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Isobavachalcone (IBC) is one of the flavonoid components in Fructus Psoraleae, and has been found multiple pharmacological effects. However, the hepatotoxicity of IBC has been overlooked and not been carefully studied. We aim to find out the cytotoxicity of IBC on HepG2 cells, and explore the underlying mechanisms. HepG2 cells were treated with IBC for 24 h, then MTT assay and LDH assay were used to detect the cell viability. The apoptosis and reactive oxygen species (ROS) production were reflected by the flow cytometry. Using Seahorse Analyzer, we measured the mitochondrial respiratory capacity. The expression of oxidative stress and mitochondrial apoptosis-related proteins were determined by Western blot. The results showed that IBC induced the cell death and apoptosis of HepG2 cells. IBC initiated the accumulation of ROS in cells and impaired the mitochondrial function, triggered apoptosis and suppressed the phosphorylation of Akt. Additionally, scavenging ROS by the antioxidant N-acetyl-l-cysteine (NAC) reduced IBC-induced mitochondria damage and increased Akt phosphorylation. Taken together, IBC caused mitochondrial damage and induced hepatotoxicity by ROS accumulation and Akt suppression. Targeting oxidative stress and depressing mitochondrial damage may provide a theoretical basis for the treatment and prevention of IBC-induced hepatotoxicity in clinic.

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare monogenetic disease, which is characterized by susceptibility to some weakly virulent mycobacteria. Here, we explored the pathogenic genes and molecular mechanisms of MSMD patients. We recruited three patients diagnosed with MSMD from two families. Two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene were identified from two families. The translocation of K410E mutant STAT1 protein into nucleus was not affected. The binding ability between gamma-activating sequence (GAS) and K410E mutant STAT1 protein was significantly reduced, which will reduce the interaction between STAT1 protein with the promoters of target genes. The M691V mutant STAT1 protein cannot translocate into the nucleus after IFN-γ stimulation, which will affect the STAT1 protein form gamma-activating factors (GAF) and bind the GAS in the promoter region of downstream target genes. Taken together, our results showed that the mutation of K410E led to impaired binding of STAT1 to target DNA, and the mutation of M691V prevented the transport of STAT1 into the nucleus, which led to MSMD. Together, we identified two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene in MSMD patients, and deciphered the molecular mechanism of MSMD caused by STAT1 mutations.

In the fluid catalytic cracking (FCC) unit, cyclones possess very less efficiency in the separation of particles smaller than 5 μm. Heterogeneous condensation, one of the most promising preconditioning technologies, can be applied in the FCC unit to improve the particle removal efficiency of cyclones. In this paper, the lab-scale equipment on heterogenous condensation was established and tested. Based on experimental investigation, a novel numerical method was presented to simulate the process of movement and growth of particles in the growth tube. The effects of critical operational parameters, such as the wall film temperature, gas inlet temperature, gas flow rate, and particle number concentration, were studied. The results show that when the gas flow rate is 2 lit·min−1, the average particle size at the outlet increased to 6.67 μm, and the number of particles smaller than 4 μm decreased to about 5%. Overall, this study guides for practical engineering applications.

In this review paper, the most recent research on intracerebral hemorrhage (ICH) is summarized and novel perspectives are offered on the pathomechanisms of ICH. These underlying pathomechanisms of ICH provide clues for development of novel drugs or drug target screening. Specifically, recent research has provided evidence that iron chelators, lipid peroxidation/ferroptosis inhibitors, agonists or antagonists of prostaglandin E2 receptors (EP1/3 or EP2), and nonsteroidal anti-inflammatory drugs protect against ICH-induced brain edema, secondary brain tissue damage as well as inhibition of the toxicity in related tissue damage products. This review will provide a theoretical basis for testing new compounds that may have potential for future clinical trials.

In this review, we compare behavioral protocols (e.g., equipment specification, test duration), evaluation indexes, application characteristics, and advantages and disadvantages of six tests used to assess post-stroke depression and anxiety in rodent models. We also discuss experimental models of intracerebral hemorrhage, the neuroanatomic and pathophysiologic basis of behavioral tests, their applications in drug screening, and their limitations. This review will facilitate the performance of behavioral tests in basic research and ultimately provide references for the clinical diagnosis and treatment of post-stroke depression.

In order to improve the uniformity of solid distribution in the industrial riser, the combination of a novel pre-lifting structure and wedged-shaped baffles were proposed. The performance of three types of risers were compared under different solid circulation rate and gas velocity. The effects of baffles locations and baffles thickness were explored. The results show that the standard deviation of the solid volume fraction (SDSVF) in the novel riser with baffles decreases by >50% in comparison with that in the traditional riser. The increase of distance between baffles and the decrease of baffles thickness may lead to the deterioration of gas-solid contact. In addition, when the scale of the novel riser with baffles is enlarged to 2.5 times at solid circulation rate of 450 kg/(m2·s) and gas velocity of 10 m/s, the standard deviation of solid volume fraction increases by 73.91%, which provides the guidance for practical engineering applications.

A quasi-consistent integration method is presented for the efficient meshfree analysis of Helmholtz problems. The plane wave basis functions are employed for the reproducing kernel meshfree approximation to accurately represent the acoustic field resulting from Helmholtz problems. In order to improve the computational efficiency of Galerkin meshfree analysis of Helmholtz problems, a reproducing kernel gradient smoothing approach is introduced into the meshfree formulation with plane wave basis functions. In the proposed method, the smoothed gradients of meshfree shape functions with plane wave basis functions are built upon a reproducing kernel gradient representation and the integration consistency of Galerkin meshfree formulation is implicitly ensured. Furthermore, a quasi-consistent integration scheme is proposed to compute the smoothed gradients, which aims to balance the efficiency and accuracy for meshfree analysis of Helmholtz problems. The proposed integration method leads to fully consistent integration when one wave direction is considered, and nearly consistent integration if two wave directions are taken into account, where the boundary sample points of integration cells are particularly preferred since they are simultaneously used by neighboring integration cells with efficiency gain. Numerical results demonstrate that the proposed methodology is much more efficient and accurate for Galerkin meshfree analysis of Helmholtz problems, in comparison with the standard meshfree formulations using high order Gauss quadrature rules.

The effective removal of particulate matters from the flue gas emitted from Urea Prilling Tower is very essential to conform to the environmental standards. Based on particle capture theory, the user-defined-function (UDF) codes were written to implement the simulation of particle removal. A novel numerical simulation method is carried out to study the flow field and the effects of gas-phase loading factor, spray density, particle size and droplet size on the particles removal efficiency. The results show that the removal efficiency of particles above 10 μm can reach 97%. But the removal efficiency of particles less than 10 μm deteriorates with decreasing particle diameter due to the randomness of a fine particle movement. In addition, the improved empirical correlations of the removal efficiency were obtained based on numerical simulation, which provides the guidance for optimum design of a spray scrubber in practical engineering applications.

Preheating coal water slurry (CWS) before entering the gasifier can improve gasification efficiency and reduce oxygen consumption. Shell-and-tube heat exchangers (STHXs) with ladder-type fold baffles were applied to preheating of CWS. And experiments were performed when CWS was in shell side and conductive oil flowed in tube side. The different concentration (52.13 wt%, 55.56 wt% and 57.67 wt%) of CWS fitted Bingham model had a significant effect on thermal-hydraulic performance. The experimental results show that, both shell-side temperature difference and overall heat transfer coefficient are the highest when the concentration of CWS is 52.13 wt%, and the shell-side pressure drop is the lowest. The temperature difference per unit pressure drop of CWS with 52.13 wt% and 55.56 wt% increases by 119.3%–290.2% and 55.2%–96.9% compared with that of CWS with 57.67 wt%, respectively, and overall heat transfer coefficient per unit pressure drop also decreases with the increasing of concentration of CWS. Based on experimental data, empirical correlations of Nu and f are obtained and the adjusted coefficient of determination (Adj.R2) is between 0.980 and 0.997. And compared with STHXs with fold baffles, selecting STHXs with ladder-type fold baffles is priority to preheat CWS.

Cryogenic correlative light and electron microscopy (cryo-CLEM) seeks to leverage orthogonal information present in two powerful imaging modalities. While recent advances in cryogenic electron microscopy (cryo-EM) allow for the visualization and identification of structures within cells at the nanometer scale, information regarding the cellular environment, such as pH, membrane potential, ionic strength, etc., which influences the observed structures remains absent. Fluorescence microscopy can potentially be used to reveal this information when specific labels, known as fluorescent biosensors, are used, but there has been minimal use of such biosensors in cryo-CLEM to date. Here we demonstrate the applicability of one such biosensor, the fluorescent protein roGFP2, for cryo-CLEM experiments. At room temperature, the ratio of roGFP2 emission brightness when excited at 425 nm or 488 nm is known to report on the local redox potential. When samples containing roGFP2 are rapidly cooled to 77 K in a manner compatible with cryo-EM, the ratio of excitation peaks remains a faithful indicator of the redox potential at the time of freezing. Using purified protein in different oxidizing/reducing environments, we generate a calibration curve which can be used to analyze in situ measurements. As a proof-of-principle demonstration, we investigate the oxidation/reduction state within vitrified Caulobacter crescentus cells. The polar organizing protein Z (PopZ) localizes to the polar regions of C. crescentus where it is known to form a distinct microdomain. By expressing an inducible roGFP2-PopZ fusion we visualize individual microdomains in the context of their redox environment.

Vanadium Dioxide (VO2) has gained wide attention for various applications as it undergoes a crystallographic transition from the monoclinic phase to the tetragonal phase at 68 °C, accompanied by huge transmittance contrast in the near-infrared (NIR) range and negligible change in the visible range. In this paper, we present a unique Layer-by-Layer self-assembled approach to construct a VO2/spacing superstructure with controlled VO2 layers, spacing thicknesses, and repeating times. The simulation indicates that such structures give intriguingly temperature-dependent light interference phenomena, which was demonstrated its potential applications in smart windows and the calculated results suggest this approach outperforms existing approaches. This simple and versatile solution-based approach opens a new avenue to fabricate the controlled optical stack which could be explored in other applications. Ministry of Education (MOE) National Research Foundation (NRF) The Principal Investigator of this project (Y.L.) wishes to thank Sino-Singapore International Joint Research Institute for funding support. This research is supported by the Singapore Ministry of Education (MOE) Academic Research Fund Tier One RG200/17, RG103/19 and the National Research Foundation, Prime Minister’s Office, Singapore under its Campus for Research Excellence and Technological Enterprise (CREATE) programme.

A superconvergent meshfree collocation method with smoothed nodal gradients is presented. In this method, the first order smoothed gradients of meshfree shape function are constructed through a meshfree interpolation of the standard derivatives of meshfree shape function, while the second order smoothed gradients are computed through directly differentiating the first order smoothed gradients. It is noted that the second order smoothed gradients evaluated at meshfree nodes can be conveniently expressed as two successive first order gradient smoothing operations on the meshfree shape function, which facilitates a trivial numerical implementation. Subsequently, an employment of the second order smoothed gradients in the strong form of a given problem leads to the gradient smoothing meshfree collocation method purely using nodes as the collocation points. Based upon a local truncation error analysis, it is systematically shown that the proposed meshfree collocation method yields superconvergent solutions for odd degree basis functions. A key ingredient attributed to this superconvergence property is that the second order smoothed gradients meet the consistency conditions which go one order beyond the original basis degree of meshfree approximation. Another interesting fact is that the present formulation enables a convergent collocation scheme when the linear basis function is used in meshfree approximation, which is non-feasible in the conventional collocation formulation. The effectiveness of the proposed methodology is validated by numerical examples for both potential and elasticity problems. Numerical results well demonstrate the superconvergence and higher efficiency of the present gradient smoothing meshfree collocation method.

A novel approach named laser induced molten transfer (LIMT) was proposed to rapidly fabricate the metallic patterns on the insulating substrates with high bonding strength by nanosecond laser direct writing. The laser beam selectively irradiated and melted the donor foil and transferred the molten droplets on the target substrate by the induced laser shock, resulting in the formation of designed metallic pattern. The processing parameters were firstly optimized, the morphology of transferred pattern was characterized, and the pattern conductivity and bonding strength were investigated experimentally. The optimized processing parameters for the fabrication of high-quality pattern were the scanning speed of 750 mm/s, laser power of 21 W, and scanning interval of 15 μm. This transferred copper pattern was porous and composed of aggregated micro droplets. The copper pattern surface was homogeneously rough and its edges were clear. The electrical resistivity of transferred pattern was approximately 8 times of the bulk copper due to the oxidation of copper droplets and porosity of pattern. The transferred copper pattern has good bonding strength on the glass substrate due to the existence of a copper-glass recast layer. A micro-heater pattern was integrated in a microfluidic chip, which demonstrated the LIMT approach can selectively transfer pattern on 3D surface. LIMF can successfully transfer the pure metal and alloy patterns on the various target substrates, even the flexible substrate, which further exhibited its excellent versatility and flexibility.

A kind of shell-and-tube heat exchangers with fold baffles was proposed to eliminate the triangular leakage zones between adjacent baffles. An effective algorithm combing second-order polynomial response surface method and multi-objective genetic algorithm was adopted to study the effect of fold baffle configuration parameters on the performance of flow and heat transfer. The helical angle, overlapped degree and shell-side inlet velocity were chosen as design parameters, and the Nusselt number and shell-side pressure drop were considered as objective functions. The results show that both the Nusselt number and shell-side pressure drop increase with the decrease of helical angle and shell-side inlet velocity, and increase with the increasing overlapped degree. A set of Pareto-optimal points were obtained, and the optimization results illustrate a good agreement with CFD simulation data with the relative deviation less than ±3%. And the empirical correlations of Nusselt number and friction coefficient were obtained based on response surface method, the helical angle and overlapped degree were fitted into empirical correlations as correction factors for the first time. It is found that the adjusted coefficient of determination of the Nusselt number and friction coefficient is 0.943 and 0.999, respectively, which illustrate the fitting is correct and reliable.

The effects of geometrical parameters on thermal resistance based on entransy dissipation caused by heat transfer ( R ht ) and fluid friction ( R ff ) of spiral-wound heat exchanger (SWHE) were studied by numerical method. The simulation results show that all geometrical parameters (spiral angle, external diameter, layer pitch, tube pitch) are negatively correlated with R ff because of flow pattern transition caused by the variation of geometrical parameters and the changing of effective flow area which would cause the decrease of entransy dissipation related to fluid friction. For the entransy dissipation due to the heat transfer, the increase of layer pitch are positive to it while both the tube pitch and external tube diameter are negative to R ht , and with the increase of the spiral angle, the R ht decrease at first and then increase. What is more, the MOGA optimization of SWHE was carried out based on different types of objective functions. Compared with the traditional objective functions (minimize Δ P and maximize K ), R ff and R ht obtained from minimizing the entransy-dissipation-based thermal resistance reduce by an average of 90.51% and 34.13%, respectively. Compared with original structure, the comprehensive performance evaluation factor ( Nu/f 1/3 ) of traditional optimal results is improved by an average of 41.02%, while that of optimal structures obtained from entransy theory is strengthened by an average of 76.64%. The results demonstrate that the objective functions of minimizing the entransy-dissipation-based thermal resistance are better than that of traditional objective functions for optimization of spiral wound heat exchanger.

Surface photovoltage spectroscopy (SPS) was applied to the analysis of particulate La 5 Ti 2 CuS 5 O 7 and SrNbO 2 N photoelectrodes fabricated by a particle transfer method, as a means of assessing charge separation under illumination. The critical roles of the back contact metals and cocatalyst in generating charge separation and defining various photoelectrochemical properties were confirmed. The results suggests that SPS in conjunction with particle transfer technology potentially allows the identification of the most beneficial photoelectrode components for photoelectrochemical water splitting.

The configuration parameters of helical angle and overlapped degree of shell-and-tube heat exchangers with helical baffles have been discussed for the thermal-structural comprehensive performance. Based on fluid-structure interaction theory, a method on configuration optimization of shell-and-tube heat exchangers with helical baffles is introduced using second-order polynomial regression response surface combined with Multi-objective Genetic Algorithm. The results show that the heat transfer coefficient per unit pressure drop of shell-and-tube heat exchangers with helical baffles increases firstly and then decreases with the increase of helical angle, and decreases with the increase of overlapped degree under certain shell-inlet velocity. And the performance of flow and heat transfer is more sensitive to helical angle compared with overlapped degree. The maximum shear stress increases with helical angle, but it is almost unaffected by overlapped degree for mechanical properties of helical baffles. The objectives of optimization are the heat transfer coefficient per unit pressure drop maximizing and maximum shear stress minimizing with scope of allowable stress, and three optimal structures are obtained. The optimal results indicate that the heat transfer coefficient per unit pressure drop increases averagely by 14.1%, the maximum shear stress decreases averagely by 4.1%, which provides theoretical guidance for industrial design of shell-and-tube heat exchangers with helical baffles.

A process combined laser-induced plasma-assisted ablation (LIPAA) with chemical corrosion is proposed to fabricate micro-channels with micro-texture surface on glass. Micro-cracks form under the recast layer of glass due to the thermal expansion and contraction strain induced by the plasma during LIPAA. This “defect”, micro-cracks, can be further developed into tree-like micro-textures as the recast layer is removed by chemical corrosion. The effects of chemical corrosion, including corrosive time and corrosive concentration, on the micromorphology of surface texture were investigated. Several representative textures on channel surface were obtained. In order to fabricate micro-channels with micro-texture surface, the effecting factors of LIPAA, including number of scanning cycles, scanning speed, pulse power density and gap distance between glass and sacrificial material, on the channel geometry and chemical corrosive rate were also investigated. The results show that the gap distance is the most significant influence factor on the channel width before chemical corrosion. The corrosive rate of channel width increases with power density and decreases with gap distance. The channel depth before corrosion and its corrosive rate increase with power density and decrease with scanning speed and gap distance. The corrosive rate of width and depth increases with number of scanning cycles till 150, and then reaches steady. The micro-channel with micro-texture surface fabricated by LIPAA and chemical corrosion can be potentially applied in some microfluidic devices.

Improving the removal efficiency of gas cyclones becomes critical as air pollution aggravates. This study aims to investigate the effects of operating parameters on the process of heterogeneous condensation and separation performance of gas cyclones. For hydrophilic fine particles, an experimental apparatus was built up to analyze the heat transfer and removal efficiency. Then a two- way coupling numerical model in which the interactions between particles and gas was achieved by user defined function was adopted. Compared with experimental and numerical results, the accuracy of simulation satisfied engineering application. In addition, as the initial supersaturation degree S0 increases, the particle size at growth chamber outlet and removal efficiency increase by 69.89%, 107.01% respectively. While increasing the gas flow rate F decreases particle size by 3.59% and increases removal efficiency by 17.91%. By heterogeneous condensation preconditioning technique, the removal efficiency for fine particles can reach 95.12%. These results can help optimize and apply this preconditioning technique of gas cyclones in engineering.