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Chronic cerebral hypoperfusion (CCH) has been confirmed as one of the pathogenesis underlying vascular cognitive impairment. A series of pathological changes, including inflammation, oxidative stress, and apoptosis, are involved in this pathophysiology and contribute to cognitive impairment and neuropathological alterations. The traditional Chinese medicine (TCM) of Buqi Huoxue Tongnao (BQHXTN) prescription possesses a remarkable clinical efficacy for treating patients with CCH, but still lacks a scientific foundation for its pharmacological mechanisms. To investigate the role and underlying mechanism of the effects of BQHXTN on CCH both in vitro and in vivo. In this study, we established a two-vessel occlusion (2-VO) induced CCH model in Sprague-Dawley rats, an oxygen-glucose deprivation model in BV2 cells, and a steatosis cell model in L02 cells to reveal the underlying mechanisms of BQHXTN by behavioral test, histopathological analysis and the detection of pro-inflammatory cytokine, apoptotic factors and reactive oxide species. Donepezil hydrochloride and Buyang Huanwu decoction were used as positive drugs. Compared with the 2-VO group, BQHXTN treatment at three doses significantly enhanced the memory and learning abilities in the Y-maze and novel object recognition tests. The hematoxylin-eosin staining indicated that BQHXTN protected against hippocampal injury induced by CCH. Of note, in both in vivo and in vitro experiments, BQHXTN prominently inhibited the production of IL-1β, TNF-α, cleaved-caspase 3, and iNOS by regulating the PI3K/AKT pathway, consequently exerting anti-inflammatory, anti-apoptotic, and antioxidant effects. Moreover, it provided the first initial evidence that BQHXTN treatment mitigated dyslipidemia by increasing the LXRα/CYP7A1 expression, thereby delaying the neuropathological process. In summary, these findings firstly revealed the pharmacodynamics and mechanism of BQHXTN, that is, BQHXTN could alleviate cognitive impairment, neuropathological alterations and dyslipidemia in CCH rats by activating PI3K/AKT and LXRα/CYP7A1 signaling pathways, as well as providing a TCM treatment strategy for CCH. [Display omitted] [ABSTRACT FROM AUTHOR]

Geopolymer with Si/Al ratios from 2 to 4 were prepared by adding different contents of fused silica into geopolymer matrix. Effects of Si/Al ratios on the structure, mechanical properties and chemical stability in air of the obtained geopolymer were systematically investigated. The results showed that all the geopolymer samples were XRD amorphous. Geopolymer with Si/Al ratios of 2 and 2.5 showed similar structure and property and they were classed as KGP-I; and geopolymer with Si/Al ratios of 3, 3.5 and 4 were similar and they were class as KGP-II. In alkaline solution, reactivity of fused silica were higher than that of metakaolin, resulting in higher content of both residual metakaolin and free alkaline cation in KGP-II than in KGP-I. Fused silica partially reacted with the alkaline solution in KGP-II indicating chemical interfacial bonding between silica and binder phase. With the increase in Si/Al ratios, KGP-II especially for geopolymer with Si/Al of 4 showed much higher mechanical properties than KGP-I due to the increased Si-O-Si bonds and residual silica as reinforcement. However, KGP-II showed worse chemical stability in air than KGP-I, with the presence of efflorescence on the surface, which was attributed to their higher residual free K + . [ABSTRACT FROM AUTHOR]

Highlights: [•] EIS was employed for the first time employed to determine fenvalerate. [•] Pre-treatment for the detection is simple in operation with this technique. [•] This method is label-free with high sensitivity and selectivity, rapidity and low cost. [ABSTRACT FROM AUTHOR]

Highlights: [•] PoPD was for the first time applied to form composite with metal oxide. [•] PoPD/MnO2 was synthesized by a one-step co-precipitation. [•] PoPD/MnO2 composite was for the first time applied as electrode materials in supercapacitor. [Copyright &y& Elsevier]

Highlights: [•] We first found that AST had better anti-lung fibrosis function than dexamethasone. [•] Anti-proliferation and pro-apoptosis effects might be by up-regulation of p53. [•] We establish astaxanthin as a potential drug candidate for lung fibrosis. [ABSTRACT FROM AUTHOR]

Abstract: For the first time, poly-o-phenylenediamine (PoPD) bulk material was electrochemically synthesized using an electrochemical method. Sodium dodecyl sulfate (SDS) was added to o-phenylenediamine (oPD) solution and PoPD with different morphologies were obtained. The as-prepared materials were applied as the electrode materials in supercapacitors. The specific capacitance (SC) of the resultant PoPD was determined to be 106.4Fg−1 in 1molL−1 KNO3 electrolyte from CV test. The electrochemical stability of PoPD electrode was investigated by charging and discharging the electrode for 1000 times in the potential range of −0.2 to 0.6V versus SCE at the current density of 500mAg−1. The electrode exhibits a good cycling stability, retaining up to 82% of its initial specific capacitance at 1000th cycle. This novel technique enables PoPD non-film material for supercapacitor application. [Copyright &y& Elsevier]

Abstract Based on conventional ion exchange method from zeolite materials, we herein report a facile synthetic procedure to prepare monoclinic celsian ceramics through thermal treatment of ion-exchanged 3D printing geopolymer precursors. In this contribution, both ion exchange process and thermal evolution of celsian precursors were systematically investigated. The results proved 3D printing Na- and K- based geopolymer were ideal precursors with low residual Na+ content (0.10 meq/g) and K+ content (0.05 meq/g) and translated into monoclinic celsian after being heated at 1400 °C. With increasing Sr2+ doping concentration from 20% (mole ratio) to 30% (mole ratio), more significant phase transition results (hexagonal → monoclinic) were observed. All 3D printing geopolymer precursors kept fine integrity and stable 3D structure upon ion exchange process and heating, indicating the combination of geopolymer technique and 3D printing opens up a versatile and robust way to yield monoclinic celsian ceramics and related components of complex shapes. [ABSTRACT FROM AUTHOR]

A concise synthetic approach to the marine natural product (+)-aureol has been achieved from readily available starting materials using obviously fewer steps in comparison to the related report in literature (6 steps versus 12 steps from (+)-sclareolide). Key steps of this protocol include a boron trifluoride-catalyzed domino 1,2-H and 1,2-methyl shifts and a nickel(II)-catalyzed cross-coupling reaction between an alkyl iodide and an aryl Grignard reagent. [ABSTRACT FROM AUTHOR]

Abstract: An electrochemical sensor based on a self-made electrode from recordable CDs was developed for the non-enzymatic detection of glucose by chronoamperometry. We discussed the amperometric current response of glucose with the change of potential, pH and electrode area, and determined the optimum detection conditions. The current response measurements were performed in a phosphate buffered solution (pH 6.5) with a potential of −0.50V, and presented a linearity over the range of 0.5–13mmol/L (r =0.996). The experimental results of the designed sensor demonstrate that this method has merits such as simple operation, low cost and rapid responses. The results of detecting glucose in blood samples were satisfactory. [Copyright &y& Elsevier]

Abstract: In this paper crystallization kinetics of potassium-based geopolymer (Si/Al=2.5, denoted as KG2.5) upon heating are investigated by differential thermal analysis (DTA) under non-isothermal conditions at various heating rates. From 35 to 700°C KG2.5 shows a significant weight loss due to both evaporation of free water and condensation of hydroxyl groups. Crystallization of KG2.5 starts at a low temperature of ∼960°C according to XRD and DTA analysis. KG2.5 also exhibits a low onset temperature of viscous sintering stage and on heating to 950°C the sintering is completed. In the DTA graphs, the exothermic peaks which are caused by leucite crystallization shift to higher temperatures with increasing heating rate. The activation energy value of crystallization for leucite is found to be 455.9kJ/mol and the corresponding Avarami constant is 3.89 indicating the three-dimensional crystal growth mechanism. [ABSTRACT FROM AUTHOR]

Abstract: The thermal evolution of cesium-substituted potassium-based geopolymer ((K1−x Cs x )2O·Al2O3·5SiO2·11H2O, x =0, 0.1, 0.2, 0.3, and 0.4) on heating is studied by a variety of techniques. Phase compositions and thermal expansion behaviors of the ceramics derived from the geopolymer are characterized. All of the geopolymer specimens with or without cesium substitution exhibit similar thermal evolution trends. Major weight losses before 600°C from all the geopolymer specimens are observed and are resulted from evaporation of free water and hydroxyl groups. Thermal shrinkage of these specimens can be divided into four stages, i.e. structural resilience, dehydration, dehydroxylation and sintering, according to the dilatometer results. For these specimens, significant difference is observed in the viscous sintering stage and the effect of cesium is to reduce the thermal shrinkage in this stage due to the increased matrix viscosity. In the ceramics derived from geopolymer, the amount of stabilized leucite increases with the amount of cesium and with 20% cesium substitution leucite is fully stabilized in cubic phase. [ABSTRACT FROM AUTHOR]

Abstract: Unidirectional carbon fiber reinforced geopolymer composite was prepared by ultrasonic-assisted slurry infiltration method and heat treated at 1100°C. Then it was impregnated with Sol-SiO2 to seal the cracks and pores formed during heat treatment. The ambient strength of composite after impregnation was enhanced by 35.6% due to the increase relative density from the starting 79% to 93.6%. Composites both before and after impregnation fractured in a non-brittle manner at both ambient and high temperatures. Over an elevated temperature range from 700 to 900°C, the strength of the two composites showed anomalous gains and reached their maximum values at 900°C, 322.1 and 425.1MPa, respectively. These values were 19.8% and 16.8% higher than their ambient ones. When the temperature was further increased to 1100°C, the impregnated composite showed superior high-temperature properties, which was attributed to the improved fiber integrity due to the Sol-SiO2 sealing effect. [ABSTRACT FROM AUTHOR]

Abstract: We propose a novel structure of the sensor head for optical current transducer (OCT), which consists of a bulk magneto-optic glass with graded index (GRIN) and a ferromagnetic ring acting as magnetic field concentrator. According to the transmission properties of the light in GRIN medium, under certain conditions the light beam propagates along a periodical curved track inside the sensor head and hence is unable to achieve the medium–air interface. Hence, this sensor head can effectively avoid the system error caused by reflection phase shift in the traditional bulk glass optical current transducer (BGOCT). Moreover, the track equation of the light beam, the effective optical path, and the effective range of the incident angle are analyzed and numerically simulated. The results show that the sensitivity of the proposed sensor head can be further improved by appropriately increasing the incident angle and the refractive index difference as well as coating a polarization-maintaining reflective film on the surface of the magneto-optic glass. [Copyright &y& Elsevier]

Abstract Brazing and soldering following pre-metallization were employed to obtain reliable ZrO 2 /Sn-Ti/ZrO 2 joints. Both the metallization and brazing depend on the wettability of ZrO 2 by Sn-Ti alloys. The interfacial microstructure of joints was analyzed by SEM, XRD and TEM, and the shear strength of joints was evaluated. Good brazed joints and fully covered metallization layers, leading to good soldered joints, were obtained by the Sn-4Ti and Sn-8Ti alloys, while unsatisfactory results were obtained with Sn-1Ti and Sn-2Ti alloys owing to their limited wettability on ZrO 2. Both kinds of ZrO 2 /Sn-Ti/ZrO 2 joints possessed a β-Sn matrix with Ti 6 Sn 5 and Ti 2 O 3 interfacial layers. A higher Ti concentration per unit area induced the formation of a Ti 11.31 Sn 3 O 10 layer along with the reduction of the Ti 2 O 3 layer thickness at the interface in the soldered joints. All the joints exhibited a similar shear strength of 22 ∼ 28 MPa and fractured through the β-Sn matrix. [ABSTRACT FROM AUTHOR]

In this work, we report the fabrication of geopolymer materials containing different amounts of reduced graphene oxide loaded on zinc oxide (rGO@ZnO/GP) to be used as efficient photocatalysts for the degradation of methylene blue (MB). The synergistic effects of adsorption and photodegradation resulted in a 92.56% removal efficiency of MB within 30 min by a geopolymer containing 56%rGO@ZnO (56%rGO@ZnO/GP). The results showed that the geopolymer matrix provided a reusable carrier for rGO@ZnO, and the presence of rGO could promote the migration of photogenerated electrons and hinder the recombination of charges, thereby enhancing the photocatalytic activity. The best performing material (56%rGO@ZnO/GP) was also used to 3D print a scaffold using Direct Ink Writing technology. The 3D printed 56%rGO@ZnO/GP was also an efficient photocatalyst for the degradation of MB, and the use of a structured catalyst facilitates the recovery of the active material. This work can provide a way for preparing efficient and environmentally friendly photocatalysts. [Display omitted] • Novel rGO@ZnO/GP photocatalysts were designed. • The photocatalytic activity of rGO@ZnO/GP was tested and the photocatalytic mechanism was investigated. • rGO@ZnO/GP was able to decompose MB through the synergistic effect of adsorption and photocatalysis. • The 3D-printed rGO@ZnO/GP could be recycling and reuse. [ABSTRACT FROM AUTHOR]

[Display omitted] • PM2.5 greatly deteriorated the fibrosis process in pre-existing pulmonary fibrosis via ferroptosis. • HO-1-mediated mitochondrial dysfunction was related to ferroptosis and exacerbation of pulmonary fibrosis induced by PM2.5. • NCOA4-mediated ferritinophagy participated in the ferroptosis and exacerbation of pulmonary fibrosis induced by PM2.5. Fine particulate matter (PM2.5) has been widely reported to contribute to the pathogenesis of pulmonary diseases. The direct hazardous effect of PM2.5 on the respiratory system at high concentrations in vitro and in vivo have been well identified. However, its effect on the pre-existing respiratory diseases of patients at environment-related concentrations remains unclear. Diesel exhaust PM2.5 as a primary representative of ambient PM2.5 fine particles were used to investigated the effect of PM2.5 on the fibrosis progression of existing pulmonary fibrosis disease models. This study reported that PM2.5 could result in the enhanced sensitivity to fibrotic response, which may be ascribed to ferroptosis induced by PM2.5 in damaged lung areas. Proteomic analysis revealed that the upregulation of HO-1 as a key mechanism in the ferroptosis and exacerbation of pulmonary fibrosis induced by PM2.5. As a result, HO-1 degraded heme-containing protein and released iron in fibrotic cells, leading to generation of mitochondrial ROS and impaired mitochondrial function. Transmission electron microscopic assay verified that PM2.5 entered the mitochondria of fibrotic cells and was accompanied by significant mitochondrial morphological changes characterized by increased mitochondrial membrane density and reduced mitochondrial size. The HO-1 inhibitor zinc protoporphyrin and mitochondrion-targeted antioxidant Mito-TEMPO significantly attenuated PM2.5-induced ferroptosis and exacerbation of fibrosis. In addition, AMPK-ULK1 axis-triggered autophagy activation and NCOA4-mediated degradation of ferritin by autophagy were found to be related to the PM2.5-induced ferroptosis of fibrotic cells. As evidenced by the inhibition of autophagy with 3-methyladenine or AMPK inhibitor, NCOA4 knockdown decreased intracellular iron accumulation and lipid peroxidation, thereby relieving PM2.5-induced epithelial–mesenchymal transition and cell death in fibrotic cells. Overall, this study provided experimental support for the idea that PM2.5 greatly deteriorates fibrosis process in pre-existing pulmonary fibrosis, and HO-1-mediated mitochondrial dysfunction and NCOA4-mediated ferritinophagy are jointly required for the PM2.5-induced ferroptosis and enhanced fibrosis effects. [ABSTRACT FROM AUTHOR]

A new method for phase-shifted fiber Bragg grating (PS-FBG) inscription in single mode fiber by fusion splicing technique and femtosecond laser is presented. The PS-FBG is produced by exposing the fusion spliced fiber with femtosecond laser through a uniform phase mask. The transmission spectrum of the PS-FBG shows a nonlinear red shift during the inscription process, and two or three main dips can be observed due to the formation of one or two FBG-based Fabry–Pérot structures by controlling the exposure intensity and time of the laser. For a peak power density of 4.8×10 13 W/cm 2 , the induced refractive index modulation can reach to 6.3×10 −4 in the fiber without sensitization. The PS-FBG's temperature, strain and pressure characteristics are also experimentally studied. These PS-FBGs can be potentially used for multiple wavelength fiber lasers, filters and optical fiber sensors. [ABSTRACT FROM AUTHOR]

Abstract: Unidirectional carbon fiber reinforced geopolymer composite (Cuf/geopolymer) is prepared by a simple ultrasonic-assisted slurry infiltration method, and then heat treated at elevated temperatures. Effects of high-temperature heat treatment on the microstructure and mechanical properties of the composites are studied. Mechanical properties and fracture behavior are correlated with their microstructure evolution including fiber/matrix interface change. When the composites are heat treated in a temperature range from 1100 to 1300°C, it is found that mechanical properties can be greatly improved. For the composite heat treated at 1100°C, flexural strength, work of fracture and Young''s modulus reach their highest values increasing by 76%, 15% and 75%, respectively, relative to their original state before heat treatment. The property improvement can be attributed to the densified and crystallized matrix, and the enhanced fiber/matrix interface bonding based on the fine-integrity of carbon fibers. In contrast, for composite heat treated at 1400°C, the mechanical properties lower substantially and it tends to fracture in a very brittle manner owing to the seriously degraded carbon fibers together with matrix melting and crystal phases dissolve. [Copyright &y& Elsevier]