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Geopolymer concrete (GPC) is regarded as a more environmentally friendly construction material compared to conventional cement concrete, and its exceptional environmental capabilities are highly favored by the contemporary construction sector. Studying the mechanical properties of GPC upon exposure to elevated temperatures is a crucial aspect of evaluating structural damage and enhancing fire safety measures. Nevertheless, properly predicting the compressive performance of GPC upon exposure to high temperatures remains a formidable task. This study employs various machine learning techniques, such as single models, integrated models, neural network models, and hybrid models, to predict the compressive strength of GPC from room temperature to 1000°C. The results of each model are summarized, and the significant factors influencing compressive strength are analyzed to evaluate the thermal behavior of GPC. These findings offer recommendations for future in‐depth machine learning applications in the GPC field. The K‐fold cross‐validation shows that the hybrid model genetic algorithm–random forest has the highest prediction accuracy, while the single model performs the worst. Other models also provide favorable prediction results. The feature importance analysis revealed that the compressive strength of GPC is primarily influenced by heating temperature (HT) and hydroxide ion concentration, with fly ash and ground granulated blast furnace slag content being secondary factors. The partial dependence plot‐2D analysis indicates that as HTs increase, the influence of other variables on GPC compressive strength decreases significantly. These findings can inform the design of GPC mixing ratios for high‐temperature exposure. The machine learning technique proposed in this study accurately predicts GPC compressive strength across various temperatures, reducing experimental time and costs while promoting the GPC sector. [ABSTRACT FROM AUTHOR]

Lead ion (Pb2+) is a high‐hazardously heavy metal ion in surroundings that even ppb level can cause mental decline and behavioral difficulties especially in children. However, the recognition and detection of Pb2+ are still challenging. Here, a high selective and ultra‐sensitive chemiluminescence (CL) method was established based on the substitution mechanism between Pb2+ and the metal–organic framework – Cu‐MOF‐74. Pb2+ can specifically substitute Cu active sites in Cu‐MOF‐74 and released Cu sites, strongly amplifying the CL emission of the luminol‐hydrogen peroxide (H2O2) system. A linear response for Pb2+ detection in the range of 0.5–50 nM with a detection limit of 0.3 nM was realized. Moreover, the proposed method was successfully implemented on a paper‐based analytical device with favorable fabrication and operational features for Pb2+ determination in water samples. It offers a new strategy to design high selective and sensitive sensors for the heavy metal ions monitoring. [ABSTRACT FROM AUTHOR]

Concealed information test (CIT) has been utilized for long to perform single measurements. The combination of multiple measures outperforms single measures because of the diverse cognitive processes they reflect and the reduction in random errors facilitated by multiple measures. To further explore the performance of the CIT with multiple measurements, 57 participants were recruited and randomly assigned into guilty and innocent groups. Subsequently, simultaneously recorded reaction time (RT), skin conductance responses (SCRs), heart rate (HR), and neuroimaging data were collected from functional near‐infrared spectroscopy (fNIRS) to detect participants' concealed information in a standard CIT. The results demonstrated that all indicators including RT (area under the curve (AUC) = 0.87), SCRs (AUC = 0.79), HR (AUC = 0.78), and fNIRS (channel 8, AUC = 0.85) could differentiate guilty and innocent groups. Importantly, the use of multiple indicators achieved higher detection efficiency (AUC = 0.96) compared to the use of any single indicator. These results illustrate the effectiveness and feasibility of integrating multiple indicators for concealed information detection in CIT. [ABSTRACT FROM AUTHOR]

The objective of this study was to elucidate whether paeoniflorin (PF) exerted an effect on cisplatin‐induced spiral ganglion neuron (SGN) damage, with special attention given to the role of PINK1/BAD pathway in this process. Middle cochlear turn culture and C57BL/6 mice were utilized to identify the character of PF in vitro and in vivo. We found that cisplatin treatment led to SGN damage, in which reactive oxygen species (ROS) generation increased, PINK1 expression decreased, BAD accumulation on mitochondria raised and mitochondrial apoptotic pathway activated. Conversely, we demonstrated that PF pre‐treatment obviously mitigated cisplatin‐induced SGN damage. Mechanistic studies showed that PF could reduce ROS levels, increase PINK1 expression, decrease the BAD accumulation on mitochondria and, thus, alleviate the activated mitochondrial apoptosis in SGNs caused by cisplatin. Overall, the findings from this work reveal the important role of PF and provide another strategy against cisplatin‐induced ototoxicity. [ABSTRACT FROM AUTHOR]

Retinoic acid‐inducible gene I (RIG‐I) is a critical RNA virus sensor that initiates antiviral immune response through K63‐linked ubiquitination. In this study, we demonstrated USP14, a deubiquitinating enzyme, as a negative regulator in antiviral responses by directly deubiquitinating K63‐linked RIG‐I. USP14 knockdown significantly enhanced RIG‐I‐triggered type I IFN signaling and inhibited vesicular stomatitis virus (VSV) replication both in mouse peritoneal macrophages and THP1 cells. USP14 overexpression in HeLa cells attenuated RIG‐I‐triggered IFN‐β expression and promoted VSV replication. Besides, USP14‐specific inhibitor, IU1, increased RIG‐I‐mediated type I IFN production and antiviral responses in vitro and in vivo. In addition, USP14 could interact with RIG‐I and remove RIG‐I K63‐linked polyubiquitination chains. This article is the first to report that USP14 acts as a negative regulator in antiviral response through deubiquitinating K63‐linked RIG‐I. These findings provide insights into a potential new therapy targeting USP14 for RNA virus‐related diseases. Triggered by RNA virus, USP14 acts as a negative regulator through deubiquitinating K63‐linked RIG‐I in innate immune response. These findings provide insights into a potential new therapy targeting USP14 for RNA virus related diseases. [ABSTRACT FROM AUTHOR]

Serine/threonine kinase 33 (STK33), a member of the calcium/calmodulin‐dependent kinase (CAMK), plays vital roles in a wide spectrum of cell processes. The present study was designed to investigate whether STK33 expressed in the mammalian cochlea and, if so, what effect STK33 exerted on aminoglycoside‐induced ototoxicity in House Ear Institute‐Organ of Corti 1 (HEI‐OC1) cells. Immunofluorescence staining and western blotting were performed to investigate STK33 expression in cochlear hair cells (HCs) and HEI‐OC1 cells with or without gentamicin treatment. CCK8, flow cytometry, immunofluorescence staining and western blotting were employed to detect the effects of STK33 knockdown, and/or U0126, and/or N‐acetyl‐L‐cysteine (NAC) on the sensitivity to gentamicin‐induced ototoxicity in HEI‐OC1 cells. We found that STK33 was expressed in both mice cochlear HCs and HEI‐OC1 cells, and the expression of STK33 was significantly decreased in cochlear HCs and HEI‐OC1 cells after gentamicin exposure. STK33 knockdown resulted in an increase in the cleaved caspase‐3 and Bax expressions as well as cell apoptosis after gentamicin damage in HEI‐OC1 cells. Mechanistic studies revealed that knockdown of STK33 led to activated mitochondrial apoptosis pathway as well as augmented reactive oxygen species (ROS) accumulation after gentamicin damage. Moreover, STK33 was involved in extracellular signal‐regulated kinase 1/2 pathway in primary culture of HCs and HEI‐OC1 cells in response to gentamicin insult. The findings from this work indicate that STK33 decreases the sensitivity to the apoptosis dependent on mitochondrial apoptotic pathway by regulating ROS generation after gentamicin treatment, which provides a new potential target for protection from the aminoglycoside‐induced ototoxicity. [ABSTRACT FROM AUTHOR]

ABSTRACT Polycarbonate (PC) is an engineering thermoplastic with excellent insulation and mechanical properties. However, the low thermal conductivity restricted its application in electronic devices. Hexagonal boron nitride ( h-BN) microparticle, a promising material with high thermal conductivity, was functionalized with cationic polyacrylamide (CPAM) and introduced into PC matrix to improve the thermal conductivity. SEM and XRD analysis showed that the modified BN (CBN) particles oriented and formed thermal conductive pathways within PC matrix. The formation of large-area oriented CBN significantly improved the thermal conductivity and thermal stability of composites. At 20 wt % CBN loading, the thermal conductivity of 0.7341 Wm−1 K−1 and the temperature for 5% weight loss ( T5) of 498.6 °C were obtained, which was 3.1 times and 77 °C higher than that of pure PC, respectively. Furthermore, outstanding electrical insulation property of matrix was retained in the composites. These results revealed that PC/CBN composite was a promising material for thermal management and electrical enclosure. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44978. [ABSTRACT FROM AUTHOR]

Combining the excellent mechanical strengths of polyamide 6 (PA6) with the low water absorption of poly(butylene terephthalate) (PBT) was supposed to be a feasible way to prepare a high comprehensive performance material. However, the poor compatibility between PA6 and PBT resulted in low-notched impact strength of PA6/PBT blends. Poly( n-butyl acrylate)/poly(methyl methacrylate- co-methacrylic acid) (PBMMA), a core-shell structured modifier with controlled particle sizes, was prepared by seed emulsion polymerization and confirmed by Transmission electron microscope (TEM). The PBMMA particles as toughening modifier and compatilizer were employed to toughen PA6/PBT blends. The notched impact strength of the PA6/PBT blends was significantly increased and the water absorption was reduced with the addition of PBMMA particles. With 23.0 wt% modifier loading, the notched impact strength of the blends was 25.66 kJ/m2, which was 4.04 times higher than that of pure PA6/PBT. Meanwhile, the water absorption of the blends was only 1.3%, dropping 53.6% compared with pure PA6 and reducing by 26.6% than PA6/PBT. Scanning electron microscope results showed that the PBMMA particles were dispersed in the PA6/PBT blends homogeneously, and the toughening mechanism was the cavitation of rubber particles and shear yielding of the matrix. Thermo-gravimetric analysis analysis demonstrated that the compatibility between PA6 and PBT was improved with the addition of core-shell PBMMA particles. The core-shell particles could be used as an effective modifier to achieve the high toughness and low water absorption for PA6/PBT blends. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Antimony-doped CeO2-WO3/TiO2 catalysts were prepared by a conventional ultrasonic-assisted impregnation method and employed for selective catalytic reduction of NO x with NH3 at low temperature. Both experimental work and theoretical studies were employed to elucidate the effect of the antimony on promoting the CeO2-WO3/TiO2 catalyst. The catalytic activity of CeO2-WO3/TiO2 was largely improved after the addition of antimony oxide. It was found that antimony doping reduced the crystal size and strengthened the synergistic effect between the metal cations, which resulted in a favorable catalyst surface status with abundant active surface oxygen, Brønsted acid sites, and effective electron transfer. Both in situ diffuse reflectance infrared Fourier transform analysis and DFT calculation results revealed that the ammonia and NO x desorption behavior over the catalyst surface were considerably different. For the ammonia species, rather large amounts of the active NH4+ and NH3 species anchored on the surface of the Sb-doped CeO2-WO3/TiO2. In view of the NO x species, the amount of nonactive bidentate nitrate species was largely reduced and the amount of active gaseous NO2 species was clearly enhanced, which lowered the activation energy of the catalytic process and gave rise to the elevated low-temperature NH3 selective catalytic reduction activity. All these preferable properties resulted in the elevated de-NO x activity of the Sb-doped CeO2-WO3/TiO2 catalyst. [ABSTRACT FROM AUTHOR]

Antimony-doped CeO2-WO3/TiO2 catalysts were prepared by a conventional ultrasonic-assisted impregnation method and employed for selective catalytic reduction of NO x with NH3 at low temperature. Both experimental work and theoretical studies were employed to elucidate the effect of the antimony on promoting the CeO2-WO3/TiO2 catalyst. The catalytic activity of CeO2-WO3/TiO2 was largely improved after the addition of antimony oxide. It was found that antimony doping reduced the crystal size and strengthened the synergistic effect between the metal cations, which resulted in a favorable catalyst surface status with abundant active surface oxygen, Brønsted acid sites, and effective electron transfer. Both in situ diffuse reflectance infrared Fourier transform analysis and DFT calculation results revealed that the ammonia and NO x desorption behavior over the catalyst surface were considerably different. For the ammonia species, rather large amounts of the active NH4+ and NH3 species anchored on the surface of the Sb-doped CeO2-WO3/TiO2. In view of the NO x species, the amount of nonactive bidentate nitrate species was largely reduced and the amount of active gaseous NO2 species was clearly enhanced, which lowered the activation energy of the catalytic process and gave rise to the elevated low-temperature NH3 selective catalytic reduction activity. All these preferable properties resulted in the elevated de-NO x activity of the Sb-doped CeO2-WO3/TiO2 catalyst. [ABSTRACT FROM AUTHOR]