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Understanding fluid flows in heterogeneous porous media is fundamental to applied geosciences. The wide connectivity variations in the natural aquifer or oil reservoirs make the equivalent permeability have strong spatial variations. When performing the simulations for subsurface flows, the permeabilities may have strong discontinuities across the interfaces between different grid cells. Utilizing the traditional numerical schemes to simulate flows in strong heterogeneous media, the refinement ratio for the grid cell needs to increase dramatically to get an accurate result. Recently, we proposed a finite analytic numerical scheme to solve the two-dimensional fluid flows in heterogeneous porous media. With only 2 × 2 or 3 × 3 subdivisions, this scheme can provide rather accurate solutions. In this paper, we develop the finite analytic numerical method for solving the three-dimensional fluid flows in heterogeneous porous media. For the rectangular grid system, it is generally proposed that the pressure gradient in a plane normal to the edge joining different permeability regions will tend to infinite as approaching the edge according to a typical power-law solution and the tangential derivate of the pressure along the edge must be of limited value due to the pressure continuity. Consequently, the three-dimensional flow will reduce to the two-dimensional one in the neighborhood around each edge. Such quasi-two-dimensional behavior is then applied to construct a finite analytic numerical scheme. Numerical examples show that the proposed scheme can provide rather accurate solutions with only 2 × 2 × 2 or 3 × 3 × 3 subdivisions and the convergent speed is independent of the permeability heterogeneity. Due to its high calculation efficiency, the proposed scheme is utilized to test the well known LLM (Landau, Lifshitz and Matheron) conjecture, which provides k eq / k G = exp ⁡ ( 1 6 σ ln ⁡ k 2 ) for the isotropic log-normal porous medium. The numerical results do not support this conjecture for large σ ln ⁡ k , but strongly suggest the linear relation k eq / k G = 1 + 1 6 σ ln ⁡ k 2 . [ABSTRACT FROM AUTHOR]

The vibrational spectroscopy of monohydrated dihydrogen phosphate anions, H2PO4−(H2O), is studied in the O–H stretching (2700–3900 cm−1) and the fingerprint regions (600–1800 cm−1). Assignment of the experimental infrared multiple photon photodissociation spectra based on the predicted harmonic spectra of energetically low-lying 0 K structures is not conclusive. Ab initio molecular dynamics simulations reveal that the water molecule undergoes large amplitude motion, even at low internal temperatures, and that the dipole time correlation function qualitatively captures the anharmonic effects of the low-barrier isomerization reaction on the infrared intensities. [ABSTRACT FROM AUTHOR]

This paper presented a new rotor hybrid topologies structure of both the permanent magnet (PM) motors. Surface mounted, built-in and hybrid permanent magnet motor topology model was established using the finite element method to calculate the static magnetic field three structures of the motor. Comparative analysis of their contour distribution of the pole from the amplitude distribution within the air gap flux density in one pole zone was done. EMF distribution in permanent magnet motor with new structure was more close to the sine based on simulation and analysis of EMF. The torque and stator loss without load were calculated. [ABSTRACT FROM AUTHOR]

In this study, the effects of three surfactants, i.e. the anionic biosurfactant dirhamnolipid (diRL), the cationic surfactant hexadecyltrimethyl ammonium bromide (CTAB), and the anionic surfactant sodium dodecyl sulfate (SDS), on the removal of phenol catalyzed by laccase were studied first. CTAB and SDS were detrimental, while diRL improved phenol removal and was selected for detailed research. The biosurfactant increased the activity of laccase and the removal of phenol with the increase of diRL concentrations from 10.6 to 318 μM. DiRL at 318 μM improved the removal when the initial concentrations of phenol were from 50 to 400 mg/l. In particular, the removal of phenol with 318 μM diRL was 4.3-6.4 folds that of the controls within 24 h when the initial concentration of phenol was 400 mg/l. The presence of diRL at 318 μM also caused the complete removal (above 98%) of phenol at concentrations from 50 to 400 mg/l after 24 h. The enhancement of phenol removal was over a wide range of pH and temperatures, and the highest removal efficiency was obtained at pH 6.0 and 50°C. The results suggest that diRL had potential application in the enhancement of phenols removal catalyzed by laccase in water treatment or remediation. [ABSTRACT FROM AUTHOR]

Joint often have a significant effect on the dynamical behavior of assembled mechanical structures. The dynamical characteristic of joint is complex, and many researches focus on the identification of it. A new method to identify the joint pa- rameters is proposed based on the incomplete input information in this paper. Firstly, the unmeasured frequency response functions (FRFs) are identified by experimental and finite element method, and completely FRFs are constructed. Then, the dynamic parameters of joint are identified by iterative algorithms based on the completely FRFs. The loss function is estab- lished in this paper, which can be identified the parameters of joint by minimizing the loss function. Since this method does not need modal parameters, it can be used effectively to identify joint characteristics when the system has heavy damping or closely coupled modes. Furthermore, the proposed method makes use of only a few FRFs which are not necessarily related to the joint but related to easily accessible points. Thus, this method can be applied to real structures usually having rotational and inaccessible degree of freedoms. Finally, the validity and feasibility of the proposed method are demonatrated an example. The results show that joint structural parameters can be identified accurately. [ABSTRACT FROM AUTHOR]

The icosahedral Al−13is a “magic” cluster with remarkable stability due to its high symmetry and closed valence shells. Its reactivity has provided a molecular model for understanding oxidation and dissolution processes in bulk metals. By first principles calculations, we demonstrated the importance of dynamic factors in the Al−13+ HX reactions, with HX being either HCl or HI. There was a barrier to the dissociative adsorption of HX on the surface of an Al−13cluster, which involved charge transfer from Al−13. Furthermore, the H atom could be bonded to the cluster in multiple ways, similar to the top, bridge and hollow adsorption sites on Al(111) surface. With a large amount of energy (∼40 kcal mol−1) deposited during the formation of Al13HX−, the H atom could easily migrate among these sites, similar to the diffusion of hydrogen on metal surfaces. These factors were therefore important considerations in the formation and dissociation of Al13HX−, and more generally in reactions involving other metal clusters. [ABSTRACT FROM AUTHOR]

Objective: To analyze the proteomic characteristics of Gan ([Chinese text])-stagnancy syndrome (GSS) by seeking the differential protein in blood and tissues of GSS model rats. Methods: GSS model rats were established by chronic restraint stress, keeping rats in restrain chamber for 6 h every day for 21 successive days. Their blood and liver samples were collected at the end of experiment for differential protein detection with methods of isoelectrofocusing and polyacrylamide SDS-PAGE, silver staining, and scanning. The gel images were analyzed with Imagemaster 2D Elite software, and the excavated differential protein spots were identified with matrix assistant laser resolving TOF mass spectrometry, Western blot, ELISA, and RT-PCR, respectively. Results: A method for isolating the protein in blood serum and tissues by two-dimensional gel electrophoresis was established and optimized. Six serum proteins and three liver proteins that differentially expressed were identified. The down-regulated differential proteins in serum of GSS model rats were serum albumin precursor, beta 1 globin, antibody against muscle acetylcholine receptor, Ig lambda-2 C region, and transthyretin (TTR), and those in liver tissue were aryl sulfotransferase, enoyl-CoA hydratase, and TTR. TTR down-regulation was found in both serum and liver. Preliminary biological information analysis showed that these differential proteins involved in immune, neuroendocrine, nutrition, and substance metabolism. Conclusion: Proteomic analysis of differential proteins showed that TTR, aryl sulfotransferase, and enoyl-CoA hydratase expressions are downregulated in the GSS model rats, suggesting that the susceptibility of cancer could be enhanced by chronic stress. [ABSTRACT FROM AUTHOR]

This study contributes to construct the mathematical model of hybrid dynamic economic emission dispatch (HDEED) considering renewable energy generation and propose a novel solving approach based on enhanced moth-flame optimization algorithm. Renewable energy power generation technology has an important impact on reducing pollutant emissions and promoting sustainable development. Therefore, this study aims to investigate the HDEED problem in consideration of renewable energy generation and improve the economic and environmental benefits of the power system. First, a moth-flame optimization algorithm based on position disturbance updating strategy (MFO_PDU) was proposed aiming at the non-convex, non-linear and high-dimensional characteristics of HDEED problem. Second, the mathematical model of HDEED on the basis of Wind-Solar-Thermal integrated energy was constructed, while taking into account the valve point effect, equality constraints and inequality constraints. Finally, three cases including test systems of different scales were formulated and employed to verify the proposed approach, and the compromise solution was determined through membership function. The results revealed that the fuel cost obtained by the MFO_PDU algorithm was 11.31%, 4.01% and 5.27% smaller than those of HHO, TSA and MFO algorithms for small-scale test system. Accordingly, the research outcomes contribute in reducing the fuel cost and pollutant emissions of power generation system, and further improving the utilization and penetration rate of renewable energy. [Display omitted] • A hybrid dynamic economic emission dispatch model is formulated. • A novel MFO_PDU-based optimization strategy is proposed to solve HDEED problem. • The MFO_PDU-based approach can solve the HDEED problem efficiently. • The environmental and economic benefits of the power system are improved. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, we improve the traditional adaptive mesh refinement (AMR) by combining it with the finite analytical method (FAM) to solve the multiphase flow in heterogeneous porous media numerically. The FAM can provide rather accurate internodal transmissibility, and it is employed to improve the accuracy of coarsening and refining processes in AMR. The high performance of the proposed AMR‐FAM is indicated through numerical tests for solving the two‐phase flow in 2D heterogeneous media. The numerical simulation results indicate that the proposed AMR‐FAM is more accurate than the traditional AMR‐FAM. Compared with the simulation in the original fine grids, the proposed AMR‐FAM can provide nearly the same results. Moreover, the computational cost in the AMR grids is only approximately one‐third of the cost in the original fine grids according to our numerical tests. [ABSTRACT FROM AUTHOR]

COVID-19 may induce a state of hypercoagulability, particularly in critically ill patients, for reasons that remain unknown. Numerous studies have identified the presence of antiphospholipid antibodies in patients with COVID-19; however, the definitive diagnosis of antiphospholipid syndrome continues to pose challenges. Here, we present the case of a patient infected with SARS-CoV-2 who developed life-threatening severe thrombocytopenia, profound anaemia, acute pulmonary hypertension, right ventricular failure, and renal insufficiency. Laboratory investigations revealed significantly elevated levels of antiphospholipid antibodies. We conducted a one-year follow-up study with blood sampling performed every 12 weeks. The patient exhibited persistent high titres of antiphospholipid antibodies and ongoing renal dysfunction necessitating daily oral warfarin antithrombotic therapy. Antiphospholipid syndrome is a complex clinical condition that poses challenges for clinicians, particularly in critically ill patients, and is often associated with delayed and inaccurate diagnosis and treatment. Therefore, we extensively reviewed the literature and international guidelines to conduct a comprehensive analysis of the aetiology, pathogenesis, and treatment strategies of APS. We hope this work will provide a valuable reference for health care professionals. [ABSTRACT FROM AUTHOR]

This study proposes improved tunicate swarm algorithm (ITSA) for solving and optimizing the dynamic economic emission dispatch (DEED) problem. The DEED optimization target is to reduce the fuel cost and pollutant emission of the power system. In addition, DEED is a complex optimization problem and contains multiple optimization goals. To strengthen the ability of the ITSA algorithm for solving DEED, the tent mapping is employed to generate initial population for improving the directionality in the optimization process. Meanwhile, the gray wolf optimizer is used to generate the global search vector for improving global exploration ability, and the Levy flight is introduced to expand the search range. Three test systems containing 5, 10 and 15 generator units are employed to verify the solving performance of ITSA. The test results show that the ITSA algorithm can provide a competitive scheduling plan for test systems containing different units. ITSA proposed algorithm gives the optimal economic and environmental dynamic dispatch scheme for achieving more precise dispatch strategy. [Display omitted] • This study proposes ITSA to solve the dynamic economic emission dispatch problem in power system. • The Tent mapping is used to generate initial population for improving the ITSA directionality in the optimization process. • The gray wolf optimizer is used to generate the global search vector for improving global ITSA optimization ability. • The Levy flight is introduced to expand the ITSA search range. • The results show that the ITSA has better optimization ability and stability. [ABSTRACT FROM AUTHOR]

A correction to this paper has been published: https://doi.org/10.1007/s11051-021-05230-4 [ABSTRACT FROM AUTHOR]

Microbial oligosaccharides have been regarded as one of the most appealing natural products attributable to their potent and selective bioactivities, such as antimicrobial activity, inhibition of α-glucosidases and lipase, interference of cellular recognition and signal transduction, and disruption of cell wall biosynthesis. Accordingly, a handful of bioactive oligosaccharides have been developed for the treatment of bacterial infections and type II diabetes mellitus. Given that naturally occurring oligosaccharides have increasingly gained recognition in recent years, a comprehensive review is needed. The current review highlights the chemical structures, biological activities and divergent biosynthetic origins of three subgroups of oligomers including the acarviosine-containing oligosaccharides, saccharomicins, and orthosomycins. [ABSTRACT FROM AUTHOR]

Photovoltaic power generation is greatly affected by weather conditions while the photovoltaic power has a certain negative impact on the power grid. The power sector takes certain measures to abandon photovoltaic power generation, thus limiting the development of clean energy power generation. This study is to propose an accurate short-term photovoltaic power prediction method. A new short-term photovoltaic power output prediction model is proposed Based on extreme learning machine and intelligent optimizer. Firstly, the input of the model is determined by correlation coefficient method. Then the chicken swarm optimizer is improved to strengthen the convergence. Secondly, the improved chicken swarm optimizer is used to optimize the weights and the extreme learning machine thresholds to improve the prediction effect. Finally, the improved chicken swarm optimizer extreme learning machine model is used to predict the photovoltaic power under different weather conditions. The testing results show that the average mean absolute percentage error and root mean square error of improved chicken swarm optimizer - extreme learning machine model are 5.54% and 3.08%. The proposed method is of great significance for the economic dispatch of power systems and the development of clean energy. • The ICSO-ELM model is firstly proposed to predict the short-term photovoltaic power. • The proposed model is used to predict photovoltaic power under weather conditions. • ICSO optimizer's convergence ability is strengthened. • The PV power curtailment rate is reduced and the development of clean energy can be promoted. [ABSTRACT FROM AUTHOR]

Background. Secreted protein acidic and rich in cysteine-like 1 (SPARCL1) plays an important role in tumor pathogenesis. We aim to evaluate the clinical significance and potential biological roles of SPARCL1 in colorectal cancer (CRC). Methods. Datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were downloaded to evaluate the expression levels of SPARCL1 in CRC. Receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic value of SPARCL1. Then, comprehensive database search was conducted for published clinical studies to explore clinical significance of SPARCL1. In addition, coexpression genes of SPARCL1 were identified through the cBioPortal database and enrichment analysis of SPARCL1 and its coexpression genes were performed by the "clusterProfiler" R package. Finally, the correlations between SPARCL1 and tumor microenvironment scores, tumor-infiltrating immune cells in CRC were determined by "ESTIMATE" and "GSVA" R packages. Results. SPARCL1 was significantly downregulated in CRC tissues, and SPARCL1 showed high accuracy for diagnosis of primary CRC in both GEO and TCGA datasets. Pooled results from published clinical studies showed SPARCL1 expression was associated with differentiation (OR = 1.89 , 95% CI: 1.38-2.59), tumor stage (OR = 0.47 , 95% CI: 0.29-0.77), distant metastasis (OR = 0.53 , 95% CI: 0.33-0.84), and overall survival (HR = 0.56 , 95% CI: 0.43-0.74). SPARCL1 and its top 300 coexpression genes were involved in several KEGG pathways, such as focal adhesion, cell adhesion molecules, PI3K-Akt signaling pathway, cGMP-PKG signaling pathway, and ECM-receptor interaction. Besides, the SPARCL1 expression was significantly correlated with stromal score, immune score, ESTIMATE score, and diverse immune cells. Conclusion. SPARCL1 significantly correlated with clinicopathological features and tumor microenvironment in CRC. [ABSTRACT FROM AUTHOR]

In the last years, subspace‐based multi‐view face recognition has attracted increasing attention and many related methods have been proposed. However, the most existing methods ignore the specific local structure of different views. This drawback can cause these methods' discriminating ability to degrade when many noisy samples exist in data. To tackle this problem, a multi‐view low‐rank representation method is proposed, which exploits both intrinsic relationships and specific local structures of different views simultaneously. It is achieved by hierarchical Bayesian methods that constrain the low‐rank representation of each view so that it matches a linear combination of an intrinsic representation matrix and a specific representation matrix to obtain common and specific characteristics of different views. The intrinsic representation matrix holds the consensus information between views, and the specific representation matrices indicate the diversity among views. Furthermore, the model injects a clustering structure into the low‐rank representation. This approach allows for adaptive adjustment of the clustering structure while pursuing the optimization of the low‐rank representation. Hence, the model can well capture both the relationship between data and the clustering structure explicitly. Extensive experiments on several datasets demonstrated the effectiveness of the proposed method compared to similar state‐of‐the‐art methods in classification and clustering. [ABSTRACT FROM AUTHOR]

• The presence of an anion is considered in modeling oxygen reduction in H 2 O/Pt(1 1 1) interface. • Free energy surfaces explored by ab initio Molecular Dynamics/thermodynamic integration. • Comparisons in ORR between the HBr, HClO 4 , and H models explored. • New insights into the reactivity of adsorbed O*. • New insights into the coupling of OOH formation and O 2 dissociation. By ab initio molecular dynamics simulations, we examined the variation in the oxygen reduction reaction pathways on Pt(1 1 1) in the presence of H, HBr or HClO 4 , with dozens of explicit water molecules. The free energy changes and barriers were calculated by thermodynamic integration. Significant variations among the three models were observed, indicating the importance of considering the effect of an anion. The dissociation of adsorbed O 2 * and the association of a proton with an adsorbed O 2 * were often coupled with each other due to the reactivity of an adsorbed O* atom towards both H 2 O and solvated H+. [ABSTRACT FROM AUTHOR]

Insulated Gate Bipolar Transistor (IGBT) is the core power device in the fields of railways, new energy sources, and automobiles. The safe and reliable operation of IGBT is the basis to ensure the sustained and steady development of all walks of life. The junction-to-case thermal resistance of the IGBT power modules can manifest the fatigue degree of the solder layer. The saturation voltage drop manifests the aging degree of the IGBT bonding wire. Therefore, the IGBT reliability can be judged by a certain rule along with the external parameters such as the junction-to-case thermal resistance R th and the saturation voltage drop V ce. In order to grasp this rule, this study illustrates the correlations between the external parameters of IGBT and the number of power cycles. As a result, the functional relationships between the average change rate of junction-to-case thermal resistance and the number of power cycles (Δ R ¯ th — n) as well as the average saturation voltage drop rate of change and the number of power cycles (Δ V ¯ ce — n) have been gained from IGBT test samples. After obtaining these functional relationships, for any IGBT of the same model in working condition, a proposition of judging the aging degree can be obtained. Here, the aging degree of the IGBT is represented by a real number in the interval [0, 1] and the reliability of the above proposition is calculated from the standard deviation of the working lifetime of each test sample. The method proposed in this study can not only be used to judge the aging degree of IGBT, but also to estimate the remaining lifetime. • The IGBT reliability is judged by a certain rule along with the external parameters. • This study compares the fitting degree in exponential fitting and polynomial fitting method in temperatures. • The study identifies the functional relationship between average saturation voltage drop change rate and current effective working life cycle. [ABSTRACT FROM AUTHOR]

The Zn2+ doped In2.77S4 (Zn–In2.77S4) photocatalyst has been synthesized via a one-step hydrothermal method. The tetracycline was adopted to measure the photocatalytic performance of the as-fabricated Zn–In2.77S4 composites. The probable photocatalytic degradation mechanism of the as-prepared composites was also discussed. Experimental results reveal that doping Zn2+ into In2.77S4 can broaden the light absorption range and improve the recycle ability as well as the separation efficiency of photo-generated electron–hole pairs of pure In2.77S4. Moreover, as the doping amount of Zn2+ increased the photocatalytic efficiency of the as-obtained Zn–In2.77S4 composites appears the tendency of firstly increasing and then decreasing. When the molar ratio of Zn2+ to In3+ is 0.04:1 (4%), in 15 min, the photocatalytic efficiency of the as-developed Zn–In2.77S4 photocatalyst reaches to the maximum of 90.0%. It is higher than 31.8% of pure In2.77S4. Furthermore, superoxide radicals and holes play major roles in the process of photodegradation tetracycline. This research can supply a promising guide to solve antibiotics pollution in water under sunlight. [ABSTRACT FROM AUTHOR]

Hydrogen dinitrate anion, HNO3(NO3−), is a proton‐bound dimer with a very strong hydrogen bond. By employing ab initio molecular dynamics (AIMD) method, we studied the effects of the proton transfer and the rotation of the nitrates on the vibrational profiles of HNO3(NO3−)(H2O)n (n = 0–2). The AIMD results indicate that the structure of the n = 0 cluster is very flexible, even though its hydrogen bond is quite strong. Significant rotations around the hydrogen bond and frequent transfers of proton from HNO3 to NO3− are observed in AIMD simulations. Dynamic changes are therefore an important factor in understanding the broadening of vibrational features. For n = 1, the extent of structural fluctuation increases further, as H2O could move around the anion while the HNO3(NO3−) core also goes through structural changes. Its vibrational spectrum can be understood as a mixture of many isomers visited during AIMD simulations. By n = 2, the structure is stabilized around one isomer, with the linker between the two nitrates being H5O2+, rather than H+. Due to strong hydrogen bonds between nitrates and water molecules, this H5O2+ takes the extraordinary structure with the H+ localized on one H2O, rather than being shared. While this novel structure is stable during AIMD simulations, the dynamic fluctuations in hydrogen bond distances still produce significant broadening in its vibrational profile. [ABSTRACT FROM AUTHOR]

Abstract The stability, phase transition, magnetism and electronic properties of five different iron mononitride (FeN) phases are systematically studied using first-principles calculations. The results show that ZnS-FeN structure is the most stable phase at the equilibrium lattice, and the sequence of phase transition is according to ZnS→NiAs→wurtzite. Our magnetic analysis demonstrate that the ZnS, CsCl and wurtzite structures are nonmagnetic, while the NaCl and NiAs phases under high-pressure are magnetic, holding 2.27 and 1.61 μ B per Fe atom, respectively. The magnetic moments increase with increasing of the volume for all considered structures. Highlights • The properties of five FeN structures are studied using first principles calculations. • Enthalpy calculations show the sequence of phase transition is ZnS→NiAs→wurtzite • The transition pressures, from other four phases to the ZnS phase, are calculated. • The magnetic moments as a function of volume for all five structures are discussed. • The relations between the magnetic and electronic properties are analyzed. [ABSTRACT FROM AUTHOR]