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In the photolithography process of integrated circuits （IC） manufacturing, it is desired that the photoresist resins have both smaller polydispersity index (PDI) and lower trace metal ion concentrations. The commercial environmentally stable chemical amplified photoresist (ESCAP) resins for 248 nm lithography are synthesized by free radical polymerization with PDI >1.5. Although using atom transfer radical polymerization (ATRP) can result in lower PDI, the potential of high metal ion contamination is a major concern, as the reaction initiators usually are copper‐containing compounds. In this study, copolymer of p‐acetoxy styrene and tert‐butyl acrylate [poly(AOST‐co‐TBA)] is synthesized via ATRP achieving PDI as low as 1.25. It is then purified by ion exchange with two different resins, IRC747 and A15, which are effective at removing Cu and other metal ions. This reduces the total metal ion concentration in the copolymer powder to <30 ppb with individual metal ion <6 ppb. This is the first reported ATRP synthesized ESCAP resin having both low PDI and metal ion concentrations suitable for 248 nm photoresist application. [ABSTRACT FROM AUTHOR]

A large area of coarse-grained saline soil is distributed in saline soil areas, and chlorine saline soil with a high salt content is a typical representative. The dynamic resilient modulus was accurately predicted using the California-bearing ratio (CBR) value to determine the relationship between the dynamic resilient modulus of coarse-grained chloride saline soil and its CBR value. Indoor dynamic triaxial tests and CBR tests were conducted to investigate the evolution of the dynamic resilient modulus (MR) and CBR of coarse-grained chlorine saline soil under the influence of the stress level, water content, and salt content. The test results showed that the dynamic resilient modulus increased with an increase in the confining pressure and bulk stress and decreased as the deviator stress increased; however, the CBR increased with an increase in the corresponding unit pressure. The higher the salt and water contents, the more obvious the influence of stress on the dynamic resilient modulus and CBR value. Under the same stress level, the decrease in the dynamic resilient modulus and CBR gradually increased with increasing salt and moisture content, and the effect of salt tended to be more significant than that of water. Based on the correlation between the dynamic resilient modulus and CBR revealed by the experiment, a more widely applicable model was selected from the existing theoretical models related to CBR for the regression analysis of the test data, and a prediction model of the dynamic resilient modulus based on the CBR value was proposed (MR = 21.06CBR0.52). This prediction model had a high correlation coefficient (R2 = 0.893) and could effectively predict the dynamic resilient modulus of coarse-grained chlorine saline soil using CBR values. The results provide a simple and reliable method for determining the design parameters of a coarse-grained saline soil subgrade. [ABSTRACT FROM AUTHOR]

Internal temperature distribution of the high-temperature proton exchange membrane fuel cell (HT-PEMFC) is affected by the cooling temperature, heat generation and reactant gas flow. Reasonable temperature control is helpful to improve the fuel cell performance and durability. In this work, a three-dimensional model that couples the reactant flows, species transport, heat transfer, charge transfer, and electrochemical reaction, was developed to simulate the HT-PEMFC operation. A solid mechanics model was established to analyze the stress distribution of the fuel cell. The polarization curves, distributions of temperature, membrane proton conductivity, current density and stress are investigated for different cooling surface temperature. Furthermore, the effect of assembly temperature on the stress of phosphoric acid-doped polybenzimidazole (PBI) membrane is discussed. Results reveals that the peak power density and uniformity of current density decrease with the increase of cooling surface temperature difference. The peak power density decreases by 9.14% when the temperature difference increases from 0 K to 40 K. The cooling surface temperature difference of less than 10 K and the voltage range in 0.5–0.7 V can achieve better current density uniformity and smaller current density change rate. In addition, the membrane in fuel cell has the highest stress, and increasing the assembly temperature is helpful to reduce the membrane stress. When the assembly temperature increases from 293.15 K to 343.15 K, the max and min compressive stresses in membrane in-plane decrease from 39.436 MPa to 31.416 MPa–24.934 MPa and 17.369 MPa at the temperature difference of 30 K, which decreases by 36.77% and 44.7%, respectively. • A 3-D thermal fluid model and solid mechanics model of HT-PEMFC are developed. • Clearing the effects of temperature difference on polarization curve and stress. • Current density is more uniform with a temperature difference <10 K. • Increasing the assembly temperature can reduce the ab-PBI membrane stress. [ABSTRACT FROM AUTHOR]

Sheet‐like ZSM‐5 has been regarded as a promising material for catalytic applications due to its diffusion superiority. However, it still remains a challenge to obtain a desirable sheet‐like morphology because of the complex synthesis process of zeolites. Here, a facile strategy for synthesizing sheet‐like ZSM‐5 is developed by only adding ethanol as zeolite growth modifier in the synthesis gel. It is thought that ethanol might be preferentially absorbed on the {010} surface of zeolite crystals, interact with the exposed silicon hydroxyl groups on the crystal {010} facet, and suppress the growth of b axis, resulting in the sheet‐like shape. Through finely tunning synthesis parameters, sheet‐like ZSM‐5 crystals with thin b‐axis thickness of 90 nm and different aspect ratios could be obtained. Owing to its shorter diffusion path and optimized acidity, sheet‐like ZSM‐5 exhibits better catalytic performance than conventional ZSM‐5 in the alkylation of benzene with ethanol. [ABSTRACT FROM AUTHOR]

• A HT-PEMFC is modeled to study the heat, mass and charge transfer. • Impacts of four different cooling temperature gradient directions are analyzed. • Local proton conductivity and current density increase with cooling temperature. • Case 4 achieves a better current density distribution. Non-uniform current density distribution can lead to localized hotspots, resulting in shortened lifespans of fuel cells. The temperature distributions on the bipolar plate cooling surface significantly influence various parameters within a fuel cell. This study develops a mathematical model for a high-temperature proton exchange membrane fuel cell (HT-PEMFC) to simulate its operation in four different directions of temperature gradient on the cooling surface. The distributions of membrane temperature, proton conductivity, oxygen concentration, activation loss, and current density were obtained to clarify the interaction mechanism between cooling surface temperature and these parameters in fuel cell. The results show that the membrane temperature and proton conductivity increase and the oxygen concentrations decrease with increasing cooling surface temperature. A lower temperature in the catalyst layer regions leads to a decrease in the current density. In particular, when the cooling surface temperature distribution is characterized by a temperature decrease in the upstream area with a high reactant concentration and an increase in the downstream area with a low reactant concentration, the fuel cell has an excellent current density uniformity, which reaches 92.61 % at a voltage of 0.6 V and a cooling surface temperature difference of 10 K. [ABSTRACT FROM AUTHOR]

• Pyrolytic graphite heat dissipation to reduce temperature differences in a PEMFC. • A HT-PEMFC heat balance model is developed to evaluate heat spreader feasibility. • 3-D simulations of single cell operation with heat spreader are conducted. • Temperature difference in the MEA can be less than 5 K with TPG heat dissipation. • TPG is better than thermal oil for HT-PEMFC heat dissipation. Good heat dissipation to reduce the inside temperature difference can help prolong the lifetime of high temperature proton exchange membrane fuel cells (HT-PEMFCs). This study presents a thermal management method based on a heat spreader composed of pyrolytic graphite and copper for a HT-PEMFC. First, the feasibility of using pyrolytic graphite for HT-PEMFC heat dissipation is evaluated using the heat balance model. Then, a three-dimensional single cell model is coupled with heat transfer, mass transfer and electrochemical reactions to simulate the HT-PEMFC operation with the heat spreader thermal dissipation. The model is used to investigate the effect of various heat spreader structures composed of two kinds of pyrolytic graphite and the operating voltage on the temperature distribution and current density distribution. Finally, the HT-PEMFC with this thermal management method is compared with oil cooling. The results show that the TPG (thermal pyrolytic graphite) provides better HT-PEMFC heat dissipation than the PGS (pyrolytic graphite sheet). The heat can be dissipated from both sides to further reduce the temperature difference in the membrane electrode assembly (MEA) by 64.7 % over that with single-side heat dissipation. In addition, the TPG heat dissipation improves the current density uniformity to almost the same as that of oil cooling with the TPG giving a lower temperature difference of less than 5 K. The parasitic power with the TPG heat dissipation is 9.5 % less and the stack volume and weight are 14.2 % and 2 % less than with oil heat dissipation with a temperature difference of 10 K in the MEA. [ABSTRACT FROM AUTHOR]

The synergistic effect between metal and acid sites has been considered to be of great importance to n-alkane hydroisomerization catalyzed by bifunctional catalysts. Herein, we report a facile mercaptosilane-assisted in situ synthesis approach to achieve stable and highly dispersed small Pt nanoparticles supported on HL zeolite catalysts (Pt/HL-SH) for n-hexane hydroisomerization. In comparison with the catalysts (Pt/HL-C) synthesized by a traditional ion-exchange method, the Pt/HL-SH catalysts show both high activity and excellent catalytic stability and also no obvious sintering of Pt nanoparticles is observed during the reaction due to the fact that the Pt/HL-SH catalysts possess both higher dispersion of Pt particles within the HL nanocrystals and more mesopores produced by mercaptosilane. Moreover, the regeneration stability of n-hexane hydroisomerization over Pt/HL-SH catalysts was also examined by five continuous cycles, demonstrating excellent regeneration properties. Thus, the mercaptosilane-assisted in situ synthesis approach is a promising way to prepare bifunctional catalysts for enhancing their catalytic performance in n-alkane hydroisomerization. [ABSTRACT FROM AUTHOR]

Incorporating mesopores into ZSM-5 zeolite to form a hierarchical structure has been regarded as an important approach to enhance the diffusivity and catalyst lifetime for light alkane aromatization. Herein, hierarchical ZSM-5 nano-aggregated microspheres were simply and directly synthesized and characterized using TPAOH as a single template without any mesoporous templates or zeolite seeds. The size of the ZSM-5 microspheres and the distribution of mesopores could be regulated by controlling the alkalinity of the synthesis gel. A possible self-assembly mechanism was proposed based on tracing the formation process of ZSM-5 microspheres with crystallization time. The ZSM-5 microspheres modified with Zn were applied in n-hexane aromatization and exhibited better catalytic stability than conventional mono-dispensed microporous ZSM-5 due to the existence of accessible mesopores. [ABSTRACT FROM AUTHOR]

Large-scale complex surfaces are the core components of large aircraft, ships, and wind turbine generators. High-accuracy manufacturing of the components is very crucial for its performance. Automated and high-accuracy large-scale 3-D measurement is an effective means for the manufacturing accuracy control of these components. This article proposes an automated mobile robotic profile measurement method for large-scale complex surfaces, and it also proposes a high-accuracy point clouds alignment algorithm to improve the measurement accuracy. A fringe projection scanner, integrated on the end of a mobile robot, is utilized to scan the surface and obtain the local scanning point clouds. The local scanning point clouds’ coarse alignment is implemented using the robot’s joint data and the laser sensor’s positioning data. After that, a fine alignment algorithm combining the fruit fly optimization algorithm (FOA) with the improved iterative closest point (IICP) algorithm is proposed for point clouds’ fine alignment. Practical measurement was performed on a sectional wind turbine blade, and a broad region of $4.6 \text { m} \times 2.6$ m was measured. An accuracy evaluation method based on point-to-plane distance was adopted to evaluate the measurement error. The result that the mean distance error is less than 0.4 mm shows the proposed mobile robotic measurement system and the aligning method are of high accuracy. [ABSTRACT FROM AUTHOR]

3D scaffolds and heterogeneous seeds are two effective ways to guide Li deposition and suppress Li dendrite growth. Herein, 3D TiO2 nanotube (TNT) arrays decorated using ultrafine silver nanocrystals (7–10 nm) through cathodic reduction deposition are first demonstrated as a confined space host for lithium metal deposition. First, TiO2 possesses intrinsic lithium affinity with large Li absorption energy, which facilitates Li capture. Then, ultrafine silver nanocrystals decoration allows the uniform and selective nucleation in nanoscale without a nucleation barrier, leading to the extraordinary formation of lithium metal importing into 3D nanotube arrays. As a result, Li metal anode deposited on such a binary architecture (TNT‐Ag‐Li) delivers a high Coulomb efficiency at around 99.4% even after 300 cycles with a capacity of 2 mA h cm−2. Remarkably, TNT‐Ag‐Li exhibits ultralow overpotential of 4 mV and long‐term cycling life over 2500 h with a capacity of 2 mAh cm–2 in Li symmetric cells. Moreover, the full battery with 3D spaced Li nanotubes anode and LiFeO4 cathode exhibits a stable and high capacity of 115 mA h g–1 at 5 C and an excellent Coulombic efficiency of ≈100% over 500 cycles. [ABSTRACT FROM AUTHOR]

Due to stricter regulations, large biomass/waste incineration power plants are expected to reduce (i) pollutant emissions through water (such as organic compounds dissolved in the discharge water), (ii) the withdrawal of external freshwater, and (iii) the disturbance to the natural water by increasing the water recycle and internal reuse. To address such challenges, flue gas quench (FGQ) is playing a vital role that links flue gas (FG) cleaning and wastewater treatment. In this study, a detailed analysis based on the material and energy balance is performed regarding the pollutant distribution in the flue gas and the wastewater within a combined heat and power (CHP) plant. The real data from the reference CHP plant were used; and results show that the utilization of FGQ can result in less wastewater discharge (about 73 tonnes/d) together with less pollutant concentration to the municipal wastewater treatment plant, as compared to the system with only flue gas condenser but without FGQ. The integration of FGQ also results in less burden on the external freshwater use by increasing the amount of clean water for internal use (about 57 tonnes per day). In addition, the integration of FGQ can offer a potential annual energy saving of about 13.1 MWh in the municipal wastewater treatment plant due to the less wastewater coming from the CHP plant. [ABSTRACT FROM AUTHOR]

Narrowband emitters possess great potential in organic light emitting diodes (OLEDs) to achieve high color purity. However, developing highly efficient pure blue emitters with a simultaneously narrow full width at half-maximum (FWHM) value is a major challenge due to the energy-gap law and molecular stacking effect. Few efforts have focused on this challenging pursuit. Herein, an ingenious synthetic method was devised to achieve pure blue emitters incorporating bulky rigid planes as donors and highly twisted steric units as acceptors. Four emitters with aggregation-induced emission (AIE) characteristics, namely BCzPPM, BC-zPSP, IDCz-DBPM, and IDCz-BPSP, have been developed and used to fabricate non-doped devices. IDCz-BPSP achieves narrowed photoluminescence (PL) and electroluminescence (EL) with the benefit of suppressing vibronic coupling. Non-doped OLEDs based on IDCz-BPSP have achieved maximum external quantum efficiency (EQE max) of 4.61% with a FWHM of 25 nm/0.20 eV. The Commission Internationale de L'Eclairage (CIE) coordinates was (0.154, 0.059), with CIE y being superior to the standard of European Broadcasting Union (EBU) 0.06. The hybridized local and charge-transfer (HLCT) states of IDCz-BPSP have simultaneously boosted the PL efficiency and exciton utilization. The EL process has even achieved exciton utilization at exceeding the theoretical limit of 25%. These results indicate that the strategy of combining bulky rigid plane donor units and steric hindrance effect is a favorable strategy for constructing emitters with narrow FWHM. [Display omitted] • A "single bond-linked" strategy for deep blue AIE emitters was proposed. • The HLCT states of IDCz-BPSP have simultaneously boosted the PL efficiency and exciton utilization. • IDCz-BPSP exhibits a narrow PL and EL FWHM of 24 nm (0.19 eV) and 25 nm (0.20 eV), respectively. • Non-doped OLEDs based on IDCz-BPSP provided ultrapure deep blue emission with CIE y ＜0.06. [ABSTRACT FROM AUTHOR]

Three aggregation-induced emission (AIE) and thermally activated delayed fluorescence (TADF) blue light-emitting materials were successfully synthesized using bicarbazole and phenylsulfonyl/benzophenone moieties as electron donors and acceptors, respectively, via Buchwald-Hartwig reaction. Density functional theory calculations showed that the three emitters have a moderate dihedral angle between the two carbazole planes and between the donor and acceptor, resulting in a good conjugated structure and a trade-off between the small Δ E ST and high photoluminescence quantum yield of the BCzDPM molecule. The cyclic voltammetry, thermogravimetric analysis and differential scanning calorimetry tests demonstrated that the three materials had high electrochemical and thermal stability. The three emitters exhibited obvious intramolecular charge transfer characteristics in solution and film. According to the fluorescence and low-temperature phosphorescence spectra, the lowest singlet and triplet excited state energy levels of BCzDPM were 2.96 eV and 2.78 eV, respectively, with a Δ E ST of 0.18 eV. Using these emitters as non-doped emissive layers, efficient blue electroluminescent devices were fabricated. The maximum current efficiency and external quantum efficiency reached 15.4 cd/A and 7.05% for the BCzDPM device, respectively, and the efficiency roll-off of BCzDPM was smaller than that of PSOBCz and PBCzPM, under high current density. [Display omitted] • The twisted molecule has a moderate dihedral angle, resulting in a trade-off between small Δ E ST and high Φ PL. • BCzDPM simultaneous combination of AIE and TADF properties. • BCzDPM exhibit small Δ E ST of 0.18 eV and high Φ PL of 67%. • BCzDPM film has high k ISC , k RISC , and k F values implying rapid decay of T 1.→S 1 and S 1 →S 0 for emission. [ABSTRACT FROM AUTHOR]

Abstract Currently, aggregation-induced delayed fluorescence (AIDF) is the most potential method that overcomes the limitations of thermally activated delayed fluorescence (TADF) emitters. Herein, to develop high efficient AIDF emitters, a novel strategy of introducing carbazole dendrites to a strengthen electron acceptor to construct D−π−A structure has been presented. Two emitters, namely diphenyl(4-(4-phenyl-6-(4-(3,3″,6,6″-tetra- tert -butyl-9′H-[9,3':6′,9″-tercarbazol]-9′-yl)phen yl)-1,3,5-triazin-2-yl)phenyl) phosphine oxide (CzTAZPO) and diphenyl(4-(4-phenyl-6-(4-(3,3″,6,6″-tetra- tert -butyl-9′H-[9,3':6′,9″-tercarbazol]-9′-yl)phenyl)-1,3,5-triazin-2-yl)phenyl)phosphine oxide (sCzTAZPO) with a twisted carbazole dendrites structure are synthesized and investigated theoretically and experimentally. Both compounds show aggregation-induced emission, a prominent TADF and bipolar properties. The reasonable molecular design strategy allows CzTAZPO to exhibit high oscillator strengths (f) and small singlet–triplet energy gap (Δ E ST) at the same time, which signifcantly increase the rate of reverse intersystem crossing process and fluorescence quantum efficiency. High-performance nondoped OLEDs are fabricated with CzTAZPO neat films as the emission layers, providing excellent maximum current efficiency (CE max) and maximum external quantum efficiency (EQE max) of 29.1 cd A−1 and 12.8%, respectively. More importantly, nondoped OLEDs provided negligible EQE roll-off of 1.6% from the maximum values to those at 1000 cd m−2. The AIDF emitters with small Δ E ST , high photoluminescence quantum yields (Φ PL), bipolar charge transport and high rate constant of reverse intersystem crossing process are promising candidates for OLEDs that are roll-off-free and possess high efficiency. Graphical abstract Image 1 Highlights • A strategy to construct solution-processed AIDF was proposed. • Two solution-processed AIDF emitters were designed and synthesized. • CzTAZPO exhibit high oscillator strengths and small singlet–triplet energy gap. • CzTAZPO based nondoped OLED shown high efficiencies (EQE>12%) and low roll-off (<1.6%). • This strategy would be a promising method for efficient and stable OLEDs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • TPPOCz with behavior was employed as the host to fabricate PhOLEDs. • TADF host can enhance device performance and reduce efficiency roll-off. • High efficiencies of 43.6 cd A−1 and 20.4% were achieved for blue PhOLEDs. • All PhOLEDs exhibit small efficiency roll-off. Abstract Numerous efforts have been devoted to improve the device efficiency of phosphorescent organic light-emitting diodes (PhOLEDs), however, strategies to suppress the device efficiency roll-off are still in urgent need. Here, a general and effective approach to boost the efficiency and suppress the efficiency roll-off of PhOLEDs is proposed, that is, utilizing TADF material with high triplet energy (E T) as the host for blue, orange and red phosphorescent dopants is proposed. In this work, we investigate the performance of these PhOLEDs based a new TADF host phenylbis(4-(3,3″,6,6″-tetra- tert -butyl-9′H-[9,3′:6′,9″-tercarbazol]-9′-yl)phenyl)phosphineoxide (TPPOCz). The blue device based on the TPPOCz host exhibit efficiencies of 43.6 cd A−1 and 20.4%, and small efficiency roll-off of 2.1% and 2.9% for CE and EQE from the peak efficiencies to these at 1000 cd m−2. We compared the performances with that reported in literature, and confirmed these devices in this work are among the best of PhOLEDs. These results can be ascribed to the rapid reverse intersystem crossing (RISC) process and high triplet energy (E T). These excellent performances indicating the potential of TADF host for the realization of highly efficient and stable devices in future. [ABSTRACT FROM AUTHOR]

Due to the limited molecular design strategy, the development of ultrahigh color purity deep blue aggregation-induced emission (AIE) emitters with excellent photophysical and electroluminescence performances is still facing challenges at present. In this study, an effective design strategy for deep blue emitters is proposed, which can improve the performances of non-doped organic light-emitting diodes (OLEDs) by adjusting the link mode of the phenyl bridge and utilizing the steric hindrance effect of the rigid plane. Two new emitters, 3BCzPT and 4BCzPT, were obtained with phenanthroline acceptor and carbazole donor for deep blue emitting OLEDs. Particularly, 3BCzPT has been proven to have AIE characteristics through photophysical properties. Non-doped OLEDs with 3BCzPT demonstrate prominent electroluminescence (EL) performances reaching a maximum current efficiency (CEmax) of 6.3 cd A−1 and maximum external quantum efficiency (EQEmax) of 3.81%, well as ultrahigh color purity with Commission Internationale de L'Eclairage (CIE) coordinates of (0.151, 0.053). While the parameters of non-doped OLED based 4BCzPT are 4.2 cd A−1, 1.96% and (0.147, 0.082). Both emitters exhibit narrow EL spectra with the full-width at half maximum (FWHM) of 56 and 52 nm. • A strategy to construct deep blue AIE emitters with D-π-A-π-D configuration was proposed. • Highly twisted configurations are beneficial to the formation of weak intra/intermolecular interaction. • Non-doped OLEDs provided ultrapure deep blue emission with CIE x ≤0.15 and CIE y ≤0.08. • This feasible strategy can enrich the design strategy of deep blue emitters and further extend their application in OLEDs. [ABSTRACT FROM AUTHOR]

Two fluorescent emitters, namely, phenylbis(4-(3,3″,6,6″-tetra- tert -butyl-9′H-[9,3′:6′,9″-tercarbazol]-9′-yl)phenyl)phosphineoxide (TPPOCz) and 9′,9‴′-(sulfonylbis(4,1-phenylene))bis(3,3″,6,6″-tetra- tert -butyl-9′H-9,3′:6′,9″- tercarbazole) (DBSOCz) are constructed. These compounds emit deep-blue and bluish-green signals and feature triphenylphosphine oxide/sulfonyldibenzene as electron acceptor core and carbazole dendrite as electron donor encapsulation groups. A simple construction strategy functionalizes these emitters to exhibit high thermal stability, suitable highest occupied molecular orbital/lowest unoccupied molecular orbital levels, relatively high photoluminescent quantum yields, and good film-forming capability. Emission spectrum and quantum computation were used to confirm that TPPOCz and DBSOCz possess small singlet–triplet energy splitting (0.22 and 0.10 eV). As a result, these fluorescent emitters exhibit significant thermally activated delayed fluorescence features with a short delayed fluorescence lifetime. Consequently, solution-processed OLEDs featuring DBSOCz as the non-doped emitter achieved a maximum current efficiency of 15.5 cd/A and external quantum efficiency of 7.65%. Surprisingly, the DBSOCz-based device exhibits an ultraslow current efficiency roll-off of 4.5% at a high luminance of 3000 cd/m 2 . The value represents almost the lowest attenuation of current efficiency in thermally activated delayed fluorescence-based OLEDs. [ABSTRACT FROM AUTHOR]

A new blue-emitting dendrimer DCzFIrpic, has been successfully designed and synthesized with an iridium-cored as triplet emitter, which is covalently attached to a carbazole dendron through a non-conjugated linkage to form a self-host system. This phosphor possesses high thermal stability ( T g = 197 °C), suitable HOMO/LUMO levels (−5.42 eV/−2.53 eV), relatively high PLQY (79%) in neat films. As a result, this dendrimer was used to form a self-host system for solution-processed non-doped PhOLEDs. The blue-emitting devices achieved a superior CE max of 15.6 cd/A and an EQE max of 6.4%. Moreover, it is worth noting that there is a relatively flat efficiency roll-off from the peak efficiencies to the efficiencies at the brightness of 1000 cd/m 2 (decreased 1.2% and 3.0%, respectively). This is mainly caused by the less phase segregation in such self-host system, and the molecular dynamics simulations have demonstrated it. At the same time, we noticed that the CE of this non-doped device is 1.6–2.7 fold than that of doped devices at the brightness of 1000 cd/m 2 , which indicated that this non-doped device is much more suitable for display. [ABSTRACT FROM AUTHOR]

Two polymeric hosts PCzTPP and PCzTPPO with twisted geometrical configurations for blue phosphorescent polymer light-emitting diodes (PhPLEDs) were designed and synthesized by incorporating electron-accepting carbazole units with electron-donating TPP/TPPO groups. This molecular design endows PCzTPP and PCzTPPO with high glass transition temperatures of 204 °C and 215 °C, high triplet energies of 2.72 eV and bipolar features. In addition, the HOMO and LUMO of these polymers matched well with the HOMO of the hole-transport layer and the Fermi level of cathode compared with PVK, which facilitated the injection of holes and electrons. PCzTPP- and PCzTPPO-based single-emissive-layer blue PhPLEDs were fabricated with simplified device configuration by solution process using FIrpic as a dopant. These devices exhibited lower turn on voltages (<8 V) than PVK-based devices (12 V). The maximum luminances of PCzTPP- and PCzTPPO-based devices were twofold and threefold that of PVK-based devices, and the maximum current efficiencies were nearly threefold and ninefold, respectively. Moreover, PCzTPPO-based solution processed blue PhPLEDs with improved configuration showed maximum current efficiency and external quantum efficiency of 14.5 cd/A and 6.6%, respectively. [ABSTRACT FROM AUTHOR]

We report an ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) method to quantify all- trans -retinal in biological samples of limited size (15–35 mg), which is especially advantageous for use with adipose. To facilitate recovery, retinal and the internal standard 3,4-didehydroretinal were derivatized in situ into their O -ethyloximes. UHPLC resolution combined with high sensitivity and specificity of MS/MS allowed quantification of retinal- O -ethyloximes with a 5-fmol lower limit of detection and a linear range from 5 fmol to 1 pmol. This assay revealed that extraocular concentrations of retinal range from approximately 2 to 40 pmol/g in multiple tissues—the same range as all- trans -retinoic acid. All- trans -retinoic acid has high affinity ( k d ⩽ 0.4 nM) for its nuclear receptors (RARα, -β, and -γ), whereas retinal has low (if any) affinity for these receptors, making it unlikely that these retinal concentrations would activate RAR. We also show that the copious amount of vitamin A used in chow diets increases retinal in adipose depots 2- to 5-fold relative to levels in adipose of mice fed a vitamin A-sufficient diet, as recommended for laboratory rodents. This assay also is proficient for quantifying conversion of retinol into retinal in vitro and, therefore, provides an efficient method to study metabolism of retinol in vivo and in vitro. [ABSTRACT FROM AUTHOR]

Feline infectious peritonitis virus (FIPV) causes a lethal systemic granulomatous disease in wild and domestic cats around the world. Currently, no effective vaccines or drugs have been developed against it. As a member of the genus Alphacoronavirus, FIPV encodes two polyprotein precursors required for genome replication and transcription. Each polyprotein undergoes extensive proteolytic processing, resulting in functional subunits. This process is mainly mediated by its genome-encoded main protease, which is an attractive target for antiviral drug design. In this study, the main protease of FIPV in complex with a Michael acceptor-type inhibitor was crystallized. The complex crystals diffracted to 2.5 Å resolution and belonged to space group I422, with unit-cell parameters a = 112.3, b = 112.3, c = 102.1 Å. There is one molecule per asymmetric unit. [ABSTRACT FROM AUTHOR]

A novel iridium(III) complex bis(2-(naphthalen-1-yl)-6-(trifluoromethyl)benzothiazole)iridium(acetylacetonate) (CF 3 BT-N) 2 Ir(acac) with an orange–red emission was synthesized. The incorporation of CF 3 and naphthalene groups into benzimidazole to act as a new ligand causes a significant change of both HOMO and LUMO energy levels of the iridium complex compared with the yellow emissive parent compound comprising the 2-phenylbenzimidazole ligand. As a result, a bathochromic shift by as much as 50 nm of the phosphorescence emission peak can be achieved. Electronic properties of (CF 3 BT-N) 2 Ir(acac) were examined by time-dependent density functional theory (TD-DFT) calculations. The influence of such substituent groups on the photophysical, electrochemical and electroluminescent properties of iridium complex was studied. Furthermore, two- and three-element solution-processed white organic light-emitting diodes (WOLEDs) with high performance can be realized by using this kind of orange–red phosphorescent emitter in conjunction with other phosphors in a single emissive layer. A maximum luminous efficiency of 10.9 cd A −1 with CIE coordinates of (0.27, 0.37) was obtained for the two-element WOLEDs. For the three-element WOLED, a maximum luminance of 22716 cd m −1 and a maximum luminous efficiency of 14.6 cd A −1 with CIE coordinates of (0.33, 0.42) can be achieved. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D spaced TiO 2 nanotube arrays (STNTs) were coated with ultra-fine metal nanocrystals. • We propose an absorption-diffusion regulation strategy to regulate Na deposition. • AIMD simulations demonstrate a mixed Na-Ag layer at the interface. • STNTs-Ag||Na displays a high Coulombic efficiency ∼99.5% even after 500 cycles. • STNTs-Ag-Na exhibits an ultralow overpotential of 4 mV and long cycling life over 1400 h. Sodium metal is considered as an excellent anode material for sodium-based energy storage devices with both high energy density and low cost, but the uncontrollable growth of sodium metal seriously limits its application. Herein, we firstly propose 3D spaced TiO 2 nanotube arrays (STNTs) uniformly coated with ultra-fine metal (Ag, Cu) nanocrystals as a substrate with absorption-diffusion regulation strategy to control the sodium metal deposition behavior. TiO 2 has a higher sodiophilic activity with larger Na absorption energy than the traditional copper substrate. Moreover, it is found by ab initio molecular dynamics (AIMD) simulations that it is much easier for Na to spread upon the surface of silver compared to copper, and thus forming a mixed Na-Ag layer at the interface. As a result, sodium metal is inclined to deposit inside or along the nanotube in STNTs-Ag in nanoscale. Finally, STNTs-Ag||Na half-cell displays a high Coulombic efficiency ∼99.5% even after 500 cycles with 1 mAh cm−2. Symmetric cell of STNTs-Ag-Na exhibits an ultralow overpotential of 4 mV and a long-term cycling life over 1400 h. Moreover, STNTs-Ag-Na anode coupling with Na 3 V 2 (PO 4) 3 cathode exhibits a significantly reduced polarization voltage with 22 mV and improved rate performance with 110 mAhg−1 at 10 C. [ABSTRACT FROM AUTHOR]

[Display omitted] • LTL-zeolite was used as a novel support for selective phenol hydrogenation. • LTL has one-dimensional large-pore diffusion system and adjustable base-acid sites. • Palladium nanoparticles were in-situ encapsulated within LTL-zeolite. • High Pd dispersions were obtained after encapsulation. • Switching chemical microenvironments around Pd sites changed the kinetic profiles. Cyclohexanone, as a significant raw material in the production of nylon 6 and nylon 66, is preferentially synthesized via selective phenol hydrogenation while the key point is to modulate the acidic/basic properties and metal dispersion of the catalytic system. Here, we report the fabrication of Pd@L core–shell catalysts via the in-situ encapsulation of Pd nanoparticles within the L zeolite with a one-dimensional large-pore diffusion system for the selective hydrogenation of phenol to cyclohexanone. The different Pd amounts and acidic/basic properties of the L zeolite catalyst were modulated to study the effects of the microenvironment around the Pd centers in the Pd@L on the catalytic performances of selective phenol hydrogenation. The results show that the basicity of L zeolite greatly favors high selectivity to cyclohexanone. In contrast, modulating the microenvironment to weak or strong acid states can result in the dehydration product forming on the acid sites or even the suppression of phenol hydrogenation. The conversion of phenol increases from 14.0% to 99.9% and meanwhile the selectivity of cyclohexanone ranges from 67.5% to 93.8%. In the optimum condition, the obtained Pd@KL catalyst can demonstrate excellent catalytic performance with the phenol conversion of 99.9% and the cyclohexanone selectivity of around 93.8%. Our work presents a promising tactic to effectively control the target reaction pathway by means of maneuvering the microenvironment in the proximity of metal nanoparticles. [ABSTRACT FROM AUTHOR]

In the production of cyclohexene by benzene hydrogenation, the by-product cyclohexane forms an azeotrope with cyclohexene. For the extraction and distillation of the binary azeotrope (cyclohexene + cyclohexane), the selectivity and relative volatility of 24 different entrainers were compared and the intermolecular interaction forces and interaction energies were analyzed by the DMol3 module of Materials Studio (MS). N, N-dimethylformamide (DMF) was identified as the entrainer, and vapour–liquid equilibrium (VLE) data were measured at atmospheric pressure for the binary system {cyclohexane + cyclohexene} with a temperature range of 354 K to 356 K, the binary system {cyclohexane + DMF} with a temperature range of 354 K to 390 K, and the binary system {cyclohexene + DMF} with a temperature range of 357 K to 421 K. In addition, the thermodynamic consistency of the experimental data was checked using the Wisniak and Van Ness method. The Wilson, NRTL, and UNIQUAC models were used to regress and fit the experimental data to optimize the binary interaction parameters, and the root mean square (RMSD) and average absolute deviation (AAD) values of all models were below 0.01%, indicating that the experimental data provide a basis for the simulation and optimization of the extractive distillation process. [ABSTRACT FROM AUTHOR]

Immunogenic cell death (ICD) is a newly discovered form of cellular demise that triggers adaptive immune responses mediated by T cells. However, the immunogenic cell death-related lncRNAs (ICDRLs) involved in bladder cancer (BC) development and progression remain to be further elucidated. Molecular profiling data and clinicopathological information for BC patients were obtained from TCGA, and the ICDRGs list was obtained from published literature. For the identification of ICDRLs, Pearson co-expression analysis was performed, and a prognostic signature based on 13 ICDRLs was constructed by univariate assays and LASSO assays. Herein, an ICDRLSig consisting of 13 ICDRLs was constructed. KM curves and ROC curves demonstrated that the constructed signature in the TCGA training, testing, entire and external sets have good predictive performance. Multivariate assays illuminated that the signature is an independent predictor for BC patients' OS, exhibiting greater predictive power for the survival than traditional clinicopathological features. Additionally, patients in the high-ICDRLSig risk subgroup had more abundant immune infiltration, higher immune checkpoint gene expression, lower TMB and poorer response to immunotherapy. We have developed a novel ICDRLSig that can be exploited for survival prediction and provide a reference for further individualized treatment. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the value of ultrasound-guided percutaneous nephrostomy and nephrostomy tube replacement for treating a solitary kidney with hydronephrosis due to renal tuberculosis. Methods: Clinical data of patients with a solitary kidney with hydronephrosis caused by renal tuberculosis who underwent ultrasound-guided percutaneous nephrostomy in our hospital from January 2011 to December 2022 were retrospectively analyzed. The associated success rate and complications were statistically analyzed, pre- and post-catheterization changes in serum creatinine and blood urea nitrogen levels were compared, success rate and complications of nephrostomy tube replacement in patients with long-term catheterization were statistically analyzed, and the impact of long-term catheterization on patient life was investigated. Results: Overall, 32 patients aged 17–75 years (average age: 44.1 ± 16.9 years) underwent ultrasound-guided percutaneous nephrostomy. Sixty-three punctures were performed; the puncture success rate was 100%. The levels of serum creatinine and blood urea nitrogen of patients decreased after catheterization, and the differences between the pre-catheterization and post-catheterization were significant (P < 0.05). There were 1, 3, and 12 cases of serious, minor, and fistula-related complications, respectively. The mean duration of the indwelling catheter was 56.7 ± 36.2 (range, 13–120) months. The number of nephrostomy tube replacements was 344 times, and the success rate was 100%. All patients could take care of the puncture point by themselves. Conclusion: Ultrasound-guided percutaneous nephrostomy and nephrostomy tube replacement have a high success rate and few complications, which can improve the renal function of patients. It is of great value for treating a solitary kidney with hydronephrosis caused by renal tuberculosis. [ABSTRACT FROM AUTHOR]

Local heat can accelerate the blood circulation and induce the vasodilatation. Investigators reported that local heat causes an increase in skin blood flow consisting of two phases. The first is solely sensory neural, and the second is nitric oxide mediated. However, the mechanism underlying the skin blood flow response to local heating are complex and poorly understood. The mechanisms behind these two phases are deduced to be linked by flow-mediated dilation. In this study, the variation of the blood flow and the blood vessel diameter are monitored during local heating. According to the dynamic blood flow, the theoretical model of flow mediated dilation involving the key agents production and transportation was first used to study vasodilatation process during heating, and the variations of blood vessel was obtained. Finally, accurate distributions of the nitric oxide, calcium and myosin concentrations in the arterial wall were found during autoregulation. We evaluated the time course of the blood vessel changing and verified the fact that the second increase in blood flow is the result of flow dilation mediation. The effects of dilation of blood vessel were also analyzed. • Flow-mediated dilatation response of the blood vessel was predicted during hyperthermia. • The related agents production and diffusion during autoregulation process was obtained and demonstrated. • A direct link between the mechanisms of the neural- and NO-mediated increases in flow was established. [ABSTRACT FROM AUTHOR]

Objective MicroRNAs (miRNAs) are a class of small noncoding RNAs that play important roles in tumor development and progression. miR-20a acts as an oncogene in many cancers; however, the underlying role of miR-20a in human glioma remains unknown. Methods Glioma tissue samples were obtained from 32 patients with primary glioma who had undergone surgery at the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China). Twenty-two normal brain tissue samples used as controls were obtained by internal decompression in patients who had undergone surgery for cerebral injury and cerebral hemorrhage at the same hospital. Results Quantitative reverse transcription polymerase chain reaction showed upregulation of miR-20a in glioma tissues and cell lines compared with normal brain tissue and normal human astrocytes. Functional assays showed that miR-20a promotes proliferation and invasion and inhibits apoptosis in glioma cells. The bioinformatic analysis showed that CELF2 (CUGBP Elav-like family member 2) is a direct target gene of miR-20a, which was confirmed using a luciferase reporter assay. Downregulation of CELF2 reversed the effects of inhibiting miR-20a expression. Conclusions Collectively, these results suggest a critical role for miR-20a in glioma cell apoptosis, proliferation, and invasion via the direct targeting of CELF2 and indicate its potential application in cancer therapy. Highlights • miR-20a is upregulated in glioma tissues and cell lines. • miR-20a promotes proliferation and invasion and inhibits apoptosis in glioma cells. • miR-20a affected glioma cell growth by targeting CELF2. • Downregulation of CELF2 reversed the effects of inhibiting miR-20a expression. • miR-20a has potential application in glioma therapy. [ABSTRACT FROM AUTHOR]

In order to reduce the environmental pollution caused by plastic packaging, the development of biodegradable high-performance packaging materials has become a research hotspot. Cellulose is a promising food packaging material, but it usually lacks sufficient ultraviolet (UV) shielding property and mechanical strength. In this work, rectorite microplates were incorporated into the cellulose matrix by a facile blending method to fabricate the composite films. The structure and properties of the composite films were characterized by FT-IR, X-ray diffraction, scanning electron microscopy, UV–vis and mechanical properties test etc. The results indicated that rectorite microplates were uniformly distributed in the cellulose matrix. The blocking percentages for UVA and UVB for the cellulose/rectorite composite film with 14 wt% rectorite content (RCRF-14) could reach as high as 97.8 % and 96.0 %, respectively, showing a good UV shielding property. Meanwhile, the addition of rectorite obviously improved the mechanical properties and decreased the water vapor and oxygen permeabilities of the cellulose film, showing a potential application as a sustainable food packaging material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogenation of conjugated C = O is thermodynamically unfavored. • Highly dispersed Pt nanoparticles are well-embedded within S-1 microchannel. • Confinement effect of S-1 is employed to improve unsaturated alcohol selectivity. • C = O group is preferentially adsorbed on Pt@S-1 via on-top η 1 mode. • The on-top η 1 adsorption mode is more favored to C = O hydrogenation than d i -σ CO η 2. The issue for thermodynamically favored C = C hydrogenation needs to be overcome in the hydrogenation of ɑ, β-unsaturated aldehydes to unsaturated alcohols. Herein, we employ confinement effect in the catalyst-designing engineering to orient the C = O adsorption by the zeolitic microchannel, where highly dispersed Pt nanoparticles are homogeneously well-embedded within the silicalite-1 framework (Pt@S-1). Comprehensive characterizations, such as HAADF-STEM, H 2 -TPR, FT-IR of CO adsorption and XPS are carried out to demonstrate the geometric, confinement and electronic properties of metal species. In the hydrogenation of ɑ, β-unsaturated aldehydes with suitable molecular size, Pt@S-1 displays preferential C = O hydrogenation. For example, Pt@S-1 gives conversion of 99.8% and meanwhile the aiming cinnamal alcohol selectivity of 98.7% in the hydrogenation of cinnamaldehyde, outperforming larger Pt nanoparticles ill-suitedly embedded within silicalite-1 (Pt@S-1- is) and highly dispersed Pt nanoparticles supported on the silicalite-1 surface (Pt/S-1). For the hydrogenation of smaller 3-methyl-2-butenal, though the confinement effect boosts the C = O hydrogenation to some extent, the synergetic electronic effect via introducing Fe species effectively increases the unsaturated alcohol selectivity. Investigations on the adsorption configuration by in-situ FT-IR spectroscopy clearly indicate that the unsaturated aldehyde with suitable molecular size is preferentially adsorbed on Pt sites of Pt@S-1 via the oxygen atom of C = O with on-top η 1 mode, thus favoring high unsaturated alcohol selectivities, while the d i -σ CO η 2 and η 4 adsorption modes on Pt@S-1- is and Pt/S-1 are relatively adverse for prioritized C = O hydrogenation. [ABSTRACT FROM AUTHOR]

We report a simple strategy to prepare organic–inorganic hybrid nanoparticles with enhanced fluorescence. A significant fluorescence enhancement was realized by designing a fluorescent small molecule of 9,9′-(6,6′-(2-(4-(1,2,2-triphenylvinyl)phenyl)-9 H -fluorene-9,9-diyl)bis(hexane-6,1-diyl))bis(9 H -purin-6-amine) (TPEFA) possessing an aggregation-induced emission enhancement effect. Nanoparticles of TPEFA can be formed through molecular self-aggregation by gradually changing the water fraction in the TPEFA mixed solution of tetrahydrofuran (THF) and water, and fluorescence enhancement of about 445-fold was observed after nanoparticle formation. By coating the formed TPEFA nanoparticles with a silica (SiO 2 ) shell, the dispersibility of these fluorescent nanoparticles was greatly improved, becoming easily separated and concentrated after possessing the inorganic silica layer coating. This method solves the difficulty, common among organic nanoparticles, of problematic separation because of the low nanoparticle weight. Cyanic fluorescence from TPEFA@SiO 2 nanoparticles can be clearly observed from confocal laser scanning microscope images, and the cyanic spots are bright and well dispersed, which proved the good dispersibility of the prepared fluorescent nanoparticles. Finally, a cellular internalization assay and a cell viability assay demonstrate that the TPEFA@SiO 2 nanoparticles can be applied in cellular imaging. [ABSTRACT FROM AUTHOR]

• The LLE data of water + epichlorohydrin + solvents (1-hexanol/1-heptanol/2-octanol/1-nonanol) were measured. • The measured LLE data were correlated by UNIQUAC and NRTL models. • The interaction between component molecules was explored through σ-Profiles. • The reliability of LLE data and binary interaction parameters were verified by the GUI-MATLAB. In order to remove epichlorohydrin from wastewater, liquid–liquid equilibrium behaviors in the systems {water + epichlorohydrin + solvents (1-hexanol/1-heptanol/2-octanol/1-nonanol)} were determined at 303.2 K under101.3 kPa. The partition coefficients and separation factors in each system were used to compare and discuss the effects of extraction. The σ-profiles were used to discuss the interactions of substances in this work. The experimental data were correlated with the NRTL and UNIQUAC models, to obtain the binary interaction parameters required for each system. The GMcal_TieLinesLL GUI tools were applied to verify the consistency of the binary interaction parameters. [ABSTRACT FROM AUTHOR]

Consider the heterogeneity (e.g., heterogeneous social behaviour, heterogeneity due to different geography, contrasting contact patterns and different numbers of sexual partners etc.) of host population, in this paper, the authors propose an infection age multi-group SEIR epidemic model. The model system also incorporates the feedback variables, where the infectivity of infected individuals may depend on the infection age. In the direction of mathematical analysis of model, the basic reproduction number R0 has been computed. The global stability of disease-free equilibrium and endemic equilibrium have been established in the term of R0. More precisely, for R0 ≤ 1, the disease-free equilibrium is globally asymptotically stable and for R0 > 1, they establish global stability of endemic equilibrium using some graph theoretic techniques to Lyapunov function method. By considering a numerical example, they investigate the effects of infection age and feedback on the prevalence of the disease. Their result shows that feedback parameters have different and even opposite effects on different groups. However, by choosing an appropriate value of feedback parameters, the disease could be eradicated or maintained at endemic level. Besides, the infection age of infected individuals may also change the behaviour of the disease, global stable to damped oscillations or damped oscillations to global stable. [ABSTRACT FROM AUTHOR]

Hollow zeolites have been considered as promising materials due to their unique porosity. Although some progress has been made in the synthesis of hollow zeolites, there are still few reports on the one-step synthesis of high-quality hollow ZSM-5 zeolites. In this work, we used a simple one-step strategy to synthesize high-quality bowl-like hollow ZSM-5 zeolites without additional templates. The strategy involves two key factors including the hydrolysis temperature of TEOS (tetraethoxysilane) and the amount of NaOH. During the preparation of the synthesis gel, the hydrolysis temperature of TEOS was carefully controlled to tune the spatial distribution of Al and Si throughout the micelle/nucleus, creating Al-zoning and a Si-rich core for the formation of intracrystalline macropores. The amount of Na+ was adjusted to change the competitive electrostatic interactions with TPA+ for negatively charged groups on the surface of crystals, producing bowl-like macropores on the shell of crystals. Various characterizations were made and the formation mechanism of bowl-like hollow ZSM-5 zeolites was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] In this paper, the experimental results indicated that the hydrostatic pressure descent (HPD) curves of cement slurry include a stabilization stage, slow descent stage, and rapid descent stage. In the stabilization stage, the gravity of the solid particles dispersed in pore water was effectively transferred by the pore water. In the slow descent stage, the microstructure of cement slurry changed from "dispersed particles" to "gel network", causing the gravity of the particles to be diverted to external interfaces. In the rapid descent stage, hydrostatic pressure of the cement slurries was attributed to the pore water. But the rapid reduction in the pore size increased the capillary pressure of the pore water, causing the gravity of pore water to transfer to external interfaces via the "gel network". Finally, when the most probable pore diameter decreased to approximately 50 nm, the hydrostatic pressure of the cement slurry was reduced to zero. • This paper investigated the microstructure evolution of the cement particles. • A quantitative method was developed to test the pore structure of cement slurry. • The pore structure evolution of the cement slurry in the early stage of hydration was studied. • Three-dimensional pores of the cement slurry was obtained. • Combining the microstructure and pore structure, hydrostatic pressure descent mechanism of cement slurry was analysed. [ABSTRACT FROM AUTHOR]

Background. Previous studies have investigated the association between the use of bisphosphonates and the development of breast cancer, which presented controversial results. Thus, this meta-analysis was conducted to summarize the current evidence of the association of bisphosphonate use with breast cancer risk. Methods. A comprehensive search was conducted in PubMed, ISI Web of Knowledge, the Cochrane Library, and Embase from inception to March 2019 by two researches, who independently selected trials, retrieved relevant data, and assessed study quality. The summary relative risk (RR) for the use of bisphosphonates on the risks of developing breast cancer was calculated using a random-effect model. Results. The present meta-analysis, which included four case-control studies, involving 55052 breast cancer cases, and seven retrospective cohort studies, involving 14641 breast cancer cases, assessed the effect of bisphosphonates on breast cancer risk. The random-effect model meta-analysis found a reduced risk of breast cancer with exposure to bisphosphonates with pooled RR of 0.87 (95% confidence interval [CI]: 0.80 to 0.94). The short-term use of bisphosphonates (<1 year) did not render significant alteration (RR = 0.92 , 95% CI: 0.82 to 1.03), while a significant 26% risk reduction of breast cancer was noted with long-term use (>1 year) (RR = 0.74 , 95% CI: 0.62 to 0.90). A protective effect of bisphosphonates was shown in contralateral breast cancer (RR = 0.41 , 95% CI: 0.20 to 0.84). In terms of the type of bisphosphonates, a significant inverse relationship was noted for etidronate, with pooled RR of 0.87 (95% CI: 0.80 to 0.96). Conclusion. This meta-analysis suggested that the use of bisphosphonates was associated with reduced risk of breast cancer, including contralateral breast cancer. Compared to other types of bisphosphonates, only etidronate showed a significant inverse relationship. Additionally, the long-term use (>1 year) of bisphosphonates was more significant in lowering breast cancer risk. Further randomized controlled trials are needed to verify this association. This trial is registered with PROSPERO (registration number: CRD42018105024) (registered on 29 August 2018). [ABSTRACT FROM AUTHOR]

Bulk homogeneous polyelectrolyte complex hydrogels (PCH) are difficult to prepare due to the flocculation effect between polyelectrolytes with opposite charges. Herein, novel chitosan/sodium polyacrylate (PAAS) polyelectrolyte complex hydrogels (CPG) were fabricated successfully by cross-linking chitosan and PAAS with epichlorohydrin (ECH) through inhibiting protonation effect of chitosan in alkali/urea aqueous solution. The swelling behaviors of CPG were studied systematically in different solutions. The equilibrium swelling ratio of chitosan hydrogel in water increased dramatically from 46.3 to 404.8 g/g by the introduction of PAAS. CPG exhibited different swelling ratios towards different pH solutions, physiological solutions and salt solutions with different concentrations, showing obvious smart responsive properties. Moreover, CPG hydrogels exhibited relatively high compressive strength, good biocompatibility and in vitro biodegradability. Therefore, this work provided a novel PCH and shed light on the fabrication of other PCH, showing potential applications in the fields of agriculture, foods, tissue engineering and drug delivery. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most common type of primary brain tumour in adults, and presents a very low survival rate. Isocitrate dehydrogenase (IDH)1/2 mutations have been found in ~12% of glioblastomas and are associated with long-term GBM survival. However, the risk factors that influence the prognosis of IDH-wild type GBM remain unclear. Hypoxia-inducible factor (HIF)-1α, an important oxygen-regulated transcription factor, has been demonstrated to serve a crucial role in tumour development and to be associated with a poor prognosis. In addition, caveolin-1 (CAV1) is a plasma membrane organizing protein, the expression of which can also be regulated by a hypoxic microenvironment. The present study therefore aimed to examine the expression levels of HIF-1α and CAV1, and their association with GBM prognosis. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to analyse the expression levels of HIF-1α and CAV1 in paired GBM tumour and adjacent non-tumour tissues. Immunohistochemistry was used to analyse the expression of the two proteins in paraffin-embedded tissues obtained from 42 patients with IDH-wild type GBM. Statistical analyses were performed to examine the correlation between HIF-1α and CAV1 expression and patient prognosis. The results revealed hat the expression levels of HIF-1α and CAV1 were upregulated in IDH-wild type GBM tissues compared to their paired non-tumour tissues (P<0.001). The expression of CAV1 was significantly correlated with high HIF-1α expression (P<0.01). In addition, overexpression of HIF-1α and CAV1 was markedly associated with a poor prognosis (P<0.001). In conclusion, HIF-1α and CAV1 may represent potential biomarkers for IDH-wild type GBM prognosis and potential targets for the development of therapies extending GBM survival. [ABSTRACT FROM AUTHOR]

Brain-type glycogen phosphorylase (PYGB) is an enzyme that metabolizes glycogen, whose function is to provide energy for an organism in an emergency state. The present study purposed to investigate the role and mechanism of PYGB silencing on the growth and apoptosis of prostate cancer cells. A cell counting kit-8 assay and flow cytometry were performed to determine the cell viability, apoptosis and reactive oxygen species (ROS) content, respectively. Colorimetry was performed to analyze the activity of caspase-3. Western blotting and reverse transcription-quantitative polymerase chain reaction were used to evaluate the associated mRNA and protein expression levels. The results revealed that PYGB was upregulated in prostate cancer tissues and was associated with disease progression. In addition, PYGB silencing suppressed the cell viability of PC3 cells. PYGB silencing promoted apoptosis of PC3 cells via the regulation of the expression levels of cleaved-poly (adenosine diphosphate-ribose) polymerase, cleaved-caspase-3, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein. PYGB silencing increased the ROS content in PC3 cells, and affected nuclear factor (NF)-κB/nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling pathways in PC3 cells. In conclusion, PYGB silencing suppressed the growth and promoted the apoptosis of prostate cancer cells by affecting the NF-κB/Nrf2 signaling pathway. The present study provided evidence that may lead to the development of a potential therapeutic strategy for prostate cancer. [ABSTRACT FROM AUTHOR]

Hg2+ is a serious environmental contaminant that can cause severe damage to the immune and nervous systems, and Hg2+ monitoring is critical. Herein, we report a novel, simple, and sensitive Hg2+ sensor based on the enhanced peroxidase‐like activity of chitosan–gold nanoparticles (CS‐AuNPs). The peroxidase‐like activity of the CS‐AuNPs can be markedly enhanced by Hg2+ as seen by the deeper color and increased absorbance at 652 nm. This improved catalytic ability was used to develop a sensitive and selective colorimetric sensor for Hg2+ detection. The limit of detection via the absorption spectra is as low as 0.02 μM. The mechanism underlying the enhanced catalytic ability is discussed. This approach is label‐free, simple, and offers detection with the naked eye. Thus, it has potential applications for the detection of Hg2+ in environmental and food samples. [ABSTRACT FROM AUTHOR]

All-trans-retinoic acid (RA) inhibits adipogenesis in established preadipocyte cell lines. Dosing pharmacological amounts of RA reduces weight gain in mice fed a high-fat diet, i.e. counteracts diet-induced obesity (DIO). The aldehyde dehydrogenase Raldh1 (Aldh1a1) functions as one of three enzymes that converts the retinol metabolite retinal into RA, and one of many proteins that contribute to RA homeostasis. Female Raldh1-ablated mice resist DIO. This phenotype contrasts with ablations of other enzymes and binding-proteins that maintain RA homeostasis, which gain adiposity. The phenotype observed prompted the conclusion that loss of Raldh1 causes an increase in adipose tissue retinal, and therefore, retinal functions independently of RA to prevent DIO. A second deduction proposed that low nM concentrations of RA stimulate adipogenesis, in contrast to higher concentrations. Using peer-reviewed LC/MS/MS assays developed and validated for quantifying tissue RA and retinal, we show that endogenous retinal and RA concentrations in adipose tissues from Raldh1-null mice do not correlate with the phenotype. Moreover, male Raldh1-null mice resist weight gain regardless of dietary fat content. Resistance to weight gain occurs during adolescence in both sexes. We show that RA concentrations as low as 1 nM, i.e. in the sub-physiological range, impair adipogenesis of embryonic fibroblasts from wild-type mice. Embryonic fibroblasts from Raldh1-null mice resist differentiating into adipocytes, but retain ability to generate RA. These fibroblasts remain sensitive to an RA receptor pan-agonist, and are not affected by an RA receptor pan-antagonist. Thus, the data do not support the hypothesis that retinal itself represses weight gain and adipogenesis independently of RA. Instead, the data indicate that Raldh1 functions as a retinal and atRA-independent promoter of adiposity during adolescence, and enhances adiposity through pre-adipocyte cell autonomous actions. [ABSTRACT FROM AUTHOR]

This study employs the mechanical vibration and acoustic waves of a hydraulic support tail beam for an accurate and fast coal-rock recognition. The study proposes a diagnosis method based on bimodal deep learning and Hilbert-Huang transform. The bimodal deep neural networks (DNN) adopt bimodal learning and transfer learning. The bimodal learning method attempts to learn joint representation by considering acceleration and sound pressure modalities, which both contribute to coal-rock recognition. The transfer learning method solves the problem regarding DNN, in which a large number of labeled training samples are necessary to optimize the parameters while the labeled training sample is limited. A suitable installation location for sensors is determined in recognizing coal-rock. The extraction features of acceleration and sound pressure signals are combined and effective combination features are selected. Bimodal DNN consists of two deep belief networks (DBN), each DBN model is trained with related samples, and the parameters of the pretrained DBNs are transferred to the final recognition model. Then the parameters of the proposed model are continuously optimized by pretraining and fine-tuning. Finally, the comparison of experimental results demonstrates the superiority of the proposed method in terms of recognition accuracy. [ABSTRACT FROM AUTHOR]

Summary Although all- trans -retinoic acid (atRA) is a key regulator of intestinal immunity, its role in colorectal cancer (CRC) is unknown. We found that mice with colitis-associated CRC had a marked deficiency in colonic atRA due to alterations in atRA metabolism mediated by microbiota-induced intestinal inflammation. Human ulcerative colitis (UC), UC-associated CRC, and sporadic CRC specimens have similar alterations in atRA metabolic enzymes, consistent with reduced colonic atRA. Inhibition of atRA signaling promoted tumorigenesis, whereas atRA supplementation reduced tumor burden. The benefit of atRA treatment was mediated by cytotoxic CD8 + T cells, which were activated due to MHCI upregulation on tumor cells. Consistent with these findings, increased colonic expression of the atRA-catabolizing enzyme, CYP26A1, correlated with reduced frequencies of tumoral cytotoxic CD8 + T cells and with worse disease prognosis in human CRC. These results reveal a mechanism by which microbiota drive colon carcinogenesis and highlight atRA metabolism as a therapeutic target for CRC. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) mainly infects neonatal pigs, resulting in significant morbidity and mortality. Owing to problems such as long periods of virus shedding, existing vaccines cannot provide complete protection from PEDV infection. The PEDV genome encodes two polyprotein precursors required for genome replication and transcription. Each polyprotein undergoes extensive proteolytic processing, resulting in functional subunits. This process is mainly mediated by its genome-encoded main protease, which is an attractive target for antiviral drug design. In this study, the main protease of Porcine epidemic diarrhea virus in complex with a Michael acceptor was crystallized. The complex crystals diffracted to 2.5 Å resolution and belonged to space group R3, with unit-cell parameters a = 175.3, b = 175.3, c = 58.7 Å. Two molecules were identified per asymmetric unit. [ABSTRACT FROM AUTHOR]

Human coronavirus HKU1 (HCoV-HKU1), which mainly causes acute self-limited respiratory-tract infections, belongs to group A of the Betacoronavirus genus. Coronavirus genomes encode 16 nonstructural proteins (nsp1-16), which assemble into a large replication-transcription complex mediating virus propagation. Nonstructural protein 9, which binds to the single-stranded DNA/RNA, has been shown to be indispensible for viral replication. Interestingly, a functional mutant (N60K) of nsp9 was identified to compensate for a 6 nt insertion mutation of the 3′-untranslated region (UTR), which is critical for viral RNA synthesis. It has been proposed that the N60K mutation may cause certain conformational changes of nsp9 to rescue the defective insertion mutant. To further investigate the underlying structural mechanism, the N60K mutant of nsp9 from HCoV-HKU1 was successfully crystallized in this study. The crystals diffracted to 2.6 Å resolution and belonged to space group P212121, with unit-cell parameters a = 31.9, b = 85.0, c = 95.0 Å. Two molecules were identified per asymmetric unit. [ABSTRACT FROM AUTHOR]

Human coronavirus NL63 mainly infects younger children and causes cough, fever, rhinorrhoea, bronchiolitis and croup. It encodes two polyprotein precursors required for genome replication and transcription. Each polyprotein undergoes extensive proteolytic processing, resulting in functional subunits. This process is mainly mediated by its genome-encoded main protease, which is an attractive target for antiviral drug design. In this study, the main protease of human coronavirus NL63 was crystallized in complex with a Michael acceptor. The complex crystals diffracted to 2.85 Å resolution and belonged to space group P41212, with unit-cell parameters a = b = 87.2, c = 212.1 Å. Two molecules were identified per asymmetric unit. [ABSTRACT FROM AUTHOR]

Objective To study the application of coronary endarterectomy (CE) in coronary artery bypass graft (CABG), and to evaluate the effect of CE plus CABG on patients with chronic total occlusion (CTO) combined with diffuse distal atherosclerosis. Methods Thirty one patients, who underwent coronary endarterectomy in our institution between October 2009 and October 2012, were reviewed retrospectively and compared the control group with 31 patients of their age, sex, LV function, and angina class. Results Among the 31 patients, 27 patients underwent one, 4 patient underwent two coronary arteries endarterectomized. Of all these 35 total endarterectomies, 13 (37%) were at left anterior descending artery, 3(9%) were at branches of the circumflex artery, and 19 (54%) involved the right coronary artery. There was no statistical difference between two groups in clinical parameters including aorta cross time, cardiopulmonary bypass time, graft runoff, pulsation index and mechanism ventilate time (P > 0.05). There was no perioperative myocardial infarctions in CE group nor in control group. All patients were followed up and no recurrent angina were present in CE group. In CE group, one patient died of fungal pneumonia and heart failure half a year after operation. Conclusion In current cardiac surgical practice, coronary endarterectomy is an indispensable adjunct to CABG. The operative mortality and major morbidity were comparable or similar to coronary artery bypass grafting, but its short-term and medium-term results were more favorable than to CABG. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) is an autoimmune disease that attacks anagen hair follicles. Gene array in graft-induced C3H/HeJ mice revealed that genes involved in retinoic acid (RA) synthesis were increased, whereas RA degradation genes were decreased in AA compared with sham controls. This was confirmed by immunohistochemistry in biopsies from patients with AA and both mouse and rat AA models. RA levels were also increased in C3H/HeJ mice with AA. C3H/HeJ mice were fed a purified diet containing one of the four levels of dietary vitamin A or an unpurified diet 2 weeks before grafting and disease progression followed. High vitamin A accelerated AA, whereas mice that were not fed vitamin A had more severe disease by the end of the study. More hair follicles were in anagen in mice fed high vitamin A. Both the number and localization of granzyme B-positive cells were altered by vitamin A. IFNγ was also the lowest and IL13 highest in mice fed high vitamin A. Other cytokines were reduced and chemokines increased as the disease progressed, but no additional effects of vitamin A were seen. Combined, these results suggest that vitamin A regulates both the hair cycle and immune response to alter the progression of AA. [ABSTRACT FROM AUTHOR]

While vitamin A has been implicated in host resistance to infectious disease, little is known about the role of vitamin A and its active metabolite, retinoic acid (RA) in host defenses against cancer. Here, we show that local RA production within the tumor microenvironment (TME) is increased up to 5-fold as compared with naïve surrounding tissue, with a commensurate increase in RA signaling to regionally infiltrating tumor-reactive T cells. Conditional disruption of RA signaling in CD8+ T cells using a dominant negative retinoic acid receptor a (dnRARα) established that RA signaling is required for tumor-specific CD8+ T-cell expansion/accumulation and protective antitumor immunity. In vivo analysis of antigen-specific CD8+ T-cell responses revealed that early Tcell expansion was RA-independent; however, late T-cell expansion and clonal accumulation was suppressed strongly in the absence of RA signaling. Our findings indicate that RA function is essential for the survival of tumor-reactive CD8+ T cells within the TME. [ABSTRACT FROM AUTHOR]