ti layer, nano FeTi/Fe 2 Ti layer and micro pores is formed when the hot rolling temperature exceeds 900 °C. The interfacial micro (FeTi+TiC)/Fe 2 Ti layer and micro pores will seriously damage the interfacial bonding quality. • Titanium/steel composite plate was prepared by cold-hot rolling method for the first time. • An interfacial layer composed of submicron TiC layer and α-Ti/α-Fe is formed when the temperature is lower than 850 °C, and the interface is tightly bonded without pore defects. • An interface layer composed of micro (FeTi+TiC)/Fe 2 Ti layer, nano FeTi/Fe 2 Ti layer and micro pores is formed when the temperature is higher than 900 °C. The interfacial micro (FeTi+TiC)/Fe 2 Ti layer and micro pores will seriously damage the interfacial bonding quality. [ABSTRACT FROM AUTHOR]

Botanicals (BOTs) are well known for their anti-inflammatory and antioxidant activities. They have been widely used as feed additives to reduce inflammation and improve intestinal functions in agricultural animals. However, the effects of BOTs on chicken intestinal epithelial functions are not fully understood. The 3D apical-out chicken enteroids recapitulate the intestinal tissue, and allow convenient access to the luminal surface, thus serving as a suitable model for investigating gut functions. The aim of this study was to identify the roles of BOTs in protecting the intestinal epithelium in chicken enteroids under challenging conditions. Apical-out enteroids were isolated from the small intestines of 18 days-old chicken embryos. Lipopolysaccharide (LPS , 10 µg/mL) and menadione (400 µM) challenges were performed in the media with or without BOTs. Paracellular Fluorescein isothiocyanate–dextran 4kD (FD4) permeability, inflammatory cytokine gene expression, and reactive oxygen species (ROS) generation were analyzed post-BOTs and challenges treatments. Statistical analysis was performed using one-way ANOVA and post hoc multiple comparisons among treatments. The results showed that the LPS challenge for 24 h induced a 50% increase in FD4 permeability compared with nontreated control; thymol, thyme essential oil, and phenol-rich extract significantly (P < 0.02) reduced FD4 permeability by 25%, 41%, and 48% respectively, in comparison with LPS treatment. Moreover, the gene expression of inflammatory cytokines was upregulated, tight junction proteins and defensins were downregulated (P < 0.05) after 6 h of LPS treatment, while these BOTs treatments significantly restored the LPS-induced gene expression alterations (P < 0.05). Menadione oxidative challenge for 1 h significantly increased the ROS level compared with unchallenged control. Enteroids treated with thymol and thyme essential oils showed 30% reduced ROS levels, while the phenol-rich extract reduced them by 60%, in comparison with the challenged group (P < 0.0001). These data confirmed the role of BOTs in supporting the barrier function and reducing the disruptive effects of inflammation and oxidation in the chicken intestine. [ABSTRACT FROM AUTHOR]

Antibody-drug conjugates (ADCs) are a class of tumor cell-targeting drugs that have developed rapidly in recent years. From the perspective of further improving ADC targeting and developing natural macromolecules as drug carriers, it is still challenging and necessary to try new targeted drug delivery modalities. In this study, we have developed an antibody-modified prodrug nanoparticle based on biomacromolecule dextran (DEX) to delivery antitumour drug doxorubicin (DOX). Firstly, oxidized dextran (ODEX) and DOX were bonded to yield ODEX-DOX via Schiff base reaction, which can self-assemble into nanoparticles (NPs) carrying some aldehyde groups. Subsequently, the amino groups of CD147 monoclonal antibody were bound to the aldehyde groups on the surface of ODEX-DOX NPs, resulting in acid-responsive and antibody-modified CD147-ODEX-DOX NPs with relatively small particle size and high DOX loading. FT-IR, UV-Vis, HPLC, and 1H NMR were used to demonstrate the successful synthesis of polymer prodrug ODEX-DOX NPs and antibody-modified nanomedicine CD147-ODEX-DOX NPs. Dynamic light scattering (DLS) was used to evaluate the stability and the pH responsiveness of ODEX-DOX NPs in different media and tumour microenvironment. The in vitro total release content of DOX reached approximately 70% in PB 5.0 buffer solution after 103 h. Furthermore, the in vivo antitumour efficacy and biodistribution experiments confirmed that CD147-ODEX-DOX NPs could significantly inhibit the growth of HepG2 tumour. All of the results indicate that this acid-sensitive nanomedicine has higher safety and targeting effects. It promises to be an ideal strategy for future targeted drug delivery systems and anticancer therapies. [Display omitted] • An antibody-modified nanoprodrug based on oxidized dextran (ODEX) and doxorubicin (DOX) was prepared. • CD147 mAb was bound onto the surface of prodrug ODEX-DOX nanoparticles by Schiff base reaction. • The multifunctional nanoparticles have abilities of active targeting and pH responsive drug delivery. • In vitro and in vivo tests prove that antibody-bonded nanoprodrugs have good targeting and tumor-inhibiting effects. [ABSTRACT FROM AUTHOR]

The ventilation work is an important step to be completed before the start of the positive pressure explosion-proof robot. The existing explosion-proof technology uses constant pressure inflation, which will cause explosive gas to accumulate in the corner area of the cavity for a long time. In order to solve this problem, a ventilation method with periodic pulse intake is proposed. Based on the finite element method, the cleaning and ventilation process of the positive pressure explosion-proof robot is simulated and analyzed. The concentration of explosive gas in the robot cavity with time under constant pressure intake and pulse intake with different periods and amplitudes is compared. The simulation results show that the pulse intake is beneficial to the ventilation of the corner position. The period and amplitude of the pulse intake has an effect on the ventilation efficiency, when the period is the same, the greater the amplitude of the pulse intake, the higher the ventilation efficiency; when the amplitude is the same, the smaller the period of the pulse intake, the higher the ventilation efficiency. After experimental verification, the validity of the simulation results is proved. This study helps to improve the ventilation efficiency of positive-pressure explosion-proof robots and provides guidance for practical applications. [ABSTRACT FROM AUTHOR]

Background: Enormous clinical and biomedical researches have demonstrated that microbes are crucial to human health. Identifying associations between microbes and diseases can not only reveal potential disease mechanisms, but also facilitate early diagnosis and promote precision medicine. Due to the data perturbation and unsatisfactory latent representation, there is a significant room for improvement. Results: In this work, we proposed a novel framework, Multi-scale Variational Graph AutoEncoder embedding Wasserstein distance (MVGAEW) to predict disease-related microbes, which had the ability to resist data perturbation and effectively generate latent representations for both microbes and diseases from the perspective of distribution. First, we calculated multiple similarities and integrated them through similarity network confusion. Subsequently, we obtained node latent representations by improved variational graph autoencoder. Ultimately, XGBoost classifier was employed to predict potential disease-related microbes. We also introduced multi-order node embedding reconstruction to enhance the representation capacity. We also performed ablation studies to evaluate the contribution of each section of our model. Moreover, we conducted experiments on common drugs and case studies, including Alzheimer's disease, Crohn's disease, and colorectal neoplasms, to validate the effectiveness of our framework. Conclusions: Significantly, our model exceeded other currently state-of-the-art methods, exhibiting a great improvement on the HMDAD database. [ABSTRACT FROM AUTHOR]

Recovering ammonia from anaerobic digestion (AD) effluent offers the opportunity to produce a renewable fertilizer and reduce environmental impact. A novel process developed for such an application was evaluated during this study. The feature of the process is integrating biogas stripping and gypsum (CaSO 4 ·2H 2 O) absorption. The result revealed that the lower CO 2 content and the absorption temperature contributed the higher efficiency of ammonia recovery. The gypsum solution recovered around 95% of the stripped ammonia when the stripping gas contained 10% CO 2 and it rose to 100% when the gas contained more than 30% CO 2. Furthermore, a statistical model and genetic algorithm were applied to estimate the total ammonia recovery and optimize the operating parameters. The experimental and modeling results indicated that integrating biogas stripping with gypsum absorption can effectively harvest ammonia nitrogen and reduce CO 2 emissions while producing (NH 4) 2 SO 4 fertilizer from AD effluent. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Total synthesis of (±)-applanatumol B has been achieved in in 8 steps from known compound 8 in 5.0% overall yield. The key step features an acid induced cyclization to construct 5/5/6 tricyclic skeleton. Incorporation of dimethyl malonate into the pentane ring simplifies the synthesis by reducing stereocenters to two. [ABSTRACT FROM AUTHOR]

• A voltage regulation optimization problem is formulated considering source-load-storage collaboration. • An attention-based multi-agent deep reinforcement learning approach is designed for voltage control. • A multi-stage parallel training framework and an evolutionary selection mechanism is adopted to improve the scalability of voltage control. With the increasing penetration of renewable energy in active distribution networks (ADNs), voltage regulation problem is becoming more and more challenging. In this article, we focus on providing a scalable data-driven approach to ensure the voltage security of ADNs with high penetration of PVs. To this end, we first formulate an optimization problem for real-time voltage control considering source-load-storage collaboration while minimizing the total active power curtailment of PVs. Then, we reformulate the above problem as a Markov game and propose a novel voltage regulation algorithm based on evolutionary curriculum-based multi-agent deep reinforcement learning (EC-MADRL) to solve it. The key idea of the proposed algorithm is to adopt a multi-stage parallel training framework based on attention multi-agent deep deterministic policy gradient algorithm (Attention-MADDPG) and use an evolutionary mechanism to select voltage regulation models with high fitnesses in the previous stage, which means that good agents with best adaptability could be utilized for learning in the environment with a larger number of PVs. Simulation results show the effectiveness and scalability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Four new oxepine-containing pyrazinopyrimidine alkaloids, versicoxepines A − D (1 – 4), two quinolinone alkaloid analogs including 3-hydroxy-6-methoxy-4-phenylquinolin-2(1 H)-one (5) and 3-methoxy-6-hydroxy-4-phenylquinolin-2(1 H)-one (6) which were new naturally occurring compounds, together with two known compounds (7 and 8) were isolated from Aspergillus versicolor AS-212, an endozoic fungus isolated from the deep-sea coral Hemicorallium cf. imperiale , which was collected from the Magellan Seamounts in the Western Pacific Ocean. Their structures were determined by extensive analysis of the spectroscopic and X-ray crystallographic data as well as by chiral HPLC analysis, ECD calculation, and DP4+ probability prediction. Structurally, versicoxepines B and C (2 and 3) represent the first example of a new oxepine-containing pyrazinopyrimidine alkaloid whose cyclic dipeptide moiety is composed of the same type of amino acid (Val or Ile). Compound 5 displayed antibacterial activity against aquatic pathogens, Vibrio harveyi and V. alginolyticus , with MICs of 8 μg/mL. [Display omitted] • Four new oxepine-containing diketopiperazines were isolated from deep-sea coral-derived Aspergillus versicolor AS-212. • Chiral HPLC, ECD and DP4+, and X-ray diffraction were used for structure determination. • Compound 5 exhibited potent activities against aquatic- and plant-pathogenic microbes. [ABSTRACT FROM AUTHOR]

• Spatial knowledge was less grasped under pressure than normal conditions. • People with wayfinding experience rely less on signage, but this effect was not significant at landmarks. • The use of signs near the starting point affects the choice of pedestrian routes. This study aimed to examine differences in the development of spatial knowledge under normal and pressure conditions, as well as differences in the use of signage. To this end, a virtual reality environment of a subway station was developed. We conducted a wayfinding experiment in the environment using a headset device with an eye-tracker. The wayfinding performance and eye-tracking data from 48 participants were recorded and analyzed. The results indicated that spatial knowledge was less grasped under pressure than in normal conditions. Despite the particular diversity across wayfinding conditions, we found a higher reliance on signage among first-time participants. Still, this effect was not significant at landmarks. And the importance of signs near the starting point for route selection was also reported. This study is helpful for understanding the differences in wayfinding and signage use across conditions and provides recommendations for signage design and emergency capacity promotion. [ABSTRACT FROM AUTHOR]

In order to realize the lightweight design of mobile pump truck, this paper takes the frame of a certain type of mobile pump truck as the research object. The response surface method is used to carry out lightweight design of the longitudinal beam structure of the frame, and the finite element method is used to establish the finite element model to compare and analyze the optimized and original designs. The results show that the height, width and thickness of the optimized longitudinal beam section are reduced by 10mm, 11mm, and 0.8mm respectively, and the weight of the whole frame is reduced by 35.8kg. Before and after optimization, the displacement and stress changes of the frame are small in four motion situations, which meet the lightweight requirements of optimization design. [ABSTRACT FROM AUTHOR]

Small extracellular vesicles (sEVs) play a key role in exchanging cargoes between cells in tumour microenvironment. This study aimed to elucidate the functions and mechanisms of hepatocellular carcinoma (HCC) derived sEV‐clathrin light chain A (CLTA) in remodelling microvascular niche. CLTA level in the circulating sEVs of HCC patients was analysed by enzyme‐linked immunosorbent assay (ELISA). The functions of sEV‐CLTA in affecting HCC cancerous properties were examined by multiple functional assays. Mass spectrometry was used to identify downstream effectors of sEV‐CLTA in human umbilical vein endothelial cells (HUVECs). Tube formation, sprouting, trans‐endothelial invasion and vascular leakiness assays were performed to determine the functions of sEV‐CLTA and its effector, basigin (BSG) in HUVECs. BSG inhibitor, SP‐8356, was tested in a mouse model of patient‐derived xenografts (PDXs). Circulating sEVs of HCC patients had markedly enhanced CLTA levels than control individuals and were reduced in patients after surgery. HCC derived sEV‐CLTA enhanced HCC cancerous properties, disrupted endothelial integrity and induced angiogenesis. Mechanistically, CLTA remodels microvascular niche by stabilizing and upregulating BSG. Last, SP‐8356 alone or in combination with sorafenib attenuated PDXs growth. The study reveals the role of HCC derived sEV‐CLTA in microvascular niche formation. Inhibition of CLTA and its mediated pathway may illuminate a new therapeutic strategy for HCC patients. [ABSTRACT FROM AUTHOR]

The particle size distribution (PSD), composition, morphology, and formation mechanism of particulate matter (PM) released from the combustion of spent pot lining with and without CaSiO 3 were investigated. The results showed that NaF and Na 3 AlF 6 were found to be the main compositions of PM, and the particle size distribution of PM shows a bimodal distribution. CaSiO 3 substantially inhibited the emission of PM by transforming NaF, Na 3 AlF 6 , and CaF 2 into stable Ca 4 Si 2 O 7 F 2. Moreover, CaSiO 3 also limited the formation of high hazardous PM 0.2 by providing SiO 2 , Al 2 O 3 , and NaAlSiO 4 with high melting points as the core of promoting the growth of PM in particle size. [Display omitted] • Particulate matter emitted from the combustion of spent pot line was measured. • Co-combustion of spent pot line and CaSiO3 inhibited particulate matter emission. • The formation mechanism of particulate matter from spent pot line was clarified. [ABSTRACT FROM AUTHOR]

The measurements of aero-engine fan noise are crucial to engine-noise reduction and silent-turbofan design. The duct mode identification is adpoted to decompose inner duct noises into spinning modes from acoustic pressure measured by a microphone array. However, modes identification of the aero-engine fan are difficult cause the number of modes is usually much larger than the number of microphones and leading to an ill-posed problem during the inverse process. A mode identification method based on Iterative Bayesian Focusing is used to solve this problem. The in-duct sound field is described by a statistical model, and the inverse problem of mode identification is expressed in a Bayesian framework. The sparsity of the target acoustic modes is applied as a priori condition, and a Mode Aperture Function (MAF) is developed. The aperture width of the MAFis automatically updated and contracted through iterations, after which mode coefficients are contracted to a sparsest solution. The used mode identification method is firstly validated through numerical simulations, and the effects of the number of microphones and SNR on mode identification results are discussed. Then the Iterative Bayesian Focusing-based mode identification method is experimentally verified through a well designed Spinning Mode Synthesizer. Both numerical and experimentalresults indicate that target modes can be accurately identified when the number of microphones are much less than the number of all propagating modes. [ABSTRACT FROM AUTHOR]

Reducing the postharvest loss of cereal grains caused by deleterious fungi is critically important for the grain supply chain. Exploring antifungal constituents of plant volatile organic compounds (PVOCs) could promote the development of natural gaseous fungicides in controlling the decay of postharvest grains. In this study, PVOCs were extracted from clove (Syzygium aromaticum L.) buds and the primary constituents thereof were investigated for their effect on Aspergillus flavus growth in media postharvest grains. Fumigation with clove buds' volatiles effectively inhibited A. flavus proliferation in 20% moisture wheat grains under simulated storage conditions. Gas chromatography-mass spectrometry analysis revealed that eugenol and caryophyllene were the two main constituents of clove bud volatiles (49.80% and 36.68%, respectively). An antifungal assay demonstrated that eugenol was responsible for the antifungal activity of clove bud volatiles against A. flavus. Eugenol can completely inhibit A. flavus growth at 0.12 and 0.40 μL/mL in vapor phase fumigation and liquid contact, respectively. The proliferation of A. flavus in 20% moisture wheat grains was completely controlled after fumigation with 600 μL/L eugenol vapor. Eugenol treatment can damage the membrane integrity of A. flavus mycelia, resulting in increased intracellular electrolyte leakage. The 38 metabolites in A. flavus hyphae exposed to 0.40 μL/mL eugenol were markedly differentially expressed and principally involved in the biosynthesis of glycerophospholipids, linoleic acid metabolism, fatty acid metabolism, sugar metabolism, and ATP-binding cassette transporters. Eugenol also causes phosphatidylserine eversion of the plasma membrane, increased reactive oxygen species, decreased ATP production, and damaged DNA in A. flavus. We propose that eugenol treatment can disrupt cell membrane integrity, fatty acid β -oxidation, and induce apoptosis in A. flavus. This study demonstrated the potential application of clove bud volatile organic compounds as biofumigants for postharvest grain management and provided new insights into the antifungal mechanism of the main constituents against A. flavus growth. • Clove volatiles from Syzygium aromaticum , L. could control Aspergillus flavus growth in wheat grains. • Eugenol and caryophyllene are the two main volatile components of clove determined by GC-MS. • Eugenol could inhibit the growth of A. flavus in vapor phase and liquid contact. • The antifungal actions of eugenol on A. flavus were studied by metabolomic and biochemical analyses. • Eugenol could be used as biofumigants for postharvest grain management. [ABSTRACT FROM AUTHOR]

The freshwater resources deficient has been dominated the world's science and policy agenda, owing to the population growth, rapid industrialization, and environmental pollution. Spray evaporator, as a promising and high-efficient desalination technology, has been widely applied to desalination or high salinity wastewater treatment industries. However, current studies on the evaporation characteristics of spray evaporator lack comprehensive analysis and further parameter screening that causes the difficulty to effectively choose optimal parameters for optimization. Therefore, the influences of 11 parameters on evaporation performance were systemically studied via computational fluid dynamics, evaluated via evaporation efficiency, a single droplet evaporation time, and atomization effect, and eventually, the most influential parameters were screened out via stepwise multiple linear regression. The results indicated that all parameters influence the evaporation performance, but the hot air temperature and velocity are the most influential parameters affecting the evaporation efficiency that can jointly explain 55.8 %–58.7 % variations and characteristics of evaporation and should be preferentially considered to improve the efficiency. Furthermore, the compressed air pressure is also worth considering since it could enhance evaporation performance and atomization effect simultaneously. This study provides a new insight and understanding for the design and optimization of spray evaporator. [Display omitted] • The parameter optimization of spray evaporator was comprehensively examined via CFD. • Stepwise multiple linear regression screens out the most influential parameters. • Hot air velocity and temperature are the most key factor for evaporation performance. • Nozzle number and compressed air pressure significantly influence the atomization. [ABSTRACT FROM AUTHOR]

Helicopter detection is an important part of the safety and security during flight. Most of the aerodynamic noise of modern helicopters comes from the main rotor, the main rotor aerodynamic noise thus can be used for helicopter detection. However, the Signal-to-Noise Ratio (SNR) of the measurement noise has always been quite small while the helicopter is flying over long distance away from the microphone. The current passive detection methods are not robust enough in the presence of substantial interference. A robust passive sound detection method is proposed to detect the far-field helicopter based on the cyclostationarity of the main rotor noise. The Sparsity-Enhanced Spectral Coherence (SESC) is derived from the spectral coherence decomposition to improve the detection robustness at far distances and low SNR. Furthermore, a global detector is constructed to detect helicopters adaptively by fusing the detection of multiple orders of BPF, which can be performed on the calculated SESC. More accurate and robust detection of the far-field helicopter can be obtained by the proposed SESC detector. The effectiveness of the proposed detection approach is demonstrated and contrasted by using simulation and far-field flight test measurements of the ROBINSON R22 helicopter. [ABSTRACT FROM AUTHOR]

Bacteria depend on the ferrous iron transport (Feo) system for the uptake of ferrous iron (Fe2+). The Feo system is crucial for colonization and virulence of pathogens. In γ-proteobacteria, the system consists of FeoA, FeoB, and FeoC. The function of FeoA remains unknown. FeoB likely forms the channel, whose regulation has been suggested to involve its GTPase domain (part of its NFeoB domain). FeoC from Klebsiella pneumonia was found to contain a [4Fe 4S] cofactor, whose presence was speculated to enhance the GTPase activity of FeoB (Hsueh, K.-L., et al., J. Bacteriol. 2013 195(20): 4726–34). We present results here that support and extend that hypothesis. We monitored the GTPase activity of FeoB by NMR spectroscopy and found that the presence of 7% FeoC-[4Fe-4S]3+ (the highest level of cofactor achieved in vitro) increased the GTPase rate of NFeoB by 3.6-fold over NFeoB. The effect depends on the oxidation state of the cluster; with reduction of the cluster to [4Fe-4S]2+ the GTPase greatly decreased the GTPase rate. From the effects of point mutations in FeoC on GTPase rates, we conclude that Lys62 and Lys68 on FeoC each contribute to increased GTPase activity on NFeoB. Mutation of Thr37 of NFeoB to Ser nearly abolished the GTPase activity. The GTPase activity of the isolated K. pneumoniae NFeoB-FeoC complex (NFeoBC) was found to be higher in KCl than in NaCl solution. We solved the X-ray structure of the NFeoBC crystallized from KCl and compared it with a prior X-ray structure crystalized from NaCl. We propose a hypothesis, consistent with these results, to explain the factors that influence the GTPase activity. Bacteria may use the oxygen-sensitive cluster as a sensor to up-regulate the gate closing speed. • We demonstrated that when 7% [4Fe-4S]3+-FeoC (holo-FeoC) is bound to FeoB, the GTPase rate could be enhanced by ∼3.6-fold. This is the first Fe-S protein to regulate G protein. • We tried to perturb the [4Fe-4S]3+ cluster with DTT and found that the DTT-reduced cluster ([4Fe-4S]2+) could no longer activate the GTPase. Also, the key local positive charges (K62 and K68) around the cluster of FeoC were found to be essential to the rate enhancement. • We solved a crystal structure in KCl with missing the secondary structures that support the putative activation mechanism. • Also, we purified a threonine to serine (T37S) mutant FeoB protein and found that the GTPase rate of T37S-FeoB dropped by more than 85%. Last, we summarize the structural evidences to explain the putative activation mechanism. [ABSTRACT FROM AUTHOR]

Gamma-proteobacteria is a class of gram-negative opportunistic pathogens existing in the intestinal flora, often leading to diarrhea and intestinal infectious diseases, and plays an important role in maintaining intestinal homeostasis. Type III secretion system (T3SS), an important virulence system, is closely related to the adhesion and invasion and pathogenicity to host cells. Therefore, anti-virulence agents targeting T3SS are important strategies for controlling pathogenic infections. In this study, the anti-Salmonella T3SS active compounds neochebulagic acid (1) , ellagic acid (2) and urolithin M5 (3) were isolated from seed extract of Terminalia citrina by activity-guided isolation method. Based on the fact that urolithins are the main and stable intestinal microbiota metabolites of hydrolysable tannins, we found that the metabolite urolithin B repressed translation and secretion of SipC through the Hha–H-NS–HilD–HilC–RtsA–HilA regulatory pathway. The results provide evidence for Terminalia seeds and ellagitannin-rich berries and nuts in regulating intestinal homeostasis and treating bacterial infection. [Display omitted] • Neochebulagic acid (1), ellagic acid (2) and urolithin M5 (3) are anti-T3SS compounds from Terminalia citrina. • ET-derived intestinal microbiota metabolite urolithin B was identified as a T3SS inhibitor of Salmonella. • Urolithin B represses the T3SS through the Hha–H-NS–HilD–HilC–RtsA–HilA regulatory pathway. [ABSTRACT FROM AUTHOR]

• An online algorithm based on the Bayesian Maximum a Posteriori (MAP) is proposed. • The Gaussian Mixture Model (GMM) is adopted to fit the non-Gaussian noise. • The online Expectation Maximization (EM) algorithm is derived. Harmonic denoising is one of the important preprocessing steps before extracting harmonic signal characteristics. Several signal processing techniques have been developed and applied for denoising the harmonics, which assume that the noise follows a Gaussian distribution and is stationary. However, the noise is often not so simple as a Gaussian distribution, and it could be non-Gaussian and non-stationary in most practical scenarios. A novel online denoising method for the harmonic signal with non-stationary complex noises based on the Bayesian Maximum a Posteriori (MAP) framework is proposed in this paper. The measured signal is divided equally into several frames. Then these frames are transformed into the time-frequency domain by the Short-Time Fourier transform (STFT) and are assumed to be the sum of a low-rank matrix and a noise matrix. The online model of the low-rank matrix and the noise matrix is then constructed between the frames. The online Gaussian mixture model (GMM) and low-rank matrix factorization are performed on the measurement matrix in the complex number domain to reconstruct the harmonic signal. The performance of the proposed method is validated in the simulations. The non-Gaussian and non-stationary noise can be removed more effectively, and the proposed algorithm can improve the frequency estimation accuracy. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process. Design/methodology/approach: The running-in evolutionary was explored in terms of global friction performance. The variation of friction torque and mean COF of the initial 300 engagement cycles was obtained by full-scale tests. Finally, an optical microscope was used to detect the wear characteristics of friction surfaces. Findings: The applied pressure showed a significant influence on the tribological behaviors of wet clutches during the running-in process. The mean COF decreased and then increases with the increase of the applied pressure. A higher applied pressure contributed to more asperity summits being sheared, thus resulting in a smoother surface. Considering a suitable wore performance, properly applied pressure is necessary. Originality/value: The results provide theoretical guidance for selecting the optimal applied pressure in the running-in of wet clutches. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0256/ [ABSTRACT FROM AUTHOR]

Aerobic glycolysis is critical for the energy metabolism of cancer cells. This study focuses on the regulation of forkhead box A2 (FOXA2) on pyruvate kinase M2 (PKM2) and their effects on the glycolytic activity and malignant phenotype of thyroid carcinoma (THCA) cells. By analysing four Gene Expression Omnibus datasets and querying bioinformatics systems, we obtained FOXA2 as a poorly expressed transcription factor in THCA. Later, we validated decreased mRNA and protein levels of FOXA2 in THCA cells by quantitative polymerase chain reaction and western blot assays. FOXA2 upregulation in THCA cells suppressed the glucose uptake and lactate production, and it reduced the extracellular acidification rate, but increased the oxygen consumption rate of cells. Meanwhile, the FOXA2 overexpression blocked the proliferation and mobility, and the tumourigenic activity of cancer cells. The chromatin immunoprecipitation and luciferase assays showed that FOXA2 bound to PKM2 promoter and suppressed the transcription of PKM2, which was highly expressed in THCA cells. Further upregulation of PKM2 elevated the β‐catenin, c‐Myc and cyclin D1 levels and restored the glycolytic activity as well as the malignant properties of cancer cells. Collectively, this work reveals that FOXA2 suppresses aerobic glycolysis and progression of THCA by blocking PKM2 transcription and inactivating the Wnt/β‐catenin pathway. [ABSTRACT FROM AUTHOR]

This paper attempts to study the irreducibility on complete prefix code (CPC-irreducibility) of a Markov shift over a free group, a topological mixing property first considered for shift spaces over free semigroups that induces chaotic behavior such as the existence of a dense set of periodic points. An example shows that the (d , c) -reduction, an effective algorithm of determination of CPC-irreducibility of Markov shifts over free semigroups (Ban et al. in J Stat Phys 177:1043–1062, 2019), fails for general Markov shifts over free groups. This paper reveals an algorithm for determining the CPC-irreducibility of Markov shifts over both free semigroups and groups. Furthermore, such an examination is finitely checkable, and an upper bound for the complexity of the algorithm is provided. [ABSTRACT FROM AUTHOR]

To implement various artificial intelligence and automation applications in smart factories, edge computing and industrial Internet of Things (IIoT) devices must be widely deployed, so as to increase the demand of coping with huge-scale and high-diversity data. Through deployment of fifth-generation (5G) networks (providing wide broadband, low latency, and massive machine type communications), industrial wireless networks, cloud, and fixed/mobile end devices in smart factories are interoperated in a harmony. However, with the huge-scale deployment of 5G networks and the IIoT in smart factories, threats and attacks against various vulnerabilities increase enormously, and cause considerable security and privacy challenges. Consequently, this article investigates crucial security and privacy issues for 5G-IIoT smart factories in three entities (i.e., physical layer, data layer and application layer), and further surveys recent approaches based on deep learning, reinforcement learning, and blockchain. In addition, this article provides future perspectives and challenges along this line of research. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zeolite membrane processes were designed for biogas upgrading. • The processes were compared with polymeric membranes processes. • Zeolite membrane displayed 1000 times higher permeance and much higher selectivity. • Two and three membrane stages were needed for zeolite and polymeric membranes, respectively. • Zeolite membrane processes need significantly less electricity and are less costly. Zeolite membrane processes were designed for biogas upgrading for feed pressures ranging from 5 to 20 bar and compared with corresponding polymeric membrane processes. The mass transfer through zeolite membranes was estimated by a model accounting for adsorption and diffusion through the surface barriers and the interior of the pores, while the mass transfer through polymeric membranes was estimated using reported permeances for commercial polymeric membranes. The zeolite membranes displayed approximately three orders of magnitude higher permeance and up to 7 times higher selectivity. To reach a low methane loss, two and three membrane stages were needed for zeolite and polymeric membranes, respectively, because of the differences in selectivity. Due to the higher selectivity, the electricity need for the zeolite membrane process was only 50–60% of that for the corresponding polymeric membrane process. As a result of the much higher permeability, the zeolite membrane processes were much more compact than the equivalent polymeric membrane processes. The estimated cost for zeolite membranes prepared in small scale including modules was much lower than the cost for industrially produced polymeric membranes including modules. [ABSTRACT FROM AUTHOR]

• The propagation process of a randomly inhomogeneous medium is considered rather than based on the free field assumption. • The numerical solution of Green's function is used instead of the original analytical solution of Green's function. • The IBF algorithm based on the Bayesian framework is used to achieve acoustic imaging in the inhomogeneous propagation media. A random inhomogeneous sound propagation medium is considered in acoustic imaging, which is modeled by a random function of the spatial medium. The inhomogeneity of the sound propagation environment can cause large errors in the modeling and measurement of acoustic imaging. Since the wave equation contains random variables, Green's function no longer has a specific analytical solution. The main work of this paper is as follows: (1) The acoustic inverse problem is considered in the inhomogeneous sound field, which is expressed according to predefined statistical information; (2) Karhunen-Loève expansion is used to simplify the proposed inhomogeneous propagation sound field, and the numerical solution of Green's function is used instead of the original analytical solution; (3) A dual-driven (including data-driven and knowledge-driven) algorithm based on the Bayesian framework is developed to achieve acoustic imaging, which is implemented through the joint estimation of the aperture function and the sparse prior. Finally, the proposed model and algorithm are verified by a numerical simulation. The proposed algorithm is compared with conventional beamforming in terms of localization accuracy and sound power quantization. The simulation results show that the inhomogeneous sound field can be represented by a small number of random variables, and the proposed dual-drive algorithm can accurately achieve acoustic imaging in the inhomogeneous propagation environment. [ABSTRACT FROM AUTHOR]

A novel strategy to modify the dense framework from different types of amine-functionalized organosilica membranes has been successfully applied via nickel-coordination to induce the formation of microporous membranes. Prior to the nickel-coordination reaction, aminosilica sols were prepared via hydrolysis of several types of amine precursors: bis [3-(trimethoxysilyl) propyl] amine (BTPA), trimethoxy [3-(methyl amino) propyl] silane (MAPTS), and 3-aminopropyl triethoxy silane (APTES). The optimal nickel/amine mole ratio was established within a range from 0 to 0.50 mol mol−1, and calcinations of the membranes were performed at 250, 300, and 350 °C. We found that nickel doping restructured the aminosilica network via a coordination bond, which then increased both the rigidity of the organic chain and the surface area of the resultant materials on the order of nickel-doped bis [3-(trimethoxysilyl) propyl] amine (Ni-BTPA) > nickel-doped 3-aminopropyl triethoxy silane (Ni-APTES) > nickel-doped trimethoxy [3-(methyl amino) propyl] silane (Ni-MAPTS). Spectroscopy characterization studies such as Ultraviolet–visible (UV–vis), Fourier Transform Infrared (FT-IR), and X-ray Diffraction (XRD) along with micropore analysis of N 2 sorption isotherms revealed that the formation of a coordinated network could be sterically hindered by the existence of non-hydrolyzable methyl groups on the pendant chain. The prepared composite membranes were utilized for the pervaporation of various types of organic mixtures for a composition ratio of methanol/solvents of 10/90 wt% at 50 °C. All nickel-composite membranes showed high flux and outstanding performance for the pervaporation of methanol/dimethyl carbonate (MeOH/DMC) and methanol/toluene (MeOH/Tol) mixtures. Ni-BTPA membranes with bridge-structured secondary-amine ligands recorded values for the flux that reached as high as 1.42 kg m−2 h−1 with an optimum separation factor for MeOH/Tol of 5,000. [Display omitted] • Hybrid nickel-doped aminosilica membranes were modified via bridge and pendant structure. • Nickel doping restructured the aminosilica network, resulting in higher rigidity and porosity. • The effect of nickel/amine mole ratio and calcination temperature were studied. • New formed subnanopores and the excess of nickel facilitated the diffusion of methanol. • Bridge-aminosilica structure gives the best pervaporation performance. [ABSTRACT FROM AUTHOR]