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Summary: Okara, a natural source of dietary fibre (DF), is recognised as an edible and safe material. In this study, lactic acid bacteria (LAB) and Kluyveromyces marxianus were used to ferment okara in separately or in combination, and the physicochemical and functional characteristics of obtained insoluble dietary fibre (IDF) excluded from okara were compared. The result showed that compared with non‐fermented okara, the content of IDF from co‐fermented okara by LAB and K. marxianus increased by 6.8%, while separate fermentations were 2.4% and 4.0%. Scanning electron microscopy result showed that the structure of co‐fermented okara IDF was looser and porous with the edge disappeared compared to separate and non‐fermented okara. All the fermentation treatment groups effectively reduced the particle size and affected the cellulose and hemicellulose functional groups of IDF. Furthermore, compared with non‐fermented okara, processing performance, and the activities of hypoglycaemic and hypolipidaemic of IDF were greatly improved in fermented okara. [ABSTRACT FROM AUTHOR]

Objective: Neurogenic bladder (NGB) is a serious complication after spinal cord injury (SCI), a destructive neurological disease. This study focused on exploring the efficacy of the magnetic stimulation of sacral nerve roots combined with Tui-na in treating NGB after SCI. Methods: One hundred patients with NGB after SCI were studied, and intermittent clean catheterization was performed with a water intake program, and patients were grouped into four groups by the random number table method: general treatment group, Tui-na group, magnetic stimulation group, and combined treatment group. A series of relevant factors (voiding diary, urodynamics, and quality of life scores) and clinical efficacy of patients in the four groups before and after treatment were observed. Results: The magnetic stimulation of sacral nerve roots alone, Tui-na alone, and the combination of both were all effective in improving bladder function and quality of life in patients with NGB after SCI, including improvements in voiding frequency, single urine output, maximum urine output, residual urine output, bladder volume and quality of life scores in patients with NGB after SCI. The efficacy of the magnetic stimulation of sacral nerve roots combined with Tui-na was better than that of the magnetic stimulation of sacral nerve roots alone and the Tui-na alone. Conclusion: This research demonstrates that the magnetic stimulation of sacral nerve roots combined with Tui-na treatment could effectively improve the urinary system and the quality of life of patients with NGB after SCI, which is worthy of clinical promotion and application. [ABSTRACT FROM AUTHOR]

Seawater temperature and salinity are basic marine environmental parameters, which can be used to calculate other marine environmental parameters. However, most of the on-site observation data have the problems of uneven spatial distribution and time discontinuity, and it is difficult for remote sensing observation methods to obtain subsurface information. In this study, we proposed a deep learning model with combining remote sensing temperature and salinity as well as in-situ measured data by Argo profiles, and the nonlinear relationship was revealed. An effective and direct inversion method was realized for underwater three-dimensional thermohaline structure based on remote sensing temperature and salinity at accurate points on global scale. The SST data were obtained from the FY3C-VIRR daily sea surface temperature product, the SSS data were acquired from the SMAP Level 3 8-day running averages sea surface salinity product, and the Argo scatter data were got from the ‘Global Ocean Argo Scatter Data Set’. Based on the temporal and spatial location information of the data, this paper matched the remote sensing data from 2016 to 2019 with the Argo data, 64751 valid pairing points were obtained. The deep learning model was constructed as a multilayer perceptron model with 5 hidden layers. The RMSE of temperature had a maximum value of 2.106°C in 130 m depth and a minimum value of 0.367°C in 1000 m with an average of 1.174°C for validation dataset. And the RMSE of salinity had a maximum value of 0.356 psu in 0 m and a minimum value of 0.045 psu in 1000 m with an average of 0.202 psu. Compared with other methods based on fixed mesh products, this study realized a direct inversion method at any location in the global ocean and improved the inversion accuracy, which provides a reliable data support for refined marine monitoring. [ABSTRACT FROM AUTHOR]

Exploring high‐performance Pt‐free electrocatalysts for hydrogen oxidation reaction (HOR) in alkaline media is highly imperative for the development of alkaline polymer electrolyte fuel cells. Phase engineering is an effective strategy for boosting the catalytic performance of electrocatalysts; however, the fabrication of unconventional polymorphism‐interfaced metal catalysts remains a significant challenge. In this study, a polymorphism‐interfaced Ru nanocatalyst with a stable hexagonal close‐packed (hcp) phase and a metastableface‐centered‐cubic (fcc) phase is successfully prepared. Owing to the built‐in electric field and stacking fault on the unique polymorphic interface, the fcc‐hcp‐Ru catalyst exhibits outstanding alkaline HOR performance with a mass activity of 1016 A gPGM‐1, which is six and three times higher than that of conventional hcp‐Ru andcommercial Pt/C, respectively. The regulated electron distribution at the polymorphic interface is attributed to the discrepant work functions, which not only optimize the adsorption energy of hydrogen but also facilitate the water formation step to promote the alkaline HOR process. This study demonstrates that unconventional polymorphism‐interfaced engineering is an efficient strategy to regulate the electronic structure of metal catalysts and identifies the prominent role of the work function in alkaline HORs, providing a new avenue for the rational design of highly efficient materials for electrocatalysis. [ABSTRACT FROM AUTHOR]

Tumor computed tomography (CT) image segmentation can provide a basis for the determination of tumor location and type. Therefore, it is of great significance to study the automatic segmentation method of tumor CT images. To address the problem of poor segmentation effect of traditional automatic tumor CT images segmentation methods, we propose an automatic segmentation method for tumor CT images using deep convolutional neural networks (DCNNs). First, the CT tumor image is simplified. According to the features of the target region and the background region, the distribution features of the tumor region in the CT images are obtained by convolution calculation, and the feature extraction is completed by feature fusion. Second, based on the feature extraction results, a deep supervised network is constructed to determine the image depth, which lays a solid foundation for accurate segmentation of tumor regions. Finally, DCNN was used to construct automatic segmentation for tumor CT images, which achieves the automatic segmentation of tumor CT images by mode calculation. The results show that the segmented tumor region is close to the actual region and the maximum pixel loss coefficient is 0.07, the maximum segmentation sensitivity is 7865 kbps/s, the pixel segmentation specific coefficient and the segmentation edge distance are kept at a low level, which has a certain application value in the field of tumor CT images. [ABSTRACT FROM AUTHOR]

Ocean mesoscale eddy is a special mesoscale phenomenon in the ocean, which widely exists in all oceans and marginal seas around the world. Compared with ordinary ocean circulation, mesoscale eddy has high rotating speed, strong current velocity, and average vertical depths of several kilometres, which play an important role in ocean circulation and material transport. The traditional mesoscale eddy identification and recognition have great subjectivity and usually depends on the parameters predefined or adjusted by experts, which cannot guarantee the accuracy. With the development of artificial intelligence, deep learning method has also been widely used in the detection and recognition of ocean eddies. Based on the sea-level anomaly (SLA) data provided by Copernicus Marine Environment Detection Service, this study compares the results of the ‘you only look once level feature’ (YOLOF) model and Detectron2 model in deep learning on marine mesoscale eddy detection. The mesoscale eddies in the South China Sea from 2011 to 2013 are detected and identified. The accuracy of Detectron2 model is about 57%, while the accuracy of YOLOF model can reach 90%. Comparing the performance of the two models on the same data set, it can be found that YOLOF model improves the accuracy and speed of recognition to a certain extent. The deep learning network model provides an effective technical method for the study of mesoscale eddy detection by sea surface height. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Unveiling the role of adsorbed hydroxide involved in the hydrogen oxidation reaction (HOR) under alkaline electrolyte is crucial for the development of advanced HOR electrocatalysts for the alkaline polymer electrolyte fuel cells (APEFCs). Herein, we report the synthesis of amorphous RuCr nanosheets with different molar ratios and their HOR performances under alkaline media. We find a volcano correlation between the Cr content in RuCr nanosheets and their alkaline HOR performance. Experimental results and density functional theory (DFT) calculation reveals that the optimized Cr content in RuCr nanosheets could lead to the optimum hydroxide binding energy (OHBE), contributes to their remarkable alkaline HOR performance with mass activity of 568.1 A·gPGM–1 at 50 mV, 13‐fold higher than that of Ru catalyst. When RuCr nanosheet is further used as the anodic electrocatalyst, a peak power density of 1.04 W·cm–2 can be achieved in an APEFC. [ABSTRACT FROM AUTHOR]

In view of the problems of low measurement accuracy and repeated calibration during the use of coal mine water quality analysis, the hyperspectral reflection noncontact measurement technology was proposed to solve the existing problems. KCl, NaCl, pH, NaHCO3, and CaCl2were used to indicate the characteristic ion information of Na+, K+, Ca2+, Cl−, HCO3−, and pH mine water in the laboratory, and 2220 spectral data were obtained by spectral determination. Savitzky–Golay convolution smoothing was used to smooth and denoise the original spectral data of each ion, and the relationship between the spectrum and the concentration of each reagent was obvious after smoothing and denoising pretreatment. The principal component regression method was used to build the inversion model of each ion content, and through the modeling study, the prediction set of KCl was found: the coefficient R∧2 reaches 0.907, RPD is up to 2.7; the prediction set of NaCl was found: the coefficient R∧2 reaches 0.957, RPD is up to 3.1; the PH prediction set was found: the coefficient R∧2 reaches 0.785, RPD is up to 2.1; the prediction set of NaHCO3 was found: the coefficient R∧2 reaches 0.137, RPD is up to 1.2; the prediction set of CaCl2 was found: the coefficient R∧2 reaches 0.622, and RPD is up to 1.7. The results show that the hyperspectral method can play a better role in the extraction of K+, Cl−, Na+, Ca2+, and pH. It is difficult to extract HCO3− ions. [ABSTRACT FROM AUTHOR]

One of the approaches for numerical prediction of the ship maneuvering in still water is based on the lifting theory. In this paper, a numerical method for the fast prediction of the maneuvering motion of the trimaran in still water is developed based on the Source and Quasi Continuous Vortex Lattice Method (SQCM). By the SQCM, the captive model test of the trimaran could be simulated, and the corresponding hydrodynamic coefficients could be obtained. Combined with the MMG maneuvering motion model, the rapid forecasting of the maneuvering motion characteristics of the trimaran is realized. The numerical method is validated by comparison with the tank test, and the turn and zigzag maneuvers of trimaran of different side-hull arrangements at various speeds are predicted. • The captive model test of the trimaran are simulated to obtain the force, moment, and hydrodynamic derivatives by the SQCM method. • The turn and zigzag maneuvers of the trimaran are predicted by the MMG model and the hydrodynamic derivatives. [ABSTRACT FROM AUTHOR]

Aqueous Zn-ion batteries (AZIBs) with excellent electrochemical performance are achieved by using small organic molecules VO(acac) 2 (IV) as cathode. The surface area and electrical conductivity of IV are increased by coating wrinkled rGO, thereby improving the electrochemical sluggishness of IV cathode. The VO(acac) 2 @rGO (IV@rGO) aqueous battery can display a high capacity of 327.2 mAh g−1 at 100 mA g−1. The Zn2+ and H+ con-insertion/extraction reactions within IV@rGO are a joint control of pseudocapacitance and diffusion process. The in-situ XRD combinded with ex-situ Raman and XPS reveal that the multivalent transition of vanadium and coordination reaction of organic functional groups (V O), and no significant volume change of IV structure implying near-zero expansion characteristic during charging/discharging process. • Wrinkled rGO coating is used to alleviate the dissolution of VO(acac) 2 cathode. • H+/Zn2+ co-insertion and oxygen defects lead to ultrafast ion diffusion kinetics. • High capacity comes from the multielectron reaction of vanadium and organic groups. • Structural evolution during charge/discharge shows nearly zero expansion feature. • Low solubility and nearly zero expansion guarantee favorable cycle stability. [ABSTRACT FROM AUTHOR]

The coupled motion of roll and pitch is noticeable when trimaran sails in oblique head waves, which will lead to negative influence on the safety and comfort of navigation. In this paper, the numerical simulation of the trimaran's motion in oblique waves was carried out by open source CFD tool OpenFOAM, and the computed motion response was analyzed to study the characteristics of the torsional rolling. The OpenFOAM-based hybrid method used in this paper was briefly introduced first, and the numerical method was validated and verified by both the grid convergence test and the comparison with experimental result. Both the amplitude and the time history of the computed motion are used for analysis, and the influence of wave steepness, wave heading and forward speed of trimaran on the characteristics of torsional rolling was investigated. The result shows that the large wave steepness and the low forward speed will lead to dangerous torsional rolling motion of trimaran in oblique waves, and the dangerous condition is mainly caused by nonlinear rolling motion; the motion state is more sensitive and changing obviously with other factors at large wave steepness wave conditions. [ABSTRACT FROM AUTHOR]

• The mechanisms of crack initiation, propagation, and evolution during LNCFT are revealed. • The phased effects of crack formation and contact angle variation during the LNCFT process are proposed. • The influence and control mechanism of the LNCFT on the solid–liquid surface contact angle are elucidated. Liquid nitrogen cyclic freezing-thawing fracturing (LNCFT) is an innovative method for the waterless fracturing of coal and rock, harnessing the effects of low temperature, phase change, and expansion. However, the mechanisms behind micro-fracture propagation, evolution, and surface modification during LNCFT remain elusive. This study concentrates on anthracite coal and roof shale in the Jiaozuo mining area. It conducts LNCFT experiments under various saturated water conditions and employs a stereoscopic fluorescence microscope and an optical contact angle measuring instrument for observations, analyzing the surface modification effects resulting from the propagation and evolution of fractures on solid surfaces. The study unveils the following findings: (1) LNCFT effectively creates a network of micro-fractures. The quantity and length of fractures significantly increase with the number of fracturing cycles, and the effect is more pronounced with higher water content, especially in coal compared to shale. Fracture evolution falls into three categories: extension, intersecting, and newly formed independent fractures, with the scale of extension and intersecting of the original fractures determining the modification effect. (2) The LNCFT process exhibits distinct stages and selectivity. The strength of early-stage modifications (before eight cycles) directly influences the overall modification effect. (3) Throughout the LNCFT process, the solid–liquid surface contact angle first increases and then decreases with the number of fracturing cycles. This pattern can be analyzed using the Wenzel model. Liquid nitrogen fracturing increases the surface roughness of coal and shale, leading to a transition from hydrophobicity to hydrophilicity on their surfaces. The research findings of this paper provide theoretical guidance for the modification of low-permeability reservoirs. [ABSTRACT FROM AUTHOR]

• The nanopores expansion effect during the metamorphism-deformation process of tectonic coal is demonstrated through organic solvent extraction experiments. • The impact of small molecular structures on coal pore recombination and their consequent inhibition of gas adsorption is analyzed. • The evolution pattern and driving mechanism of small molecular structures during the deformation process of tectonic coal are revealed. This work aimed to investigate the impact of the evolution of small molecular structures during the deformation of coal on the constraints imposed on nanoscale pores and adsorption behaviors. Both undeformed and tectonically deformed coal (TDC) from the Huaibei mining area in China were collected for analysis. The pyridine was employed for the extraction of small molecules from coal, which was further complemented by Fourier-transform infrared spectroscopy (FTIR) and low-pressure CO 2 and N 2 adsorption experiments (LP-CO 2 /N 2 AD). The study yielded the following results: (1) Intense tectonic stresses facilitate the removal and recombination of small molecular side chains within the basic structural units (BSU) of coal. As deformation occurs, hydroxyl groups, aliphatic hydrocarbons, C=O, C=C, aromatic hydrocarbons, and 'C' structures tend to accumulate, resulting in an enhanced extraction rate. (2) The deformation process of the coal demonstrates a significant pore-expansion effect, with the most substantial increase observed in micropores (surface area increased by over 70 %), followed by mesopores and macropores. This enlargement facilitates the aggregation of small molecules and gas storage. (3) Intense deformation stages involving shear slip, ductile deformation, and maceral fragmentation result in small molecular fractures and an increased number of micropores. The removal and recombination of I, DOC, and CH 2 /CH 3 within BSUs lead to the formation of larger interconnected pores accompanied by the aggregation of hydroxyl groups (OH–), C=O, C=C, aliphatic hydrocarbons, and 'C' structures. (4) The adsorption capacity of residual coal is lower than that of the raw coal before extraction, indicating that small molecular structures contribute to increased adsorption. This likely plays a significant role in the higher gas content observed in structurally deformed coal. The removal of small molecular structures effectively diminishes the adsorption capacity, providing novel perspectives for coalbed methane development and gas extraction in TDC areas. [ABSTRACT FROM AUTHOR]

Food-grade Pickering high internal phase emulsions (HIPEs) stabilized by a mixture of β-cyclodextrin (β-CD) and sugar beet pectin (SBP) were fabricated for the first time. The factors affecting the microstructures, mechanical properties, and stabilities of the Pickering HIPEs were systematically investigated. The corresponding hybrid particles were also separated and characterized to reveal the formation mechanism. The results indicated that the mixture could induce the formation of HIPEs with an oil phase volume fraction (φ) of 75% using a one-step high-speed shearing process at room temperature. The composition (the mass ratio of β-CD to SBP, R c / s) and concentration (W) of the mixture had significant effects on the formation and properties of HIPEs. When W ≥ 1.0% and R c / s = 2:2 or 3:1, HIPEs had smaller oil droplets, higher gel strengths, better centrifugation stabilities and lutein protection effects. The spectral analysis suggested that SBP could adhere to the surface of β-CD particles to form hybrid particles during the homogenization. Compared with native β-CD particles, these hybrid particles had higher ζ-potential absolute values, and the SBP could also increase the viscosity of the aqueous phase, which contributed to the formation and properties of these HIPEs. [ABSTRACT FROM AUTHOR]

Based on CFD method, the numerical method for the manoeuvre simulation of trimaran and asymmetric twin hull by OpenFOAM was applied in this paper. The grid independency test was carried out, and the computed result of turn and zigzag manoeuvres was compared with the result of self-propulsion experiment to validate the numerical method. Then, the numerical method was applied to simulate the turn and zigzag manoeuvres of both an actual trimaran and an actual asymmetric twin hull. By the manoeuvre simulation in calm water with hull attitude fixed and free, the effect of hull attitude on the manoeuvre of trimaran and asymmetric twin hull with different layouts and Froude number was discussed, and the importance of hull attitude for the numerical simulation of turn and zigzag manoeuvres was illustrated. The result shows that, the numerical method in this paper is valid for the manoeuvre simulation of trimaran and asymmetric twin hull, and it makes sense to take the hull attitude into account for the manoeuvre simulation of trimaran and asymmetric twin hull. [ABSTRACT FROM AUTHOR]

Designing a ship hull to keep the hydrodynamic performance meet the requirements is an indispensable step in the ship's preliminary design. However, in the traditional design process, the design workload is labor-intensive and time-consuming due to the need to estimate a large number of design schemes. To address this issue, this work developed a Neural Network Proxy Model (NNPM) to assist the hydrodynamic resistance prediction for the ship hull design process. The data used in the NNPM construction was supported by two Computational Fluid Dynamic (CFD) methods with different fidelity where the low-fidelity one for tuning and pre-training, and the high-fidelity one for fine-training. To mitigate the risk of overfitting stemming from disparities in data volumes, the parameter freezing strategy is adopted during the high-fidelity dataset-based fine-training. The results obtained from validation numerical experiments indicated that the NNPM exhibited a forecast error of less than 1% when compared to the high-fidelity CFD method. Importantly, this high accuracy is achieved while maintaining a low construction workload, demonstrating the potential of Artificial Intelligence (AI) to predict the hydrodynamic load of hulls in the ship's preliminary design, which can further advance the artificial intelligence-assisted design (AIAD) technology for various marine structures. [ABSTRACT FROM AUTHOR]

A low-profile, directive, high-power, simple radio frequency (RF) source can play a crucial role in long-distance communication, sensing, and anti-interference research. Conventional approaches to achieving high-power radiation require a microwave source, an amplifier, and a separate radiating structure. In this article, we transform a static voltage to electromagnetic radiation, which can be electronically steered, using only a thin sheet of metasurface. The proposed approach can be scaled in both power and frequency. The concept makes use of the k = 0 mode in a periodic resonant surface to excite a series of phase-locked individual sources on the surface. The phase-locked sources create an overall coherent mode in the far-field toward the desired direction. The proposed idea is inspired by spark-gap transmitters, pulsed ring-down sources, and antenna arrays to provide a novel and highly scalable electromagnetic source. We envision that the proposed active metasurface for converting a static field to electromagnetic radiation can be potentially used in long-range communication, sensing devices, and radars. [ABSTRACT FROM AUTHOR]

Gong, J.; Li, Y.; Jiang, F.; Hong, Z., and Yu, D., 2020. Maneuvering simulation and study on the effect of hull attitude on maneuverability of trimarans by OpenFOAM. Journal of Coastal Research, 36(1), 157–173. Coconut Creek (Florida), ISSN 0749-0208. Based on open-source code OpenFOAM, the turn and zigzag maneuvers of the trimaran with hull attitude free and fixed are simulated at different Froude numbers in calm water. By the simulation results, the effect of hull attitude on the maneuver characteristics of the trimaran is analyzed and discussed. Two trimaran models are used in this paper for simulation. First, the grid uncertainty test about the turn and zigzag maneuver in calm water is carried out, and the computed results of turn and zigzag maneuvers in calm water are compared with the experimental results to validate the numerical method. Then, the simulation result with free hull attitude is compared with that with fixed hull attitude. The result demonstrates that the hull attitude has significant effect on the maneuverability of the trimaran, especially when the Froude number gets larger and the longitudinal position of the side hulls is in the middle of the center hull. [ABSTRACT FROM AUTHOR]

This paper describes the application of computational fluid dynamics rather than a towing tank test for the prediction of hydrodynamic derivatives using a RANS-based solver. Virtual captive model tests are conducted, including an oblique towing test and circular motion test for a bare model scale KVLCC2 hull, to obtain linear and nonlinear hydrodynamic derivatives in the 3rd-order MMG model. A static drift test is used in a convergence study to verify the numerical accuracy. The computed hydrodynamic forces and derivatives are compared with the available captive model test data, showing good agreement overall. Simulations of standard turning and zigzag manoeuvres are carried out with the computed hydrodynamic derivatives and are compared with available experimental data. The results show an acceptable level of prediction accuracy, indicating that the proposed method is capable of predicting manoeuvring motions. [ABSTRACT FROM AUTHOR]

The longitudinal motion characteristics of a slender trimaran equipped with and without a T-foil near the bow are investigated by experimental and numerical methods. Computational fluid dynamics (CFD) method is used in this study. The seakeeping characteristics such as heave, pitch and vertical acceleration in head regular waves are analyzed in various wave conditions. Numerical simulations have been validated by comparisons with experimental tests. The influence of large wave amplitudes and size of T-foil on the longitudinal motion of trimaran are analyzed. The present systematic study demonstrates that the numerical results are in a reasonable agreement with the experimental data. The research implied that the longitudinal motion response values are greatly reduced with the use of T-foil. [ABSTRACT FROM AUTHOR]

Based on the potential flow theory and traditional boundary element method (BEM), Taylor expansion boundary element method (TEBEM) is introduced in this paper for the prediction of the flow field around ship, as a result, hull gesture and pressure distribution on hull surface are obtained. By this method, dipole strength of every field point is expanded in Taylor expansion, so that approximately continuous hull and free surface boundary condition could be achieved. To close the new equation system, the boundary condition of tangent velocity in every control point is introduced. With the simultaneous solving of hull boundary condition and free surface condition, the disturbance velocity potential could be obtained. The present method is used to predict the flow field and hull gesture of Wigley parabolic hull, Series 60 and KVLCC2 models. To validate the numerical model for full form ship, the wave profile, the computed hull gesture and hull surface pressure of KVLCC2 model are compared with experimental results. [ABSTRACT FROM AUTHOR]

In this study, a methodology was presented to predict density stratified flows in the near-field of submerged bodies. The energy equation in temperature form was solved coupled with momentum and mass conservation equations. Linear stratification was achieved by the definition of the density as a function of temperature. At first, verifications were performed for the stratified flows passing a submerged horizontal circular cylinder, showing excellent agreement with available experimental data. The ability of the method to cope with variable density was demonstrated. Different turbulence models were used for different Re numbers and flow states. Based on the numerical methods proposed in this paper, the stratified flow was studied for the real scale benchmark DAPRA Suboff submarine. The approach used the VOF method for tracing the free surface. Turbulence was implemented with a k − ω based Detached Eddy Simulation (DES) approach. The effects of submarine speed, depth and density gradient on the free surface wave pattern were quantitatively analyzed. It was shown that, with the increasing of the speed of the submarine, the wavelength and wave height of the free surface wave were gradually increasing. The wave height of the free surface wave was gradually reduced as the submarine's depth increased. Relative to the speed and submarine depth, the changes of the gradient density gradient have negligible effects on the free surface wave field. [ABSTRACT FROM AUTHOR]

We propose a method to generate microwave holograms using impedance metasurfaces for multiple simultaneous wavelengths. For recent impedance hologram designs in the microwave band, radiation from leaky waves can be controlled in the far field by creating holograms based on the interference of reference and object waves at a specific frequency. In our design, we vary only one physical dimension in the unit cell to simultaneously satisfy the requirement of impedance distribution for two frequencies in the same aperture. Two excitation ports are used to simultaneously generate the beams at 17 and 20 GHz. The simulation and measurement results show a very good agreement, confirming the validity of the proposed design method. The new low-profile holographic leaky-wave antenna has potential applications in designing multifrequency communication and radar systems. [ABSTRACT FROM AUTHOR]

Metformin is among the most widely used antidiabetic drugs. Studies over the past few years have identified multiple novel molecular targets and pathways that metformin acts on to exert its beneficial effects in treating type 2 diabetes as well as other disorders involving dysregulated inflammation and redox homeostasis. In this mini-review, we discuss the latest cutting-edge research discoveries on novel molecular targets of metformin in glycemic control, cardiovascular protection, cancer intervention, anti-inflammation, antiaging, and weight control. Identification of these novel targets and pathways not only deepens our understanding of the molecular mechanisms by which metformin exerts diverse beneficial biological effects, but also provides opportunities for developing new mechanistically based drugs for human diseases. [ABSTRACT FROM AUTHOR]

Torsional motion is an important motion state to Trimaran caused by the significant coupled motion between pitch and roll. Based on viscous flow theory, the present research predicts the motion of Trimaran in oblique wave conditions by the open-sourced CFD code OpenFOAM. The torsional motion states of Trimaran are analyzed based on the numerical results. Three kinds of coupled motion have been classed, and the motion characteristic of each motion state is studied. On this basis, the most dangerous reciprocated coupled motion has been studied emphatically. Furthermore, the coupled motion states of Trimaran are analyzed in oblique head wave s and oblique stern wave, respectively. The results of the research shows that torsional motion states is more easily to occur in oblique head seas. Especially in high frequency wave conditions, the motion state is prone to dangerous reciprocating coupled motion. The analysis of motion characteristics is significant to trimaran's hydrodynamic research and the vessel's navigation safety. • New analysis methods have been used to find out the real navigation states about trimaran's torsional motion. • Different kinds of coupled motion have been classed. The characteristics of different motion states have been analyzed. • Some dangerous trosional states of trimaran in different wave heading conditions are analyzed respectively. [ABSTRACT FROM AUTHOR]

The trimaran is a high-performance ship of excellent seakeeping performance and stability, which makes it less vulnerable to capsizing. In recent years, strong survivability has increased the applicability of trimaran in unmanned ships. However, compared with the stability and seakeeping, side hulls and the larger width make the trimaran's maneuverability not as good as the traditional monohull. The unified study on trimaran's course keeping and broaching in waves is still limited. In this paper, the navigation of trimaran in oblique stern waves is simulated, and the force and moment by the water-jet impetus and nozzle reflection are simplified. The hybrid method coupling FNPT and CFD is applied to simulate the process of surf-riding and broaching. The characteristics of the surf-riding and broaching of the autopilot trimaran in oblique stern waves are analyzed by changing the working condition of initial forward speed, wave parameters, and initial wave heading. • A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate the autopilot of a trimaran in oblique stern waves. The process of the surf-riding and broaching of trimaran in oblique stern waves could be captured. • The surf-riding and broaching of the autopilot trimaran in oblique stern waves of different steepness and wavelength are simulated, and the effect of the wave steepness and wavelength on the occurrence of surf-riding and broaching of trimaran are analyzed. [ABSTRACT FROM AUTHOR]

In this paper, a hybrid method coupling potential flow method and viscous flow method is applied to simulate the autopilot trimaran in stern waves. The aim is to study the process of being captured by waves and the surf-riding characteristics of the trimaran. The FNPT-based QALE-FEM is used to simulate the wave tank of the external field, and the viscous flow method is used to simulate the autopilot of the trimaran in the wave tank. The sailing and 6DOF motion of the trimaran in waves of different parameters is simulated. The autopilot of a trimaran in stern waves of different lengths and steepness is simulated to study the characteristics of the trimaran's surf-riding in waves. When studying the effect of wave steepness, the wavelength is constant, and various forward speeds of trimaran could change the encounter frequency. However, the trimaran's wave steepness and forward speed are kept constant when the wavelength changes. By the computed results, it is found that the high speed and large wave steepness could significantly increase the vulnerability of trimaran's surf-riding in stern waves, and the wave passing the transom stern and side hulls could accelerate the trimaran to reach the wave celerity. • A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate the navigation of trimaran in stern waves. An external domain by FNPT-based QALE-FEM is used to simulate a numerical wave tank. An internal domain by viscous flow method is used to simulate the trimaran's autopilot with the 6DOF motion taken into account. • By numerical simulation of the trimaran's autopilot in stern waves, the effect of the wave steepness, wavelength and initial speed of the trimaran on the surf-riding of trimaran was studied. • The process of the trimaran's motion in stern waves during the surf-riding was obtained, and the phenomenon before and after the surf-riding is analyzed by changing the wave celerity and trimaran's initial speed. [ABSTRACT FROM AUTHOR]

In this paper, based on the open-source code OpenFOAM, a hybrid method coupling the FNPT-based QALE-FEM and the viscous flow method is used to simulate the turn and zigzag maneuvers of the single-screw ship in waves. The external domain adopts the fully nonlinear potential flow theory to simulate the wave tank. The internal domain simulates the interaction between waves and ships by the viscous flow method. The 6DOF motion equations are combined with the propulsive factors in waves to simulate the ship maneuvering during the simulation. The KVLCC2 model is used for numerical simulation. The numerical method is validated by the comparison with the self-propelled maneuvering test. Then, the turning and zigzag maneuvers of the ship in different initial wave headings and wave parameters are simulated, and the influences of wave heading and wave parameters on ship maneuvering are discussed. • The turn and zigzag maneuvers of a one-screw ship is simulated by a hybrid method. During the simulation, the 6DOF motion of the ship are taken into account, and the propulsive factors in waves are used, which could significantly improve the efficiency. The computed results of the trajectory and motion are compared with the experimental results for validation. • By the simulation of turn and zigzag maneuvers in waves, the effect of the initial wave heading, initial speed, and the wavelength on the turn and zigzag maneuvers of ship is studied. [ABSTRACT FROM AUTHOR]

As one of the widely used high-performance ships, the hydrodynamic characteristics of the trimaran ships have been widely investigated in recent years. But, the study on the maneuverability and the skill of the maneuvering simulation are still limited. In this paper, a hybrid method coupling the FNPT-based (fully nonlinear potential flow theory) QALE-FEM (quasi arbitrary Lagrangian-Eulerian finite element method) with the viscous flow method is applied to simulate the turn and zigzag maneuvers of the trimaran in both calm water and waves. The environment of calm water and incident waves is simulated by the numerical tank of QALE-FEM. The maneuvering of the trimaran is carried out in the scope of the numerical tank by the viscous flow method. The grid convergence test is carried out first, and the computed results are compared with the experimental results. Then, the turn and zigzag maneuvers of a trimaran model in both calm water and waves are simulated to study the trimaran's maneuvering characteristics. 1) A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate turn and zigzag maneuvers of a trimaran in both calm water and head waves. An external domain by FNPT-based QALE-FEM is used to simulate a numerical tank. An internal domain by viscous flow method is used to simulate the maneuvering of the trimaran, which could take the nonlinear effect into accounts, such as green water and side-hull intermittent emergence. 2) The turn and zigzag maneuvers in calm water and waves are simulated, and the effect of the speed on the turn and zigzag maneuvers are analyzed. 3) By numerical simulation of trimaran's maneuver in waves, the effect of wavelength and wave steepness on the maneuverability of the trimaran was studied. [ABSTRACT FROM AUTHOR]

• High internal phase emulsions based on lysozyme and dihydromyricetin were fabricated. • The mixture played a synergistic emulsifying role at the oil–water interface. • The emulsion properties were affected by the mixture composition and addition amount. • Dihydromyricetin and lysozyme failed to form a typical host–guest supramolecule. • Molecular simulation confirmed dihydromyricetin could absorb on the lysozyme surface. This study evaluated the feasibility of fabricating food-grade HIPEs using a dihydromyricetin and lysozyme mixture. The effects of the oil phase volume fraction (φ), composition (lysozyme:dihydromyricetin, k), and addition amount (w) of the mixture on the formation and properties of the HIPEs were analyzed. Then, the interactions of dihydromyricetin and lysozyme were investigated. The results indicated that when w was 0.4%, HIPEs with φ value of 90% could be obtained. Furthermore, the k also affected the microstructure, mechanical properties, oil oxidation, and lutein protection ability of the HIPEs. However, the presence of dihydromyricetin did not affect lysozyme activity. Both isothermal titration calorimetry and molecular simulations proved that they did not form a typical host–guest complex. But, dihydromyricetin could absorb on the lysozyme surface. Therefore, we speculated that lysozyme and dihydromyricetin particles could overlap and form a 3D network structure to stabilize the HIPEs, which was consistent with the microstructure observations. [ABSTRACT FROM AUTHOR]

Tectonically deformed coal (TDC) develops because of the superimposed deformation and metamorphism of a coal seam by tectonic movements. The migration and accumulation of trace elements in TDC is largely in response to stress-strain conditions. To develop a law governing the migration and aggregation of sensitive elements and investigate the geological controls on TDC, coal samples from different deformation sequences were collected from the Haizi mine, in the Huaibei coalfield in Anhui Province, China, and the concentrations of 49 elements were determined by XRF and ICP-MS, and then microscopically analyzed. The results show that the distribution and morphology of minerals in coal is related to the deformation degree of TDC. The evolutionary process runs from orderly distribution of minerals in a weak brittle deformed coal to disordered distributions in ductile deformed coal. According to the elemental distribution characteristics in TDC, four types of element migration can be identified: stable, aggregate, declining, and undulate types, which are closely related to the deformation degree of TDC. Present data indicate that the overall distribution of rare earth elements (REE) does not change with metamorphism and deformation, but it shows obvious dynamic differentiation phenomena along with the deformation of TDC. Tectonic action after coal-formation, brittle or ductile deformation, and the metamorphic mechanism and its accompanying dynamic thermal effects are the main factors that influence the redistribution of elements in TDC. We conclude that tectonic movements provide the motivation and basis for the redistribution of elements and the paths and modes of element migration are controlled by brittle and ductile deformation metamorphic processes. The dynamic thermal effect has the most significant effect on coal metamorphism and tectonic-stress-accelerated element migration and accumulation. These factors then induce the tectonic-dynamic differentiation phenomenon of element migration. [ABSTRACT FROM AUTHOR]

Coupled motion is an important factor that affects the safety and stability of ships sailing in waves, especially for rolling coupled with pitch motion. This paper simulates the motions of trimaran in waves and analyzes the motion characters. The open sourced CFD code OpenFOAM is used to predict the trimaran's motions in oblique head waves, oblique stern waves and beam waves. The grid convergence analysis and the comparison with experimental results are carried out to verify the numerical method. Focusing on the coupled motion characteristics and the stability of trimaran under different waves, a comparative analysis of the trimaran's motion state is made. The changing laws of coupled motion characteristics with different forward speed, wave steepness, wavelength and wave headings are studied. The results show that the trimaran has the largest coupled motion of rolling and pitch in the oblique head waves, but the motion is relatively regular and stable; the trimaran has a relatively poor performance in several wave conditions of oblique stern waves and beam waves. Some wave conditions are easily to cause the unstable rolling motion, especially in small wavelength conditions. 1. The research studies trimarans' coupled motion characteristics based on CFD method, which is different with the study method used by other researchers before, such as multi scale perturbation analysis or Taylor expansion method of the coupled factor in motion equations. The CFD results can describe the motion states more intuitively than the frequency domain methods. 2. The research studies the important roll-pitch coupled motion states of trimaran which is important to the vessel because of the existence of side hulls. While the phenomenon has not been studied by the previous researches. 3. The rolling stability of trimaran is compared at different wave headings based on the CFD results. At this point, some good sailing navigation strategies have been given. [ABSTRACT FROM AUTHOR]

As a kind of high-performance ship, compared with traditional mono-hull, the side-hull position of a trimaran plays an essential role in the hydrodynamics and motion characteristics, which is more significant for the seakeeping performance of a trimaran in waves of different headings. In this paper, the moving forward of trimaran in waves of various headings was simulated by a hybrid numerical method, which combines the fully nonlinear potential flow theory and viscous flow theory. The numerical method was validated firstly. Then, the trimaran model with two different layouts was obtained by increasing the hull separation and moving the side hulls forward. Finally, the motion of the trimaran with different layouts in waves of various headings was simulated, and the effect of layout on the motion response and added resistance were investigated. • A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to study the influence of side hull position on the seakeeping performance of the trimaran in waves, and the wave heading ranges from head wave to stern wave. • To move the side hull forward could reduce the roll motion of trimaran in most working conditions, which is not as predicable as the effect of hull separation on the roll motion. • The hull separation has little effect on the added resistance and motion of trimaran in waves. The main advantage of larger hull separation is to reduce the roll motion of trimaran. • The effect of the side hull position will get less noticeable when the wave steepness or wave length getting larger. [ABSTRACT FROM AUTHOR]

Background: Glioma is a type of tumor that develops in the central nerve system, mainly the brain. Alterations of genomic sequence and sequence segments (such as copy number variations or CNV and copy neutral loss of heterozygosities or cnLOH) are thought to be a major determinant of the tumor grade. Methods: We mapped genomic variations between low-grade and high-grade gliomas (LGG and HGG) in Chinese population based on Illumina’s Beadchip and validated the results using real-time qPCR. Results: At the cytoband level, we discovered: (1) unique losses in LGG on 5q, 8p and 11q, and in HGG on 6q, 11p, 13q and 19q; (2) unique gains in the LGG on 1p and in HGG at 5p, 7p, 7q and 20q; and (3) cnLOH in HGG only on 3q, 8q, 10p, 14q, 15q, 17p, 17q, 18q and 21q. Subsequently, we confirmed well-characterized oncogenes among tumor-related loci (such as EGFR and KIT) and detected novel genes that gained chromosome sequences (such as AASS, HYAL4, NDUFA5 and SPAM1) in both LGG and HGG. In addition, we found gains, losses, and cnLOH in several genes, including VN1R2, VN1R4, and ZNF677, in multiple samples. Mapping grade-associated pathways and their related gene ontology (GO) terms, we classified LGG-associated functions as “arachidonic acid metabolism”, “DNA binding” and “regulation of DNA-dependent transcription” and the HGG-associated as “neuroactive ligand-receptor interaction”, “neuronal cell body” and “defense response to bacterium”. Conclusion: LGG and HGG appear to have different molecular signatures in genomic variations and our results provide invaluable information for the diagnosis and treatment of gliomas in patients with variable duration or diverse tumor differentiation. [ABSTRACT FROM AUTHOR]

Effective use of okara (soybean residue) requires more application aspects to increase its value. The production of enzyme preparations by okara fermented may be an effective approach. In this paper, Bacillus natto was used in okara fermentation to investigate the production of certain enzymes including nattokinase. The results showed that the fermented okara by B. natto produced a large amount of nattokinase and α‐amylase. After the response surface optimization, the nattokinase activity(189.3 IU/mg) and the α‐amylase activity (7.8 U/mg) were obtained at the 36 h fermentation time, the rotation speed 170 rpm, the inoculation amount 9%. After simple two‐step purification, ammonium sulfate precipitation and Sephadex G‐200 column chromatography, the activities of these two enzymes reached 1663.9 IU/mg and 39.93 U/mg, respectively. In short, this research provides a theoretical basis for expanding the application of okara as a low‐cost enzyme preparation. Novelty impact statement: The co‐production of nattokinase and α‐amylase from fermented okara by Bacillus natto can effectively increase the added value of okara. Meanwhile this research provides a theoretical basis for expanding the application of okara as a low‐cost enzyme preparation. [ABSTRACT FROM AUTHOR]

Abstract: The nonlinear absorption can produce a nonlinear image very similar with the one created by the nonlinear refraction when using the nonlinear-imaging technique with phase object to measure the third-order nonlinearity of materials, but the principles of them are different. The formation of the nonlinear absorption image is explained, and the condition that the highest sensitivity of the nonlinear absorption measurement can be reached is deduced. For the materials with both nonlinear absorption and refraction, we find a proper phase shift of the phase object where the effect of the nonlinear refraction to the measured signal can be eliminated. The nonlinear absorption and refraction are numerically simulated when the phase shift of phase object to be π/2 that is normally used. The qualitative tendency of the signal variation is presented. [Copyright &y& Elsevier]

Abstract: We numerically analyze the effects of radius and phase shift of phase objects on the diffraction image of the 4f coherent imaging system, a system used for measuring the third-order nonlinear refractive index. The selection of the aperture radius is discussed. We prove that when the phase object radius is 0.1 time of the aperture radius and the phase change of the phase object is 0.57π, one can get the highest sensitivity for nonlinear refraction measurement. [Copyright &y& Elsevier]

Abstract: Resveratrol (3,4′,5-trihydroxystilbene), a polyphenolic compound found in mulberries, grapes and red wine has been demonstrated to be capable of protecting against oxidative cardiovascular pathophysiology. However, the underlying cellular and biochemical mechanisms remain to be elucidated. This study was undertaken to determine if resveratrol could upregulate endogenous antioxidants and phase 2 enzymes in cultured aortic smooth muscle cells (ASMCs), and if such increased cellular defenses could provide protection against oxidative and electrophilic vascular cell injury. Incubation of rat ASMCs with resveratrol at low micromolar concentrations resulted in a significant induction of a scope of cellular antioxidants and phase 2 enzymes in a concentration- and/or time-dependent fashion. These cytoprotective factors include superoxide dismutase, catalase, glutathione, glutathione reductase, glutathione peroxidase, glutathione S-transferase (GST), and NAD(P)H:quinone oxidoreductase-1 (NOQ1). Notably, induction of catalase, GST, and NOQ1 was most remarkable among the above resveratrol-inducible antioxidants and phase 2 enzymes. Moreover, resveratrol treatment also significantly increased the mRNA expression of catalase, GSTA1, and NQO1 in a time-dependent manner. Pretreatment of ASMCs with resveratrol afforded a remarkable protection against xanthine oxidase (XO)/xanthine- or 4-hydroxy-2-nonenal-induced cytotoxicity, as assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) reduction assay. Resveratrol pretreatment also led to a marked reduction in intracellular accumulation of reactive oxygen species in ASMCs after incubation with XO/xanthine. Taken together, this study demonstrates that a scope of key endogenous antioxidants and phase 2 enzymes in cultured ASMCs can be upregulated by resveratrol at low micromolar concentrations, and that such chemically-elevated cellular defenses rendered cells increased resistance to oxidative and electrophilic stress. The results of this study thus suggested a new mechanism, which might contribute to the cardiovascular protective effects of resveratrol. [Copyright &y& Elsevier]

Abstract: 4-Hydroxy-2-nonenal (HNE) plays an important role in the pathogenesis of cardiac disorders. While conjugation with glutathione (GSH) catalyzed by GSH S-transferase (GST) has been suggested to be a major detoxification mechanism for HNE in target cells, whether chemically upregulated cellular GSH and GST afford protection against HNE toxicity in cardiac cells has not been investigated. In addition, the differential roles of chemically induced GSH and GST as well as other cellular factors in detoxifying HNE in cardiomyocytes are unclear. In this study, we have characterized the induction of GSH and GST by 3H-1,2-dithiole-3-thione (D3T) and the protective effects of the D3T-elevated cellular defenses on HNE-mediated toxicity in rat H9C2 cardiomyocytes. Treatment of cardiomyocytes with D3T resulted in a significant induction of both GSH and GST as well as the mRNA expression of γ-glutamylcysteine ligase catalytic subunit and GSTA. Both GSH and GST remained elevated for at least 72h after removal of D3T from the culture media. Treatment of cells with HNE led to a significant decrease in cell viability and an increased formation of HNE–protein adducts. Pretreatment of cells with D3T dramatically protected against HNE-mediated cytotoxicity and protein–adduct formation. HNE treatment caused a significant decrease in cellular GSH level, which preceded the loss of cell viability. Either depletion of cellular GSH by buthionine sulfoximine (BSO) or inhibition of GST by sulfasalazine markedly sensitized the cells to HNE toxicity. Co-treatment of cardiomyocytes with BSO was found to completely block the D3T-mediated GSH elevation, which however failed to reverse the cytoprotective effects of D3T, suggesting that other cellular factor(s) might be involved in D3T cytotprotection. In this regard, D3T was shown to induce cellular aldose reductase (AR). Surprisingly, inhibition of AR by sorbinil failed to potentiate HNE toxicity in cardiomyocytes. In contrast, sorbinil dramatically augmented HNE cytotoxicity in cells with GSH depletion induced by BSO. Similarly, in BSO-treated cells, D3T cytoprotection was also largely reversed by sorbinil, indicating that AR played a significant role in detoxifying HNE only under the condition of GSH depletion in cardiomyocytes. Taken together, this study demonstrates that D3T can induce GSH, GST, and AR in cardiomyocytes, and that the above cellular factors appear to play differential roles in detoxification of HNE in cardiomyocytes. [Copyright &y& Elsevier]

Spatial decision support systems (SDSS) are a branch of data-driven decision support systems that utilize spatial data in the decision-making process. This paper introduces a simple and inexpensive way of designing SDSS to support property professionals in their decisions concerning locations, throughout the property development process. The proposed SDSS integrate traditional decision support systems with geographical information systems (GIS) to have the best of both worlds: GIS capabilities and modeling ability. The design of the SDSS utilizes two widely used software packages: Excel and MapObjects. Excel is a spreadsheet program that has the strong capability to construct models using its built-in functions and Visual Basic for Application (VBA). MapObjects is a collection of embeddable mapping and GIS components from ESRI. Using these ActiveX automation objects, application developers can add mapping and GIS capabilities to applications. When MapObjects controls are integrated with an Excel sheet, they have the ability to save and show maps, query addresses, and carry out other interactive functions. The development environment and the working mechanism for the proposed systems are introduced, which is further elaborated by providing a case study on how the proposed SDSS can be used by property professionals. [Copyright &y& Elsevier]

Epidemiological studies have conclusively demonstrated that moderate consumption of ethanol is causally associated with a significant reduction in cardiovascular events. However, the exact mechanisms underlying the ethanol-mediated cardiovascular protection remain to be elucidated. Because peroxynitrite has been extensively implicated in the pathogenesis of various forms of cardiovascular disorders via its cytotoxic effects, this study was undertaken to investigate if ethanol could inhibit peroxynitrite-induced DNA strand breaks, a critical event leading to peroxynitrite-elicited cytotoxicity. Toward this goal, φX-174 RF I plasmid DNA was used as an in vitro model to determine the protective effects of ethanol on peroxynitrite-induced DNA strand breaks. Incubation of φX-174 plasmid DNA with the peroxynitrite generator, 3-morpholinosydnonimine (SIN-1) led to the formation of both single- and double-stranded DNA breaks in a concentration- and time-dependent fashion. The presence of ethanol at concentrations ranging from 0.01 to 1% (w/v) resulted in a significant inhibition of SIN-1-induced DNA strand breaks. Ethanol also showed inhibitory effects on SIN-1-induced DNA strand breakage in the presence of bicarbonate. The inhibition of SIN-1-induced DNA strand breaks by ethanol exhibited a concentration-dependent manner. Notably, a marked inhibition of SIN-1-elicited DNA strand breaks was observed with 0.01% ethanol. Ethanol at 0.01–1% was unable to affect SIN-1-mediated oxygen consumption, indicating that ethanol did not affect the auto-oxidation of SIN-1 to form peroxynitrite. Furthermore, incubation of the plasmid DNA with authentic peroxynitrite resulted in a significant formation of DNA strand breaks, which could be dramatically inhibited by the presence of 0.02–0.1% ethanol. Taken together, this study demonstrates for the first time that ethanol at physiologically relevant concentrations can potently inhibit peroxynitrite-induced DNA strand breakage. In view of the critical involvement of peroxynitrite in cardiovascular disorders, the results of this study might have implications for the cardiovascular protection associated with moderate consumption of ethanol in humans. [Copyright &y& Elsevier]

The recognition of the critical involvement of oxidative and electrophilic stress in cardiac disorders has led to extensive investigation of the protective effects of exogenous antioxidants on cardiac injury. On the other hand, another strategy for protecting against oxidative/electrophilic cardiac injury may be through induction of the endogenous antioxidants and phase 2 enzymes in myocardium by chemical inducers. However, our understanding of the chemical inducibility of cardiac antioxidants/phase 2 enzymes in vivo is very limited. In addition, careful studies on the basal levels of a scope of endogenous antioxidants/phase 2 enzymes in myocardium as compared with other tissues, such as liver, are lacking. Accordingly, this study was undertaken to determine the basal levels of endogenous antioxidants/phase 2 enzymes, including superoxide dismutase (SOD), catalase, reduced glutathione (GSH), GSH peroxidase (GPx), glutathione reductase (GR), GSH S-transferase (GST), and NAD(P)H:quinone oxidoreductase 1 (NQO1), and investigate the inducibility of the above antioxidants/phase 2 enzymes by the chemoprotectant, 1,2-dithiole-3-thione (D3T), in cardiac as well as hepatic tissues in C57BL/6 mice. Our results demonstrated that in C57BL/6 mice, the levels of catalase, GSH, GPx, GR, and GST were significantly lower in cardiac tissue than in hepatic tissue. The level of total SOD did not differ significantly between mouse heart and liver. Notably, heart contained a much higher NQO1 activity than liver. Immunoblotting and RT-PCR analyses further demonstrated the high expression of NQO1 protein and mRNA in myocardium. Oral administration of D3T at 0.25 and 0.5 mmol/kg body weight for 3 consecutive days resulted in a significant induction of cardiac SOD, catalase, GR, GST, and NQO1. No significant induction of cardiac GSH and GPx was observed with the above D3T treatment. Only GR, GST, and NQO1 in mouse liver were induced by the D3T treatment. Unexpectedly, we observed a significant D3T dose-dependent decrease in hepatic GPx activity. Taken together, this study demonstrates for the first time that: (1) the expression of NQO1 is remarkably high in mouse myocardium though other cardiac antioxidants/phase 2 enzymes are relatively lower as compared with liver; (2) a number of endogenous antioxidants/phase 2 enzymes in mouse cardiac tissue can be significantly induced by D3T following oral administration; and (3) the inducibility of endogenous antioxidants/phase 2 enzymes by D3T differs between mouse cardiac and hepatic tissues. This study provides a basis for future investigation of the cardioprotection of chemically induced endogenous antioxidants and phase 2 enzymes in myocardium in animal models of oxidative/electrophilic cardiac disorders. [Copyright &y& Elsevier]

Resveratrol is known to be protective against oxidative cardiovascular disorders. However, the underlying mechanisms remain unclear. This study was undertaken to determine if resveratrol could increase endogenous antioxidants and phase 2 enzymes in cardiomyocytes, and if such increased cellular defenses could provide protection against oxidative and electrophilic cell injury. Incubation of cardiac H9C2 cells with low micromolar resveratrol resulted in a significant induction of a scope of cellular antioxidants and phase 2 enzymes in a concentration- and/or time-dependent fashion. To investigate the protective effects of the resveratrol-induced cellular defenses on oxidative and electrophilic cell injury, H9C2 cells were first incubated with resveratrol, and then exposed to xanthine oxidase (XO)/xanthine, 4-hydroxy-2-nonenal or doxorubicin. We observed that resveratrol pretreatment afforded a marked protection against the above agent-mediated cytotoxicity in H9C2 cells. Moreover, the resveratrol pretreatment led to a great reduction in XO/xanthine-induced intracellular accumulation of ROS. Taken together, this study demonstrates that resveratrol induces antioxidants and phase 2 enzymes in cardiomyocytes, which is accompanied by increased resistance to oxidative and electrophilic cell injury. [Copyright &y& Elsevier]

Ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one), a seleno-organic compound with glutathione peroxidase-like activity, has been shown to be protective against brain ischemic injury and Parkinson''s disease. This study was undertaken to investigate the protective effects of ebselen on oxidative DNA damage induced by dopamine in the presence of copper ions. Incubation of φX-174 plasmid DNA with micromolar dopamine in the presence of Cu(II) resulted in a concentration-dependent induction of DNA strand breaks. Both a Cu(II)/Cu(I) redox cycle and H2O2 formation were critically involved in the induction of DNA strand breaks by the dopamine/Cu(II) system. The presence of ebselen at micromolar concentrations led to a marked concentration-dependent inhibition of DNA strand breaks induced by the dopamine/Cu(II) system. Further studies showed that ebselen did not affect either the Cu(II)-mediated oxidation of dopamine to dopamine quinone or the reduction of Cu(II) to Cu(I) by dopamine. Instead, the presence of ebselen resulted in a marked decrease in the levels of H2O2 derived from the Cu(II)-mediated oxidation of dopamine. Taken together, our results demonstrate for the first time that ebselen is able to inhibit the dopamine/Cu(II)-induced oxidative DNA damage, which appears to be attributable to the ability of ebselen to decrease the levels of H2O2 derived from the dopamine/Cu(II) system. Since oxidative DNA damage has been implicated in the pathogenesis of various neurodegenerative diseases, the inhibition of oxidative DNA damage by ebselen may be responsible, at least partially, for its neuroprotective activities observed in both humans and experimental animals. [Copyright &y& Elsevier]

The biotransformation of butylated hydroxyanisole (BHA), a possible carcinogenic food antioxidant, includes o-demethylation to 2-tert-butyl(1,4)hydroquinone (TBHQ) which can subsequently be oxidized to 2-tert-butyl(1,4)paraquinone (TBQ). In this study, we have examined the capacity of Cu, a nuclei- and DNA-associated transition metal, to mediate the oxidation of TBHQ. In phosphate buffered saline (PBS), autooxidation of TBHQ to TBQ was not detectable, while Cu(II) at micromolar concentrations strongly catalyzed the oxidation of TBHQ to TBQ. Oxidation of TBHQ by Cu(II) was accompanied by the utilization of O2 and the concomitant generation of H2O2. Using electron spin resonance spectroscopy, it was observed that Cu(II) mediated the one electron oxidation of TBHQ to a semiquinone anion radical. The formation of a semiquinone anion radical, the utilization of O2 and the generation of H2O2 and TBQ could be completely blocked by bathocuproinedisulfonic acid (BCS) and reduced glutathione (GSH), two Cu(I)-chelators. 4-Pyridyl-1-oxide-N-tert-butylnitrone (POBN)-spin trapping experiments showed that the reaction of TBHQ with Cu(II) resulted in the generation of POBN-CH3 and POBN-CH(OH)CH3 adducts in the presence of dimethyl sulfoxide (DMSO) and ethanol, respectively, suggesting the formation of hydroxyl radical or a similar reactive intermediate. The formation of POBN-CH3 adduct from the TBHQ/Cu(II)+DMSO could be completely inhibited by catalase, GSH or BCS, indicating that the hydroxyl radical or its equivalent is generated from the interaction of H2O2 with Cu(I). Incubation of supercoiled φX-174 plasmid DNA with the TBHQ/Cu(II) resulted in extensive DNA strand breaks, which could be prevented by catalase or BCS. Incubation of rat hepatocytes with TBHQ in PBS led to increased formation of 8-hydroxy-2′-deoxyguanosine (8-OHdG) in nuclear DNA. The TBHQ-induced formation of 8-OHdG was markedly reduced in the presence of cell permeable Cu(I)-specific chelator, bathocuproine or neocuproine, suggesting that a Cu(II)/Cu(I) redox mechanism may also be involved in the induction of oxidative DNA damage by TBHQ in hepatocytes. Taken together, the above results conclusively demonstrate that the activation of TBHQ by Cu(II) results in the formation of TBQ, semiquinone anion radical and reactive oxygen species (ROS), and that the ROS formed may participate in oxidative DNA damage in both isolated DNA and intact cells. These reactions may contribute to the carcinogenicity as well as other biochemical activities observed with BHA in animals. To our knowledge this study provides the first evidence that endogenous cellular Cu may be capable of bioactivating TBHQ, leading to oxidative DNA damage in cultured cells. [Copyright &y& Elsevier]

Considerable evidence suggests that reactive oxygen species (ROS) are crucially involved in the pathogenesis of cardiovascular diseases, such as myocardial ischemia–reperfusion injury. Consistent with this notion, administration of exogenous antioxidative compounds has been shown to provide protection against oxidative cardiac injury. However, whether induction of endogenous cellular antioxidants by chemicals (drugs) also offers protection against oxidative cardiac injury has not been extensively investigated. In the present study, with rat cardiomyocyte H9C2 cells as an in vitro model, we have investigated the induction of cellular antioxidants by the unique chemoprotective agent, 3 H -1,2-dithiole-3-thione (D3T) and the protective effects of the D3T-induced cellular antioxidants against ROS-mediated injury in cardiac cells. Incubation of H9C2 cells with micromolar concentrations of D3T for 24 h resulted in a significant induction of a battery of cellular antioxidants, including reduced glutathione (GSH), GSH peroxidase, GSSG reductase, GSH S-transferase and catalase. To further examine the protective effects of the induced endogenous antioxidants against oxidative cell injury, H9C2 cells were pre-treated with D3T and then incubated with xanthine oxidase (XO) plus xanthine, a system that generates ROS. We observed that D3T pre-treatment of H9C2 cells led to significant protection against XO/xanthine-induced cytotoxicity as determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) reduction and morphological changes. Taken together, this study demonstrates for the first time that a number of endogenous antioxidants in cardiomyocytes can be induced by exposure to D3T, and that this chemical (drug) induction of cellular antioxidants is accompanied by markedly increased resistance to ROS-mediated cardiac cell injury. [Copyright &y& Elsevier]

Epidemiological studies have suggested that the use of aspirin is associated with a decreased incidence of human malignancies, particularly colorectal cancer. Since reactive oxygen species (ROS) are critically involved in multistage carcinogenesis, this study was undertaken to examine the ability of aspirin to inhibit ROS-mediated DNA damage. Hydrogen peroxide (H2O2)+Cu(II) and hydroquinone (HQ) + Cu(II) were used to cause oxidative DNA strand breaks in φX-174 plasmid DNA. We demonstrated that the presence of aspirin at concentrations (0.5–2 mM) compatible with amounts in plasma during chronic anti-inflammatory therapy resulted in a marked inhibition of oxidative DNA damage induced by either H2O2/Cu(II) or HQ/Cu(II). The inhibition of oxidative DNA damage by aspirin was exhibited in a concentration-dependent manner. Moreover, aspirin was found to be much more potent than the hydroxyl radical scavengers, mannitol and dimethyl sulfoxide, in protecting against the H2O2/Cu(II)-mediated DNA strand breaks. Since the reduction of Cu(II) to Cu(I) is crucially involved in both H2O2/Cu(II)- and HQ/Cu(II)-mediated formation of hydroxyl radical or its equivalent, and the subsequent oxidative DNA damage, we examined whether aspirin could inhibit this Cu(II)/Cu(I) redox cycle. It was observed that aspirin at concentrations that showed the inhibitory effect on oxidative DNA damage did not alter the Cu(II)/Cu(I) redox cycle in either H2O2/Cu(II) or HQ/Cu(II) system. In addition, aspirin was not found to significantly scavenge H2O2. This study demonstrates for the first time that aspirin potently inhibits both H2O2/Cu(II)- and HQ/Cu(II)-mediated oxidative DNA strand breaks most likely through scavenging the hydroxyl radical or its equivalent derived from these two systems. The potent inhibition of oxidative DNA damage by aspirin may thus partially contribute to its anticancer activities observed in humans. [Copyright &y& Elsevier]

Extensive evidence suggests that reactive oxygen species are critically involved in the pathogenesis of cardiovascular diseases, such as atherosclerosis and myocardial ischemia–reperfusion injury. Consistent with this concept, administration of exogenous antioxidants has been shown to be protective against oxidative cardiovascular injury. However, whether induction of endogenous antioxidants by chemical inducers in vasculature also affords protection against oxidative vascular cell injury has not been extensively investigated. In this study, using rat aortic smooth muscle A10 cells as an in vitro system, we have studied the induction of cellular antioxidants by the unique chemoprotector, [3H]-1,2-dithiole-3-thione (D3T) and the protective effects of the D3T-induced cellular antioxidants against oxidative cell injury. Incubation of A10 cells with micromolar concentrations of D3T for 24 h resulted in a significant induction of a battery of cellular antioxidants in a concentration-dependent manner. These included reduced glutathione (GSH), GSH peroxidase, GSSG reductase, GSH S-transferase, superoxide dismutase, and catalase. To further examine the protective effects of the induced endogenous antioxidants against oxidative cell injury, A10 cells were pretreated with D3T and then exposed to either xanthine oxidase (XO)/xanthine, 4-hydroxynonenal, or cadmium. We observed that D3T pretreatment of A10 cells led to significant protection against the cytotoxicity induced by XO/xanthine, 4-hydroxynonenal or cadmium, as determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium reduction assay. Taken together, this study demonstrates for the first time that a number of endogenous antioxidants in vascular smooth muscle cells can be induced by exposure to D3T, and that this chemical induction of cellular antioxidants is accompanied by markedly increased resistance to oxidative vascular cell injury. [Copyright &y& Elsevier]

As a commonly used method to evaluate the pore structures of coal, uncorrected MIP data may cause the results to be highly overestimated. In this study, a series of experiments were carried out to characterize the accurate pore structure of coal including MIP, low pressure N 2 /CO 2 adsorption, scanning electron microscopy (SEM) and X-ray computed microtomography (μCT). Base on the process of mercury penetrate the pore by driven-pressure, it is clear that the mercury intrusion under high pressure can induce the coal matrix compression. Meanwhile, the MIP error (from 36.1% to 130.9% of the pore volume) was derived from coal matrix compression at the high pressure, and the interparticle pore and pockmark effects under low pressure. Here, a new and more practical pore volume correction method was proposed by simplifying the coal matrix compressibility calculation. The new method was tested to be valid for the tested coals with comparison of reported corrected data. The relationship model between intrusion pressure of mercury and pore diameter was revised by the pore morphology. The interparticle pores and pockmark effects mainly occur in the pressure range less than 0.01 MPa. In order to minimize the interparticle pores effect and pockmark effect, a new sample preparation method is recommended for MIP test. This study provides a practical approach to characterize the coal pore structure accurately using the MIP technique and the findings are impactful for the future gas transport modeling in various coals. [ABSTRACT FROM AUTHOR]