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In this study, SnO 2 –ZnO nanofibers were synthesized by electrospinning and heat treatment. In addition, their structural, morphological, and optical properties were investigated by X-ray diffraction (XRD), SEM, transmission electron microscopy (TEM), and ultraviolet–visible spectrophotometry. Results revealed that the composites exhibit a distinctive nanofibrous shape, which is consistent with that of SnO 2 –ZnO after high-temperature calcination. Furthermore, the sensing response was optimized by the variation of Sn:Zn ratios and the Au sputtering time. Hence, the heteronanostructure of the SnO 2 –ZnO composite nanofiber film is doped with Au nanoparticles to investigate the resulting sensitivity to different gases. In addition, the gas-sensing mechanism was discussed. • An Au-doped SnO2–ZnO composite-based gas sensor was developed by electrospinning and heat treatment. • The SnO2–ZnOgas sensor responses to ethanol, methanol, acetic acid, acetone, and CO were observed and suitable for various gas-sensing applications. • The SnO2–ZnO composite nanofiber film exhibited an optimum sensing response to a Sn:Zn ratio of 1:0.5 with a Au sputtering time of 30 s. [ABSTRACT FROM AUTHOR]

In this study, the thermal conductivity and thermal boundary resistance (TBR) of Bi2Te3 nanofilms with different interfacial defects were investigated using nonequilibrium molecular dynamics simulations, and the effects of temperature, defects (step junctions and grooves), and interfaces (amorphous and telluride) were assessed. The results show a strong temperature dependence of the thermal conductivity for Bi2Te3 nanofilms with an ideal structure; moreover, as the height of step-junction defects increased, the thermal conductivity decreased, exhibiting a linear dependency. In addition, the thermal conductivity gradually decreased by 36%–40% as the width of the interface defects increased. We also verified the self-assembly mechanism for nanoscale Bi2Te3 and found that the Bi2Te3–Te interface induces strong phonon scattering. In addition, the TBR decreased as the width of the amorphous or Te interface increased. Thus, interfacial defects in Bi2Te3 nanofilms affect the thermal conductivity and TBR. The results of this study may be useful for optimizing Bi2Te3 thermoelectric devices in the future. [ABSTRACT FROM AUTHOR]

Both warm- and cold-sensitive neurons are found in the lateral parabrachial nucleus (LPB), a crucial relay for skin temperature information from the spinal cord to the preoptic area. The aims of this study were to investigate the electrophysiological properties of temperature-sensitive and -insensitive neurons in brain slices, and elucidate the basic mechanisms underlying the thermosensitivity of rat LPB neurons. In warm-sensitive neurons, temperature exerted no significant effects on resting membrane potential (RMP), threshold potential, and amplitude of the afterhyperpolarizing potential. However, warming significantly increased the prepotential rates of depolarization and the inactivation rates of potassium A current (I A) in warm-sensitive neurons, which in turn shortened their interspike interval and elevated the firing rate. In contrast, temperature had no significant effects on the depolarizing prepotentials and inactivation rate of I A in temperature-insensitive neurons. Besides, in cold-sensitive neurons, cooling and warming produced membrane depolarization and hyperpolarization, respectively, and there was a strong correlation between firing rate and membrane potential thermosensitivity. Nevertheless, temperature exhibited no significant effect on the depolarizing prepotential of cold-sensitive neurons. These results suggest that LPB neuronal warm sensitivity may reside in the temperature-dependent prepotentials and I A , while neuronal cold sensitivity might be mainly due to heat-induced changes in RMP. • The primary mechanism of LPB neuronal warm sensitivity resides in the prepotential. • I A currents may contribute to the temperature-dependent prepotentials of warm-sensitive LPB neurons. • LPB neuronal cold sensitivity is primarily due to a thermally induced change in the RMP. [ABSTRACT FROM AUTHOR]

[Display omitted] • The S-NiFe PBA@NiFe in situ grown on the NF expedites electron conduction. • The Mott-Schottky heterojunctions of S-NiFe PBA@NiFe promote electron transport. • S-NiFe PBA@NiFe/NF presents outstanding OER activity in 1 M KOH electrolyte. • S-NiFe PBA@NiFe possesses low overpotential of 196.7 mV and perfect durability. Development of economical and high-efficient catalytic electrodes is a top priority for oxygen evolution reactions (OER). Non-precious metal based metal–organic frameworks (MOFs) in powder form remain a series of problems including the assistance of adhesive, poor conductivity and stability. Herein, a well-designed S-NiFe PBA@NiFe/NF composite with a unique Mott-Schottky heterojunction architecture was purposefully constructed by self-sacrificing template approach and electrodeposition. The growth of S-NiFe PBA@NiFe on NF through in situ synthesis promotes efficient electron conduction between the NF substrate and S-NiFe PBA@NiFe catalyst, leading to a stable and highly effective working state. The Mott-Schottky heterojunctions between S-NiFe PBA and NiFe-layered double hydroxides (LDH) effectively expedite electronic transmission. Consequently, S-NiFe PBA@NiFe/NF exhibits outstanding OER behavior at 1.0 M KOH, exhibiting a low Tafel slope of 39 mV dec−1 and at 10 mA cm−2, reaching an unexpectedly low overpotential of 196.7 mV. Furthermore, the S-NiFe PBA@NiFe/NF maintains long-term durability without evident performance degradation for 100 h. [ABSTRACT FROM AUTHOR]

With the development of the Internet of Things, multi-access edge computing (MEC) is widely used in industrial IoT, intelligent transport systems, and IoT data management. As a decentralized, tamper-proof, multiparty trusted ledger technology, blockchain can enhance MEC security, privacy, and automatic use of resources. However, highly redundant storage and complex consensus prevent the blockchain from being directly deployed to edge computing nodes with limited resources. Unlike existing lightweight schemes, which do not consider liberating transaction data from blocks, this paper proposes a lightweight blockchain ledger protocol for MEC networks. The novelty of this work is that the transaction data in the block is compressed into a succinct proof through the zero-knowledge proof algorithm. To reduce the storage of block data, this paper proposes the proof-of-state-transfer model in which nodes verify the correctness of the global state transfer in the block without transactions. To reduce the communication complexity of consensus, this paper proposes a lightweight consensus protocol, which reduces the communication complexity of block voting and view switching to O (n). This paper develops the prototype system of TinyLedger to experiment and evaluate the performance of the system in terms of storage, verification, throughput, and communication. Experimental results show that compared to Ethereum, TinyLedger reduces storage capacity by 98.16%, communication volume by 74.53%, and block verification time by 87%. [ABSTRACT FROM AUTHOR]

Utilizing the Comprehensive Environmental Administrative Enforcement Reform (CEAER) in China as a quasi-natural experiment, this paper has adopted 179 prefecture-level cities from July 2018 to December 2020 as research sample to assess whether the limited decentralization of environmental enforcement power can improve air quality through a time-varying difference-in-difference (DID) approach. Results show that CEAER can achieve better air quality improving effects, which can not only contribute to the decrease of daily mean values of Air Quality Index (AQI), but also contribute to the decrease of daily mean values of PM 2.5 , PM 10 , SO 2 , and CO. And this promotion is mainly achieved through the micro mechanism of raising environmental penalties strength. Further examination of the heterogeneity in terms of economic factors, city rank, pollution abatement pressure, and political constraints reveals that CEAER's policy effects are mostly insignificant in cities with higher levels of economic development and administrative rank, and positively significant in poor historical air quality cities and key environmental protection cities. These results underscore the positive effects of the limited decentralization of environmental enforcement power and provide ideas for other regions to draw on for environmental management system reform. [ABSTRACT FROM AUTHOR]

The quality and composition of strong-flavor Baijiu (SFB), a type of Chinese liquor, depends on the variety of sorghum used in fermentation. However, comprehensive in situ studies measuring the effects sorghum varieties on the fermentation are lacking and the underlying microbial mechanisms remains poorly understood. We studied the in situ fermentation of SFB by using metagenomic, metaproteomic, and metabolomic techniques across four sorghum varieties. Sensory characteristics were best for SFB made from glutinous variety Luzhouhong , followed by glutinous hybrid Jinnuoliang and Jinuoliang , and those made with non-glutinous Dongzajiao. In agreement with sensory evaluations, the volatile composition of SFB samples differed between sorghum varieties (P < 0.05). Fermentation of different sorghum varieties varied in microbial diversity, structure, volatile compounds, and physicochemical properties (pH, temperature, starch, reducing sugar, and moisture) (P < 0.05), with most changes occurring within the first 21 days. Additionally, the microbial interactions and their relationship with volatiles, as well as the physicochemical factors that govern microbial succession, differed between varieties of sorghum. The number of physicochemical factors affecting bacterial communities outweighed those affecting fungal communities, suggesting that bacteria were less resilient to the brewing conditions. This correlates with the finding that bacteria play a major role in the differences in microbial communities and metabolic functions during fermentation with the different varieties of sorghum. Metagenomic function analysis revealed differences in amino acid and carbohydrate metabolism between sorghum varieties throughout most of the brewing process. Metaproteomics further indicated most differential proteins were found in these two pathways, related to differences in volatiles between sorghum varieties of Baijiu and originating from Lactobacillus. These results provide insight into the microbial principles underlying Baijiu production and can be used to improve the quality of Baijiu by selecting the appropriate raw materials and optimizing fermentation parameters. • Baijiu fermentation was performed using different sorghum varieties. • Microbial succession affected volatile formation differently in sorghum varieties. • Bacteria caused more differences in communities and functions than fungi. • Sorghum variety and fermentation time interact to affect volatiles and bacteria. [ABSTRACT FROM AUTHOR]

With the development of infrastructure construction in mountainous areas, the number of new extra-long tunnels is increasing. However, these tunnels often face the challenge of complex and variable surrounding rock grades, resulting in a large number of overbreak and underbreak due to the untimely adjustment of smooth blasting parameters. This study focuses on the optimization of the peripheral hole charging structure and blasting parameters for extra-long hard rock tunnels, aiming to improve the effectiveness of smooth blasting technology. The results of this study demonstrate a significant improvement in the effect of smooth blasting after implementing bidirectional polymerization blasting in the tunnel. A comparison between the bidirectional shaped charge and spaced decoupled charge blasting reveals that the former yields better results. To obtain accurate data on the tunnel section profile during excavation, a laser cross-section meter is used for measurement. Furthermore, this study quantitatively compares the optimization effect of smooth blasting parameters. The multifractal characteristics of the tunnel profile overbreak point sequences are analyzed under different smooth blasting schemes using the multifractal detrended fluctuation analysis (MF-DFA) method. It is found that both the spaced decoupled charge and the bidirectional shaped charge blasting exhibit multifractal features in the overbreak measurement point sequences. The calculation results of the multifractal features of the tunnel profile under different smooth blasting plans are in line with the actual situation. [ABSTRACT FROM AUTHOR]

The roles of cyclin-dependent kinase 6 (CDK6) in various cancers, including small cell lung carcinoma (SCLC), remain unclear. Here, 111,54 multi-center samples were investigated to determine the expression, clinical significance, and underlying mechanisms of CDK6 in 34 cancers. The area under the curve (AUC), Cox regression analysis, and the Kaplan–Meier curves were used to explore the clinical value of CDK6 in cancers. Gene set enrichment analysis and correlation analysis were performed to detect potential CDK6 mechanisms. CDK6 expression was essential in 24 cancer cell types. Abnormal CDK6 expression was observed in 14 cancer types (e.g., downregulated in breast invasive carcinoma; p < 0.05). CDK6 allowed six cancers to be distinguished from their controls (AUC > 0.750). CDK6 expression was a prognosis marker for 13 cancers (e.g., adrenocortical carcinoma; p < 0.05). CDK6 was correlated with several immune-related signaling pathways and the infiltration levels of certain immune cells (e.g., CD8+ T cells; p < 0.05). Downregulated CDK6 mRNA and protein levels were observed in SCLC (p < 0.05, SMD = − 0.90). CDK6 allowed the identification of SCLC status (AUC = 0.91) and predicted a favorable prognosis for SCLC patients (p < 0.05). CDK6 may be a novel biomarker for the prediction and prognosis of several cancers, including SCLC. [ABSTRACT FROM AUTHOR]

Abstract Carbapenemase-producing Klebsiella pneumoniae has emerged and spread widely throughout the world. The mechanisms involved remain unclear. To provide insight, five plasmids were obtained from carbapenemase-producing K. pneumoniae clinical isolates. The five sequences were acquired, aligned and analyzed. In addition to the bla KPC-2 gene, which encodes beta lactamase, essentially all the plasmids contained a putative anti-restriction protein-encoding gene, KlcA HS. The KlcA HS gene was found in 98.2% of the bla KPC-2 -positive, imipenem-resistant K. pneumoniae clinical isolates and in <1% of the bla KPC-2 -negative control group. A searched of the GenBank database indicated that KlcA HS was mainly submitted by Chinese investigators beginning in 2010. Seventeen different KlcA amino acid sequences were found in the database using the restricting words: KlcA and Klebsiella pneumoniae. These sequences were used to generate a phylogenetic tree via MEGA6 software, revealing a distant evolutionary relationship between KlcA HS and other KlcAs. The secondary structure of KlcA HS , predicted with PROMALS3D software, exhibited highly conserved α-helices and β-strands. KlcA HS expressed anti-restriction activity in vivo. In summary, KlcA HS genes are ubiquitous in bla KPC-2 -positive Klebsiella pneumoniae clinical isolates collected at Huashan Hospital, China. The KlcA HS protein possesses a secondary structure similar to that exhibited by anti-restriction proteins and displays anti-restriction activity. As such, KlcA HS is a probable factor in the accelerated spread of bla KPC-2 and carbapenem-resistance among clinical, K. pneumoniae isolates. Highlights • The exact mechanism(s) underlying dissemination of bla KPC-2 in K. pneumoniae is presently unclear. • Multiple factors are implicated in the process. • We report that all five plasmids extracted from bla KPC-2 positive K. pneumoniae clinical isolates harbored the KlcA HS gene. • KlcA HS genes are abundant in bla KPC-2 -positive isolates, they rare in bla KPC-2 negative K. pneumoniae isolates. • KlcA HS is a significant factor in the spread of bla KPC-2 among K. pneumoniae clinical isolates. • This study reveals a novel insight into the enhanced dissemination of the bla KPC-2 gene in hospitals. [ABSTRACT FROM AUTHOR]

A facile solid-phase hot-pressing method was applied to prepare bimetallic phosphides on carbon cloth without binder as efficient electrocatalysts for water splitting. • A new solid-phase hot-pressing method is applied to synthesize MOF-based composite on substrate without any binder. • POMs coupled with ZIFs precursors can be carbonized to prepare phosphide coated with N-doped porous carbon. • CoP/MoP@NC can reach an ultra-high current density over 1000 mA cm-2 for water splitting. • The synergistic effect of CoP, MoP and the hydroxide/oxide layer ensures the enhanced performance and stability. Rational design of electrocatalyst with high performance for both hydrogen and oxygen evolution reaction is attracting considerable attention in recent years. However, most electrocatalysts are powders and require to deposit on conductive substrates with binders, leading to complicated steps and hindering the improvement of long-term stability. This work exhibits a solid-phase hot-pressing method to prepare polyoxometalates based zeolitic imidazolate frameworks (POMs-ZIFs) precursor on carbon cloth (CC) rapidly and mildly. After phosphidation treatment, nitrogen-doped graphitic carbon layers coated phosphide on CC (CoP/MoP@NC/CC) is synthesized. CoP/MoP@NC/CC has excellent electrocatalytic performance for water splitting due to the synergistic effect of CoP, MoP and as-formed oxide/hydroxide layers. It shows the low overpotentials of 94 mV for HER and 270 mV for OER at the current density of 10 mA cm−2 in alkaline medium, which is superior to most of the reported phosphide-based electrocatalysts. Notably, the ultra-high current density of 1000 mA cm−2 can be reached at the overpotentials of only 475 mV for HER and 657 mV for OER. As both cathode and anode for overall water splitting, CoP/MoP@NC can achieve the current density of 50 mA cm−2 at the cell voltage of 1.71 V. The solid-phase hot-pressing method ensures the tight and uniform growth of the fast nucleating and stable materials on substrate and applies for more electrochemical reactions. [ABSTRACT FROM AUTHOR]

Abstract A Ni and Mo x C hybrid (Ni-Mo x C) supported on N-doped reduced graphene oxide (N-rGO) electrocatalyst with high hydrogen evolution reaction (HER) activity was prepared by ultrasonication and lyophilization. Notably, benefiting from the synergistic effect between Ni and Mo x C nanoparticles, the optimized electrocatalyst displayed excellent catalytic activity with low overpotentials of 183 mV and 216 mV for the HER at the current density 10 mA cm−2 in 1.0 M KOH and 0.5 M H 2 SO 4 solution. The stability of the electrocatalyst could be well maintained for 24 h. These results indicate that the method to prepare hybrid (Ni-Mo x C) is a simple way to produce cost-effective and high-efficient molybdenum carbide for hydrogen evolution. Highlights • Effective electrocatalysts with a Ni-Mo x C/N-rGO format were successfully prepared by a simple method. • The introduction of Ni is beneficial to the formation of γ-MoC in Ni-Mo x C/N-rGO. • Mo 2 C NPs/N-rGO improves HER activity synergistically with Ni. • The catalysts exhibit good HER activity in alkaline and acidic electrolytes. [ABSTRACT FROM AUTHOR]

Abstract Lycopodium alkaloids (LAs) are the characteristic metabolites of club mosses. Chemical differences often exist in different specimens of a single plant species collected from different geographic origins. In this study, a preliminary LC-MS detection and dereplication analyses of alkaloidal constituents of Lycopodium cernuum var. sikkimense (Müll. Hal.) C.B. Clarke (LCVS2) collected from Fujian province led to the isolation and characterization of three undescribed LAs, lycocernuskines A–C, and six known cernuane-type LAs. The known compounds were previously isolated from the same plant species (LCVS1) collected from Chongqing, and so their dereplication in LCVS2 was accomplished based on their retention times (t R) and the quasi-molecular ion peaks in the LC-MS fingerprint. Chemical structures were identified by spectroscopic methods, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. Lycocernuskines A and B are the first two examples of C-12 hydroxylated phlegmarane-type LAs bearing a nitrone residue at the quinoline ring. The isolates were evaluated for their anti-AChE and neuroprotective effects. Graphical abstract LC-MS method was applied to the isolation and dereplication of Lycopodium alkaloids (LAs) from samples of the same Lycopodiaceae species (Lycopodium cernuum var. sikkimense) collected in two different locations. Three undescribed LAs were thereafter obtained and characterized. Lycocernuskines A (1) and B represent the first two examples of C-12 hydroxylated phlegmarane-type LAs bearing a nitrone residue at the quinoline ring. Image 1 Highlights • LC-MS guided isolation and dereplication of Lycopodium alkaloids (LAs) was applied. • Three undescribed LAs were obtained from Lycopodium cernuum var. sikkimense. • Lycocernuskines A and B are unusual nitrone-containing 12-hydroxy-phlegmarane LAs. • The absolute configurations of lycocernuskines A and B were determined. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • An UHPLC-MS/MS method for simultaneous analysis of alkylation DNA adducts in DNA, RNA, cell contents were established. • Established a DNA pretreatment method for simultaneously acquired multiple DNA adducts within 4 hours. • First report of the content relationships of 7MeG, 1MeG and 1MeG after exposure to genotoxic reagents. • First report that cells revealed different DNA adduct formation characteristics after exposure to genotoxic reagents. Abstract A rapid, sensitive and wide coverage ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method has been developed and validated for the simultaneous quantitation of 14 alkylation DNA adducts in cell genomic DNA, RNA and cell contents isolated from the in vitro cultured human kidney cell line 293 T and the human liver cell line L02 exposed to 3 genotoxic reagents: N -methyl -N- nitrosourea (MNU), methyl methanesulfonate (MMS) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). After exposure, DNA was isolated and directly hydrolysed under acid conditions or digested by enzymes to obtain the hydrolysates containing DNA alkylation adducts followed by optimization of the pretreatment method and chromatographic separation conditions. Quantification was performed on a Waters ACQUITY UPLC BEH Amide column (1.7 μm, 2.1 × 150 mm) using an electrospray ionization (ESI) source in positive mode by selective reaction monitoring (SRM) at the precursor to product ion transitions of 14 analytes. The method showed selectivity, good linearity (r＞0.9950), accuracy (82.1%–115%), and intra-day (RSD%＜14%) and inter-day (RSD%＜15%) precision for 14 analytes. The recoveries of two pretreatment methods were all more than 50.5%, and no relative matrix effects were observed. Additionally, the samples were stable after short-term storage at 20 ℃ for 2 h, at 4 ℃ for 48 h or one cycle of freeze-thaw at −80 ℃. The established UHPLC-MS/MS method was used to evaluate the changes in alkylation DNA adducts and epigenetic modification-related methylcytosine after exposure to genotoxic reagents. For the first time, the results demonstrated that 3 genotoxic reagents induced different total amounts of adducts in the following sequence: MMS ＞ NNK ＞ MNU, and showed significant differences in the ratios of 7MeG to 1MeA and 1MeG to 1MeA in the 293 T cell model. Meanwhile, 293 T and L02 cells revealed significantly different DNA adduct formation characteristics in the contents of 1MeG and 1MeA. The DNA adduct formation relationships between DNA, RNA, and cell contents were probed to predict cancer risk and potential genotoxic exposure. This approach could be used to investigate the DNA adducts, their formation and the relationship to the mutagenicity or carcinogenicity of genotoxic reagents in future studies. [ABSTRACT FROM AUTHOR]

The potential of the positron-emitting zirconium-89 (89Zr) (t 1/2 = 78.4 h) has been recently reported for immune positron emission tomography (immunoPET) radioimmunoconjugates design. In our work, we explored the optimized preparation of [89Zr]Zr-DFO-nimotuzumab, and evaluated 89Zr-labeled monoclonal antibody (mAb) construct for targeted imaging of epidermal growth factor receptor (EGFR) overexpressed in glioma. To optimize the radiolabeling efficiency of 89Zr with DFO-nimotuzumab, multiple immunoconjugates and radiolabeling were performed. Radiolabeling yield, radiochemical purity, stability, and activity assay were investigated to characterize [89Zr]Zr-DFO-nimotuzumab for chemical and biological integrity. The in vivo behavior of this tracer was studied in mice bearing subcutaneous U87MG (EGFR-positive) tumors received a 3.5 ± 0.2 MBq/dose using PET/CT imaging. One group mice bearing subcutaneous U87MG (EGFR-positive) tumors received [89Zr]Zr-DFO-nimotuzumab (3.5 ± 0.2 MBq, ~3 μg) (nonblocking) for immunoPET; the other group had 30 μg predose (blocking) of cold nimotuzumab 24 h prior to [89Zr]Zr-DFO-nimotuzumab. [89Zr]Zr-DFO-nimotuzumab was prepared with high radiochemical yield (>90%), radiochemical purity (>99%), and specific activity (115 ± 0.8 MBq/mg). In vitro validation showed that [89Zr]Zr-DFO-nimotuzumab had an initial immunoreactive fraction of 0.99 ± 0.05 and remained active for up to 5 days. A biodistribution study revealed excellent stability of [89Zr]Zr-DFO-nimotuzumab in vivo compared with 89Zr as a bone seeker. High uptake in the liver and heart and modest penetration in the brain were observed, with no significant accumulation of activity in other organs. ImmunoPET studies also indicated prominent image contrast that remarkably high uptake up to ~20%ID/g for nonblocking and ~2%ID/g for blocking in tumor between 12 and 120 h after administration. These studies developed a radiopharmaceutical [89Zr]Zr-DFO-nimotuzumab with optimized synthesis. The potential utility of [89Zr]Zr-DFO-nimotuzumab in assessing EGFR status in glioma was demonstrated in this study. Unlabelled Image [ABSTRACT FROM AUTHOR]

Polysaccharides extracted from Morchella angusticepes Peck (PMEP) were chemically modified to obtain sulfated, carboxymethylated, and acetyled derivatives. Results showed that the acetyled derivatives with the degree of substitution (0.40 ± 0.07) exerted higher antioxidant ability than native polysaccharides, demonstrating inhibitory effects on growth of human hepatoma cells (EC50 = 0.710 ± 0.002 mg/mL) and human colon cancer cells (EC50 = 1.229 ± 0.008 mg/mL). It indicated that the acetylation was a favorable way to enhance the bioactivities of PMEP. Practical Application: Polysaccharides extracted from Morchella angusticepes Peck (PMEP) have many health‐promoting properties. Chemical modifications could improve the bioactivities of polysaccharides. We demonstrated that acetylation enhanced the cellular antioxidant and antiproliferative activities of PMEP. The results support further research that explores clinical utility, and may justify ex vivo and in vivo designs toward that end. [ABSTRACT FROM AUTHOR]

Abstract Single crystalline PbTe samples are prepared by the Pb-flux method according to the stoichiometric ratio of Pb 1+ x Te (x = 1.5, 2.0, 2.5, and 3.0). Experimental results show that all the samples exhibit n-type conductivity. The order of magnitude for carrier concentration is 1019, which is one order of magnitude higher than that in pure n-type PbTe sample (2.56 × 1018 cm−3). The highest power factor reaches 2.07 × 10−3 W m−1 K−2 at 420 K for the sample with x = 1.5, which is an approximately 30% enhancement compared with the polycrystalline sample (1.59 × 10−3 W m−1 K−2). In a theoretical study on the PbTe system, Te vacancy (V Te) is preferentially formed under the Pb-rich condition. To further understand the effect of V Te on the electrical performance of PbTe thermoelectric material, the electronic structures of PbTe with V Te are determined by first principle calculations. Theoretical calculations reveal that V Te can modify the electronic density of states by introducing resonant level, which can increase the number of carrier pockets. Consequently, carrier concentration has increased remarkably. In this study, a Pb-flux method for synthetizing single crystalline PbTe thermoelectric material is convenient and low cost, and it has potential for mass production in commercial applications. Highlights • Single crystalline PbTe samples were prepared by the Pb-flux method. • Carrier concentration was improved significantly. • Power factor was enhanced significantly compared with polycrystalline PbTe. • Effect of V Te on electrical performance was investigated by first principle. [ABSTRACT FROM AUTHOR]

Highlights • A mixed integer linear model is developed to optimize multi-period tram timetables. • Priorities of improving tram operational efficiency and timetable adherence are considered. • Arterial signal timings are resynchronized when optimizing scheduled tram trajectories. • Tram performance is improved without sacrificing vehicular mobility. Abstract Modern trams run on exclusive rail lanes along urban streets, but they usually share the right of way with general traffic at intersections and often get interrupted by traffic signals. To improve tram operation reliability, this paper develops a methodology to optimize a multi-period tram timetable by simultaneously adjusting bidirectional scheduled tram trajectories and traffic signal timings. The objective balances the operational priorities of minimizing tram running time and maximizing timetable adherence. The scheduled trajectories depict tram movements along the roads and dwell processes at stations. Arterial signal timings are resynchronized to favor tram movements. The proposed methodology was evaluated in a simulation of a real-world tram line. Compared with a traditional approach, the proposed methodology reduced tram running time, number of stops at intersections and schedule delay by 11.1%, 82.4% and 37.5%, respectively. The impact on general traffic could be assumed neutral since cycle lengths, green splits and vehicular bandwidths were kept unchanged. [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance As recorded in traditional Chinese medicine (TCM) theory, Genkwa Flos (YH) and Glycyrrhizae Radix et Rhizoma (GC) compose one herbal pair of the so-called "eighteen incompatible medicaments", which indicate pairs of herbs that are mutually incompatible and that theoretically should not be applied simultaneously. However, the theory has been called into question due to a lack of evidence. Aims of study In this study, the incompatibility of YH and GC was investigated based on an assessment of the toxic effects of their combination by traditional safety methods and a modern metabonomic approach. Materials and methods Sprague-Dawley rats were used to evaluate the subacute toxicity of YH and YH-GC. The serum, urine, and several tissues were collected for biochemical analysis, histopathological examination, and metabonomic analysis. Results Rats exposed to a dose of 1.0 g/kg YH (3 times of the Chinese Pharmacopoeia maximum dose) exhibited toxicity of the heart, liver, kidney and testes, and rats exposed to a YH-GC combination (1.0 g/kg YH + 1.0 g/kg GC) exhibited similar hepatotoxicity, which aggravated renal and reproductive toxicity. Following this, a metabonomic study tentatively identified 14 potential biomarkers in the YH group and 10 potential biomarkers in the YH-GC group, and metabolic pathways were then constructed. YH disturbed the pathways of glycerophospholipid metabolism, primary bile acid biosynthesis, and sphingolipid metabolism, while YH-GC combination induced disruptions in phenylalanine, tyrosine and tryptophan biosynthesis, tyrosine metabolism, and glycerophospholipid metabolism. Conclusion The toxicities of YH and YH-GC combination above the Chinese Pharmacopoeia dose were obvious but different. Metabonomics combined with biochemical and histopathological methods can be applied to elucidate the toxicity mechanism of the YH-GC combination that caused liver, kidney and reproductive injuries in rats. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Abstract To improve the mechanical properties of high-entropy alloys (HEAs) and expand the application range of metastable engineering, the NbZrTiTa alloy was researched. The results show that this alloy exhibits uniform element distribution and a metastable single-phase body-centered cubic (BCC) structure. During loading, element diffusion occurs, and then the TiZr-rich and TaNb-rich regions form. The increased Ti and Zr content reduces the stability of the BCC structure and leads to in-situ structure transformation in the TiZr-rich region. Element diffusion and structure transformation improve ductility by absorbing the loading work and releasing internal stresses. Furthermore, interface strengthening caused by the formation of the dual-phase region and the coherent nano-precipitation due to the compositional fluctuations together enhance the strength. The co-contribution of various metastable-induced strengthening and toughening mechanisms distinguishes the strength and ductility of the single-phase NbZrTiTa HEA from those of all the reported refractory systems. More importantly, the successful utilization of the novel metastable engineering induced by element diffusion in single-phase HEA provides a useful guide to design HEAs and other structural materials. Graphical abstract Unlabelled Image Highlights • A novel metastable engineering is utilized in single-phase high-entropy alloy to overcome the strength-ductility trade-off. • Transformation-induced plasticity effect is stimulated by element diffusion and the in-situ formation of dual-phase region. • Structure transformation and coherent nano-precipitation distinguish the mechanical property of NbZrTiTa high-entropy alloy. [ABSTRACT FROM AUTHOR]

Abstract In PbTe system, Pb vacancies (V Pb) are preferentially formed compared with other intrinsic point defects (anti-sites Te Pb and interstitials Te i) under the Te-rich condition. In order to explore the effect of V Pb on electrical transport properties of PbTe thermoelectric material, the electronic structures of PbTe with V Pb are determined by the first principle calculations. Theoretical calculations reveal that the V Pb can modify the band structure near the Fermi level, which can increase the number of carrier pockets thus increase the carrier concentration. Based on the calculated results, single crystalline PbTe samples with V Pb have been prepared by Te-flux method according to the stoichiometric ratio of PbTe 1+ x (x = 2.0, 2.5, 3.0 and 3.5). The experimental results show that carrier concentration is optimized significantly by tuning Te-flux content, and it varies from 2.94 × 1018 to 8.01 × 1018 cm−3. The highest electrical conductivity reaches 3.1 × 104 S m−1 at 300 K for x = 3.5. A large Seebeck coefficient of 562 μV/K is obtained at 480 K for x = 2.0. Due to the synergistic effect of the Seebeck coefficient and the electrical conductivity, the highest power factor of 3.17 × 10−3 W m−1 K−2 is achieved at 450 K for x = 3.0. Highlights • Single crystalline PbTe samples were prepared by Te-flux method. • The effect of V Pb on the electrical transport properties was investigated by first principle. • The V Pb can modify the electronic density of states and increase the carrier concentration. • The power factor was enhanced remarkably compared with the polycrystalline PbTe. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of estimating the angular velocity given noisy attitude measurements for attitude control in small satellites. Based on contraction analysis, a set of global exponentially convergent observers, namely, reduced-order, complete-order, and synchronized observers is designed. Simulations and experimental results are presented to illustrate their performance. [ABSTRACT FROM AUTHOR]

In this paper, the through-plane and in-plane effective transport properties, including permeability, diffusivity and thermal conductivity, of the perforated gas diffusion layer (GDL) are predicted using multiple-relaxation-time (MRT) lattice Boltzmann method (LBM) based on stochastic reconstructed microstructures. When predicting effective thermal conductivities of GDL, the effect of anisotropic conductive property of fibers is considered. The effective transport properties of dry perforated GDL are fitted as a function of perforation diameter and porosity. It is found that the permeability and effective diffusivity of GDL increase with perforation diameter and porosity while the effective thermal conductivity decreases. The two-phase LBM is adopted to simulate water distributions in perforated GDLs, and dependences of effective transport properties on saturation are then obtained. The results show that: the existence of the perforation significantly affects the water transport in hydrophobic perforated GDLs if its diameter is larger than the average pore size of GDL. The effective permeability and diffusivity of GDL decrease while effective thermal conductivity increases with saturation. The effective transport properties of perforated GDLs change less significantly with saturation than those of non-perforated GDL if the water droplet intruding into the perforation is displaced, while change more rapidly with saturation if the water droplet remains inside the perforation. [ABSTRACT FROM AUTHOR]

In many sensing and catalytic applications, the target molecule is required to be carried in an effective manner in a specific condition. Metal-organic frameworks (MOFs) have high porosity, large surface area, and tunable functionality and are promising carriers for such purposes. Current approaches to detect Tb3+ and reduce 4-nitrophenol (4-NP) are based on multistep methods. We synthesized a series of coordination polymers (1-4) with excellent fluorescence and catalytic activity. Moreover, 1 and 2 exhibit significantly higher fluorescence than other compounds, indicating that 1 and 2 could be efficient multifunctional fluorescence probes for high-sensitivity sensing of nitrobenzene, and 1 can be used as a highly sensitive fluorescent sensor to detect Tb3+, with a detection limitation of 5 × 10−7 M. In addition, the as-prepared Ag@compound 1 shows remarkable catalytic performance to reduce 4-NP, with a reduction rate constant k as large as 2.07 × 10−2 s−1. [ABSTRACT FROM AUTHOR]

As we know, two important factors should be considered for choosing the time step HT ht in the step-by-step integration algorithm. In order to approximate the simple harmonic wave through discrete data points, time step HT ht . In general, it is better when HT ht . This is a prerequisite for determining HT ht . [Extracted from the article]

Modernized trams usually run on exclusive rail lanes along urban streets, but they share the right of way with general vehicles at intersections and often get interrupted by traffic signals. We developed a mixed integer model to resynchronize traffic signal timings to favor tram movements. The objective is to balance the operational needs between minimizing bidirectional tram travel times and reducing the likelihood of activating the green extensions. The model depicts both tram and vehicle progressions in one signal timing plan, making it possible to control the impact of signal timing resynchronization through traffic. Trams following the tram bands produced by the proposed model are prevented from being stopped by red phases at signalized intersections. The applicability and effectiveness of the proposed model were demonstrated in a real-world case study. Compared with the state-of-the-art practice approach, the developed model reduced tram travel time by 10% with lower negative impacts on traffic on side streets. The reduction in tram travel time was obtained without sacrificing the mobility of through traffic. [ABSTRACT FROM AUTHOR]

DM is often accompanied by macrovascular complications. Obtusifolin, which is an anthraquinone-based compound with antioxidant activity, is obtained from the seeds of Cassia obtusifolia. In this study, the potential effect of obtusifolin was investigated in human umbilical vein endothelial cells. The results from flow cytometry analysis revealed that pretreatment with obtusifolin depressed the production of cellular reactive oxygen species that was induced by high glucose content. Moreover, the results showed that pretreatment with obtusifolin reduced the level of malondialdehyde, as well as recovered the activities of mitochondrial complex I/III, catalase and superoxide dismutase. Furthermore, flow cytometry analysis also revealed that mitochondrial membrane potential and cell apoptosis were recovered, and inhibited by obtusifolin, respectively. The expression of X chromosome-linked IAP was upregulated, whereas the expressions of poly ADP-ribose polymerase and cysteinyl aspartate specific proteinase-3/9 were downregulated by the pretreatment with obtusifolin. Notably, the western blot analyses showed that the release of Omi/HtrA2 into the cytosol was prevented by the pretreatment with obtusifolin. Conclusively, it was suggested that obtusifolin may provide protection against mitochondrial apoptosis largely through inhibition of the release of Omi/HtrA2 from mitochondria into cytosol. [ABSTRACT FROM AUTHOR]

In this paper, we perform the nonlinear frequency response function (FRF) estimation for a class of nonlinear systems. Two non-parametric estimation techniques are considered: radial basis function neural network (RBF-NN)-based estimation and support vector machine (SVM)-based estimation. Based on the system's available observations, the proposed estimation models are used to predict its frequency response. Simulation results are provided to demonstrate the model implementation. Finally, a comparative study is carried out to evaluate the effectiveness of the RBF-NN and SVM schemes, which has demonstrated that the SVM outperformed RBF-NN in the FRF estimation. [ABSTRACT FROM AUTHOR]

Development of nonprecious metal-based catalysts highly active for complete oxidation of CH 4 at a temperature ≤600 °C is significant for removing unburned CH 4 at exhaust of engines of vehicles using natural gas or liquefied petroleum gas. CeO 2 is active for complete oxidation of CH 4 . Co 3 O 4 has been identified as a promising catalyst for this reaction. A Co 3 O 4 /CeO 2 nanocomposite catalyst consisting of ceria nanorods supported on Co 3 O 4 nanoparticles was prepared through a modified deposition precipitation method. The Co 3 O 4 /CeO 2 nanocomposite exhibits high activity for complete oxidation of methane with an apparent activation energy of 43.9 kJ/mol, which is obviously lower than 95.1 kJ/mol of pure CeO 2 and 89.7 kJ/mol of pure Co 3 O 4 , suggesting a synergetic effect between Co 3 O 4 and CeO 2 . Surface of the Co 3 O 4 /CeO 2 nanocomposite during complete oxidation of CH 4 in the temperature range of 200–500 °C and potential stable intermediate of this catalysis were identified with ambient pressure X-ray photoelectron spectroscopy (AP-XPS). [ABSTRACT FROM AUTHOR]

• All 76 SCI articles concerning dynamic-mechanical behaviors of high-entropy alloys up to January 2023 are reviewed. • The experimental methods, theoretical models and dynamic-mechanical properties of 61 reported high-entropy alloys have been summarized. • The dynamic-deformation mechanisms of high-entropy alloys are analyzed and classified according to different microstructures. • The potential applications and prospects concerning the dynamic-mechanical behaviors of high-entropy alloys are prospected. High-entropy alloys (HEAs) are a family of novel multi-principal alloys containing >4 principal elements in equimolar ratios or nearly-equimolar ratios. The unique multiple-principal components bring in the high configurational entropy or mixing entropy, and some unique microstructures of HEAs. Consequently, many impressive properties of HEAs, including outstanding dynamical mechanical performance, have been reported successively. Under the instantaneous loading with high strain rates (ε ̇ >103 s−1), dynamic-deformation mechanisms of materials are different from the static one, and the relevant influencing factors are complicated. To reveal the relationship between the unique microstructures of HEAs and their dynamic-mechanical properties, 76 articles published during the period of July 2015 to January 2023 have been reviewed in the present work. Firstly, the statistics and classification of all 61 reported HEAs are systematically done in terms of their processing, experimental method, theoretical model, phases and microstructures as well as the dynamic-mechanical properties. Secondly, theoretical models and deformation mechanism are summarized. The effects of dislocation motion, twinning, and phase transformation behavior on dynamic deformation of HEAs are discussed thoroughly. The adiabatic-shear behavior and its effect on dynamic deformation are also considered. The differences of dynamic-mechanical behavior as well as the relevant mechanisms between HEAs and traditional metallic materials are described. Finally, the potential application under dynamic loads of HEAs are demonstrated thoroughly. The present article additionally deals with the future research directions of dynamic-mechanical behaviors in order to develop novel high-performance HEAs. [ABSTRACT FROM AUTHOR]

Formaldehyde (FA) has neurotoxic characteristics and causes neurodegenerative disease. Our previous study demonstrated the neuroprotective effects of hydrogen sulfide (H 2 S) on FA-induced neurotoxicity in HT22 cells. Emerging evidence have supported that ferroptosis is involved in FA-induced neurotoxicity. To understand the mechanism of the protection of H 2 S against FA-induced neurotoxicity, this study explored the regulatory effect of H 2 S on FA-induced ferroptosis and the underlying mechanisms. The researcher found that H 2 S (100, 200, and 400 μM, 30 min) reverses the ferroptosis induced by FA (100 μM, 24 h) in HT22 cells (a cell line of mouse hippocampal neurons), including decreases in free iron, reactive oxygen species (ROS), 4-hydroxy-2-trans-nominal (4-HNE), and malondialdehyde (MDA) contents, as well as an increase in glutathione (GSH) content. H 2 S (100, 200, and 400 μM, 30 min) also inhibited ferritinaphagy in FA-exposed HT22 cells, as evidenced by the downregulation of the ferritinophagy receptor nuclear receptor coactivator 4 (NCOA4) and microtubule-associated protein 1 light chain-3B (LC3B) as well as the upregulation of the main iron storage protein ferritin heavy chain 1 (FTH1) and p62. H 2 S (100, 200, and 400 μM, 30 min) also up-regulated the expression of growth differentiation factor-11 (GDF11) in FA-exposed HT22 cells. Furthermore, knockdown of GDF11 in HT22 cells cancelled the beneficial effects of H 2 S in FA-induced ferroptosis and ferritinaphagy. These data indicated that the protective mechanism underlying H 2 S-prevented neurotoxicity of FA is involved in alleviating FA-induced ferroptosis via inhibiting ferritinaphagy by upregulation of GDF11. [Display omitted] • Hydrogen sulfide upregulates GDF11 protein expression in formaldehyde-treated HT22 cells. • Hydrogen sulfide antagonizes formaldehyde-induced ferritinophagy and ferroptosis. • Silencing GDF11 reversed the protective effect of hydrogen sulfide on formaldehyde-induced ferritinophagy. • Silencing GDF11 reversed the protective effect of hydrogen sulfide on formaldehyde-induced ferroptosis. [ABSTRACT FROM AUTHOR]

In this study, the copper-mordenite zeolite (Cu-MOR) and non-thermal plasma were used to produce methanol and hydrogen from methane and water at low temperature (120 °C) without CO 2 formation. Energy efficiency for methanol and hydrogen were 68.8 mmol·kJ−1 and 562.3 mmol·kJ−1, respectively, and the selectivity of methanol in liquid products reached 86%. The reaction mechanism likely involves methane being excited to methyl (·CH 3) and hydrogen radicals (·H) under DBD plasma conditions, which can then adsorb on the catalyst surface at the Cu 2 -(μ-O)2+ active sites, accompanied by water co-adsorption to facilitate formation and desorption of methanol. XPS analysis showed that with the prolongation of reaction time, Cu 2 -(μ-O)2+ was reduced to Cu+ and Cu(II) hydroxide, and the catalyst had carbon deposition, resulting in the decrease of catalytic activity. It is also worth noting that in an oxygen atmosphere, Cu 2 -(μ-O)2+ regenerates rapidly and eliminates catalyst carbon deposits. Trace oxygen was introduced into the reactor, and the reaction was carried out for 30 h, and the catalytic activity did not decrease. [Display omitted] • Plasma-catalytic conversion of methane and water to methanol and hydrogen. • Using water as oxidant, methanol selectivity in the liquid phase reached 86%. • Plasma promoted adsorption of methyl radicals on Cu-MOR active site Cu 2 -(μ-O)2+. • The methane-water process route has no CO 2 emissions. [ABSTRACT FROM AUTHOR]

A new approach is developed for the reliable classification of Calculus bovis along with the identification of willfully contaminated C. bovis species and the quantification of unclaimed adulterants. Guided by a principal component analysis, NMR data mining achieved a near-holistic chemical characterization of three types of authenticated C. bovis , including natural C. bovis (NCB), in vitro cultured C. bovis (Ivt -CCB), and artificial C. bovis (ACB). In addition, species-specific markers used for quality evaluation and species classification were confirmed. That is, the content of taurine in NCB is near negligible, while choline and hyodeoxycholic acid are characteristic for identifying Ivt -CCB and ACB, respectively. Besides, the peak shapes and chemical shifts of H 2 -25 of glycocholic acid could assist in the recognition of the origins of C. bovis. Based on these discoveries, a set of commercial NCB samples, macroscopically identified as problematic species, was examined with deliberately added sugars and outliers discovered. Absolute quantification of the identified sugars was realized by qHNMR using a single, nonidentical internal calibrant (IC). This study represents the first systematic study of C. bovis metabolomics via an NMR-driven methodology, which advances the toolbox for quality control of TCM and provides a more definitive reference point for future chemical and biological studies of C. bovis as a valuable materia medica. [Display omitted] • This study represents the foray of NMR-involved systematic study of C. bovis. • PCA analysis of qHNMR data enabled preliminary classification of C. bovis. • Species-specific markers for the identification of C. bovis were determined. • Comprehensive metabolomic analysis for C. bovis through NMR was achieved. • Untargeted identification and content determination of adulterants were realized. [ABSTRACT FROM AUTHOR]

This paper presents a novel Lagrangian approach to attitude tracking for rigid bodies. The 4-DOF Lagrangian dynamics presented in this paper describes the rotational rigid motion on the unit sphere. Energy conservation property is explored, which holds on the entire unit quaternion group. This enables one to address the full attitude control problem where the attitude may evolve on the entire rotation group and to design controllers to track any desired attitude by leveraging the rich literature on energy-shaping based control methodology in Euclidean space. Global exponential tracking on the unit quaternion group is achieved using a simple potential function. In addition, the adaptive technique is used to deal with unknown on-orbit torque disturbances and uncertainties of the inertia matrix. Simulations are included to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

Thirteen undescribed dimeric Erythrina alkaloids, named as erythrivarines A1–A13, were isolated from the barks of Erythrina variegata L. and. Their structures were determined on the basis of NMR, UV and mass spectral analyses. Dimeric Erythrina alkaloid with a C-8/8′ linkage in erythrivarine A1 was not yet reported. Representative dimers from titled plant were used to prove their occurrence as natural products by LC − MS detection. Additionally, simultaneous investigation enabled us to propose the natural property of seemingly artificial Erythrina alkaloid with acetonyl group. Thirteen undescribed dimeric Erythrina alkaloids were isolated. Dimeric Erythrina alkaloid with a C-8/8′ linkage in erythrivarine A1 is not yet reported. Representative dimers from titled plant were proved their occurrence as natural products by LC-MS detection, which enabled us to propose the natural property of seemingly artificial products with acetonyl group. [Display omitted] [ABSTRACT FROM AUTHOR]

Precise indoor positioning is increasingly essential for Internet of Things (IoT) deployments. Within the IoT framework, many resource-limited devices require accurate positioning capabilities. Therefore, as a lightweight online learning algorithm, kernel adaptive filter (KAF) has been adopted for indoor positioning. However, the environments and mixed noise often lead to the inaccuracy of indoor positioning. In order to tackle this problem, this paper proposes a novel fractional-derivative kernel adaptive filtering method, which has two significant features: The fractional-derivative assisted weight-update strategy can accurately reflect data distributions and system characteristics, thereby improving the accuracy of prediction. Secondly, the Student's t -based kernel function can effectively combat non-Gaussian noise in indoor positioning applications, thus the prediction robustness can be well guaranteed. In three representative indoor positioning scenarios, the proposed algorithm is compared with state-of-the-art KAFs and widely used positioning methods (Trilateration, KNN, Naive Bayesian, and transfer learning). Experimental results show that the proposed method can improve positioning accuracy by at least 5.98% with the well-robustness property. • A new weight-update strategy for KAF is proposed based on the fractional derivative. • A new KAF based on the weight-update strategy is proposed and applied for indoor localization. • The proposed KAF has higher positioning accuracy. • The proposed KAF can maintain good robustness. [ABSTRACT FROM AUTHOR]

The coupling action of calcium leaching and chloride attack is an important durability problem for the cement-based materials served in long-termly in the environmental water like seawater or groundwater containing chloride. This paper investigates the influence of calcium leaching on the chloride diffusivity in cement-based materials by the corrosion experiment, in which the hardened cement paste (HCP) specimens are immersed into three corrosion solutions with the same chloride concentration, such as 1 M sodium chloride solution, 1 M ammonium chloride solution and the mixed solution of 1 M sodium chloride and 3 M ammonium nitrate. Some measurements, like the phenolphthalein, saturation-drying weighing, mercury intrusion porosimetry (MIP), Scanning Electron Microscopy (SEM/EDS), X-ray diffraction analysis (XRD) and rapid chloride test (RCT), are used to analyze the leaching behaviors and its influence on the chloride diffusivity of HCP, characterized by leaching depth, pore structure, morphology, calcium-silicon ratio, chloride-silicon ratio, phase composition and free chloride ion content. Results show that, in the calcium leaching process, the compactness, calcium hydroxide content and calcium-silicon ratio of C-S-H gel of HCP decreases with the leaching time. The calcium leaching causes the reduction of the physically chloride-bound ability and the chemically chloride-absorbed ability in HCP, and it results in high chloride diffusivity. [ABSTRACT FROM AUTHOR]

SnSe is a promising thermoelectric material with a record high dimensionless figure of merit ZT at high temperature ∼923 K. However, the ZT values for low-Temperature Pnma phase SnSe are just 0.1–0.9. Here, we use First-principle combine with Boltzmann transport theory methods to study the effect of tensile and compressible strain on the thermoelectric transport properties. The power factor of SnSe with −4% strain have a large boost along b and c directions of 7.7 and 3.9 μW cm −1  K −2 , respectively, which are 2.5 and 2 times as large as those pristine SnSe. The charge density distributions reveal that the overlap of wave function has significant change due to the changed bond lengths and bond angles under different strain, which lead to the change of band gap and band dispersion. Our work provides a new effective strategy to enhance the thermoelectric properties of materials. [ABSTRACT FROM AUTHOR]

Single crystalline tin selenide (SnSe) has attracted considerable attention due to its record high figure of merit value in medium temperature range. However, their large band gap restricts the electron transport. Herein, we tailor the carrier concentration by offering a variability of the Sn/Se ratio to fine-tune the electrical transport properties. Density functional theory demonstrated that the collaborative optimization of the Seebeck coefficient and the electrical conductivity through optimizing carrier concentration can improve significantly the power factor, and deviation from stoichiometry is an effective strategy to modulate the carrier concentration because anti-site defects Sn Se lower the Fermi level and increases the number of carrier pockets in SnSe. Meanwhile, experimental observations confirm that the carrier concentration and electrical conductivity are changed with varied Sn/Se ratio. Through this work, a viable design principle for optimized carrier concentration for achieving high thermoelectric performance is provided. [ABSTRACT FROM AUTHOR]

In this paper, the existence and multiplicity of positive solutions are obtained for a class of Kirchhoff type problems with two singular terms and sign‐changing potential by the Nehari method. [ABSTRACT FROM AUTHOR]

Transition metal elements are the most important elements of heterogeneous catalysts used for chemical and energy transformations. Many of these catalysts are active at a temperature higher than 400 °C. For a catalyst containing a 3d or 5d metal element with a low concentration, typically their released fluorescence upon the K-edge or L-edge adsorption of X-rays is collected for the analysis of chemical and coordination environments of these elements. However, it is challenging to perform in situ/operando X-ray absorption spectroscopy (XAS) studies of elements of low-energy absorption edges at a low concentration in a catalyst during catalysis at a temperature higher than about 450 °C. Here a unique reaction system consisting two reactors, called a dual reactor system, was designed for performing in situ or operando XAS studies of these elements of low-energy absorption edges in a catalyst at a low concentration during catalysis at a temperature higher than 450 °C in a fluorescent mode. This dual-reactor system contains a quartz reactor for preforming high-temperature catalysis up to 950 °C and a Kapton reactor remaining at a temperature up to 450 °C for collecting data in the same gas of catalysis. With this dual reactor, chemical and coordination environments of low-concentration metal elements with low-energy absorption edges such as the K-edge of 3d metals including Ti, V, Cr, Mn, Fe, Co, Ni, and Cu and L edge of 5d metals including W, Re, Os, Ir, Pt, and Au can be examined through first performing catalysis at a temperature higher than 450 °C in the quartz reactor and then immediately flipping the catalyst in the same gas flow to the Kapton reactor remained up to 450 °C to collect data. The capability of this dual reactor was demonstrated by tracking the Mn K-edge of the MnOx/Na2WO4 catalyst during activation in the temperature range of 300-900 °C and catalysis at 850 °C. [ABSTRACT FROM AUTHOR]

Abstract: The preoptic area (POA) of the hypothalamus, containing temperature‐sensitive and temperature‐insensitive neurons, plays a key role in specific thermoregulatory responses. Although arginine vasopressin (AVP) has been shown to induce hypothermia by increasing the firing activities of warm‐sensitive neurons and decreasing those of cold‐sensitive and temperature‐insensitive neurons, the effects of AVP on POA GABAergic transmission remain unknown. Herein, inhibitory postsynaptic currents (IPSCs) of temperature‐sensitive and temperature‐insensitive neurons in POA slices were recorded using whole‐cell patch clamp. By monitoring changes in GABAergic transmission during AVP treatment, we showed that AVP decreased the amplitudes and frequencies of spontaneous IPSCs in mostly warm‐sensitive neurons and in some temperature‐insensitive neurons but increased these parameters in other temperature‐insensitive neurons. The IPSC amplitude was reduced for only cold‐sensitive neurons. RT‐PCR and Western blot analyses further confirmed the POA expression of V1a receptors and GABAA receptors, including the subunits α1, α2, α3, β2, β3 and γ2. The effects of AVP on IPSCs in temperature‐sensitive and temperature‐insensitive neurons were dependent on G proteins and intracellular Ca2+. AVP‐mediated modulation was associated with changes in the kinetic parameters (decay time, 10–90% rise time, half‐width). Together, these results suggest that AVP, acting via V1a receptors but not V1b receptors, differentially modulates GABAergic synaptic transmission and fine‐tunes the firing activities of temperature‐sensitive and temperature‐insensitive neurons in the rat POA. [ABSTRACT FROM AUTHOR]

Pervaporation membranes made from polyethersulfone (PESU), polyphenylsulfone (PPSU), polytrimethylphenylethersulfone (T-PESU) and hydrophilic PESU-co-Pluronic (H-PESU) polymers were evaluated for dehydration of ethanol and methanol. Fundamental characteristics of pore structure, free volume, d-spacing, water contact angle, water and ethanol uptakes were investigated and correlated with their dehydration performance. The H-PESU membrane shows the best ethanol dehydration performance due to its synergetic combination of the strengths from both rigid hydrophobic PESU and flexible hydrophilic Pluronic moieties. It has the highest water permeability of 0.322 mg m −1  h −1  kPa −1 which is 2–6 times higher than other three membranes because the hydrophilic Pluronic moiety may form special water transport channels. It also has a comparable mole-based selectivity of 685 due to the rigid hydrophobic PESU moiety that prevents the membrane from uncontrolled swelling. Long-term tests evidence the operating stability of both H-PESU and PESU membranes. In addition, the methanol dehydration performance of these membranes is superior to the other reported polymeric membranes. The water in the permeate can be concentrated to 86.8%. These promising preliminary results suggest that these polyarylether (PAE) membranes have great potential for ethanol and methanol dehydration. [ABSTRACT FROM AUTHOR]

Two new copper–iodine cluster-based frameworks, namely, {Cu4I4[Cu(5-eatz)2]2}n (1; 5-eatzH = (1S)-1-(5-tetrazolyl)ethylamine) and {Cu4I4Cu(5-eatz)2}n (2), are synthesized. For comparison purposes, the compound {2[N(CH3)4]+·Cu12I12[CuI(5-eatz)2]2}n (3) reported by us is also included. These compounds have similar porphyrin-like Cu(5-eatz)2 units but different Cu–I sub-structures, for example, the discrete Cu4I4 unit in 1, the 1D Cu–I graphene-like nanoribbon in 2 and the 3D Cu–I framework in 3, which can be obtained under tunable synthesis conditions. These structure features lead to the deep color appearance of crystals and strong adsorption in the visible light region. The diffuse reflectance spectra show that compounds 1 and 2 exhibit very low Eg values, which are equal to 1.18 eV for 1 and 1.12 eV for 2. Interestingly, all of them exhibit excellent intrinsic photocatalytic activity to degrade methylene blue (MB) under visible light. 2 shows better photocatalytic performance than 1 and 3, and can almost completely degrade MB in 300 minutes (with a degradation amount of 90%) without any sacrificial agents. Meanwhile, their photocatalytic activities are in the order 3 ＜ 1 ＜ 2, which is opposite that of their Eg (3 ＞ 1 ＞ 2) values (Eg3 = 1.49 eV). Remarkably, all of 1, 2 and 3 can completely photodegrade the MB solution in 30 minutes in the presence of H2O2. The results demonstrate the potential application of copper–iodine cluster-based frameworks for the photocatalytic degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Background: Sintilimab combined with IBI305 treatment regimen had potential clinical benefits than sorafenib in the first‐line treatment of patients with unresectable hepatic cell carcinoma (HCC). However, whether sintilimab plus IBI305 has economic benefits in China remains unclear. Methods: From the perspective of Chinese payers, we used the Markov model to simulate patients with HCC receiving treatment with sintilimab plus IBI305 and sorafenib. The transition probability between health states was estimated using the parametric survival model, and the cumulative medical costs and utility of the two treatment methods were estimated. Considering the incremental cost‐effectiveness ratios (ICERs) as the evaluation index, sensitivity analyses were performed to explore the impact of uncertainty on the results. Results: Compared to sorafenib, sintilimab plus IBI305 generated an additional $17552.17 and 0.33 quality‐adjusted life years, resulting in an ICER of $52817.89. The analysis outcomes were most sensitive to the total cost of sintilimab plus IBI305. With a willingness‐to‐pay threshold of $38,334, sintilimab plus IBI305 showed a 1.28% probability of being cost‐effective. The total cost of sintilimab plus IBI305 should be reduced by at least 31.9% to be accepted by Chinese payers. Conclusions: Regardless of whether the price of sintilimab plus IBI305 and sorafenib is covered by Medicare, sintilimab plus IBI305 is unlikely to be cost‐effective for first‐line treatment of patients with unresectable HCC. [ABSTRACT FROM AUTHOR]

Frequency response functions (FRF) are often used in the vibration controller design problems of mechanical systems. Unlike linear systems, the FRF derivation for nonlinear systems is not trivial due to their complex behaviors. To address this issue, the convergence property of nonlinear systems can be studied using convergence analysis. For a class of time-invariant nonlinear systems termed as convergent systems, the nonlinear FRF can be obtained. The present paper proposes a nonlinear FRF based adaptive vibration controller design for a mechanical system with cubic damping nonlinearity and a satellite system. Here the controller gains are tuned such that a desired closed-loop frequency response for a band of harmonic excitations is achieved. Unlike the system with cubic damping, the satellite system is not convergent, therefore an additional controller is utilized to achieve the convergence property. Finally, numerical examples are provided to illustrate the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]

In this paper, forced vibration of functionally graded (FG) nanobeams resting on the nonlinear elastic foundations are investigated based on the nonlocal strain gradient theory. The material parameters of FG nanobeams are assumed to be temperature-dependent and change continuously along the thickness direction according to the power-law function (PFGM) or sigmoid function (SFGM). Based on the Euler–Bernoulli beam theory and von-Kármán geometric nonlinearity, the governing equations of motion are derived by considering the deviation between the geometrical and physical neutral surfaces. Closed-form approximate solution for nonlinear forced vibration of a FG nanobeam is derived by using multiple time scale method. The results show that decrease of non-homogeneity index and material length scale parameter, or increase of temperature variation and nonlocal parameter will increase the resonance frequencies of FG nanobeams. The effect of the in-coincidence of physical and geometrical neutral surfaces on the nonlinear resonance of the nanobeams could not be ignored, especially for SFGM nanobeams with larger non-homogeneity index and stronger size effects, embedded in a softer medium with obvious temperature variation. [ABSTRACT FROM AUTHOR]

A terbium organic framework (Tb-MOF), {[Tb2(Pyznpy)6·4H2O]·2H2O}n (1) (Hpyznpy = 4-((3-(pyrazin-2-yl)-1H-pyrazol-1-yl) methyl) benzoic acid), has been synthesized under solvothermal conditions. X-ray crystal analysis indicates that 1 crystallizes in the triclinic form with P-1 space group, and six petal-like 1D chains are connected by hydrogen bonds and π···π interactions to form the 3D structure of 1. Tb-MOF 1 exhibits an intense green fluorescence under UV light. The fluorescent nature of 1 suggests that Tb-MOF 1 could be an efficient multifunctional fluorescence probe for sensitivity sensing of small organic molecules and metal ions, especially for nitrobenzene and Fe3+. The mechanism of the sensing properties was studied as well. [ABSTRACT FROM AUTHOR]

Seven new compounds, [Zn(pypymba) 2 ] n ( 1 ), [Co(pypymba) 2 ] n ( 2) , [Cd(pypymba) 2 ] n ( 3 ), [Cd(Hpypymba)Cl 2 ] n ( 4 ), {[Cd(pypymba)Cl]·C 2 H 5 OH·H 2 O} n ( 5 ), [Cd(pypyaa)Cl] n ( 6 ), {[Cd 2 (pyznpy) 2 Cl 2 H 2 O]·H 2 O} n ( 7 ) [Hpypymba = 4-((3-(pyrazin-2-yl)-1H-pyrazol-1-yl)methyl)benzoic acid, Hpyznpy = 4-((3-(pyridin-2-yl)-1H-pyrazol-1-yl)methyl)benzoic acid, Hpypyaa = 2-(3-pyridin-2-yl)-1 H -pyrazol-1-yl)acetic acid], were hydrothermally synthesized by tuning the metal ion's species, counter anions, solvents and pH values and characterized by routine methods: XRD, elemental analysis, fluorescence properties analysis, TGA and crystal structure analysis and single-crystal X-ray crystallography. The main structures of the compounds 1 , 2 , and 3 are extended to similar 3D structures by C – H … N, C – H … O hydrogen bonds and π … π stacking under the same synthesis method. Each Cd(II) node of compound 4 has four chlorine bridges (two pairs of double chlorine); Each Cd(II) node of compounds 5, 6 has two chlorine bridges (a pair of double chlorine bridges), while their spatial structures are expanded in different ways. Compound 7 also contains chlorine atoms, but does not contain chlorine bridged structures. The luminescent properties of compound 7 and the ones immersed in various kinds of organic compounds and nitrate@EtOH solutions have been investigated. Importantly, 7 shows highly sensitive response to nitrobenzene and Fe 3+ through luminescence quenching effects, making it a promising luminescent sensor for nitrobenzene and Fe 3+ . [ABSTRACT FROM AUTHOR]