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Circular RNA (circRNA), an emerging non-coding RNA, is closely related to the processes of lipid deposition, inflammatory response, apoptosis, proliferation and repair in atherosclerosis (As), and affects the development of As. Traditional Chinese medicine (TCM) has an important academic value in the prevention and treatment of As, and its regulatory mechanism has not been comprehensively summarized. This paper reviewed the association of circRNA with lipid deposition, inflammatory response and macrophage in As, and summarized the research progress of the correlation between circRNA and atherosclerosis and the regulation of traditional Chinese medicine. [ABSTRACT FROM AUTHOR]

Modern high-end digital manufacturing has continuously improved the performance requirements for servo drive systems. High-performance servo drive systems should have excellent dynamic performance and steady-state performance. At present, an AC permanent magnet servo drive system using a permanent magnet synchronous motor as the drive motor has become the mainstream of contemporary servo drive systems. Servo system (servo mechanism), also known as servo systems, generally contains feedback control links, mainly used to accurately follow or reproduce a certain process. The servo system is mainly composed of a controller, a power drive device, a feedback device, a transmission device, a motor, and a load. In a servo system, the existence of mechanical resonance will cause serious damage to the transmission mechanism of the system and will reduce the reliability and accuracy of the system. When the performance of the system deteriorates severely, it will lead to system instability or even safety accidents. This article aims to study the use of fuzzy sliding mode control methods to control the generation of mechanical resonance, to further eliminate the phenomenon of mechanical resonance in the servo system. This paper puts forward the methods to eliminate chattering generated by sliding mode control, mainly including filtering method, eliminating uncertainty, intelligent algorithm optimization, reducing switching gain, and fan shape. The experimental results in this paper show that when the angular speed feedback of the motor is adopted, the maximum value of the speed difference is close to 3rad/s. It can be considered that there is resonance in the system, and the load resonance is the main factor. When the angular velocity feedback at the load end is used, the maximum value of the speed difference is about 0.05rad/s, and it can be considered that the resonance has been successfully suppressed. [ABSTRACT FROM AUTHOR]

Subacromial impingement syndrome (SIS) is defined as pressurization and impingement between the acromion, the bursa under the acromion, and the rotator cuff during the abduction and elevation of the shoulder joint, resulting in pain and a functional disturbance of elevation. It is the most common disorder of the shoulder, accounting for 44-65% of all complaints of shoulder pain during a physician's office visit. The study was performed with the aim of valuing the magnetic resonance imaging (MRI) and computed tomography (CT) in diagnosing patients with SIS. A total of 68 patients with SIS were selected as study subjects and subjected to MRI and CT examinations. The diagnostic accuracy and sensitivity of MRI and CT were, respectively, 97.06 and 70.59% (P < 0.05); the detection rates of SIS grade I, grade II, and grade III by MRI were 91.67%, 96.77%, and 100%, respectively, which were significantly higher than 50%, 80.65%, and 68% by CT, respectively (P < 0.05). MRI and CT detection indicated that there was no significant difference in extensive rotator cuff tear, acromion stenosis, and normal acromion detected by MRI and CT (P > 0.05). In conclusion, the diagnostic accuracy, sensitivity, and detection rate of acromion of MRI were higher compared with those of CT examination, and MRI is more suitable in the clinical diagnosis of SIS. [ABSTRACT FROM AUTHOR]

Abstract: Bacteria that form biofilms are often highly resistant to antibiotics and are capable of evading the host immune system. To evaluate the role of flagellin and F4 fimbriae on biofilm formation by enterotoxigenic Escherichia coli (ETEC), we deleted the fliC (encoding the major flagellin protein) and/or the faeG (encoding the major subunit of F4 fimbriae) genes from ETEC C83902. Biofilm formation was reduced in the fliC mutant but increased in the faeG mutant, as compared with the wild-type strain. The expression of AI-2 quorum sensing associated genes was regulated in the fliC and faeG mutants, consistent with the biofilm formation of these strains. But, deleting fliC and/or faeG also inhibited AI-2 quorum sensing activity. [Copyright &y& Elsevier]

Abstract: In 550°C and H2 current, the mesoporous nickel–silica composite core–shell microspheres with tunable chamber structures have been successfully prepared by reduction of Ni3Si2O5(OH)4 microspheres, which are synthesized by the reaction between Ni(Ac)2·4H2O and SiO2 microspheres via a self-template approach. The chamber (SiO2 core sizes) and shell thickness (40–150nm) of the nickel–silica microspheres can be controlled by adjusting the synthetic parameters of Ni3Si2O5(OH)4, such as the reaction time. After reduction, these microspheres still have the same sizes, morphologies, and core–shell structures with porous shell as before. These mesoporous nickel–silica microspheres with large BET surface area, exhibit good catalytic activity in m-dinitrobenzene (m-DNB) and high selectivity of m-phenylenediamine (m-PDA) after 3.5h, but different selectivity of m-PDA in the progress, showing good potential in the catalyst industry. [Copyright &y& Elsevier]

Abstract: Orthorhombic single-crystalline cerium carbonate hydroxide (CeCO3OH) with one-dimensional (1D) microstructures has been successfully synthesized by a facile sonochemical reaction between cerous nitrate and urea. These 1D microstructures were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM). The as-synthesized CeCO3OH has uniform lengths and good dispersion. Synthetic parameters, such as the concentration of reagents, were found to have close relationship with the morphologies and sizes of the final products. The ultrasound-induced oriented attachment growth mechanism has been proposed for the possible formation mechanism of sample. Room-temperature photoluminescence of CeCO3OH samples with different morphologies has also been investigated. [Copyright &y& Elsevier]

CeO2 hollow microspheres have been synthesized by hydrothermal decomposition reaction of Ce(NO3)3 on the surfaces of silica microspheres. The shell thickness of CeO2 hollow microspheres can be controlled from 20 to 50nm by adjusting the concentration of Ce(NO3)3 in the reaction solution. The high UV absorption of CeO2 hollow microspheres indicates that this material is suitable as a UV-blocking material. [Copyright &y& Elsevier]

Abstract: Orthorhombic single-crystal CeCO3OH flower-like nanostructures have been successfully synthesized on a large scale by the hydrothermal method at 120°C using Ce(NO3)3·6H2O as the cerium source, aqueous urea as both an alkaline and carbon source and polyvinyl alcohol as surfactant. Polycrystalline CeO2 nanostructures have been obtained by thermal decomposition–oxidation of single-crystalline CeCO3OH flower-like nanostructures at 500°C in flowing air. CeCO3OH flower-like nanostructures and CeO2 nanostructures were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), room temperature UV/vis absorption spectrum, differential scanning calorimetric analysis (DSC), and thermogravimetric analysis (TG). The high absorption in the UV region for CeO2 nanostructures indicated that this material was suitable as UV-blocking material. [Copyright &y& Elsevier]

Turning the harmful NO into value-added chemicals is a promising alternative to achieve the electrocatalytic NO upgrading and maintain the global N-balance. However, the reaction mechanisms and electrochemical performances and are still needed to be further investigated. Herein, the development of electrochemical NO reduction and oxidation reaction (NORR and NOOR) were respectively summarized. In the NORR part, we summarized the electrocatalytic reaction systems, including directly NORR (NO to NH 3 /NH 2 OH) and the C-N coupling reactions with CO x for urea, and organic molecules for amino acid, oxime. The reaction mechanisms and design principles of electrocatalysts for different reaction systems were reviewed, combining theoretical calculations and advanced characterization techniques. The NO reaction is also a potential approach to replace others cathodic reduction. Finally, the challenges and outlooks in this fields have been proposed. The electrocatalytic NO reaction not only realizes the efficient green utilization, but also provides guidance for nitrogen economy. [Display omitted] • Electrochemical NO reactions are reviewed from theory and experiments. • The NO reduction, oxidation, and C-N coupling reactions are introduced. • The design principle and reaction mechanism towards specific product are emphasized. • The relationships between e-structure, adsorption energy, and activity are studied. • The current challenges and future opportunities are summarized. [ABSTRACT FROM AUTHOR]

Electrocatalysts of NiCoFe hydroxides have been prepared successfully by a simple hydrothermal method, which show excellent electrocatalytic properties. (delivering 10 mA cm−2 current density at 230 mV, with a Tafel slope of 72.7 mV·dec−1). Furthermore, in order to further improve its electrocatalysis properties, the NiCoFe hydroxide is reprocessed by vulcanizing and acid etching, respectively. The electrocatalytic properties of the NiCoFe hydroxides after vulcanization is further improved (delivering 10 mA cm−2 current density at 200 mV, with a Tafel slope of 46.3 mV·dec−1). Similarly, acid etching is also a simple and effective method to promote the OER catalytic activity, which resulted in an exfoliation process and multiple defects. The NiCoFe LTHs is stripped into a thinner nanosheet structure, and the electrochemical analysis shows excellent electrocatalytic properties (delivering 10 mA cm−2 current density at 184 mV, with a Tafel slope of 37.8 mV·dec−1). Both vulcanization and acid etching show better oxygen evolution capability than the pristine LTHs in alkaline conditions with a small Tafel slope and good durability. This work will break a new and inexpensive path to promote the catalytic capability in an alkaline condition. • NiCoFe layered ternary hydroxides were synthesized using one-step hydrothermal method. • Vulcanization and acid etching promote catalytic properties of NiCoFe layered ternary hydroxides for oxygen evolution reaction. • The interface structure and multiple vacancies increased the catalytic active sites. • Electrocatalysts after vulcanization and acid etching exhibit better OER performance than bare NiCoFe layered ternary hydroxides. [ABSTRACT FROM AUTHOR]

Abstract: Bundle-like structures consisting of single crystal cerium hydroxide carbonate (Ce(OH)CO3) nanorods have been synthesized successfully by a hydrothermal method at 100 °C using cerium nitrate (Ce(NO3)3·6H2O) as the cerium source, aqueous carbamide both as an alkaline and carbon source and cetyltrimethylammonium bromide (CTAB) as surfactant. X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were used to characterize such bundle-like structures. SEM and TEM images show that Ce(OH)CO3 bundle-like structures were composed of nanorods with diameters of ∼100 nm. The XRD pattern and electron diffraction (ED) pattern indicate that Ce(OH)CO3 has a pure orthorhombic single crystal structure. [Copyright &y& Elsevier]

Abstract: Uniform and well-dispersed cadmium selenide (CdSe) nanorods, with lengths of ∼10μm, have been successfully synthesized via solvothermal routes using diethanolamine (DEA) as reagent to control morphology. Effect of other solvents on morphology of products, including ethanolamine (MEA) and triethanolamine (TBA), has been discussed. The nanostructures were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. [Copyright &y& Elsevier]

Abstract: SnO2 hollow microspheres have been synthesized by a hydrothermal method. X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM) were used to characterize such hollow microspheres. SEM image shows that SnO2 microspheres with diameters of 0.5–1 μm are composed of SnO2 nanoparticles with about 15 nm in diameter. Some broken microspheres indicate the hollow spherical structure. XRD shows that SnO2 hollow microspheres have tetragonal structure. [Copyright &y& Elsevier]

Transition metal sulfides have demonstrated excellent heavy metal detoxification in previous studies. However, the activity of their S-functional sites is usually not maximized because they are not precisely regulated. Herein, we report a new short-term cathodic tuned CuS crystals (C-tuned CuS) distortion strategy, ultrafast detoxicating over 95% Cr(VI) in 1 min，its detoxification rate was elevated by five orders of magnitude times compared to the untuned one. The high Cr(VI) detoxification performance is mainly attributed to the layered sulfur atoms tuning within series of cathodic potential shown by In-situ Raman. Besides, the four-tuning stages of C-tuned CuS lattice distortion based on the variation of Raman peak height and redshift changes was investigated by density functional theory (DFT) calculations, showing that the S-S bonds was stretched under cathodic tuning, extending from 2.106 to 2.345 Å. The stretched S-S bonds with enhanced polarity and electron activity prevailed the formation of transient Cr-S bonds with Cr(VI), favoring the direct electron transfer without O mediation, thus reducing the Cr(VI) reduction energy barrier. Cathodic tuning CuS crystal distortion, a "Plug and Play" strategy, show a new electron-level microscopic insights into wastewater reduction techniques development. [Display omitted] • Ultrashort-time cathodic electrical stimulation activates strong S-S activity in CuS. • The existence of four stages of S-S bond activation stretching is verified. • Two-electron-activated S-S bonds have strong reducing activity toward Cr(VI). • Activated S-S bonds don't need O as an intermediate for electron transfer thus reducing energy barriers. [ABSTRACT FROM AUTHOR]

Abstract: A 2-pyrazoline derivation of 1-phenyl-3-(4-methylphenyl)-5-(3,4-dimethyl phenyl)-2-pyrazoline has been characterized by X-ray single crystal diffraction, UV-vis and fluorescence spectroscopy. For the title compound, density functional theory (DFT) calculations of the structure and natural population atomic charge analysis have been performed at B3LYP/6-311G** level of theory. By using TD-DFT method, electron spectra of the title compound have been predicted, which suggest the B3LYP/6-311G** method can approximately simulate the electron spectra for the system presented here. Comparative studies on the title compound with 1-phenyl-3-(4-methylphenyl)-5-phenyl-2-pyrazoline indicate that introducing electron-donating groups in 5-phenyl ring of pyrazoline ring influences the peak location and intensity in electronic and fluorescence spectra. [Copyright &y& Elsevier]

Abstract: Octahedral Cu2O particles and Cu2O nanowires were synthesized by a simple solution-phase route using N2H4·H2O as reducing agent at room temperature. Amorphous carbon nanofibers were synthesized using octahedral Cu2O particles and an acetylene gas source at atmospheric pressure. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric (TG) analysis. SEM and TEM images indicated that most of the obtained octahedral Cu2O particles had an edge length of 400–700nm. The obtained nanowires had uniform diameters of about 15nm, and the length of the nanowires ranged from 5 to 10μm. The XRD result revealed the amorphous feature of the nanofibers. IR spectrum revealed that the nanofibers consist of –CH, –CH2, –C and –CH3 groups. The concentrations of N2H4·H2O and NaOH played important roles in controlling the geometric shape of the Cu2O. [Copyright &y& Elsevier]

Hydrogen production coupled with electrochemical refining of long-chain biomass saccharide for high-value d -glucaric acid (GRA) through preferential the 1,4-glycosidic bond cleavage followed by the aldehyde/hydroxyl groups oxidation. [Display omitted] • Biomass saccharide oxidation for glucaric acid coupled with hydrogen production was realized. • Preferential 1,4-glycosidic bond cleavage is followed by the –CHO/ –COOH oxidation. • The –CHO and –CH 2 OH oxidation in glucose/maltose via NiOOH is spontaneous. Chemicals electrochemical refining coupled with cathode hydrogen production could effectively reduce the overpotential and energy cost. The electrooxidation cleavage of 1,4-glycosidic bond is the urgent problems for high-value d -glucaric acid (GRA) directly from the long-chain biomass saccharide composed of glucose. Hence, we investigated the oxidation path of the maltose over the α-Ni(OH) 2 as model electrocatalyst. The results showed that the cleavage potential of maltose 1,4-glycosidic bond is a little higher than that of the aldehyde/hydroxyl groups in glucose, but much lower than that of water. Compared with water oxidation, the aldehyde/hydroxyl groups oxidation could consume the Ni(OH)O intermediate so fast that it cannot accumulate. Operando electrochemical impedance spectroscopy (EIS) showed that the 1,4-glycosidic bond cleavage is not same to the aldehyde/hydroxyl groups oxidation reactions spontaneously, which occurs directly at an initial potential. The morphology of α-Ni(OH) 2 would be collapsed and high-priced nickel and metal-oxygen bond would be formed during water oxidation reaction, but which unchanged for glucose and maltose oxidation. In addition, the starch was also used as the long-chain saccharide to study the 1,4-glycosidic bond cleavage and the whole reaction path. This work promotes the development of green electrocatalytic systems to achieve sustainable valorization of biomass saccharide utilization pathways. [ABSTRACT FROM AUTHOR]

The stability of non-noble metal catalysts for water oxidation is remaining a great challenge in acidic solution. Herein, alcohols oxidation instead of water oxidation coupled with ultradurable H 2 production was realized. The MnO 2 crystal phase regulation could optimize the electronic structure, and the δ-MnO 2 with more Mn3+ showed a higher activity, including a low overpotential of 1.48 V at 50 mA cm−2, and a small Tafel slope of 176.22 mV dec−1. Moreover, the δ-MnO 2 catalyst exhibited extremely high stability after 24 h for EG oxidation, while the activity was quickly lost within 0.5 h for water oxidation. This work indicated that crystal phase regulation could improve the active and stability of acidic water splitting catalysts. • Acidic OER replaced by alcohol oxidation greatly enhanced the catalysts stability. • The proportion of Mn3+ in δ-MnO 2 could efficiently improve the activity. • The -CH 2 OH oxidation inhibited the lattice oxygen mechanism. • The crystal phase regulation of MnO 2 could optimize the electronic structure. [ABSTRACT FROM AUTHOR]

MoS 2 @C hollow nanospheres are synthesized by in situ vapor phase sulfurization of the spherical polypyrrole-polyoxometalate (PPy-PMo 12 ) precursors, in which MoS 2 layers with widened interlayer spacing of 0.98 nm and amorphous carbon are generated. The vapor phase sulfurization process can retain the spherical morphology of the PPy-PMo 12 precursor, and facilitate the formation of the MoS 2 @C hollow structures. When used as anode materials for lithium-ion batteries, the MoS 2 @C hollow nanospheres exhibit excellent lithium storage performances compared to the bulk MoS 2 , including high specific capacity (1225.6 mAh g −1 at 0.1 A g −1 ), excellent rate capability (452 mAh g −1 at 8 A g −1 and 389.6 mAh g −1 at 10 A g −1 ), and good cycling stability (94.3% capacity retention after 500 cycles at 1 A g −1 ). The hollow structures of interlayer-expanded MoS 2 @C hollow nanospheres could provide more active sites and buffer the volume changes for the electrochemical reactions. Moreover, the interoverlapped architectures between MoS 2 layers and carbon can greatly improve the electronic conductivity and cycle stability, thus leading to enhanced lithium storage performances. [ABSTRACT FROM AUTHOR]

Carbon encapsulated nanosheet-assembled MoS 2 (C@MoS 2 ) nanospheres have been synthesized using poly(vinylpyrrolidone) (PVP) as surfactant and carbon source via hydrothermal approach in combination with high-temperature calcination process. PVP plays an important role in the formation of nanosheet-assembled MoS 2 nanospheres, which can be in-situ converted into amorphous carbon to encapsulate MoS 2 . When evaluated for electrochemical lithium storage properties, the C@MoS 2 nanospheres exhibit enhanced electrochemical energy storage performances compared to the bare MoS 2 nanosheets, including high specific capacity (1135.8 mAh g −1 at 0.1 A g −1 ), excellent rate capability (384.4 mAh g −1 at 8 A g −1 and 330.5 mAh g −1 at 10 A g −1 ), and good cycling stability (97.03% capacity retention after 100 cycles at 0.5 A g −1 ). The enhanced lithium storage performances of the C@MoS 2 nanospheres can be ascribed to the boosted electronic conductivity arising from PVP derived carbon, and the facilitated lithium ion transport due to the shorter diffusion length of MoS 2 nanosheet-assembled structures. [ABSTRACT FROM AUTHOR]

Octahedron ceria crystals were fabricated by one-step hydrothermal synthesis without using any hard-template, with Ce(NO3)3·6H2O being raw materials and polyvinylpyrrolidone (PVP) being surfactant. The content of ethanol plays an important role in the morphology evolution of as-obtained CeO2. At 200°C, with the addition of ethanol into the water and by adjusting the ratio between ethanol and water from 1:3 to 3:1, the morphology of the as-obtained CeO2changed from solid octahedron to hollow irregular particles. When the ratio between ethanol and water is 1:1, prolonging the reaction time from initial 6 h to 12 h and ultimate 48 h, the morphology of the as-obtained CeO2growing from solid quasi-octahedron to regular octahedron, and then to hollow irregular particles. The electrochemical behavior of carbon paste electrode (CPE) modified by graphene/CeO2/CHIT nanocomposite membrane in 2.0 × 10–5 mol/L methylene blue (MB) containing 0.02 mol/L NaCl, and glassy carbon electrode (GCE) modified by MWNTs/CeO2/CHIT nanocomposite membrane in 1.0 mmol/L K3Fe(CN)6/K4Fe(CN)6(1:1) containing 0.5 mol/L KCl as the supporting electrolyte were measured respectively. The electrochemical measurements were carried out by cyclic voltammetric (CV) and differential pulse voltammetry (DPV). The synergistic effects of as-synthesized micro/nano CeO2and new carbon materials (MWNTs, graphene) on enhancing electrochemical signal were demonstrated, and a bright prospect of micro/nano octahedron CeO2on electrochemical application can be seen from this paper. [ABSTRACT FROM PUBLISHER]

Abstract: Flagellar structures contribute to the virulence of multiple gastrointestinal pathogens either as the effectors of motility, as adhesins, or as a secretion apparatus for virulence factors. Escherichia coli F18ab variant strains are associated with edema disease (ED) in pig industries worldwide. These strains use flagella to increase the efficiency of epithelial cell invasion. In this study, we aimed to elucidate the mechanism by which flagella contribute to F18ab E. coli invasion. To explore the role of flagella in the invasion process, we performed invasion assays with either flagellated and motile, flagellated but non-motile, or non-flagellated non-motile bacteria. We observed that flagellated but non-motile bacteria invade piglet epithelial cells even more efficiently than the parent wild-type (WT) strain in vitro. By contrast, the non-flagellated bacteria have significantly reduced invasion as compared with the parent strain. These results demonstrate that flagella function mainly as adhesins to enhance the ability of F18ab E. coli to target piglet epithelial cells. [Copyright &y& Elsevier]

Abstract: A novel nanocomposite membrane, comprising of nanosized shuttle-shaped cerium oxide (CeO2), single-walled carbon nanotubes (SWNTs) and hydrophobic room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), was developed on the glassy carbon electrode (GCE) for electrochemical sensing of the immobilization and hybridization of DNA. The properties of the CeO2–SWNTs–BMIMPF6/GCE, the characteristics of the immobilization and hybridization of DNA were studied by cyclic voltammetry and electrochemical impedance spectroscopy (EIS) using [Fe(CN)6]3−/4− as the redox indicator. The synergistic effect of nano-CeO2, SWNTs and RTIL could dramatically enhance the sensitivity of DNA hybridization recognition. The electron transfer resistance (R et) of the electrode surface increased after the immobilization of probe ssDNA on the CeO2–SWNTs–BMIMPF6 membrane and rose further after the hybridization of the probe ssDNA with its complementary sequence. The remarkable difference between the R et value at the probe DNA-immobilized electrode and that at the hybridized electrode could be used for label-free EIS detection of the target DNA. The sequence-specific DNA of phosphoenolpyruvate carboxylase (PEPCase) gene from transgenically modified rape was detected by this DNA electrochemical biosensor. Under optimal conditions, the dynamic range for detecting the sequence-specific DNA of the PEPCase gene was from 1.0×10−12 mol/L to 1.0×10−7 mol/L, and the detection limit was 2.3×10−13 mol/L, suggesting that the CeO2–SWNTs–BMIMPF6 nanocomposite hold great promises for the applications in sensitive electrochemical biosensor. [Copyright &y& Elsevier]