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The choice of torque curve in lower-limb enhanced exoskeleton robots is a key problem in the control of lower-limb exoskeleton robots. As a human–machine coupled system, mapping from sensor data to joint torque is complex and non-linear, making it difficult to accurately model using mathematical tools. In this research study, the knee torque data of an exoskeleton robot climbing up stairs were obtained using an optical motion-capture system and three-dimensional force-measuring tables, and the inertial measurement unit (IMU) data of the lower limbs of the exoskeleton robot were simultaneously collected. Nonlinear approximations can be learned using machine learning methods. In this research study, a multivariate network model combining CNN and LSTM was used for nonlinear regression forecasting, and a knee joint torque-control model was obtained. Due to delays in mechanical transmission, communication, and the bottom controller, the actual torque curve will lag behind the theoretical curve. In order to compensate for these delays, different time shifts of the torque curve were carried out in the model-training stage to produce different control models. The above model was applied to a lightweight knee exoskeleton robot. The performance of the exoskeleton robot was evaluated using surface electromyography (sEMG) experiments, and the effects of different time-shifting parameters on the performance were compared. During testing, the sEMG activity of the rectus femoris (RF) decreased by 20.87%, while the sEMG activity of the vastus medialis (VM) increased by 17.45%. The experimental results verify the effectiveness of this control model in assisting knee joints in climbing up stairs. [ABSTRACT FROM AUTHOR]

Bacterial infection has been considered as a serious problem posing health and economic risks worldwide. Although certain materials like antibiotics have been widely used as antimicrobial products, their cytotoxicity and drug resistance effect remain challenges. Fullerene (C60) has been proven as a safe antibacterial material via photodynamic therapy (PDT), but its strong hydrophobicity and limited bactericidal efficiency prevent its biomedical application. Herein, we report a facile strategy in producing ultrasmall (ca. 3 nm) zinc nanoparticle-decorated hydroxylated C60 (ZnNPs/fullerenol), which possesses high solubility and stability in water. Efficient antibacterial performances of ZnNPs/fullerenol were achieved under a visible light irradiation for only 15 min that the inhibition rate for E. coli and S. aureus could reach to 99 and 80%, respectively. This is attributed to the strong synergism of ZnNPs and fullerenol, leading to a large radical oxygen species (ROS) generation under visible light. In vivo tests further indicated excellent wound healing functionality of our composite. This work may shed light on the innovation for next generation of nanoscale antibacterial agents. [ABSTRACT FROM AUTHOR]

Holes and defects can greatly reduce the mechanical properties of multilayer graphene sheets under different loading conditions due to the stress concentration near the hole edge in each in-plane sheet and the lack of interlayer carbon–carbon bonds between the layers. Here, we report a novel design of multilayer open-hole graphene papers (MLGPs) formed through interlayer covalent bonding at the hole edges of multilayer open-hole graphene sheets (MLGSs) under high temperature using molecular dynamics (MD) simulations. Our MD results show that the hybrid sp2–sp3 interlayer bonds of MLGPs can significantly improve their both tensile strength and interlayer shear strength. The tensile strength and interlayer shear strength of MLGPs increase by around 20% and 3 times by comparison with those of MLGSs with the same number of layers, respectively, which mainly depends on the uniformity of their interlayer bond distribution. This study can provide an effective way to improve the mechanical performances of multilayer graphene sheets with flaws and also offer corresponding guidance for the design of MLGS-based nanocomposites. [ABSTRACT FROM AUTHOR]

The classification of lower limb gait phase is very important for the control of exoskeleton robots. In order to enable the exoskeleton to determine gait phase and provide appropriate assistance to the wearer, we propose a compound network based on CNN-BiLSTM. The method uses data from inertial measurement units placed on the leg and pressure sensor arrays placed on the sole as inputs to the model. The convolutional neural network (CNN) is used to obtain the local key features of gait data, and then the bidirectional long short-term memory (BiLSTM) network is used to extract the serialized gait phase information from the local key features to obtain the high-level feature expression. Finally, the seven phases of both feet were obtained through the classification of the softmax layer. We designed a gait acquisition system and collected the gait data from seven subjects at varying walking speeds. In the test set, the highest gait phase classification accuracy can reach 95.09%. We compared the proposed model with the long short-term memory (LSTM) network and gated recurrent unit (GRU) network. The experimental results show that the average accuracy of CNN-BiLSTM network from seven subjects is 0.417% higher than that of the LSTM network and 0.596% higher than that of the GRU network. Therefore, the ability of the CNN-BiLSTM network to classify gait phases can be applied in designing exoskeleton controllers that can better assist for different gait phases correctly to assist the wearer to walk. [ABSTRACT FROM AUTHOR]

Natural gas hydrate is a kind of environmentally friendly unconventional energy with large reserves, which attract increasing attention in recent years. The microscopic pore structure and mineral composition of natural gas hydrate reservoir have a great influence on its seepage characteristics during exploitation. In this study, computed tomography and scanning electron microscope are used to obtain digital images of three clayey-silt natural gas hydrate reservoir samples in the Shenhu area of South China Sea, and then, the pore structure and the mineral composition of the samples are obtained after image processing. The result indicates that the clayey-silt samples show strong hydrophilic characteristics, small particles, good sorting properties, variable pore distribution, small average pore and throat radius, large porosity, and a large content of submicron pores. The mineral composition of the reservoir is mainly quartz and contains a certain amount of clay minerals, mainly illite, while the mineral composition of reservoir rich in microbial fossils is mainly carbonate. The results indicate that the pore structure and mineral composition of natural gas hydrate reservoirs in Shenhu area lay a foundation for the efficient development of the clayey-silt reservoir. [ABSTRACT FROM AUTHOR]

Fullerene (C60) has been regarded as an effective radical scavenger for many years, but the highly hydrophobic nature strongly limits its application in biological fields. Herein, a simple and green strategy for synthesizing water-soluble fullerene derivative was reported, in which intrinsic C60 was grafted by amine oxide functional group (AO-C60). In addition to its excellent aqueous dispersion, AO-C60 exhibited extremely low toxicity to mice macrophage cell RAW264.7. Further experiments have confirmed the prominent antioxidative ability of AO-C60 towards typical free radicals including 1,1-diphenyl-2-picrylhydrazy (DPPH) radical, hydroxyl radical (•OH) and nitric oxide (•NO) without the help of metal loading, while the IC50 could be as low as 0.09 mg/mL. Our work will shed light on the development of anti-oxidative nanoagents with both effectiveness and bio-safety. [ABSTRACT FROM AUTHOR]

The Poisson multi-Bernoulli mixture (PMBM) is a multiobject conjugate prior for the closed-form Bayes random finite set filter. The extended object PMBM filter provides a closed-form solution for multiple extended object filtering with standard models. This article considers computationally lighter alternatives to the extended object PMBM filter by propagating a Poisson multi-Bernoulli (PMB) density through the filtering recursion. A new local hypothesis representation is presented, where each measurement creates a new Bernoulli component. This facilitates the developments of methods for efficiently approximating the PMBM posterior density after the update step as a PMB. Based on the new hypothesis representation, two approximation methods are presented: one is based on the track-oriented multi-Bernoulli (MB) approximation, and the other is based on the variational MB approximation via Kullback–Leibler divergence minimization. The performance of the proposed PMB filters with gamma Gaussian inverse-Wishart implementations are evaluated in a simulation study. [ABSTRACT FROM AUTHOR]

The gas-water two-phase seepage process is complex during the depressurization process of natural gas hydrate in a clayey silt reservoir in the South China Sea, the transport mechanism of which has not been clarified as it is affected by the pore structure. In this study, we select six clayey silt samples formed after the dissociation of natural gas hydrate in the South China Sea, employing CT scanning technology to observe the pore structure of clayey silt porous media directly. The original CT scanning images are further processed to get the binarized images of the samples, which can be used for simulation of the porosity and absolute permeability. Based on the fractal geometry theory, pore structures of the samples are quantitatively characterized from the aspect of pore distribution, heterogeneity, and anisotropy (represented by three main fractal geometric parameters: fractal dimension, lacunarity, and succolarity, respectively). As a comparison, the binarized CT images of two conventional sandstone cores are simulated with the same parameters. The results show that the correlation between porosity and permeability of the hydrate samples is poor, while there is a strong correlation among the succolarity and the permeability. Fractal dimension (represents complexity) of clayey silt samples is higher compared with conventional sandstone cores. Lacunarity explains the difference in permeability among samples from the perspective of pore throat diameter and connectivity. Succolarity indicates the extent to which the fluid in the pore is permeable, which can be used to characterize the anisotropy of pore structures. Therefore, these three fractal parameters clarify the relationship between the microstructure and macroscopic physical properties of clayey silt porous media. [ABSTRACT FROM AUTHOR]

Most two-dimensional (2D) materials (such as graphene and black phosphorus (BP)) exhibit the strong anisotropy in their nonlinear mechanical properties. However, it is still a tremendous challenge to modulate their anisotropy for some special applications. In this study, the mechanical anisotropy of graphene and BP can be regulated by controlling their defects (such as circular holes, elliptic holes and cracks) using molecular dynamics simulations, which is reasonable by comparison with available continuum models. For circular-hole defects, the isotropic ratios (λ) of fracture stresses and strains in both graphene and BP are lower than 0.4 when D / L ≥ 0.2 (D and L are the diameter of the circular hole and the boundary length of 2D materials, respectively.), where λ = 0 and λ = 1 represent the complete isotropy and the original anisotropy without defects, respectively. For elliptic-hole and crack defects, λ in both graphene and BP can be close to zero by controlling their sizes and oblique angles. In particular, modulating mechanical anisotropy of 2D materials is further proven by measuring the nonlinear mechanical properties of open-hole paper napkins. This study should be of great help for providing physical insights into the origins of defect-control isotropy of 2D materials. Image 1077433 [ABSTRACT FROM AUTHOR]

Fractal theory has been widely used in petrophysical properties of porous rocks over several decades and determination of fractal dimensions is always the focus of researches and applications by means of fractal-based methods. In this work, a new method for calculating pore space fractal dimension and tortuosity fractal dimension of porous media is derived based on fractal capillary model assumption. The presented work establishes relationship between fractal dimensions and pore size distribution, which can be directly used to calculate the fractal dimensions. The published pore size distribution data for eight sandstone samples are used to calculate the fractal dimensions and simultaneously compared with prediction results from analytical expression. In addition, the proposed fractal dimension method is also tested through Micro-CT images of three sandstone cores, and are compared with fractal dimensions by box-counting algorithm. The test results also prove a self-similar fractal range in sandstone when excluding smaller pores. [ABSTRACT FROM AUTHOR]

The complex and heterogeneous microstructure of underground porous media usually results from geological processes such as deposition, compaction, cementation and fluid-mineral interactions. Variations in these microstructural characteristics largely determine the differences in the transport properties of porous media. The fractal geometry theory has been successfully applied to characterize the microstructure and transport properties of underground reservoirs. In this study, two-dimensional porous media with differently heterogeneous structures are reconstructed by utilizing the quartet structure generation set method. Fractal dimension and lacunarity are implemented to quantify the complex microstructure and analyze the relationships among these parameters. Under specific porosity, the fractal dimension increases with the reduction of lacunarity according to a power law relationship. Meanwhile, permeability has a perfect power law relationship with porosity under the same heterogeneity. The stronger heterogeneity increases the degree of pore aggregation, resulting in increased pore radius for fluid flow. For porous media with the same porosity, permeability has a significant positive power law relationship with lacunarity and a negative relationship with fractal dimension. The results demonstrate that fractal parameters are helpful to fully understand the influence of complex microstructure and chemical reactions on the macroscopic physical properties of porous media. • Two-dimensional porous media with differently complex and heterogeneous pore structures are reconstructed. • Fractal parameters are implemented to quantify the microstructure and analyze the relationships among these parameters. • The relationships between permeability and pore structural parameters are established. [ABSTRACT FROM AUTHOR]

A series of Tb3+ (or Bi3+) doped and Tb3+, Bi3+ co-doped CaAl 2 O 4 phosphors were successfully prepared by the conventional solid state reaction method. The properties of the as-prepared samples, including the crystal structure, morphology, composition and photoluminescence properties are characterized by the X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), energy dispersive spectrometer (EDS), high-angle annular dark field (HAADF) image and spectroscopy technology, etc. The diffraction patterns of the doped samples display the peaks corresponding to the CaAl 2 O 4 phase. The EDS and HAADF indicate that the Ca, Al, O, Tb and Bi elements are distributed uniformly in the Tb single-doped and the Tb, Bi co-doped CaAl 2 O 4 samples. In order to investigate the energy transfer from Bi3+ to Tb3+, the critical (or optimal) doped concentrations of Tb and Bi in CaAl 2 O 4 are obtained experimentally in sequential order. The critical doped concentrations (single-doped: 3 ​mol%Tb3+, and co-doped: 3 ​mol%Tb3+, 0.3 ​mol%Bi3+) for CaAl 2 O 4 hosts have been determined. A strong blue-green luminescence corresponding to 5D 4 →7F 5 transition of Tb3+ by near ultra-violet (367 ​nm) excitation and the obvious energy transfer from Bi3+ to Tb3+ in the co-doped CaAl 2 O 4 can be observed. The energy transfer mechanism has been discussed. The CIE coordinates and decay lifetimes for the typical samples have also been investigated. It is found that CaAl 2 O 4 : Tb3+, Bi3+ is a blue-green emitting phosphor and has higher efficiency for the operation with near ultra-violet excitation. The energy level scheme of Bi3+ and Tb3+ ions with optical transitions and energy transfer processes of Bi3+→Tb3+. Image 1 • Tb and/or Bi doped CaAl 2 O 4 is identified by XRD, SEM, HRTEM and spectroscopy. • The critical doping concentrations are determined. • The compositions and the lattice parameters are studied. • The bandgaps of the typical samples are obtained. • The energy transfer efficiency from Bi3+ to Tb3+ is 74.34%. [ABSTRACT FROM AUTHOR]

The successful pilot testing of depressurization production for natural gas hydrate reservoir was conducted at Shenhu Area in the South China Sea. However, pressure changes due to depressurization production cause shrinkage of creeping pore and throat space for fluid flow, ultimately resulting in permeability damage in this reservoir. To optimize gas recovery for natural gas hydrate reservoir, it is important to understand the substantial variations of the pore structure and physical properties under different pressure conditions. In this study, by integrating computed tomography imaging with water flow experiments on Clay-silt sediment sample, we analyze how pore scale structural parameters (such as average pore and throat radius, pore and throat median radius, maximum pore and throat radius, and fractal dimension) change under different axial stresses by using fractal geometry approach. It is found that there is a negative relationship between axial stress and structural parameters. Meanwhile, with the axial stress increases, the range of pore and throat radius distribution located on the right of center distribution decreases. On the basis of fractal geometry theory, a fractal model is then proposed to explain the effects of axial stress and creeping microstructure on permeability for natural gas hydrate reservoir. Results show that the model provides good match with experimental data when the axial stress is larger, while poor agreements with experimental results at low pressure. This study helps us understand fundamental mechanism for permeability changes during the depressurization of gas hydrate reservoir. • The creeping microstructural images of gas hydrate reservoir sediment are obtained by micro-CT. • The quantitive microstructure parameters under different axial stresss are simulated. • A creeping permeability fractal model is proposed and tested by experiments. [ABSTRACT FROM AUTHOR]

• Three fractal parameters (dimension, lacunarity and succolarity) were employed to characterize the microstructure of reservoir rocks. • Twelve 3D CT images of sandstone reservoir rocks with different permeabilities were used to estimate the three fractal parameters. • The fractal parameters, especially succolarity, identified differences in core micro-structure as related to differences in permeability. An explicit relationship between seepage properties and microscopic structure of porous media is being sought for the development of oil and gas resources. An effective method to accurately characterize and quantify the microscopic structure of porous media is a key issue. Fractal geometry can take advantage of several physically-based parameters to analyze microstructures of reservoir rocks. In this study, three fractal structural parameters, fractal dimension, lacunarity and succolarity, were employed to characterize scale-invariant complexity, heterogeneity, and anisotropy of rock microstructures, respectively. Twelve three-dimensional digital cores of sandstone reservoir rocks were used to evaluate permeability in terms of fractal dimension, lacunarity and succolarity. The parameters were utilized to quantitatively characterize differences in core micro-structure and predict their effects on permeability. Due to the confounding influence of porosity, the fractal dimension was not an accurate predictor of the variation in permeability on its own. Instead, the results reveal that lacunarity and succolarity were better able to predict differences in structure and permeability. Succolarity, in particular, showed an exponential relationship with permeability, yielding a coefficient of determination of 0.940. Using a combination of fractal structural parameters in the place of pore-size distribution, can provide a better explanation of the relationship between fluid flow, and the heterogeneous structure and anisotropic physical properties of reservoir rocks. [ABSTRACT FROM AUTHOR]

Shale contains abundant multicomponent nanopores with different wettability. Water flow in multicomponent nanoporous systems is still unclear due to the effects of mineral composition, complex pore-throat topology, and heterogeneous wettability. This work develops a contact angle-dependent numerical model for nanoconfined water flow considering heterogeneous wettability, slip effect, and effective viscosity. Water flow in single-component (i.e., clay, organic, inorganic) and multicomponent nanoporous media reconstructed utilizing image fusion techniques is systematically investigated. Results show that the enhancement factor increases exponentially, and the tortuosity increases with increasing contact angle. Water flow is inhibited under strongly hydrophilic conditions, with the enhancement factor linearly negatively correlated with specific surface area. Under hydrophobic conditions, the throat aspect ratio is inversely related to the enhancement factor, which is suppressed in quasi-circular pores. Water flow is restricted in clay pores and enhanced in organic pores due to the differences in pore-throat size and wettability. For the heterogeneous wetting system, the global flow is enhanced compared to no slip and homogeneous wetting conditions. Affected by clay and organic pores with different wettability, the velocity is non-uniformly enhanced, and the effect diminishes as water flows. This work provides a numerical perspective for water flow in heterogeneous wet nanoporous systems. • A contact angle-dependent numerical model for water flow is developed. • Negative slip is related to specific surface area in clay pores. • Throat aspect ratio and pore shape control enhancement effect. • Velocity is enhanced nonuniformly in organic matter under heterogeneous wet. [ABSTRACT FROM AUTHOR]

Peripheral serotonin levels are associated with cardiovascular disease risk. We previously found that serum serotonin levels are higher in hyperlipidemic mice than wild-type mice. Evidence also suggests that serotonin regulates biomineralization, in that serotonin treatment augments TNF-a-induced matrix calcification of aortic valve interstitial cells and that a selective inhibitor of peripheral serotonin, LP533401, rescues bone loss induced by ovariectomy in mice. Thus, in the present study, we examined the effects of LP533401 on both skeletal bone mineral density (BMD) and aortic calcification in both young and older hyperlipidemic mice susceptible to calcific atherosclerosis and bone loss. By serial in vivo microCT imaging, we assessed BMD and aortic calcification of Apoe −/− mice fed an atherogenic (high cholesterol) diet alone or mixed with LP533401. Results show that in the young mice, LP533401 blunted skeletal bone loss in lumbar vertebrae but not in femurs. LP533401 also blunted the initial development of aortic calcification but not its progression. Echocardiographic analysis showed that LP533401 blunted both hyperlipidemia-induced cardiac hypertrophy and left ventricular dysfunction. In the older mice, LP533401 increased the BMD of lumbar vertebrae but not of femurs. The aortic calcification progressed in both controls and LP533401-treated mice, but, at post-treatment, LP533401-treated mice had significantly less aortic calcification than the controls. These findings suggest that LP533401 mitigates adverse effects of hyperlipidemia on skeletal and vascular tissues in site- and stage-dependent manners. • Effects of serotonin inhibition were site- and disease-stage dependent. • LP533401 blunted diet-induced bone loss in lumbar vertebrae but not in femurs. • Development of aortic calcification, but not progression, was blunted by LP533401. • LP533401 mitigated hyperlipidemia-induced cardiac hypertrophy and LV dysfunction. [ABSTRACT FROM AUTHOR]

The sediment of the hydrate reservoir in the Shenhu Area is mainly clayey silt. Its characteristic small particles and poor cementation challenge the quantification of the reservoir permeability during gas production. An accurate description of the seepage mechanism of the clayey-silt reservoir is the basis, and also a difficulty, of effective development of gas in the South China Sea. In this study, four sets of water seepage experiments under different pressure gradients are carried out using the clayey-silt reservoir sediments, in which the fourth sample was subjected to computed tomographic (CT) scans. The experimental results shows that the clayey-silt reservoir has a compression of the pore structure and decreasing permeability with the increasing pressure gradient. CT images are used to show the reduction of pore spaces for fluid flow. When the pressure gradient is less than 3 MPa per meter, the pore structure of the reservoir has minor changes. When the pressure gradient is greater than this value, the pore structure of the reservoir will be quickly compressed. This leads to a rapid decrease in permeability, and the process of permeability reduction is irreversible. The decrease of permeability can be predicted directly by establishing a power law model with the change of porosity. Our experimental results preliminarily reveal the dynamic evolution law of pore structure and permeability of clayey-silt reservoir in the process of gas hydrate exploitation via depressurization. The permeability evolution law at various pressure gradients provides a scientific and reasonable basis of a productivity control system for clayey-silt gas hydrate in depressurized gas production. [ABSTRACT FROM AUTHOR]

• Nanocale crack-hole interactions in chiral GNRs are investigated by MD simulations and FE analysis. • Carbon-carbon bond in the FE method is modeled as a nonlinear Timoshenko beam based on the REBO potential. • Shielding effects on the crack tip stress field are dominated by the angle, hole-to-crack tip spacing and chirality of the GNRs. Nanoscale defects (such as cracks, holes) often occur in graphene nanoribbons (GNRs). However, it is still a big challenge to accurately predict crack-hole interactions in them. In this study, the nanocale crack-hole interactions in chiral GNRs are investigated under mode-I loading using molecular dynamics (MD) simulations and finite element (FE) analysis. The carbon-carbon (C C) bond in the FE method is modeled as a nonlinear Timoshenko beam based on the full-atom Reactive Empirical Bond-Order interatomic potential of second generation (REBO potential) for the first time. The present MD and FE results show that the shielding effects on the crack tip stress field are dominated by the angle is θ , the hole-to-crack tip spacing r and the chirality of the GNRs. Checking against the linear-elastic fracture mechanics (LEFM) predictions of some crack-hole configurations shows that the present FE method and MD simulations have high accuracy. This study should be of great help for understanding nanoscale crack-hole interactions in GNRs and providing physical insights into the origins of defect engineering of GNRs. [ABSTRACT FROM AUTHOR]

The complicated flow behaviors of multiphase fluids in shale reservoirs are significantly influenced by fluid-fluid and fluid-rock interactions due to the non-negligible intermolecular forces at the nanoscale, which is crucial for the effective development and efficient extraction of shale oil. The complexity of multiphase fluid distribution and flow behaviors in shale reservoirs is further increased by low porosity, low permeability, poor connectivity, high inhomogeneity, and multi-component minerals, making the development process more challenging. Molecular dynamics simulation is widely to precisely capture the intermolecular forces and effectively explain the complex distribution and flow behaviors of these fluids under fluid-fluid and fluid-rock interaction forces. In this review, the characteristics of mineral composition, pore structure, porosity, permeability, and fluid types are first elaborated to illustrate the particularity of shale reservoirs and fluids compared to conventional scale reservoirs. The results show that shale minerals are composed of inorganic and organic matter with extremely low porosity and permeability, and nanoscale pore size, in which the complicated oil-water-CO 2 multiphase fluid types are caused by the primary underground water, fracturing water and injected CO 2. The research progress of molecular simulation on the fluid-fluid and fluid-rock interaction mechanisms and on multiphase shale fluids flow behaviors are then reviewed in detail. The strong intermolecular interaction forces can result in the different occurrence states of fluids, the fluid-fluid interfacial slip, the fluid-rock boundary slip and heterogeneous fluid viscosity/density, significantly exacerbating the complexity of fluids flow. Meanwhile, the injected CO 2 in the formation becomes a supercritical state with high diffusivity and strong solubility, and causes oil expansion, density and viscosity reduction, interfacial tension reduction, wettability alteration and molecular diffusion, which effectively replaces adsorbed hydrocarbon components by competitive adsorption behaviors, and promotes oil flow. The challenges and outlook of molecular simulation research and upscaling applications are finally discussed. This review aims to provide a microscopic understanding of the distribution characteristics and flow behaviors of multiphase shale fluids in nanoconfined space for both unconventional oil and gas researchers and industry professionals. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a complex disorder with an unknown cause. However, the dysbiosis of the gut microbiome has been found to play a role in IBD etiology, including exacerbated immune responses and defective intestinal barrier integrity. The gut microbiome can also be a potential biomarker for several diseases, including IBD. Currently, conventional treatments targeting pro-inflammatory cytokines and pathways in IBD-associated dysbiosis do not yield effective results. Other therapies that directly target the dysbiotic microbiome for effective outcomes are emerging. We review the role of the gut microbiome in health and IBD and its potential as a diagnostic, prognostic, and therapeutic target for IBD. This review also explores emerging therapeutic advancements that target gut microbiome-associated alterations in IBD, such as nanoparticle or encapsulation delivery, fecal microbiota transplantation, nutritional therapies, microbiome/probiotic engineering, phage therapy, mesenchymal stem cells (MSCs), gut proteins, and herbal formulas. [Display omitted] • The gut microbiota plays a significant role in health and the development of inflammatory bowel disease. • The gut microbiota is a potential biomarker for diagnosing, prognosing, and predicting therapy outcomes in IBD. • Therapies have been shown to regulate the dysbiotic microbiome environment in IBD to promote a state of eubiosis. [ABSTRACT FROM AUTHOR]

The corrosion behavior of an Al 0.1 CoCrFeNi HEA in high temperature CO 2 at 850 °C for different exposure periods was investigated using different characterization methods. Weight gain increased with extended exposure periods, yet it remained lower than most conventional alloys. A double-layer oxide film consisting of Cr 2 O 3 and Al 2 O 3 formed after 100 and 500 h of exposure, while a single layer of Cr 2 O 3 developed after 1000 h of exposure. CoCrFeNi particles with an FCC structure were embedded in the oxide films irrespective of the exposure periods. Moreover, a transition zone containing numerous striped-like Al 2 O 3 oxides along the grain boundaries was developed underneath the oxide films. • Corrosion behavior of Al 0.1 CoCrFeNi HEA in high temperature CO 2 environment was investigated. • A Cr 2 O 3 and Al 2 O 3 layer formed after 100 and 500 h of exposure, while single Cr 2 O 3 layer developed after 1000 h. • CoCrFeNi particles with an FCC structure were embedded in the oxide films irrespective of the exposure periods. • A transition zone containing striped Al 2 O 3 along the grain boundaries formed underneath the Cr 2 O 3 layer. [ABSTRACT FROM AUTHOR]

• A PI-Unet-BGK network is established based on the LBM-BGK. • The PI-Unet-BGK network is used to simulation the steady-state and dynamic flow. • The average error of predicted dynamic flow field are mostly less than 10−3. The simulation of flow in porous media holds significant importance in investigating various phenomena, but current simulation methods are time-consuming. Recently developed physics-informed neural network employs physical constraints during training, enabling the learning of a more generalized model with limited data samples. This substantially reduces the learning cost and introduces a novel approach to solving flow calculations in porous media. To simulate steady-state and dynamic flow processes of single-phase flow in complex porous media, a physical-informed Unet network (PI-Unet-BGK) is established based on the lattice Boltzmann method with the Bhatnagar-Gross-Krook (BGK) collision model. This research demonstrates that the PI-Unet-BGK network outperforms the conventional Unet network in predicting steady-state flow fields for multiple Berea sandstone slices. Its coefficient of determination is 0.2788, it has improved by 0.06 compared to the Unet network. The relative error of permeability of carbonate rock and shale slices are 64% and 117%. Regarding dynamic single-phase flow simulation, the PI-Unet-BGK network exhibits favorable performance in simulating the flow process within Berea sandstone slices. However, it has some errors at initial stage. When test on a carbonate rock and shale slices, it can only simulate the trend of fluid transport, our model exhibits limited transfer learning ability. [ABSTRACT FROM AUTHOR]

Cardiovascular disease and osteoporosis, major causes of morbidity and mortality, are associated with hyperlipidemia. Recent studies show that empagliflozin (EMPA), an inhibitor of sodium-glucose cotransporter-2 (SGLT2), improves cardiovascular health. In preclinical animal studies, EMPA mitigates vascular calcification in the males but its effects in the females are not known. Thus, we used female mice to test the effects of EMPA on calcification in the artery wall, cardiac function, and skeletal bone. By serial in vivo microCT imaging, we followed the progression of aortic calcification and bone mineral density in young and older female Apoe −/− mice fed a high-fat diet with or without EMPA. The two different age groups were used to compare early vs. advanced stages of aortic calcification. Results show that EMPA treatment increased urine glucose levels. Aortic calcium content increased in both the controls and the EMPA-treated mice, and EMPA did not affect progression of aortic calcium content in both young and older mice. However, 3-D segmentation analysis of aortic calcium deposits on microCT images revealed that EMPA-treated mice had significantly less surface area and volume of calcified deposits as well as fewer numbers of deposits than the control mice. To test for direct effects on vascular cell calcification, we treated murine aortic smooth muscle cells with EMPA, and results showed a slight inhibition of alkaline phosphatase activity and inflammatory matrix calcification. As for skeletal bone, EMPA-treated mice had significantly lower BMD than the controls in both the lumbar vertebrae and femoral bones in both young and older mice. The findings suggest that, in hyperlipidemic female mice, unlike males, SGLT2 inhibition with empagliflozin does not mitigate progression of aortic calcification and may even lower skeletal bone density. [Display omitted] [ABSTRACT FROM AUTHOR]

Though fullerene has been regarded as an effective radical scavenger, the hydrophobicity strongly limits its application in biological fields. Herein, we proposed a simple photoreduction method in preparing a highly water-soluble nanocomposite consisting of ultrasmall copper nanoparticles (CuNPs) and hydroxylated fullerene (fullerenol), which showed excellent radical scavenging performance compared with traditional antioxidants. The superb antioxidative behavior was believed to be due to the synergetic effect induced by the stable decoration of CuNPs onto the surface of fullerenol, while the low metal loading level would decrease the potential toxicity of the prepared composite. Our work will offer an alternative choice for efficient antioxidative agents with more biosafety. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis (PF) is a pathological process of irreversible scarring of lung tissues, with limited treatment means. Sceptridium ternatum (Thunb.) Lyon (STE) is a traditional Chinese herbal medicine that has a traditional use in relieving cough and asthma, resolving phlegm, clearing heat, and detoxicating in China. However, its role in PF has not been reported. This study aims to investigate the protective role of STE in PF and the underlying mechanisms. Sprague-Dawley (SD) rats were divided into control group, PF model group, positive drug (pirfenidone) group and STE group. After 28 days of STE administration in bleomycin (BLM)-induced PF rats, living Nuclear Magnetic Resonance Imaging (NMRI) was used to observe the structural changes of lung tissues. H&E and Masson's trichrome staining were used to observe PF-associated pathological alteration, and immunohistochemistry (IHC) staining, western blotting, and qRT-PCR were used to detect the expression of PF-related marker proteins in the lung tissues. ELISA was used to detect PF-associated biochemical criteria in the lung tissue homogenates. The proteomics technology was used to screen the different proteins. Co-immunoprecipitation, western blotting, and IHC staining were used to confirm the underlying targets of STE as well as its downstream signaling. UPLC-Triple-TOF/MS assay was used to explore the effective components in the alcohol extracts of STE. Autodock vina was used to detect the potential binding between the above effective components and SETDB1. STE prevented PF by inhibiting the activation of lung fibroblasts and ECM deposition in BLM-induced PF rats. Mechanism analyses demonstrated that STE could inhibit the up-regulation of SETDB1 induced by BLM and TGF-β1, which further blocked the binding of SETDB1 and STAT3 as well as the phosphorylation of STAT3, ultimately preventing the activation and proliferation of lung fibroblasts. STE played a preventive role in PF by targeting the SETBD1/STAT3/p-STAT3 pathway, which may be a potential therapeutic agent for PF. The alcohol extracts of Sceptridium ternatum (Thunb.) Lyon exert an anti-pulmonary fibrosis effect by inhibiting the up-regulation of SETDB1 induced by BLM and TGF-β1, which further blocks the binding of SETDB1 and STAT3 and the following phosphorylation of STAT3, finally preventing the activation and proliferation of lung fibroblasts and the accumulation of excessive extracellular matrix. [Display omitted] • The alcohol extracts of STE could prevent pulmonary fibrosis through inhibiting the accumulation of extracellular matrix. • SETDB1 was selected to be an effective therapeutic target of STE on treating pulmonary fibrosis. • SETDB1 knockdown could prevent pulmonary fibrosis through blocking the activation of STAT3/p-STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

Cardiovascular disease risk is associated with coronary artery calcification and is mitigated by regular exercise. Paradoxically, elite endurance athletes, who have low risk, are likely to have more coronary calcification , raising questions about the optimal level of activity. Female hyperlipidemic (Apoe −/− ) mice with baseline aortic calcification were subjected to high-speed (18.5 m/min), low-speed (12.5 m/min), or no treadmill exercise for 9 weeks. 18F–NaF microPET/CT images were acquired at weeks 0 and 9, and echocardiography was performed at week 9. In controls, aortic calcium content and density increased significantly. Exercise regimens did not alter the time-dependent increase in content, but the increase in mean density was blunted. Interestingly, the low-speed regimen significantly reduced 18F–NaF uptake, a marker of surface area. Left ventricular (LV) systolic function was lower while LV diameter was greater in the low-speed group compared with controls or the high-speed group. In the low-speed group, vertebral bone density by CT decreased significantly, contrary to expectations. Male hyperlipidemic (Apoe −/− ) mice were fed a Western diet and also subjected to low-speed or no exercise followed by imaging at weeks 0 and 9. In males, exercise also did not alter the time-dependent increase in aortic calcification. Exercise did not affect 18F–NaF uptake or bone mineral density, but it blunted the diet-induced LV hypertrophy seen in controls. These results suggest that, in mice, exercise has differential effects on aortic calcification, cardiac function, and skeletal bone mineral density. [Display omitted] • Aortic calcium content by microCT increased significantly over the 9-week period, in both control and treadmill groups. • Progression of aortic calcification in the activity groups was not significantly different from that of the control groups. • In females, a low-speed regimen reduced aortic mineral surface area by microPET and vertebral BMD as measured by microCT. • In males, a low-speed regimen blunted the Western diet-induced left ventricular hypertrophy observed in controls. [ABSTRACT FROM AUTHOR]

The effect of shear displacement on the directivity of permeability in fractures is studied in this paper. The studied fracture surface has 3D self-affine fractal characteristics that are created using the modified successive random addition (SRA) method. Fluid flow through the fracture is simulated using the COMSOL Multiphysics code based on the finite element method (FEM) by changing the angle between the shear direction and macroscopic flow direction. The evolutions of the aperture distribution and flow paths with changes in shear displacement are investigated, and the change in the equivalent permeability is evaluated. The results show that the mean aperture and its deviation for rough fractures increase as the shear displacement increases, and this change is accompanied by an increase in void spaces and decreasing contact areas between the upper and lower fracture surfaces. The flow paths become more tortuous, and the channeling flow effect occurs during the shear process. The equivalent permeability of the fractures varies as the inclination between the shear direction and macroscopic flow direction changes. The permeability with the largest magnitude exists in the direction perpendicular to the shear direction, and the permeability with the smallest magnitude exists in the direction parallel to the shear direction. The equivalent permeability of the fractures at other inclinations varies between the smallest and greatest values. Notably, larger inclinations correspond to higher permeability magnitudes. The ratio of the directional permeability to the permeability in the direction parallel to the shear direction varies between 1.03 and 2.71. This ratio tends to decrease as the shear displacement and JRC increase, which indicates that the directivity of the permeability is more obvious for fractures with smaller JRCs and smaller shear displacement. [ABSTRACT FROM AUTHOR]

The effect of model size on fluid flow through fractal rough fractures under shearing is investigated using a numerical simulation method. The shear behavior of rough fractures with self-affine properties was described using the analytical model, and the aperture fields with sizes varying from 25 to 200mm were extracted under shear displacements up to 20mm. Fluid flow through fractures in the directions both parallel and perpendicular to the shear directions was simulated by solving the Reynolds equation using a finite element code. The results show that fluid flow tends to converge into a few main flow channels as shear displacement increases, while the shapes of flow channels change significantly as the fracture size increases. As the model size increases, the permeability in the directions both parallel and perpendicular to the shear direction changes significantly first and then tends to move to a stable state. The size effects on the permeability in the direction parallel to the shear direction are more obvious than that in the direction perpendicular to the shear direction, due to the formation of contact ridges and connected channels perpendicular to the shear direction. The variances of the ratio between permeability in both directions become smaller as the model size increases and then this ratio tends to maintain constant after a certain size, with the value mainly ranging from 1.0 to 3.0. [ABSTRACT FROM AUTHOR]

Uniform sets of mono-crystalline nanoparticles ranging from 6 nm to over 100 nm were prepared for the MgO, Co3O4, and Fe3O4 oxide systems. The nanoparticles were characterized by transmission electron microscopy ( TEM) and x-ray diffraction ( XRD). A careful analysis shows increased lattice parameter for smaller nanoparticles of each oxide system: 0.47% expansion from bulk for 7 nm MgO crystallites, 0.15% expansion from bulk for 9 nm Co3O4 crystallites, and 0.13% expansion from bulk for 6 nm Fe3O4 crystallites. The compressive surface stresses and expansion energies against hydrostatic pressure for each oxide system were calculated, respectively, to be 4.13 N/m and 1.8 meV/formula unit for MgO, 3.09 N/m and 0.87 meV/formula unit for Co3O4, and 1.26 N/m and 0.67 meV/formula unit for Fe3O4. The fundamental understanding of oxide nanoparticle mechanics as presented here will facilitate integration of these materials into technological applications in a rationally designed manner. [ABSTRACT FROM AUTHOR]

Compared to their parent materials, oxygen vacancy (VO)–ordered phases of complex oxides exhibit distinct physical properties and show great potential in multifunctional devices. With the expected unique behaviors, however, most of the VO‐ordered oxide films are extremely difficult to synthesize due to their thermodynamic instabilities. Herein, using LaCoOx as an example, the synthesis of large‐scale monophased VO‐ordered LaCoO2.67 and LaCoO2.5 films is realized by annealing as‐grown perovskite LaCoO3 films in vacuum with a special heating method. Their macroscopic properties, including the magnetic and electric transport and optical properties, are measured. It is demonstrated that the functionalities of LaCoOx films can be manipulated by tuning the concentration and ordering of the VO. The method in this work can be applied to fabricate a wide range of VO‐ordered oxide films. [ABSTRACT FROM AUTHOR]

In this paper, the nuclear magnetic resonance (NMR) technique is applied to exploring the spontaneous imbibition mechanism in tight sandstones under all face open (AFO) boundary conditions, which will benefit a better understanding of spontaneous imbibition during the development of oil & gas in tight formations. The advantages of nuclear magnetic resonance imaging (NMRI) and NMR T2 are used to define the distribution of remaining oil, evaluate the effect of micro structures on imbibition and predict imbibition recovery. NMR T2 results show that pore size distributions around two peaks are not only the main oil distributions under saturated condition but also fall within the main imbibition distributions range. Spontaneous imbibition mainly occurs in the first 6 h and then slows down and even ceases. The oil signals in tiny pores stabilize during the early stage of imbibition while the oil signal in large pores keeps fluctuating during the late stage of imbibition. NMRI results demonstrate that spontaneous imbibition is a replacement process starting slowly from the boundaries to the center under AFO and ending with oil-water mixing. Furthermore, the wetting phase can invade the whole core in the first 6 h, which is identical with the main period of imbibition occurring according to NMR T2 results. Factors influencing the history of oil distribution and saturation differ at different periods, while it is dominated by capillary imbibition at the early stage and allocated by diffusion at later time. Two imbibition recovery curves calculated by NMRI and NMR T2 are basically consistent, while there still exists some deviations between them as a result of the resolutions of NMRI and NMR T2. In addition, the heterogeneity of pore size distributions in the two samples aggravates this discrepancy. The work in this paper should prove of great help to better understand the process of the spontaneous imbibition, not only at the macroscopic level but also at the microscopic level, which is significant for oil/gas recovery in tight formations. [ABSTRACT FROM AUTHOR]