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A combined model was developed using contrast-enhanced CT-based radiomics features and clinical characteristics to predict liver fibrosis stages in patients with chronic liver disease (CLD). We retrospectively analyzed multiphase CT scans and biopsy-confirmed liver fibrosis. 160 CLD patients were randomly divided into 7:3 training/validation ratio. Clinical laboratory indicators associated with liver fibrosis were identified using Spearman's correlation and multivariate logistic regression correlation. Radiomic features were extracted after segmenting the entire liver from multiphase CT images. Feature dimensionality reduction was performed using RF-RFE, LASSO, and mRMR methods. Six radiomics-based models were developed in the training cohort of 112 patients. Internal validation was conducted on 48 randomly assigned patients. Receptor Operating Characteristic (ROC) curves and confusion matrices were constructed to evaluate model performance. The radiomics model exhibited robust performance, with AUC values of 0.810 to 1.000 for significant fibrosis, advanced fibrosis, and cirrhosis. The integrated clinical-radiomics model had superior diagnostic efficacy in the validation cohort, with AUC values of 0.836 to 0.997. Moreover, these models outperformed established biomarkers such as the aspartate aminotransferase to platelet ratio index (APRI) and the fibrosis 4 score (FIB-4), as well as the gamma glutamyl transpeptidase to platelet ratio (GPR), in predicting the fibrotic stages. The clinical-radiomics model holds considerable promise as a non-invasive diagnostic tool for the assessment and staging of liver fibrosis in the patients with CLD, potentially leading to better patient management and outcomes. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to construct a predictive model for assessing the risk of development of neuropsychiatric systemic lupus erythematosus (NPSLE) among patients with SLE based on clinical, laboratory, and meteorological data. Methods: A total of 2232 SLE patients were included and were randomly assigned into training and validation sets. Variables such as clinical and laboratory data and local meteorological data were screened by univariate and least absolute shrinkage and selection operator (LASSO) logistic regression modelling. After 10-fold cross-validation, the predictive model was built by multivariate logistic regression, and a nomogram was constructed to visualize the risk of NPSLE. The efficacy and accuracy of the model were assessed by receiver operating characteristic (ROC) curve and calibration curve analysis. Net clinical benefit was assessed by decision curve analysis. Results: Variables that were included in the predictive model were anti-dsDNA, anti-SSA, lymphocyte count, hematocrit, erythrocyte sedimentation rate, pre-albumin, retinol binding protein, creatine kinase isoenzyme MB, Nterminal brain natriuretic peptide precursor, creatinine, indirect bilirubin, fibrinogen, hypersensitive C-reactive protein, CO, and mild contamination. The nomogram showed a broad prediction spectrum; the area under the curve (AUC) was 0.895 (0.858–0.931) for the training set and 0.849 (0.783–0.916) for the validation set. Conclusion: The model exhibits good predictive performance and will confer clinical benefit in NPSLE risk calculation. Key Points • Clinical, laboratory, and meteorological data were incorporated into a predictive model for neuropsychiatric systemic lupus erythematosus (NPSLE) in SLE patients. • Anti-dsDNA, anti-SSA, LYM, HCT, ESR, hsCRP, IBIL, PA, RBP, CO, Fib, NT-proBNP, Crea, CO, and mild contamination are predictors of the development of NPSLE and may have potential for research. • The nomogram has good predictive performance and clinical value and can be used to guide clinical diagnosis and treatment. [ABSTRACT FROM AUTHOR]

In this paper, the strong structural controllability of the leader-follower framework is discussed. Firstly, the authors analyze different edge augmentation methods to preserve the strong structural controllability of the path-bud topology. The following four cases are considered: Adding edges from the path to the bud; adding edges from the bud to the path; adding the reverse or forward edges to the path or bud; and adding both the reverse and forward edges to the path or bud. Then sufficient conditions are derived for the strong structural controllability of the new topologies which are generated by adding different edges. In addition, it is proved that rank[A B] = n is a necessary condition for the strong structural controllability. Finally, three examples are given to verify the effectiveness of the main results. [ABSTRACT FROM AUTHOR]

Objective: Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disease. Src homology 2 domain containing protein tyrosine phosphatase (SHP2) is a member of the protein tyrosine phosphatases (PTPs) family. To date, relationship between SHP2 and SLE pathogenesis is not elucidated. Method: We measured plasma levels of SHP2 in 328 SLE patients, 78 RA patients, 80 SS patients and 79 healthy controls by ELISA, and discussed association of SHP2 in SLE patients, potential of plasma SHP2 as a SLE biomarker. Moreover, histological and serological changes were evaluated by flow cytometry, HE/Masson examination, immunofluorescence test in pristane-induced lupus mice after SHP2 inhibitor injection to reveal role of SHP2 in lupus development. Results: Results indicated that SHP2 plasma levels were upregulated in SLE patients and correlated with some clinical, laboratory characteristics such as proteinuria, pyuria, and may be a potential biomarker for SLE. After SHP2 inhibitor treatment, hepatosplenomegaly and histological severity of the kidney in lupus mice were improved. SHP2 inhibitor reversed DCs, Th1, and Th17 cells differentiation and downregulated inflammatory cytokines (IL-4, IL-6, IL-10, IL-17A, IFN-γ and TNF-α) and autoantibodies (ANA, anti-dsDNA) production in pristane-lupus mice. Conclusion: In summary, SHP2 correlated with SLE pathogenesis and promoted the development of lupus. [ABSTRACT FROM AUTHOR]

Accurate prediction of the land reclamation settlement is a long-standing problem. Numerous empirical, analytical, and numerical methods have been proposed to solve this problem, but they require large domain knowledge and experiments for calibrating parameters. This study aims to apply deep learning algorithm, long short-term memory (LSTM), to predict the long-term settlement of land reclamation settlement and apply the LSTM-based model to land reclamations of Kansai International Airport (KIA) and then Chek Lap Kok Airport (CLKA). The LSTM-based model is first trained based on the historical settlement data of KIA, and its optimum configurations are determined in a trial-and-error fashion. The well-developed model is subsequently applied to predict the settlement of an embankment in CLKA. The results indicate that the LSTM-based model can accurately capture the long-term settlement of KIA. The developed model exhibits excellent generalization ability and can be directly applied to the other project, i.e. CLKA with the predicted settlement in good agreement with measured data. The model is verified generic and can thus be applied to similar projects. A Graphical User Interface is finally developed to make the LSTM-based model available for engineering practice. [ABSTRACT FROM AUTHOR]

A new and efficient output-feedback adaptive backstepping control strategy is developed to realize a finite-time output tracking control task for nonlinear output-constrained systems. The main characteristic of this strategy is to construct an asymmetric barrier Lyapunov function based on the performance functions and error variable to achieve finite-time tracking control. Because the system states are unknown, fuzzy state observer is set up to reconstruct the system states. Consequently, an observer-based fuzzy adaptive output-feedback controller is presented. The proposed control strategy ensures that the output tracking error meets the preassigned precision level throughout a pre-given time period, meanwhile, the output variable complies with time-varying restrictions for all time and other closed-loop signals are bounded. Lastly, two examples are employed for numerical simulation research to reveal the feasibility and availability of the developed control strategy. [ABSTRACT FROM AUTHOR]

This paper investigates the controllability of general linear discrete-time multi-agent systems with directed and weighted signed networks by using graphic and algebraic methods. The non-delay and delay cases are considered respectively. For the case of no time delay, the upper bound condition of the controllable subspace is given by using the equitable partition method, and the influence of coefficient matrix selection of individual dynamics is illustrated. For the case of single delay and multiple delays, the equitable partition method is extended to deal with time-delay systems, and some conclusions are obtained. In particular, some simplified algebraic criteria for controllability of systems with time delay are obtained by using augmented system method and traditional algebraic controllability criteria. [ABSTRACT FROM AUTHOR]

The investigation into the effects of acidizing treatment on the mechanical property of hot dry rocks (HDR) is beneficial for our understanding of the fracturing and stimulation mechanisms in HDR reservoirs. In this article, Brazilian disk tests were first carried out for hollow hot dry rocks with different internal diameters after acidizing treatments. The influences of acidizing treatments on the physical properties, tensile strength, and failure patterns of hot dry rock specimens were presented. Besides, the effects of the diameter of the internal hole on the peak load and failure patterns of the hot dry rock specimens were also investigated. The peak load decreases with the increase in the internal diameter. The results indicated that the acidizing treatments can dissolute the minerals, decrease rock mass, and tensile strength. The investigation of failure patterns demonstrated that the acidizing treatment is beneficial for the fracturing of hot dry rocks. The present study can provide some basic and theoretical data for the development of geothermal reservoir. [ABSTRACT FROM AUTHOR]

Background: Previous studies reported that IL-38 was abnormally expressed in patients with systemic lupus erythematosus (SLE). However, the involvement of IL-38 in the pathophysiology of SLE remains unknown. Methods: The therapeutic potential of IL-38 was tested in pristane-treated wild-type (WT) and IL-38−/− mice. Thus, SLE was induced via pristane in WT and IL-38−/− mice. Afterwards, the liver, spleen, and kidney of each mouse were obtained. The flow cytometric analysis of the immune cells, serologic expression of inflammatory cytokines and autoantibodies, renal histopathology, and inflammatory signaling were evaluated. Results: WT mice with pristane-induced lupus exhibited hepatomegaly, splenomegaly, severe kidney damages, increased lymphoproliferation, enhanced lymphoproliferation, and upregulated inflammatory cytokines, such as IL-6, IL-13, IL-17A, MIP-3α, IL-12p70, and IFNγ, and elevated levels of autoantibodies, such as ANA IgG, anti-dsDNA IgG, and total IgG. IL-38−/− mice whose lupus progressed, had elevated cells of CD14+, CD19+, CD3+, and Th1, upregulated inflammatory cytokines and autoantibodies, and severe pathological changes in kidney. Administration of recombinant murine IL-38 to pristane-treated IL-38−/− mice improved their renal histopathology, which depended on ERK1/2, JNK1/2, p38, NF-κB p65, and STAT5 signaling pathways. Conclusion: IL-38 regulates SLE pathogenesis. Furthermore, targeting IL-38 is critical in the treatment of SLE. [ABSTRACT FROM AUTHOR]

Polyacrylamide (HPAM) is commonly used as a thickener in water-based fracturing fluids due to its good solubility and thickening ability. However, drawbacks such as the formation of high temperature and high salinity in oil and gas production currently limit its use as a thickening agent for fracturing fluids. To solve this problem, a hydrophobic associating polymer, DSAM (acrylamide/2-acrylamido-2-methylpropanesulfonic acid/acrylic acid/hydrophobic monomer AMD-12), with a good temperature and salt resistance was synthesized via complex initiated polymerization. The molecular structure of the synthesized polymer DSAM was confirmed using IR and 1H NMR. The water solubility, thickening properties, and salt resistance of DSAM polymers were investigated. The results showed that the DSAM polymer solution's apparent viscosity initially decreased with the addition of NaCl. However, as the salt concentration further increased, the DSAM polymer solution's polarity also increased, as well as the hydrophobic association between molecules, resulting in a denser hydrophobic association network structure and an increase in the apparent viscosity of the polymer solution. The viscoelasticity test revealed that as the salt concentration increased, the viscoelastic polymer solution increased after initially decreasing, which was consistent with previous salt tolerance test results. Additionally, it exhibited superior temperature resistance, shear tolerance, and shear recovery capabilities compared with conventional HPAM. Meanwhile, the DSAM polymer can be completely broken down in the industry-standard time without residue. The benefits of DSAM polymers include salt thickening, high-temperature resistance, and thorough gel breaking. Thus, it has huge potential as a thickening agent for temperature-tolerant and salt-resistant fracturing fluid. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is commonly used in the stimulation of shale reservoirs for sustainable production and commercial development. The fracturing mechanisms of shale matrix, especially the roles of micro pores and minerals, is of vital importance for our understanding of hydraulic fracturing treatments. In this study, we induced hydraulic fractures in laboratory by performing hydraulic fracturing experiments, and observed two dimensional and three dimensional structures of micro-scale cracks in the shale matrix before and after hydraulic fracturing treatment using scanning electron microscopy (SEM) and focused ion beam scanning electron microscope (FIB-SEM) tests. We also counted the probability of different cracking modes and analyzed the relationships between crack pathways and the distributions of minerals, organic matters and pores. The results showed that the cracks mainly propagated along the boundaries of different minerals. The intergranular and organic pores can be captured by the induced cracks, and the intraparticle pores are hard to be reactivated. The present study provides us more evidences for further study of fracturing mechanism in shale matrix. [ABSTRACT FROM AUTHOR]

In this paper, a novel asymmetric Lyapunov–Krasovskii functional (LKF) method for the stability of Takagi–Sugeno (T–S) fuzzy systems with time-varying delay is proposed. This asymmetric LKF method is shown to effectively reduce conservatism compared with symmetric LKF method. For further improving the stability criterion, the method is combined with the improved membership-function-dependent technique. Two numerical examples are given to demonstrate the advantages of our method and stability criterion numerically. [ABSTRACT FROM AUTHOR]

Background: Lupus erythematosus is an autoimmune disease that causes damage to multiple organs ranging from skin lesions to systemic manifestations. Cutaneous lupus erythematosus (CLE) is a common type of lupus erythematosus (LE), but its molecular mechanisms are currently unknown. The study aimed to explore changes in the gene expression profiles and identify key genes involved in CLE, hoping to uncover its molecular mechanism and identify new targets for CLE. Method: We analyzed the microarray dataset (GSE109248) derived from the Gene Expression Omnibus (GEO) database, which was a transcriptome profiling of CLE cutaneous lesions. The differentially expressed genes (DEGs) were identified, and the functional annotation of DEGs was performed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Protein–protein interaction (PPI) network was also constructed to identify hub genes involved in CLE. Result: A total of 755 up-regulated DEGs and 405 down-regulated DEGs were identified. GO enrichment analysis showed that defense response to virus, immune response, and type I interferon signaling pathway were the most significant enrichment items in DEGs. The KEGG pathway analysis identified 51 significant enrichment pathways, which mainly included systemic lupus erythematosus, osteoclast differentiation, cytokine-cytokine receptor interaction, and primary immunodeficiency. Based on the PPI network, the study identified the top 10 hub genes involved in CLE, which were CXCL10, CCR7, FPR3, PPARGC1A, MMP9, IRF7, IL2RG, SOCS1, ISG15, and GSTM3. By comparison between subtypes, the results showed that ACLE had the least DEGs, while CCLE showed the most gene and functional changes. Conclusion: The identified hub genes and functional pathways found in this study may expand our understanding on the underlying pathogenesis of CLE and provide new insights into potential biomarkers or targets for the diagnosis and treatment of CLE. Key Points • The bioinformatics analysis based on CLE patients and healthy controls was performed and 1160 DEGs were identified • The 1160 DEGs were mainly enriched in biological processes related to immune responses, including innate immune response, type I interferon signaling pathway, interferon-γ-mediated signaling pathway, positive regulation of T cell proliferation, regulation of immune response, antigen processing, and presentation via MHC class Ib and so on • KEGG pathway enrichment analysis indicated that DEGs were mainly enriched in several immune-related diseases and virus infection, including systemic lupus erythematosus, primary immunodeficiency, herpes simplex infection, measles, influenza A, and so on • The hub genes such as CXCL10, IRF7, MMP9, CCR7, and SOCS1 may become new markers or targets for the diagnosis and treatment of CLE [ABSTRACT FROM AUTHOR]

Our understanding of progressive cracking in rock materials is very important for prediction of failure in rock engineering. Gathering three-dimensional observation of damage evolution process in rock materials has been a challenge. In this article, we realized imaging of cracking in oil shale during uniaxial compressive test using X-ray micro-computed tomography (CT) technology with a resolution of 11.27 μm. We also had fully resolved sequences of micro-cracks damage and cracks growth at different positions and stress levels. The results indicated that the micro cracks initiated at the boundary of specimens, and suffered continuous development during the process including branching, coalescence, and failure. The unstable propagation stage of cracks was assumed to be very close to the peak strength. Continuous loading enlarged the width of the cracks in the failed specimen. However, few new cracks were generated. Besides, several parameters such as the crack length (CL) and fracture network volume (FNV) were selected to quantitatively describe the cracking and damage evolution process. The cracking process, especially the propagation and formation of fracture network, can be precisely characterized these parameters. Our observations provide a powerful methodology for characterizing the dynamic changes in oil shale by fracturing treatment for the improvement and optimization of hydrocarbon recovery. [ABSTRACT FROM AUTHOR]

The burgeoning interest in synthesis and biological applications of 1,6-naphthyridines reflects the importance of 1,6-naphthyridines in the synthetic as well as medicinal chemistry fields. Specially, 1,6-naphthyridines are pharmacologically active, with variety of applications such as anticancer, anti-human immunodeficiency virus (HIV), anti-microbial, analgesic, anti-inflammatory and anti-oxidant activities. Although collective recent synthetic developments have paved a path to a wide range of functionalized 1,6-naphthyridines, a complete correlation of synthesis with biological activity remains elusive. The current review focuses on recent synthetic developments from the last decade and a thorough study of the anticancer activity of 1,6-naphthyridines on different cancer cell lines. Anticancer activity has been correlated to 1,6-naphthyridines using the literature on the structure–activity relationship (SAR) along with molecular modeling studies. Exceptionally, at the end of this review, the utility of 1,6-naphthyridines displaying activities other than anticancer has also been included as a glimmering extension. [ABSTRACT FROM AUTHOR]

Au nanorods were prepared through seed growth method. Their lengths and diameters were controlled by adjusting Ag+ content in the growth solution. Ethyl orthosilicate were hydrolyzed in alkali solutions to obtain SiO2-coated Au nanostructures. Au nanorods with ideal morphologies and sizes could only be obtained under the presence of a certain Ag+ concentration in the growth solution. Without Ag+, only some irregular nanoparticles were generated without nanorods. Longitudinal plasma absorption of Au nanorods shifts first to red shift and then to blue with the increase of Ag+ in the growth solution, while transverse plasma absorption hardly changes. However, longitudinal plasma absorption of silica-coated Au nanorods has a blue shift with the increase of the thickness of silica, while the transverse plasma has a slight red shift. Therefore, by coating Au nanorods with silica and by adjusting their aspect ratio by using different Ag+ concentration in the growth solution, Au nanoparticles can be synthesized for applications requiring absorption in specific UV regions. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated expression of circRNA in primary Sjögren's syndrome (pSS) patients so as to find novel biomarkers for pSS screening and discussed possible role of circRNA in pSS. We also evaluated expression profile of circRNA in systemic lupus erythematosus (SLE) patients. Methods: Microarray analysis detected circRNA expression in PBMCs from five paired pSS, SLE patients, and controls. Then, differentially expressed circRNAs were validated in 30 pSS patients as compared to 30 SLE patients, healthy controls. CircRNAs interacting with miRNAs were discussed by Arraystar's homemade miRNA target prediction software. ROC analysis assessed the diagnostic value. Results: We identified 234 differentially expressed circRNAs in pSS patients and verified five selected circRNAs (including hsa_circRNA_001264, hsa_circRNA_104121, hsa_circRNA_045355, hsa_circRNA_103461, hsa_circRNA_105034). Expression of hsa_circRNA_001264, hsa_circRNA_104121, and hsa_circRNA_045355 was strongly related to some clinical, laboratory parameters, and disease activity index in pSS patients. ROC analysis indicated potential diagnostic ability for the three circRNAs in pSS patients. One hundred and forty-eight circRNAs were differently expressed between lupus patients and controls. Conclusion: This study provides evidence that hsa_circRNA_001264, hsa_circRNA_104121, and hsa_circRNA_045355 might be biomarkers for pSS, correlate with pSS etiology. Key Points • Many circRNAs were dysregulated in pSS patients. • Differentially expressed circRNAs correlated with pSS clinical, laboratory features. • CircRNAs may be biomarkers for pSS. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is assumed to be a potentially important technology for the improvement of heat exchange rate in the exploitation and stimulation of geothermal resources. The propagation characteristics and aperture evolution of hydraulic fractures in enhanced geothermal system (EGS) are very important for the evaluation and optimization of field fracturing operation. In this article, we employed a series of hydraulic fracturing experiments with heterogeneous granite cores. The experimental monitoring demonstrates the different stages in fracturing treatment in granite cores, including initiation, propagation, and closure stages. The results indicate that, with the increase of confining pressure, the breakdown pressure increases, the maximum fracture width decreases, and the closure of fracture increases. The injection rates do not affect the breakdown pressure obviously. In addition, the fracture morphology was also illustrated by the detection using microscope and X-ray computer tomography (CT). Based on the observation of fractures and the experimental monitoring results, a pre-proposed model was employed to calculate the fracture aperture during fracturing treatment process. The results emphasize the dominant role of fracture closure in the evolution of fracture evolution process. Larger confining pressure results in larger closure proportion, the closure proportion of the fracture aperture even can exceed 90% when confining pressure is 30 MPa. [ABSTRACT FROM AUTHOR]

The exponential stability problem for complex-valued memristor-based recurrent neural networks (CVMRNNs) with time delays is studied in this paper. As an extension of real-valued memristor-based recurrent neural networks, CVMRNNs can be separated into real and imaginary parts and an equivalent real-valued system is formed. By constructing a novel Lyapunov function, a new sufficient condition to guarantee the existence, uniqueness, and global exponential stability of the equilibrium point for complex-valued systems is given in terms of M-matrix. The effectiveness of the theoretical result is shown by two numerical examples. [ABSTRACT FROM AUTHOR]

This paper considers the finite time state estimation problem of complex-valued bidirectional associative memory (BAM) neutral-type neural networks with time-varying delays. By resorting to the Lyapunov function approach, the Wirtinger inequality and the reciprocally convex approach, a delay-dependent criterion in terms of LMIs is established to guarantee the finite-time boundedness of the error-state system for the addressed system. Meanwhile, an effective state estimator is designed to estimate the network states through the available output measurements. Finally, a numerical example is presented to demonstrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

The effects of high pressure rheo-squeeze casting (HPRC) on the Fe-rich phases (FRPs) and mechanical properties of Al−17Si−(1,1.5)Fe alloys were investigated. The alloy melts were first treated by ultrasonic vibration (UV) and then formed by high-pressure squeeze casting (HPSC). The FRPs in the as-cast HPSC Al−17Si−1Fe alloys only contained a long, needle-shaped β-Al5FeSi phase at 0 MPa. In addition to the β-Al5FeSi phase, the HPSC Al−17Si−1.5Fe alloy also contained the plate-shaped δ-Al4FeSi2 phase. A fine, block-shaped δ-Al4FeSi2 phase was formed in the Al−17Si−1Fe alloy treated by UV. The size of FRPs decreased with increasing pressure. After UV treatment, solidification under pressure led to further refinement of the FRPs. Considering alloy samples of the same composition, the ultimate tensile strength (UTS) of the HPRC samples was higher than that of the HPSC samples, and the UTS increased with increasing pressure. The UTS of the Al−17Si−1Fe alloy formed by HPSC exceeded that of the Al−17Si−1.5Fe alloy formed in the same manner under the same pressure. Conversely, the UTS of the Al−17Si−1Fe alloy formed by HPRC decreased to a value lower than that of the Al−17Si−1.5Fe alloy formed in the same manner. [ABSTRACT FROM AUTHOR]

Porosity and permeability stress-sensitive behavior of sandstone is investigated through porosity and permeability measurements under hydrostatic compression. An empirical logarithm model is applied to the evaluation of stress sensitivity. Mercury injection, casting thin sections and scanning electron microscope are adopted to discuss the microscopic controlling factors and mechanisms of stress-sensitive behavior of sandstone. Disparities between laboratory-scale and field-scale data are also discussed. Experimental results show that both porosity and permeability decrease with increasing effective stress, and permeability is more sensitive to stress. The evolution of porosity and permeability with increasing effective stress follows the logarithmic model and can be classified into three stages: rapid decline, moderative decline and stable-slight decline stage. Stronger permeability stress sensitivity is observed in specimens with lower initial porosity and permeability, which is fundamentally controlled by the size and shape of void spaces as well as the content and distribution of soft minerals. While porosity stress sensitivity is observed to be discrete. Pore throat with small aspect ratio and irregular shape, fractures and minerals with lower elasticity modulus lead to the increase in permeability stress sensitivity of sandstone. The stress sensitivity characteristics are essentially the result of the dissimilar deformation responses of pores and framework grains under effective stress. Stress sensitivity evaluated in the laboratory usually does not completely represent the stress sensitivity in the field, due to stress release, drilling induced fractures and the difference of experimental and in situ conditions. [ABSTRACT FROM AUTHOR]

This paper studies the finite-time stability problem of complex-valued BAM neural networks with time delay. Firstly, based on a more suitable assumption for the complex-valued activation functions of the considered system, a tractable entire real-valued system is formed. Using nonlinear measure approach, a condition to ensure the existence and uniqueness of the equilibrium point for this system is derived. Then, a finite-time stability criterion of the equilibrium point is obtained in terms of LMIs by Lyapunov function approach. In the end, simulation examples are provided to verify the validity and advantages of the proposed conditions. [ABSTRACT FROM AUTHOR]

The H19 (rs2839698, rs3741219) and HOTAIR (rs920778) polymorphisms were related to many kinds of cancers. However, these polymorphisms have been scarcely explored in different autoimmune diseases. Here, we aimed to examine the association of the polymorphisms with susceptibility to or protection against systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and primary Sjögren's syndrome (pSS) among Chinese Han patients. We conducted a case-control study including 800 patients (300 with SLE, 350 with RA, and 150 with pSS) and 350 healthy control individuals. The polymorphisms were specified from genomic DNA using TaqMan genotyping assay on a 7300 real-time reverse transcription polymerase chain reaction system. H19 rs2839698 was not associated with SLE susceptibility and was not associated with RA and pSS, respectively ( P > 0.05). Similarly, we did not find significant differences of allele or genotype frequencies between SLE, RA, and pSS patients and healthy controls for H19 gene rs3741219 polymorphism ( P > 0.05). In addition, no significant evidence was detected for the relationship of HOTAIR rs920778 polymorphism with risk of these diseases. Our results suggested that H19 rs2839698, rs3741219, and HOTAIR rs920778 polymorphisms may not be involved in the genetic background of SLE, RA, and pSS in Chinese. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is a key technology in the exploitation of shale gas. Shale formations are a type of typical transverse isotropic material. The mechanisms that generate complex fracture networks during the fracturing process are of vital importance to hydraulic fracturing design. In this article, in order to analyze the effects of the anisotropic characteristics on the propagation of hydraulic fractures in shale formations, a series of hydraulic fracturing experiments were carried out with different stress conditions and injection rates. The effects of the anisotropic structure on the propagation of hydraulic fractures were revealed. The results show that the breakdown pressure increases with an increase in the injection rate of the fracturing fluid. It is suggested that the bedding plane angle of the shale formation has a great influence on the fracturing results. Additionally, as the deviator stress increases, the breakdown pressure decreases. From macroscopic observation of the fractures, different hydraulic fracture morphologies and hydraulic fracture propagation patterns were observed. [ABSTRACT FROM AUTHOR]

Based on the empirical electronic theory of solids and molecules (EET), the actual model for unit cell of cementite ( θ-FeC) was built and the valence electron structures (VES) of cementite with specified site and a number of Fe atoms substituted by alloying atoms of M ( M=Cr, V, W, Mo, Mn ) were computed by statistical method. By defining P as the stability factor, the stability of alloyed cementite with different numbers and sites of Fe atoms substituted by M was calculated. Calculation results show that the density of lattice electrons, the symmetry of distribution of covalent electron pairs and bond energy have huge influence on the stability of alloyed cementite. It is more stable as M substitutes for Fe than for Fe. The alloyed cementite is the most stable when Cr, Mo, W and V substitute for 2 atoms of Fe at the sites of Nos. 2 and 3 (or No. 6 and No. 7). The stability of alloyed cementite decreases gradually as being substitutional doped by W, Cr, V, Mo and Mn. [ABSTRACT FROM AUTHOR]

Environmental factors play an important role in the development of rheumatoid arthritis (RA). Among these factors, smoking is generally considered to be an established risk factor for RA. Data regarding the impact of diet on risk of RA development is limited. This study assessed the impact of dietary patterns on RA susceptibility in Chinese populations. This was a large scale, case-control study composed of 968 patients with RA and 1037 matched healthy controls. Subjects were recruited from 18 teaching hospitals. Socio-demographic characteristics and dietary intakes 5 years prior to the onset of RA were reported by a self-administered questionnaire. Differences in quantity of consumption between cases and controls were analyzed by Student's t test. Multiple logistic regression analysis was applied to identify independent dietary risk factor(s) responsible for RA susceptibility. Compared to healthy individuals, RA patients had decreased consumption of mushrooms ( P = 0.000), beans ( P = 0.006), citrus ( P = 0.000), poultry ( P = 0.000), fish ( P = 0.000), edible viscera ( P = 0.018), and dairy products ( P = 0.005). Multivariate analyses revealed that several dietary items may have protective effects on RA development, such as mushrooms (aOR = 0.669; 95%CI = 0.518-0.864, P = 0.002), citrus fruits (aOR = 0.990; 95%CI = 0.981-0.999, P = 0.04), and dairy products (aOR = 0.921; 95%CI 0.867-0.977, P = 0.006). Several dietary factors had independent effects on RA susceptibility. Dietary interventions may reduce the risk of RA. [ABSTRACT FROM AUTHOR]

This paper revisits the problem of $$H_{\infty }$$ filtering design for nonlinear systems with time-varying delay through Takagi-Sugeno (T-S) fuzzy models. By applying the fuzzy line-integral Lyapunov function, a new sufficient condition for the existence of the fuzzy $$H_{\infty }$$ filter design is established in terms of linear matrix inequalities. The present method provides improvements and produces better results than existing ones in the literature. Two examples are given to show the advantages and effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

In this paper, a tracking control problem is investigated for a class of switched stochastic nonlinear uncertain systems with unknown dead-zone input. By using the common Lyapunov function method and backstepping technique, a common controller and an uniform adaptive mechanism are constructed, and a novel adaptive fuzzy control scheme is developed. It is proved that the proposed control method can guarantee that all the signals in the closed-loop system are bounded in probability and the tracking error is convergent to a neighborhood of the origin under arbitrary switching. Finally, simulation results are provided to show the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Coking wastewater treatment plant (CWWTP) represents a typical point source of polycyclic aromatic hydrocarbons (PAHs) to the water environment and threatens the safety of drinking water in downstream regions. To enhance the removal of residual PAHs from bio-treated coking wastewater, a pilot-scale O/ultraviolet (UV) fluidized bed reactor (O/UV FBR) was designed and different operating factors including UV irradiation intensity, pH, initial concentration, contact time, and hydraulic retention time (HRT) were investigated at an ozone level of 240 g h and 25 ± 3 °C. A health risk evaluation and cost analysis were also carried out under the continuous-flow mode. As far as we know, this is the first time an O/UV FBR has been explored for PAHs treatment. The results indicated that between 41 and 75 % of 18 target PAHs were removed in O/UV FBR due to synergistic effects of UV irradiation. Both increased reaction time and increased pH were beneficial for the removal of PAHs. The degradation of the target PAHs within 8 h can be well fitted by the pseudo-first-order kinetics ( R > 0.920). The reaction rate was also positively correlated with the initial concentrations of PAHs. The health risk assessment showed that the total amount of carcinogenic substance exposure to surface water was reduced by 0.432 g day. The economic analysis showed that the O/UV FBR was able to remove 18 target PAHs at a cost of US$0.34 m. These results suggest that O/UV FBR is efficient in removing residuals from CWWTP, thus reducing the accumulation of persistent pollutant released to surface water. [ABSTRACT FROM AUTHOR]

This paper considers the problem of adaptive fuzzy control of a class of single-input/single-output (SISO) nonlinear stochastic systems in non-strict-feedback form. Fuzzy logic systems are used to approximate the uncertain nonlinearities and backstepping technique is utilized to construct an adaptive fuzzy controller. The proposed controller guarantees that all the signals in the resulting closed-loop system are bounded in probability. The main contribution of this note lies in providing a control strategy for a class of nonlinear systems in nonstrict-feedback form. Simulation result is used to test the effectiveness of the suggested approach. [ABSTRACT FROM AUTHOR]

The purpose of this study was to estimate the prevalence rates of probable posttraumatic stress disorder (PTSD) and depression and to explore potential risk factors among child and adolescent survivors 1 year following the 2008 Wenchuan earthquake. 3052 participants were administered the Child PTSD Symptom Scale, the Center for Epidemiologic Studies Depression Scale for Children, and the earthquake experience scale. Results indicated that the prevalence rates of probable PTSD and depression were 8.6 and 42.5 %, respectively. Demographic variables (i.e., age and gender) and most aspects of earthquake experiences (i.e., direct exposure, close ones' exposure, fear for the safety of close ones, prior exposure to trauma, living location, and house damage, with the exception of type of housing) made unique contributions to PTSD and depressive symptoms. In addition, the moderating effect of gender on the relationships between age and PTSD and depressive symptoms was significant. In conclusion, depression was a more common psychological response than was PTSD among child survivors 1 year following the Wenchuan earthquake. Age and gender were risk factors for both PTSD and depressive symptoms. Furthermore, older female survivors exhibit more severe PTSD and depressive symptoms. Additionally, several aspects of earthquake experiences (i.e., direct exposure, close ones' exposure, fear for the safety of close ones, prior exposure to trauma, living location, and house damage) was also important for the development and maintenance of PTSD and depressive symptoms. [ABSTRACT FROM AUTHOR]

Identification and removal of polycyclic aromatic hydrocarbons (PAHs) were investigated at two coke plants located in Shaoguan, Guangdong Province of China. Samples of raw coking wastewaters and wastewaters from subunits of a coke production plant were analyzed using gas chromatography-mass spectrometry (GC/MS) to provide a detailed chemical characterization of PAHs. The identification and characterization of PAH isomers was based on a positive match of mass spectral data of sample peaks with those for PAH isomers in mass spectra databases with electron impact ionization mass spectra and retention times of internal reference compounds. In total, 270 PAH compounds including numerous nitrogen, oxygen, and sulfur heteroatomic derivatives were positively identified for the first time. Quantitative analysis of target PAHs revealed that total PAH concentrations in coking wastewaters were in the range of 98.5 ± 8.9 to 216 ± 20.2 μg/L, with 3-4-ring PAHs as dominant compounds. Calculation of daily PAH output from four plant subunits indicated that PAHs in the coking wastewater came mainly from ammonia stripping wastewater. Coking wastewater treatment processes played an important role in removing PAHs in coking wastewater, successfully removing 92 % of the target compounds. However, 69 weakly polar compounds, including PAH isomers, were still discharged in the final effluent, producing 8.8 ± 2.7 to 31.9 ± 6.8 g/day of PAHs with potential toxicity to environmental waters. The study of coking wastewater herein proposed can be used to better predict improvement of coke production facilities and treatment conditions according to the identification and removal of PAHs in the coke plant as well as to assess risks associated with continuous discharge of these contaminants to receiving waters. [ABSTRACT FROM AUTHOR]

The research studied the combined effects of ultrasonic vibration (USV) and manganese on the Fe-containing inter-metallic compounds and mechanical properties of AI-17Si-3Fe-2Cu-1 Ni (wt.%) alloys. Theresults showed that, without USV, the alloys with 0.4wt.% Mn or 0.8wt.% Mn both contain a large amount of coarse plate-like δ-AI4(Fe,Mn)Si2 phase and long needle-like β-AI5(Fe,Mn)Si phase. When the Mn contentchanges from 0.4wt.% to 0.8wt.% in the alloys, the amount and the length of needle-like β-AI5(Fe,Mn)Si phasedecrease and the plate-like 5-AI4(Fe,Mn)Si2 phase becomes much coarser. After USV treatment, the Fecontainingcompounds in the alloys are refined and exist mainly as 5-AI4(Fe,Mn)Si2 particles with an averagegrain size of about 20 jjm, and only a small amount of β-AI5(Fe,Mn)Si phase remains. With USV treatment,the ultimate tensile strengths (UTS) of the alloys containing 0.4wt.%Mn and 0.8wt.%Mn at room temperatureare 253 MPa and 262 MPa, respectively, and the ultimate tensile strengths at 350 °C are 129 MPa and 135MPa, respectively. It is considered that the modified morphology and uniform distribution of the Fe-containing inter-metallic compounds, which are caused by the USV process, are the main reasons for the increase in thetensile strength of these two alloys. [ABSTRACT FROM AUTHOR]

This paper focuses on the problem of the adaptive neural control for a class of a perturbed pure-feedback nonlinear system. Based on radial basis function (RBF) neural networks' universal approximation capability, an adaptive neural controller is developed via the backstepping technique. The proposed controller guarantees that all the signals in the closed-loop system are bounded and the tracking error eventually converges to a small neighborhood around the origin. The main advantage of this note lies in that a control strategy is presented for a class of pure-feedback nonlinear systems with external disturbances being bounded by functions of all state variables. A numerical example is provided to illustrate the effectiveness of the suggested approach. [ABSTRACT FROM AUTHOR]

This note considers the problem of direct adaptive neural control for a class of nonlinear single-input/single-output (SISO) strict-feedback stochastic systems. The variable separation technique is introduced to decompose the coefficient functions of the diffusion term. Radical basis function (RBF) neural networks are used to approximate unknown and desired control signals, then a novel direct adaptive neural controller is constructed via backstepping. The proposed adaptive neural controller guarantees that all the signals in the closed-loop system remain bounded in probability. A main advantage of the proposed controller is that it contains only one adaptive parameter needed to be updated online. Simulation results demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of delay-dependent mean square exponential stability for a class of delayed stochastic Hopfield neural networks with Markovian jump parameters. The delays here are time-varying delays. Based on a new Lyapunov–Krasovskii functional, delay-dependent stability conditions are derived by means of linear matrix inequalities (LMIs). It is shown that the proposed results can contain some existing stability conditions as a special case. Finally, three numerical examples are given to illustrate the effectiveness of the proposed method, and the simulations show that our results are less conservative than the existing ones. [ABSTRACT FROM AUTHOR]

Taking advantage of measurements from an in situ monitoring program and an elastoplastic model using the finite-difference method, this paper simulates and evaluates the deformation and stability of a tunnel in soft argillaceous shale. The elastoplastic model is implemented in FLAC3D program to simulate the deformation and the stress of the soft argillaceous shale during construction. In situ tests performed in the soft argillaceous shale tunnel show that the results from numerical simulations are in good quantitative agreement with the measured in situ data. Results of the simulations also suggest that deformation rate is high during the initial phase of tunnel excavation, compared with the later phase, but the time to reach a steady state remains long. Entire primary support has been undergoing plastic deformation before construction of the secondary lining, which takes the form of so-called “shear yield” from the middle to the bottom of the arch. Some auxiliary measures, especially the anchor, should be applied to enhance stabilization because of the large compressive stress located at the arch springing of the tunnel. The methodology applied in this article can be used to investigate the effect of construction on the performance of tunnels in soft argillaceous shale. [ABSTRACT FROM AUTHOR]

Slack variables approach is an important technique for tackling the delay-dependent stability problem for systems with time-varying delay. In this paper, a new delay-dependent stability criterion is presented without introducing any slack variable. The technique is based on a simply integral inequality. The result is shown to be equivalent to some existing ones but includes the least number of variables. Thus, redundant selection and computation can be avoided so that the computational burden can be largely reduced. Numerical examples are given to illustrate the effectiveness of the proposed stability conditions. [ABSTRACT FROM AUTHOR]

Maternal food restriction (FR) during pregnancy results in decreased body weight with increased plasma leptin. To address this paradox, we investigated the effects of FR during pregnancy on growth and leptin levels in maternal, placental, and fetal sites. From embryonic day E10, control pregnant rats received ad libitum (AdLib) food, whereas study rats were 50% FR. At gestational ages, E16 and E20, the alterations in maternal body composition, retroperitoneal versus subcutaneous adipose leptin expression, and plasma leptin levels were studied. Furthermore, these changes were related to non-pregnant (NP) status and placental/fetal growth and leptin levels. As compared to NP, both FR and AdLib dams showed a progressive increase in body and lean body mass. However, total body fat was reduced in FR dams but remained unchanged in AdLib dams. Furthermore, plasma leptin levels in FR dams were markedly increased at E20 unlike AdLib dams, which showed moderate increments at E16 and E20. Additionally, FR dams showed significantly decreased leptin expression in subcutaneous and notably unaltered levels in retroperitoneal adipose tissue, suggesting an alternate source of elevated maternal plasma leptin. More importantly, the FR dams had reduced placental weights with paradoxical increased leptin expression at both gestations. Thus, increased plasma leptin levels at E20 in maternal FR pregnancies may be explained, in part, by upregulation of placental leptin. Despite maternal and placental hyperleptinemia during FR pregnancies, the growth-restricted FR fetus had reduced leptin levels. These findings have important implications for pregnancy outcome and fetal growth. [ABSTRACT FROM AUTHOR]

A recently proposed model coupling with the solid-fluid of the saturated sand was utilized to study the deformation band. Based on the critical state plasticity model by Borja and Andrade, the hydraulic conductivity tensor was naturally treated as a function of the spatial discretization matrix about the displacement and the stress field, allowing a more realistic representation of the physical phenomenon. The fully Lagrangian form of the Darcy law was resolved by Piola algorithm, and then the flow law was gained, leading to the implementation of a modified model of the saturated sand. Then the criterion for the onset of localization was derived and utilized to detect instability. The constitutive model was implemented in a finite element program coded by FORTRAN, which was used to predict the formation and development of shear bands in plane strain compression of saturated sand. At last, the formation mechanism of the shear band was discussed. It is shown that the model works well, and the simulation sample bifurcates at 1.18% axial strain, which is in a good qualitative agreement with the experiment. The pore pressure greatly affects the onset and development of the deformation band, and it obviously increases around the localization-prone regions with the direction toward the outer side of the normal of the shear band, while the pore stress flows nearly horizontally and is distributed equally far away the shear band region. [ABSTRACT FROM AUTHOR]

This paper focuses on the problem of delay-range-dependent L 2– L ∞ filter design for stochastic systems with time-varying delay. The time delay varies in an interval. A delay-range-dependent sufficient condition is formulated in terms of linear matrix inequalities (LMIs), which guarantees the existence of a linear filter. The proposed filter ensures that the filtering error system is stochastically asymptotically stable and that its L 2– L ∞ performance satisfies a prescribed level. The corresponding filter design is cast into a convex optimization problem which can be efficiently handled by using standard numerical algorithms. Finally, a numerical example is given to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, the problem of delay-dependent robust H ∞ control for uncertain stochastic systems with state and input delays is investigated. The time delays are assumed to be bounded and time varying and the uncertainties are assumed to be norm bounded. By using the Lyapunov functional method, a new delay-dependent robust H ∞ control scheme is presented in terms of linear matrix inequalities (LMIs). Some numerical examples are given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]