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Allyl ether naphthol resin (ANPF) was synthesized by introducing 1,5‐dihydroxynaphthalene and 2,7‐dihydroxynaphthalene into phenolic resin and was copolymerized with 4,4′‐bismaleimidodiphenylmethane resin (BDM) to obtain allyl ether naphthol‐modified bismaleimide resins (15‐ANPF‐BDM and 27‐ANPF‐BDM). The resulting thermal stability and glass transition temperature (Tg) were explored by thermogravimetric and dynamic mechanical analyses. The char yield of 15‐ANPF‐BDM at a temperature of 800°C was 46.0%. Additionally, the Tg of 15‐ANPF‐BDM was measured as 311°C, which is an increase of 44°C compared to that of c. The mechanical properties of the ANPF‐BDM/quartz fiber (Qf) composites were also investigated. The results reveal that ANPF‐BDM/Qf composites exhibit similar mechanical strength to APF‐BDM/Qf composites at room temperature. In addition, the mechanical properties of the ANPF‐BDM/ Qf composites demonstrated significant improvement in mechanical properties retained significantly improved at 200°C, with a 68% flexural strength retention and a 96% interlaminar shear retention of 15‐ANPF‐BDM/Qf composites. Thus, ANPF‐BDM/Qf composites exhibit outstanding mechanical properties at 200°C. [ABSTRACT FROM AUTHOR]

Although various aerogels with electromagnetic wave (EMW) absorbing properties have been extensively explored, the development of aerogels with excellent wave absorption performance, low density, and great heat resistance has still met profound challenges. Herein, polysilazane hybrid phenolic resin aerogels (PRVS aerogels) were prepared using the vinyl addition reaction of polysilazane and cross‐linking reaction between polysilazane and phenolic resin. A SiOCN ceramic aerogel with multistage pore structure was prepared via a simple and quick freeze‐drying method and polymer‐derived ceramic (PDC) methods. The SiOCN ceramic aerogels exhibited low density (0.15–0.27 g/cm3), good heat‐shielding (thermal conductivity in the range of 0.03–0.04 W/(m·K)), and excellent wave absorption performance (i.e., RL was about –31.6 dB@16.48 GHz and EAB was 3.85 GHz when the thickness of the ceramic aerogel was 1.2 mm). Hence, the ceramic aerogel absorbing materials could meet the requirements of "wide absorption bandwidth, strong reflection loss, lightweight and thi thickness". Moreover, the mechanism of low weight, heat insulation, and wave absorption properties of the aerogels were also investigated. We believe this work is of great significance in ceramic aerogels prepared by traditional polymers, which may provide new opportunities for new ceramic aerogels with applications ranging from EMW absorption to aerospace and information technology. [ABSTRACT FROM AUTHOR]

In this study, 1,5‐dihydroxynaphthalene moiety was introduced into a novolac resin structure, and propargyl ether naphthalene phenolic resin (PNPF) was synthesized by the Williamson etherification reaction, which improved the heat resistance of the resin and its processability. The structure of the PNPF resin was characterized using 1H NMR and FTIR analysis, and its processability, heat resistance, thermal expansion, and dielectric properties were evaluated. The results revealed that the addition of 1,5‐dihydroxylhine, increased the reaction activity of the PNPF resin, and decreased its initial curing temperature, with the resin exhibiting excellent processability. The cured resin also showed excellent heat resistance and thermomechanical properties. The 5% weight loss temperature (Td5) and glass transition temperature (Tg) of the resin increased to 437.61 and 362.04°C, respectively, while the coefficient of thermal expansion decreased from 60.17 to 44.52 ppm, with a reduction of 26.01%. Moreover, the dielectric constant and dielectric loss of the cured resin were 3.02 and 0.00239, respectively. [ABSTRACT FROM AUTHOR]

Four poly(benzoxazine‐co‐siloxane) oligomers (PBcSs) were successfully synthesized by improving the synthesis step and controlling the ratio of phenol, bisphenol A, 1,3‐bis(3‐aminopropyl)tetramethyldisiloxane, m‐aminophenyl acetylene, and formaldehyde; the resulting compounds all exhibited good processing properties. Siloxane addition can significantly improve the toughness of the polybenzoxazines. Additionally, compared with the PBcSs containing only phenol structure, the introduction of bisphenol A has a decelerating effect on the polymerization process of the benzoxazine oligomer, which leads to an increase in the exothermic peak temperature. Simultaneously, the PBcS containing bisphenol A also exhibits a higher glass transition temperature and increased thermal stability, but reduced flexural strength. Conversely, compared to the benzoxazine oligomers that do not contain alkynyl groups, the introduction of the terminal alkynyl group can accelerate the polymerization process, decrease the exothermic peak temperature, significantly increase the glass transition temperature, and greatly improve the heat resistance; the 5% thermal decomposition temperature of cured product is increased by up to 101°C. Furthermore, under conditions that ensure high flexural strength, appropriate alkynyl content can also significantly increase the material's flexural modulus. [ABSTRACT FROM AUTHOR]

Benzoxazines have been widely used in many fields, such as the aerospace, electronics, and automotive industries; however, these resins exhibit nonrecyclable nature and limited strength (for their brittleness). Introducing reversible covalent bonds in benzoxazines is expected to address these issues. Herein, two‐benzene‐ring‐conjugated Schiff‐base benzoxazine was successfully synthesized using a designed strategy. Using this strategy, possible side reactions, such as the transimination of the Schiff‐base, were prevented when preparing the target product via the traditional Mannich reaction. The cured benzoxazine could chemically degrade under acidic conditions and it undergoes controllable degradation when the temperature, acidity, and solvent are changed. The synthesized benzoxazine forms noticeable liquid crystals when heated to its melting point. Its glass transition temperature also reaches 265°C and the char yield at 800°C is 60.8%, considerably higher than that of traditional bisphenol A‐aniline based benzoxazine (BA‐a). Upon blending with epoxy (EP), the mechanical properties of the copolymers are significantly improved. With increasing benzoxazine content, the tensile strength of the copolymers increases from 63.6 to 95.2 MPa, an increase of ~50%. The rigid Schiff‐base structure is uniformly incorporated into the crosslinked network of EP and the EP curing agent via a transimination reaction during curing, thereby significantly improving the tensile modulus and strength of the composite material. [ABSTRACT FROM AUTHOR]

Purpose: Medical image segmentation is critical for many medical image analysis applications. 3D convolutional neural networks (CNNs) have been widely adopted in the segmentation of volumetric medical images. The recent development of channelwise and spatialwise attentions achieves the state‐of‐the‐art feature representation performance. However, these attention strategies have not explicitly modeled interdependencies among slices in 3D medical volumes. In this work, we propose a novel attention module called progressive attention module (PAM) to explicitly model the slicewise importance for 3D medical image analysis. Methods: The proposed method is composed of three parts: Slice Attention (SA) block, Key‐Slice‐Selection (KSS) block, and Channel Attention (CA) block. First, the SA is a novel attention block to explore the correlation among slices for 3D medical image segmentation. SA is designed to explicitly reweight the importance of each slice in the 3D medical image scan. Second, the KSS block, cooperating with the SA block, is designed to adaptively emphasize the critical slice features while suppressing the irrelevant slice features, which helps the model focus on the slices with rich structural and contextual information. Finally, the CA block receives the output of KSS as input for further feature recalibration. Our proposed PAM organically combines SA, KSS, and CA, progressively highlights the key slices containing rich information for the relevant tasks while suppressing those irrelevant slices. Results: To demonstrate the effectiveness of PAM, we embed it into 3D CNNs architectures and evaluate the segmentation performance on three public challenging data sets: BraTS 2018 data set, MALC data set, and HVSMR data set. We achieve 80.34%, 88.98%, and 84.43% of the Dice similarity coefficient on these three data sets, respectively. Experimental results show that the proposed PAM not only boosts the segmentation accuracy of the standard 3D CNNs methods consistently, but also outperforms the other attention mechanisms with slight extra costs. Conclusions: We propose a new PAM to identify the most informative slices and recalibrate channelwise feature responses for volumetric medical image segmentation. The proposed method is evaluated on three public data sets, and the results show improvements over other methods. This proposed technique can effectively assist physicians in many medical image analysis. It is also anticipated to be generalizable and transferable to assist physicians in a wider range of medical imaging applications to produce greater value and impact to health. [ABSTRACT FROM AUTHOR]

Inflammasomes are a group of multiprotein signaling complexes located in the cytoplasm. Several inflammasomes have been identified, including NLRP1, NLRP2, NLRP3, AIM2, and NLRC4. Among them, NLRP3 was investigated in most detail, and it was reported that it can be activated by many different stimuli. Increased NLRP3 protein expression and inflammasome assembly lead to caspase‐1 mediated maturation and release of IL‐1β, which triggers inflammation and pyroptosis. The activation of the NLRP3 inflammasome has been widely reported in studies of tumors and neurological diseases, but relatively few studies on the cardiovascular system. Ventricular remodeling (VR) is an important factor contributing to heart failure (HF) after myocardial infarction (MI). Consequently, delaying VR is of great significance for improving heart function. Studies have shown that the NLRP3 inflammasome plays an essential role in the process of VR. Here, we reviewed the latest studies on the activation pathway of the NLRP3 inflammasome, focusing on the effects of the NLRP3 inflammasome in primary cells during VR, and finally discuss future research directions in this field. [ABSTRACT FROM AUTHOR]

Silicon‐containing arylacetylene resins (PSAs) can be used in high temperature environment due to their excellent thermal stability. However, their high temperature oxidation is still bottle‐neck for further application. Herein, Materials Genome Initiative (MGI) was utilized to identify a target monomer, 3,6‐diethynylcarbazole (DEC), to design new PSAs with enhanced antioxidant properties and heat resistance. After incorporation of DEC, the thermal curing behavior observed using differential scanning calorimetry (DSC), fourier transform infrared (FTIR) and thermogravimetric analysis (TGA) revealed that obtained silicon‐containing carbazolylacetylene resins (PSA‐VBC) can exhibit hydroamination reaction to decrease the initial curing temperature. And the temperature at 5% weight loss (Td5) occurred in cured copolymers ranged from 665°C to 691°C, which showed excellent heat resistance. Moreover, the oxidation behavior of cured resins was investigated by thermogravimetric/derivative thermogravimetry (TG/DTG), X‐ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). Upon the incorporation of DEC, the thermal oxidation decomposition temperature of PSA‐VBC were 100°C higher than those observed for PSAs, which also proved by XPS analysis results that the oxygen content of PSA‐VBC solidified oxide was lower than that of PSAs. In addition, the surface morphology of cured PSA‐VBC resins still maintained integrity after oxidation at 400°C for 2 hr, which showed excellent oxidation resistance. [ABSTRACT FROM AUTHOR]

QiShenYiQi pill (QSYQ), a traditional Chinese medicine, is well known for improving the myocardial remodelling, but the dose‐effect relationship of its intervention in the reparative myocardial fibrosis is still unclear. We investigated the effect of QSYQ on the reparative myocardial fibrosis in cardiac myosin‐induced rats and explored its mechanism of action by regulating autophagy. The results indicated that QSYQ increased LVEF and LVFS, and decreased the LVEDD, LVESD, HMI, LVMI, myocardial inflammation histology score, and collagen volume fraction in a dose‐dependent manner. In addition, QSYQ declined the number of autophagosomes, down‐regulated the expression of myocardial Beclin‐1 and LC3B, up‐regulated the expression of myocardial p62 and increased the ratios of myocardial p‐PI3K/PI3K, p‐Akt/Akt and p‐mTOR/mTOR. We provided evidence for that QSYQ could inhibit excessive myocardial autophagy by regulating the PI3K/Akt‐mTOR pathway and can be a potential therapeutic approach in treating the cardiovascular diseases such as myocarditis and dilated cardiomyopathy. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the validity of noninvasive prenatal diagnosis (NIPD) based on direct haplotype phasing without the proband or other family members and its feasibility for clinical application in the case of Duchenne muscular dystrophy (DMD).Methods: Thirteen singleton-pregnancy families affected by DMD were recruited. The pathogenic variants in the pregnant females have been identified by multiplex ligation-dependent probe amplification (MLPA). We resolved maternal haplotypes for each family by performing targeted linked-read sequencing of their high molecular weight DNA, respectively. Then, we integrated the maternal haplotypes and the targeted sequencing results of maternal plasma DNA to infer the fetal haplotype and the DMD gene variant status. The fetal genotypes were further validated by using chorionic villus sampling.Results: The method of directly resolving maternal haplotype through targeted linked-read sequencing was smoothly performed in 12 participated families, but one failed (F11). The predicted variant status of 12 fetuses was correct, which had been confirmed by invasive prenatal diagnosis.Conclusion: Direct haplotyping of NIPD based on linked-read sequencing for DMD is accurate. [ABSTRACT FROM AUTHOR]

To observe the effect of Cai's Neiyi Prescription (CNYP) on the apoptosis and inflammation in endometrial stromal cells with endometriosis (EM) both in vivo and in vitro, EM model rats and endometrial stromal cells were treated with CNYP and the level of USP10, p‐ERK1/2, ERK1/2, and apoptosis‐related protein as well as the levels of proinflammatory factors were measured by Western blotting and ELISA, respectively. Rats with surgically induced EM showed increased USP10 expression and ERK/2 activation. Intragastric administration of CNYP granule significantly inhibited EM‐induced ERK1/2 activation and expression of USP10 and Bcl‐2, but increased the expression of Bax and Caspase‐7 in EM‐induced rats. CNYP granule administration also inhibited EM‐induced inflammation in rats. Moreover, the ectopic endometrial stromal cells isolated from EM patients demonstrated decreased ERK1/2 activation and expression of USP10 and Bcl‐2 and increased expression of Bax and Caspase‐7 after cultured in DMEM containing CNYP‐medicated rat serum, which were reversed by USP10 overexpression and were enhanced by USP10 siRNA. USP10 overexpression also inhibited while USP10 siRNA enhanced the CNYP‐induced inhibition of inflammation in ectopic endometrial stromal cells. Taken together, our results suggest that CNYP granule promotes apoptosis and inhibits inflammation in endometrial stromal cells with EM through inhibiting USP10. [ABSTRACT FROM AUTHOR]

An attitude algorithm is used by a given magnetic and inertial measurement unit (MIMU) for weight fusion of the outputs of gyroscope and the outputs of the subunit constructed by accelerometer and magnetometer for attitude calculation of a rigid body. It has been proved that the weight assigned to the outputs of gyroscope determines the overall performances of attitude algorithm. A new weight adaptive regulation method based on Kalman filter and hidden Markov model is proposed, and then a new attitude algorithm is constructed by the integration of that method with recursive quaternion estimation algorithm. The authors' attitude algorithm is compared with some other related attitude algorithms in their experiments. With the outputs of the sensors in MTi as the inputs of the new attitude algorithm, the maximum attitude estimation errors in response to three‐dimensional random movements and the changes of their amplitudes are 2.85° and 6.82°, respectively, and the Allan variance of attitude drift in response to motionless conditions is 2.1×10−4°. Other attitude algorithms cannot simultaneously achieve similar dynamic and similar static performances comparing to their attitude algorithm. The results validate the overall performance improvement of their attitude algorithm. [ABSTRACT FROM AUTHOR]

Abstract: This was a randomized, double‐blind, crossover, clinical‐end‐point pilot study examining the hypothesis that inhaled fluticasone propionate decreases exhaled nitric oxide (eNO) concentrations within a week of beginning treatment and shows evidence of dose separation across the marketed dose range. Subjects had a ≥6‐month history of asthma and screening eNO ≥60 parts per billion. At the start of each treatment period, eNO was ≥55 parts per billion, and forced expiratory volume in 1 second was ≥50% predicted. Subjects attended a clinic visit daily on consecutive mornings during each of 3 1‐week treatment periods to measure eNO and receive once‐daily doses of 100/50, 250/50, or 500/50 fluticasone propionate/salmeterol combination product (Advair® Diskus). Daily eNO value recorded was the highest of 3 measurements; 1 inhalation of treatment was then administered. Procedures were repeated for 3 treatment cycles, separated by 14‐day minimum washouts. A total of 105 subjects were screened; 22 were randomized; and 17 completed all treatments. Mean percentage eNO decrease (standard deviation) from day 1 baseline for each treatment period was 36.6 (±18.7), 45.3 (±16.5), and 54.6 (±12.5) with Advair® 100/50, 250/50, and 500/50, respectively. Mean percentage decrease in eNO across each treatment (dose) was modeled using a mixed‐model ANOVA. Although the overall treatment was significant (P = .0015), because of the relatively small sample size and within‐subject variability, only the 100/50 vs 500/50 (P = .0003) and 250/50 vs 500/50 (P = .047) treatments were significantly different. [ABSTRACT FROM AUTHOR]

ABSTRACT A thermotropic acetylene-terminated liquid-crystal monomer, 2-methyl-1,4-phenylene bis(4-ethynylbenzoate) (MPBE), was prepared and used as a modification composition to react and cocure with a silicon-containing arylacetylene (PSA) oligomer for improving PSA resin. The curing behavior of the PSA-MPBE resins were characterized by differential scanning calorimetry and Fourier transform infrared spectroscopy. The microstructure and morphology of the PSA-MPBE resins were investigated by scanning electron microscopy (SEM) and transmission electron microscopy. Their dynamic mechanical properties and thermostability were measured by dynamic mechanical analysis (DMA) and thermogravimetric analysis. The results indicate that the thermotropic acetylene-terminated liquid-crystal monomer melted into a schlieren texture. MPBE and PSA could copolymerize to fix the mesogenic domain in the crosslinked network and form a homogeneous-phase sea-island structure, which improved the rigidity and toughness of the materials. DMA showed that the storage modulus of the PSA-MPBE resins increased by about 400 MPa compared to the those of the pure components. The SEM experiments showed a noticeable change in the morphology, from a typical brittle fracture for the pure PSA to microplastic deformation behavior for the PSA-MPBE resins. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45141. [ABSTRACT FROM AUTHOR]

Aim: Metformin plays an important role in the inhibition of cancer cell growth and prolongs remission durations. It reverses progestin-resistance in endometrial cancer cells by downregulating glyoxalase I (GloI) expression. This study aimed to investigate the effect of metformin on endometrial cancer cell chemotherapeutic sensitivity and explore the underlying molecular mechanisms. Material and Methods: MTT assay was performed to determine the rate of cell death after cisplatin and paclitaxel with or without metformin. Western blot was carried out to analyze GloI expression. SiRNA-targeting of GloI was used to knockdown GloI expression before further treatment with chemotherapeutic agents to examine the effect of GloI downregulation on chemotherapy-induced cell killing. In addition, plasmid transfection was used to overexpress GloI and determine whether high GloI levels blocked metformin-enhanced cell sensitivity to chemotherapy. PCR was used to analyze the efficiency of RNA interference and plasmid transfection. Results: The addition of metformin enhanced the sensitivity of endometrial cells to cisplatin and paclitaxel, which was associated with reduced levels of GloI expression. Moreover, low-dose chemotherapeutic drugs alone could not significantly reduce GloI expression, whereas the addition of metformin potently downregulated GloI protein levels. Cisplatin and paclitaxel markedly inhibited the proliferative ability of GloI-depleted endometrial cancer cells. However, the overexpression of GloI abolished the effect of metformin-enhanced cell sensitivity to chemotherapeutic drugs. Conclusion: Metformin enhances the rate of cell-killing induced by chemotherapeutic agents by repressing GloI expression. [ABSTRACT FROM AUTHOR]

Silicon‐containing arylacetylene resins (PSAs) are promising thermal stability polymers for many applications. However, the controllability of curing reaction limited their application because of the high curing temperature and enthalpy. In this study, Materials Genome Initiative was utilized to screen out a target monomer, 2,7‐diethynyl‐9H‐fluorene (DEF), for design of new PSAs with low curing temperature and enthalpy. After incorporation of DEF, the obtained silicon‐containing fluorenylacetylene resins (PSA‐VBF) could be cured at a lower temperature of 149.2 °C with lower enthalpy (239.8 J g−1) than the reported PSA‐V (190.0 °C, 368.3 J g−1). Moreover, the thermal curing behavior and mechanism were investigated by differential scanning calorimetry, Fourier transform infrared, and pyrolysis‐gas chromatography–mass spectrometry. The results revealed that with the increased of DEF, the curing reaction of PSA‐VBF became dominated by Diels–Alder reaction. And the formed aromatic fused rings endowed the cured PSA‐VBF with excellent thermal stability, which were proved by thermogravimetric analysis results that the temperature at 5% weight loss (Td5) of the cured copolymers ranged from 630 to 639 °C, and the char yield at 1000 °C was above 90%. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48262. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Comment on Metformin sensitizes endometrial cancer cells to chemotherapy by repressing glyoxalase I expression" in the February 2013 issue.