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Hidden Markov model (HMM) is a popular statistical approach for modeling sequential data comprising continuous attributes, and it has been applied in finance, machine vision and other fields. Due to higher tolerance to outliers than Gaussian distribution, the multivariate student's t-distribution is used to serve as the observation emission distribution in continuous HMM (SHMM), which has been exploited to improve the performance for modeling sequential data. In this paper, a bag-of-models method based on the mixture of SHMMs is proposed to describe dynamic texture for dynamic texture classification, in which codebook is constructed with SHMMs. Specifically, a novel mixture model, mixture of SHMMs, is proposed to model and cluster the observation sequences of the dynamic texture. The parameter learning method is derived by using the expectation maximization (EM) algorithm. Then all components of the mixture of SHMMs are assembled to obtain the codewords and the bag-of-models based features are extracted for describing the dynamic texture. Finally, we demonstrate the effectiveness of the bag-of-models based on the mixture of SHMMs for dynamic texture classification on different benchmark datasets. The experimental results show the potential performance of the proposed approach by comparing with some existing dynamic texture classification methods. • The mixture of student's t-hidden Markov models (MixSHMM) is proposed to model the sequential data. • The MixSHMM model learning method based on the expectation maximization algorithm. • Clustering the dynamic texture patches with the model MixSHMM and building the bag-of-models for dynamic texture classification. [ABSTRACT FROM AUTHOR]

Organic pollutants, particularly nitrogen-rich explosives and carbon-rich dyes are generally degraded by different photocatalysts under either visible or ultraviolet light, leading to substantial waste and cost. Three photocatalysts with Z-scheme structures, Ag@AgBr/Cu 2 O-1, Ag@AgBr/Cu 2 O-2, and Ag@AgBr/Cu 2 O-3, are designed and synthesized employing a simple solvothermal and photoreduction technique to develop advanced photocatalyst materials that can degrade nitro substances under ultraviolet (UV) irradiation and organic dyes under visible-light irradiation. The structural characterization of Ag@AgBr/Cu 2 O-2 as determined through various spectroscopic techniques (e.g. XPS, XRD and TEM) reveal that the Z-scheme photocatalysts are composed of Ag, Cu 2 O and AgBr nanospheres with particle size less than 100 ​nm, while nano-Ag and nano-AgBr coupled to the surface of the Cu 2 O microspheres. Further investigations demonstrate that these photocatalysts exhibit a good UV–visible absorption range (200–800 ​nm) and outstanding photocatalytic degradation activity for two typical organic pollutants. Among them, Ag@AgBr/Cu 2 O-2 achieve a 100% degradation of trinitrotoluene (a common explosive) in 30 ​min under UV radiation, and a 99.2% degradation of rhodamine B (a typical dye) in 60 ​min under visible-light irradiation in the absence of UV light, demonstrating remarkable dual-band adaptability. Moreover, Ag@AgBr/Cu 2 O-2 displays superior stability, with a degradation rate of up to 85% after four cycles. The putative photocatalytic reaction mechanism is proposed based on the radical trapping experiment. [Display omitted] • The newly reported Z-scheme photocatalysts Ag@AgBr/Cu 2 O show good light absorption over the UV–visible range (200–800 ​nm). • These Z-scheme photocatalyst can degrade different organic pollutants under ultraviolet and visible-light irradiation. • The new Z-scheme photocatalyst can degrade at least 99% of trinitrotoluene and rhodamine B within 1 ​h in the UV–visible-light irradiation. • The reaction rate constant of Ag@AgBr/Cu 2 O-2 is 1.38 times that of Ag@AgBr and 74 times that of Cu 2 O. [ABSTRACT FROM AUTHOR]

Abstract: Objectives. : Despite great advances in therapeutic management, the mortality rate for ovarian cancer has remained relatively stable over the past 50 years. This study was designed to evaluate the expression of B7-H4 protein, recently identified as a potential molecular marker of breast and ovarian cancer by quantitative PCR analysis, in benign tumors, tumors of low malignant potential and malignant tumors of the ovary. Methods. : Archival formalin-fixed tissue blocks from serous, mucinous, endometrioid and clear cell ovarian tumors were evaluated by immunohistochemistry for the distribution of B7-H4 expression, and staining intensity was measured by automated image analysis. Univariate analyses were used to test for statistically significant relationships. Results. : B7-H4 cytoplasmic and membranous expression was detected in all primary serous (n = 32), endometrioid (n = 12), and clear cell carcinomas (n = 15), and in all metastatic serous (n = 23) and endometrioid (n = 7) ovarian carcinomas. By contrast, focal B7-H4 expression was detected in only 1/11 mucinous carcinomas. The proportion of positive cells and median staining intensity was greater in serous carcinomas than in serous cystadenomas or serous tumors of low malignant potential, and the differences were statistically significant (P < 0.0001 and P = 0.034, respectively). The median staining intensity was also significantly greater in endometrioid carcinomas than in endometriosis (P = 0.005). Conclusions. : The consistent overexpression of B7-H4 in serous, endometrioid and clear cell ovarian carcinomas and the relative absence of expression in most normal somatic tissues indicates that B7-H4 should be further investigated as a potential diagnostic marker or therapeutic target for ovarian cancer. [Copyright &y& Elsevier]

(a) The schematic illustration of ZnSn catalysts growth on Zn foil and (b) the possible reaction pathways for the electrochemical reduction of CO 2 to C 1 products on the surface of ZnSn catalyst. [Display omitted] The introduction of tin (Sn) into Zn-based catalyst can change its intrinsic properties of the electrochemically reduction of CO 2 to CO, obtaining a high formate yield. The electron transfer from Zn to Sn lowers down the d -band center of Sn, leading to a more reliable surface adsorption of the *OCHO intermediate and high formate selectivity. The obtained ZnSn catalyst enables formate formation with a drastically boosted Faradaic efficiency (FE) up to 94%, which is 2.04 and 1.34 times of pure Zn and Sn foils, respectively, indicating a synergistic effect between Zn and Sn. During the electrochemical CO 2 reduction reaction (eCO 2 RR) process, the morphology of the ZnSn catalyst evolved from nanoparticles to nanosheets, nanoneedles and collapsed structures, corresponding to the activation, stabilization and decay stages, respectively. This study provides a facile and controllable approach for the construction of novel bimetallic catalyst favoring formate selectivity based on the synergistic effect. [ABSTRACT FROM AUTHOR]

Abstract: Objectives and methods: B7-H4 (DD-O110), a member of the B7 family, negatively regulates T cell-mediated immune response. Previous studies have shown that B7-H4 is highly expressed in endometrioid ovarian cancers with relatively low levels of expression in normal ovary which was confirmed by Western blot. The present study was designed to localize B7-H4 expression by immunohistochemistry (IHC) in normal endometrium, endometrial hyperplasia and uterine endometrioid adenocarcinoma. The pattern of B7-H4 localization was compared with the IHC detection of CD3 and CD8-positive T lymphocytes and CD14 positive macrophages to investigate the role of B7-H4 in the regulation of tumor immune surveillance. B7-H4 expression was evaluated in apoptotic tumor cells. Results: The proportion and intensity of B7-H4 staining were increased in the progression from normal, hyperplastic and malignant endometrial glandular mucosa. B7-H4 showed a predominantly apical membranous staining (pattern 1) in normal and hyperplastic endometrial epithelium but showed intense circumferential membranous and cytoplasmic staining (pattern 2) in a majority of endometrioid carcinoma cases (p =0.018). The proportion of B7-H4 positive tumor cells and staining intensity was also higher in high risk tumors than in low risk tumors (p =0.001 and p =0.032, respectively). The proportion of B7-H4 positive tumor cells was inversely related to the number of CD3-positive and CD8-positive tumor-associated lymphocytes (TALs). There was a positive correlation between B7-H4 pattern 2 staining and both CD3-positive and CD8-positive tumor-infiltrating lymphocytes (TILs) (p =0.039 and p =0.031, respectively). Conclusions: B7-H4 is overexpressed in hyperplastic and malignant endometrial epithelium and is correlated with the number T cells associated with the tumor. These results suggest that B7-H4 overexpression may reflect a more aggressive biologic potential and may play a role in tumor immune surveillance mechanisms. [Copyright &y& Elsevier]

Obesity is often caused by the excess adipogenesis and regulated by long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). We performed this study to investigate the influence of Meg3 expression on adipogenesis and also the Meg3/miR-217/Dkk3 axis-mediated molecular mechanism in adipogenesis and angiogenesis. 3 T3-L1 preadipocytes were incubated with chemerin and transfected with Meg3-overexpressing (OE-Meg3) and Dkk3-overexpressing (OE-Dkk3) plasmids, siRNAs, and miR-217 mimics, inhibitor and scrambled sequences for 48 h or 72 h. The changes in cell proliferation, adipogenesis and angiogenesis ability in 3 T3-L1 preadipocytes was detected by using the corresponding assay. The expressions of related proteins were detected via western blot. Chemerin decreased miR-217 expression and increased Meg3 expression, meanwhile promoted the proliferation, adipogenesis and angiogenesis in 3 T3-L1 preadipocytes. Besides, OE-Meg3 exerted the synergistic effect on 3 T3-L1 preadipocytes when co-treated with chemerin. The target interactions between Meg3 and miR-217 as well as between miR-217 and Dkk3 were validated using dual-luciferase reporter system. SiMeg3 antagonized chemerin-induced changes, while the addition of miR-217 inhibitor attenuated siMeg3-induced changes in 3 T3-L1 preadipocytes. The proliferation, adipogenesis and angiogenesis in 3 T3-L1 preadipocytes were suppressed by miR-217 mimics, while promoted by the OE-Dkk3 Chemerin promoted the expression of fatty acid binding protein 4 and vascular endothelial growth factor (VEGF) proteins, and decreased the expression of cyclin D1, c-Myc, and β-catenin proteins. Meanwhile, these effects were further enhanced by OE-Meg3 or OE-Dkk3. However, the transfection of siMeg3, or miR-217 mimics, or siDkk3 reversed the previous changes. Meg3/miR-217/Dkk3 induced adipogenesis and angiogenesis in 3 T3-L1 preadipocytes via activating VEGF signaling pathway and inhibiting Wnt/β-catenin signaling pathway. • Meg3/miR-217/Dkk3 activates VEGF and inhibits Wnt/β-catenin signaling pathway. • The adipogenesis was regulated by Wnt signaling pathway and VEGF/FABP4. • Meg3/miR-217/Dkk3 induces adipogenesis and angiogenesis in 3 T3-L1 preadipocytes. [ABSTRACT FROM AUTHOR]

Short-term exposure to ambient PM 2.5 and PM 10 is associated with increased risk of mortality and hospital admissions for stroke. However, there is less evidence regarding the effect of exposure to PM 1 on stroke incidence. We estimated the incidence risk of stroke and the attributable fractions related to short-term exposure to ambient PM 1 , PM 2.5 and PM 10 in China. County-specific incidence of stroke was obtained from health statistics in years 2014–2019. We linked county-level mean daily concentrations of PM 1 , PM 2.5 and PM 10 with stroke incidence. We used the time stratified case-crossover design to estimate the associations between stroke incidence and exposure to PM 1 , PM 2.5 and PM 10. We also estimated the disease burden fractions attributable to PM 1 , PM 2.5 , and PM 10. The study included a total of 2,193,954 stroke, from which 1,861,331 were ischemic and 332,623 were hemorrhagic stroke. PM 1 , PM 2.5 , and PM 10 levels were associated with increased risks of total stroke and ischemic stroke at when assessing the associations in exposure at lag0−4 days. The increase of 10 μg/m3 in PM 1 , PM 2.5 , and PM 10 was associated with total stroke, and the relative risks were 1.012 (95% confidence interval: 1.008, 1.015), 1.006 (1.004, 1.007) and 1.003 (1.002, 1.004), while the associations with ischemic stroke were 1.013 (1.010, 1.017), 1.006 (1.005, 1.008) and 1.003 (1.002, 1.004), respectively. There was no significant association between PM and risk of hemorrhagic stroke. The attributable fractions of total stroke were 6.9% (5.1%, 8.5%), 5.6% (4.2%, 6.8%) and 5.6% (3.9%, 7.1%) for PM 1 , PM 2.5 , and PM 10 , respectively. PM 1 showed a stronger association with stroke, with a larger attributable fraction of outcomes, than PM 2.5 and PM 10. Clean air policies should target the whole scope of PM, including PM 1. • Exposure to PM 1 , PM 2.5 and PM 10 at lag0–4 day may lead to ischemic stroke. • PM 1 has stronger association with ischemic stroke incidence than PM 2.5 and PM 10. • Social deprivation may strengthen the PM-stroke association. • Future air clean policies should cover the scope of PM 1. [ABSTRACT FROM AUTHOR]

The phenolics from sea buckthorn (SP) exert various physiological functions. This study examined the interactions of SP on the digestive and physicochemical properties of rice (RS) and wheat starch (WS), as well as the stability of starch-phenolics during digestion. The predominant phenolics from SP were syringic acid (22.14%), gallic acid (15.23%), and catechin (11.45%). The addition of SP manipulated the rheology of starch pastes and affected the rearrangement and multi-scale structures of starch gels. Fourier transform infrared spectroscopy and X-ray diffraction revealed that SP interacted with starch mainly through non-covalent hydrogen bonds, leading to a loose starch gel structure. The content of rapidly digestible starch of RS and WS decreased by 5.66% and 7.75%; the predicted glycaemic index of RS (91.65) and WS (89.34) decreased to 81.81 and 80.84, respectively, when the addition level of SP reached 15%, due to the inhibition activity of SP against digestive enzymes, as well as the molecular reorganisation of starch. After the in vitro digestion, the bioaccessibility of SP in starch gels increased by a magnitude of 2.58-fold (RS) and 2.98-fold (WS). These results provide evidence of using SP as functional formulations in controlling gel-like foods structure behaviours and modulating the glycaemic response of starchy foods. • The main sea buckthorn phenolics (SP) were syringic acid, gallic acid, and catechin. • SP reduced the peak viscosity and breakdown value of starch significantly (p < 0.05). • IC 50 of ⍺-amylase and ⍺-glucosidase by SP were 0.26 mg/mL and 0.16 mg/mL. • SP interacted with starch via non-covalent H-bonds forming a loose gel structure. • SP facilitated the ordered structure of starch gels with anti-digestive properties. [ABSTRACT FROM AUTHOR]

Abstract: B7-H4 protein is expressed on the surface of a variety of immune cells and functions as a negative regulator of T cell responses. We independently identified B7-H4 (DD-O110) through a genomic effort to discover genes upregulated in tumors and here we describe a new functional role for B7-H4 protein in cancer. We show that B7-H4 mRNA and protein are overexpressed in human serous ovarian cancers and breast cancers with relatively little or no expression in normal tissues. B7-H4 protein is extensively glycosylated and displayed on the surface of tumor cells and we provide the first demonstration of a direct role for B7-H4 in promoting malignant transformation of epithelial cells. Overexpression of B7-H4 in a human ovarian cancer cell line with little endogenous B7-H4 expression increased tumor formation in SCID mice. Whereas overexpression of B7-H4 protected epithelial cells from anoikis, siRNA-mediated knockdown of B7-H4 mRNA and protein expression in a breast cancer cell line increased caspase activity and apoptosis. The restricted normal tissue distribution of B7-H4, its overexpression in a majority of breast and ovarian cancers and functional activity in transformation validate this cell surface protein as a new target for therapeutic intervention. A therapeutic antibody strategy aimed at B7-H4 could offer an exciting opportunity to inhibit the growth and progression of human ovarian and breast cancers. [Copyright &y& Elsevier]