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Molybdate-coordinated zeolitic imidazolate framework (ZIF-67/MoO 4 2−) holey nanorods transformed from CoMoO 4 are rationally designed as a pyrolysis precursor to prepare the cobalt/ β -Mo 2 C nanoparticles uniformly decorated nitrogen-doped carbon (N-C/Co/Mo 2 C) holey nanorods. This strategy enables the resultant material to attain a high compositional uniformity, exhibiting excellent electrocatalytic activities for HER in 1.0 mol L−1 KOH aqueous solution. The hydrogen evolution reaction (HER) as a fundamental process in electrocatalysis plays a significant role in clean energy technologies. For an energy-efficient HER, it demands an effective, durable, and low-cost catalyst to trigger proton reduction with minimal overpotential and fast kinetics. Here, we successfully fabricate a highly efficient HER catalyst of N-C/Co/Mo 2 C holey nanorods with Co/ β -Mo 2 C nanoparticles uniformly embedded in nitrogen-doped carbon (N-C/Co/Mo 2 C) by pyrolyzing the molybdate-coordinated zeolitic imidazolate framework (ZIF-67/MoO 4 2−) holey nanorods, which result from the reaction between CoMoO 4 and MeIM in a methanol/water/triethylamine mixed solution. The uniform distribution of MoO 4 2− in the ZIF-67/MoO 4 2− enables Co/ β- Mo 2 C nanoparticles to be well-distributed within nitrogen-doped carbon holey nanorods. This synthetic strategy endows the N-C/Co/Mo 2 C catalyst with uniformly decorated bimetal, thus attaining excellent HER electrocatalytic activities with a small overpotential of 142.0 mV at 10 mA cm−2 and superior stability in 1.0 mol L−1 KOH aqueous solution. [ABSTRACT FROM AUTHOR]

The development of high-performance electrochemical energy storage devices is critical for addressing energy crises and environmental pollution. Hence, the design and preparation of next-generation electrode materials have been gaining increasing attention. Recent progress has demonstrated that three-dimensional (3D) carbon nanomaterials are extremely promising candidates for the electrodes of electrochemical energy storage devices due to their unique structural advantages of interlinked architecture. Herein, recent advances in the scalable fabrication of 3D carbon nanofiber (CNF)-based materials and their applications for electrochemical energy storage devices are summarized. Some representational 3D CNF architectures, such as CNF gels, 3D CNF films, 3D CNF arrays, and their nanocomposites, are highlighted with regard to various applications, including supercapacitors, lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), lithium-sulfur (Li-S), lithium-selenium (Li-Se), and metal-O2 batteries, as well as other new battery systems. Finally, contemporary challenges in the scalable fabrication of 3D CNF architectures are outlined and a brief outlook to future studies is given. This review illustrates significant opportunities for the macroscopic fabrication of 3D CNF architectures, and therefore inspires new discoveries to promote the practical applications of 3D CNF architectures in electrochemical energy storage fields. [ABSTRACT FROM AUTHOR]

The 3-hydroxypiperidine moiety is a privileged scaffold encountered in many bioactive compounds. An NADPH-dependent reductase (YGL039W) from Kluyveromyces marxianus ATCC 748 was isolated to show excellent catalytic activity in ( R )- N -Boc-3-hydroxypiperidine [( R )-NBHP] production. Using a GDH-catalyzed cofactor-recycling system to ensure a sufficient supply of NADPH, the effects of temperature, pH, metal ions, substrate concentration, biocatalyst dosage, and cofactors on the YGL039W-catalyzed bioreduction were investigated and optimized. Finally, an extremely high concentration of N -Boc-piperidin-3-one (NBPO, 400 g/L) could be completely reduced to ( R )-NBHP (> 99% ee ), with a total turnover number of 20,000. This process shows significant potential for the industrial production of ( R )-NBHP. [ABSTRACT FROM AUTHOR]

Asymmetric reduction of ethyl 4-chloro-3-oxobutyrate (COBE) by carbonyl reductases presents an efficient way to produce Ethyl ( S )-4-chloro-3-hydroxybutanoate (( S )-CHBE), an important chiral intermediate for the synthesis of hydroxymethylglutaryl-CoA reductase inhibitors such as Lipitor ® . In this study, an NADPH-dependent carbonyl reductase (SrCR) from Synechocystis sp. was characterized to demonstrate a broad substrate spectrum, and the highest activity (53.1 U/mg protein) with COBE. To regenerate the cofactor NADPH, Bacillus subtilis glucose dehydrogenase was successfully coexpressed with SrCR. Owing to the product inhibition, no more than 400 mM of COBE could be completely reduced to ( S )-CHBE using the recombinant Escherichia coli/ pET-SrCR-GDH. The macroporous adsorption resin HZ 814 was applied to adsorb ( S )-CHBE in situ to alleviate the product inhibitio. Consequently, 3000 mM (494 g/L) of COBE was bioconverted within 8 h, resulting in a ( S )-CHBE yield of 98.2%, with 99.4% ee and total turnover number of 15,000, revealed great industrial potential of ( S )-CHBE production. [ABSTRACT FROM AUTHOR]

( S )- N -Boc-3-hydroxypiperidine (( S )-NBHP) is an important chiral intermediate for the synthesis of ibrutinib, an anticancer drug targeting B-cell malignancies. An NADPH-dependent reductase (YDR541C) from Saccharomyces cerevisiae was isolated and found to show excellent catalytic activity in the production of ( S )-NBHP. The reductase YDR541C was cloned and overexpressed in Escherichia coli BL21 (DE3), purified to homogeneity, and its catalytic properties were studied. Furthermore, an ethyl caprylate-water (1:1, v/v) biphasic system was introduced to alleviate product inhibition. After optimization of the reaction, as much as 1200 mM N -Boc-piperidin-3-one (NBPO) (240 g/L) was asymmetrically reduced to ( S )-NBHP within 6 h, resulting in a yield of 99%, an enantioselectivity of >99.5% ee , and a total turnover number (TTN) of 8000. These results indicate great potential for industrial application. [ABSTRACT FROM AUTHOR]

Recently, heteroatom-doped three-dimensional (3D) nanostructured carbon materials have attracted immense interest because of their great potential in various applications. Hence, it is highly desirable to exploit a simple, renewable, scalable, multifunctional, and general strategy to engineer 3D heteroatom-doped carbon nanomaterials. Herein, a simple, eco-friendly, general, and effective way to fabricate 3D heteroatom-doped carbon nanofiber networks on a large scale is reported. Using this method, 3D P-doped, N,P-co-doped, and B,P-co-doped carbon nanofiber networks are successfully fabricated by the pyrolysis of bacterial cellulose immersed in H3PO4, NH4H2PO4, and H3BO3/H3PO4 aqueous solution, respectively. Moreover, the as-prepared N,P-co-doped carbon nanofibers exhibit good supercapacitive performance. [ABSTRACT FROM AUTHOR]

Vanadium‐based intercalation materials have attracted considerable attention for aqueous zinc‐ion batteries (ZIBs). However, the sluggish interlaminar diffusion of zinc ions due to the strong electrostatic interaction, severely restricts their practical application. Herein, oxygen vacancy‐enriched V2O5 structures (Zn0.125V2O5·0.95H2O nanoflowers, Ov‐ZVO) with expanded interlamellar space and excellent structural stability are prepared for superior ZIBs. In situ electron paramagnetic resonance (EPR) and X‐ray diffraction (XRD) characterization revealed that numerous oxygen vacancies are generated at a relatively low reaction temperature because of partially escaped lattice water. In situ spectroscopy and density functional theory (DFT) calculations unraveled that the existence of oxygen vacancies lowered Zn2+ diffusion barriers in Ov‐ZVO and weakened the interaction between Zn and O atoms, thus contributing to excellent electrochemical performance. The Zn||Ov‐ZVO battery displayed a remarkable capacity of 402 mAh g−1 at 0.1 A g−1 and impressive energy output of 193 Wh kg−1 at 2673 W kg−1. As a proof of concept, the Zn||Ov‐ZVO pouch cell can reach a high capacity of 350 mAh g−1 at 0.5 A g−1, demonstrating its enormous potential for practical application. This study provides fundamental insights into formation of oxygen‐vacant nanostructures and generated oxygen vacancies improving electrochemical performance, directing new pathways toward defect‐functionalized advanced materials. [ABSTRACT FROM AUTHOR]

Lophatherum gracile , an important medicinal plant, is used traditionally in the treatment of cough associated with lung heat and inflammation. In this study, an ethanol extract of L. gracile (DZY) was shown to inhibit respiratory syncytial virus (RSV) infection and RSV-induced inflammation in vitro and in vivo. These findings provide a strong and powerful support for the traditional use of L. gracile in the treatment of RSV-related diseases. To determine the anti-RSV activities of DZY and its ingredients, and explore the relationship between RSV infection and inflammation. DZY was extracted from L. gracile and its major ingredients were determined by high-performance liquid chromatography (HPLC). RSV-infected HEp-2 and RAW264.7 cell models were established to assess the inhibitory effect of DZY on RSV replication and nitric oxide (NO) production in vitro. Three-week-old BALB/c mice challenged intranasally with RSV were used to establish RSV-infected animal mode. The mice were respectively administered DZY at high-, middle-, and low-dose in different groups. The anti-RSV activity of DZY was evaluated by detecting viral load, lung lesion, CD4+ and CD8+ T cell population, and interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ expression in the lung tissue. In HEp-2 cell line, DZY effectively inhibited RSV infection in a dose-dependent manner with IC 50 values of 20 μg/mL against RSV (Long strain) and IC 50 values of 25 μg/mL against RSV (A2 strain). The anti-RSV activity of DZY was mainly determined by isoorientin, swertiajaponin, 3, 5-di-caffeoylquinic acid, and 3, 4-di-caffeoylquinic acid. Moreover, DZY suppressed NO production induced by RSV in vitro. In vivo , oral administration of DZY significantly reduced the viral load and ameliorated lesions in the lung tissue. A probable antiviral mechanism was mediated by slightly improving the ratio of CD4+/CD8+ T cells and inhibiting the mRNA and protein expression of IL-1β, TNF-α, and IFN-γ. (1) DZY exhibits anti-RSV activities both in vitro and in vivo. (2) RSV infection can trigger a series of inflammatory reactions; thus, ameliorating inflammation is helpful to control the course of disease caused by RSV. These findings provide the rationale and scientific evidence behind the extensive use of L. gracile in traditional medicine for the treatment of diseases potentially caused by RSV. fx1 [ABSTRACT FROM AUTHOR]

A new aromatic glycoside (1) and a new natural product, neolignan (2), along with twenty-three known compounds (3-25), were isolated from the thorns of Gleditsia sinensis. According to the spectroscopic analyses (IR, UV, HRESIMS, NMR and ECD), the structures of isolates were elucidated. Herein, compounds 4, 6-8, 10-13, 15, 16, 18, 20, 23 were isolated from the plant of G. sinensis for the first time. Moreover, compounds 4, 6, 15 and 24 showed cytotoxic effects on human ovarian cancer (SKOV-3) cells with IC50 values of 24.83 ± 4.90, 48.86 ± 9.11, 80.13 ± 5.62, 15.38 ± 2.21 μM, respectively. [ABSTRACT FROM AUTHOR]

Background: Glomus tumor is a rare benign neoplasm, which most frequently occurs in the subungual regions of digits. Tumor rupture and infection occurred in one patient with a glomus tumor have never been reported.Case Presentation: We report a 59-year-old female presented to our hospital with a five-year history of progressively sharp pain and severe tenderness in the tip of her right middle finger. The treatment was surgical excision through a lateral incision accompanied with removal of the nail. After the surgery, the patient gained a functional recovery of her previously afflicted finger.Conclusions: To the best of our knowledge, this is the first case of finger infection caused by a ruptured subungual glomus tumor. Patients and physicians should be aware of the properties of glomus tumor so that early diagnosis and treatment of subungual glomus tumor as well as avoidance of tumor rupture and infection can be achieved. [ABSTRACT FROM AUTHOR]

Nine new labdane diterpenoids ( 1 – 9 ) were isolated from the aerial parts of Croton laui , along with eight known analogues ( 10 – 17 ). Their structures were identified on the basis of the spectral data (IR, UV, HRESIMS, 1D and 2D NMR), and the structure of 8 was confirmed by single crystal X-ray diffraction analyses. In addition, compounds 1 , 4 , 7 , 8 , and 14 showed weak anti-inflammatory activities in LPS-stimulated RAW 264.7 cells. [ABSTRACT FROM AUTHOR]

The aqueous rechargeable sodium‐ion battery (ARSIB) is considered to be the most promising candidate for large‐scale energy storage applications, due to its low cost, safety, and eco‐friendliness. However, the poor cycle life and low energy density of ARSIB impede its practical applications. In this context, hollow NaTi2(PO4)3 nanocubes anode is engineered through a facile, low‐cost, and large‐scale hydrothermal approach. Na0.44MnO2 cathode delivers a high capacity of 75.16 mAh g−1 with the compensation of sodium ions by the zinc metal‐induced pre‐sodiation of the anode in a deep eutectic electrolyte. The well‐designed structure in hollow carbon‐coated NaTi2(PO4)3 nanocubes enables high stability and rate performance. Moreover, the adoption of deep eutectic electrolytes can minimize the Mn dissolution in the Na0.44MnO2 cathode. When coupling the cathode and anode, the as‐assembled ARSIB with a deep eutectic electrolyte exhibits an ultralong cycle life up to 3500 cycles (with capacity retention of 90%), an ultrahigh energy density of 50.0 Wh kg−1, and superior rate capability (maximum power density of 1500 W kg−1). This ARSIB represents an alternative promising candidate for large‐scale electrochemical energy storage. [ABSTRACT FROM AUTHOR]

• A facile tip-shielding strategy was proposed via surface reduction process. • Selective adsorption procedure was achieved in interfacial modification. • The symmetrical cell exhibited enhanced cycling ability at high current density. Long-term reversibility and stability of aqueous Zn-ion batteries (AZIBs) at high current density are significantly impeded by uncontrolled Zn dendrites and side reactions on Zn anodes. Herein, a facile tip-shielding strategy was proposed via surface reduction approach aimed at liberating pure Zn sites for interfacial grafting of 5-amino-2-fluoro-pyridine (AFPD) molecular solid-electrolyte interface (SEI), realizing the direct utilization of the selective adsorption procedure in electrolyte optimization to substitute of the non-discriminatory modification process in interfacial engineering. This approach could effectively suppress Zn dendrite growth, hydrogen evolution reaction, and corrosion/passivation. Characterization and simulation results demonstrated that the parallel absorption mode of 5-amino-2-fluoro-pyridine (AFPD), preferential absorption of AFPD on non-Zn(0 0 2) facets, and homogeneous electric field distribution synergistically promote the deposition of planar and low-angle Zn lamellas. Consequently, the symmetrical battery assembled by the optimized AFPD-2–4@Zn electrodes achieved a significantly enhanced cycling performance (over 3400 h) in contrast to the bare Zn||bare Zn battery (approximately 370 h) at 5 mA cm−2 and 1 mAh cm−2. AFPD-2–4@Zn||MnO 2 full cell also manifested elevated capacity retention of approximately 70.2 % at 1 A/g after 700 cycles. This strategy introduces a facile tip-shielding strategy to construct robust Zn anodes for achieving the practical implementation of AZIBs, especially at high current densities. [ABSTRACT FROM AUTHOR]

Abstract: As a youthful family of crystalline porous materials, metal–organic frameworks (MOFs), assembled by inorganic vertices (metal ions or clusters) and organic ligands, feature ultrahigh porosity, high surface area, and synthetic and structural tailorability, along with relatively easy synthesis, making them excellent candidates for a large number of applications. Recently, increasing research interest in the electrochemical fields with regard to the environment and energy has been received. Lots of MOFs have been designed, prepared, and used in electrochemical applications, exhibiting fascinating performances. Here, the rational fabrication of electrochemical‐application‐directed functional MOFs and MOF composites is appraised. The synthetic strategies for the enhancement of corresponding MOF electrochemical behaviors are summarized and the relationship between structure and electrochemical performance is discussed. It is expected that the summary will be helpful for the future development of related MOFs and MOF composites with an excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Nine new title products are isolated, namely compound (I-IV) and diastereomers thereof, some of which show interesting anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 /carbon nitride (TCN-x) heterojunction photocatalyst was fabricated through the pyrolysis of an NH 2 -MIL-125/melamine mixture. • TCN-0.2 exhibited excellent photocatalytic activity towards tetracycline and methylene blue. • The as-prepared TCN-0.2 as a heterojunction photocatalyst largely improved the separation and migration of photoinduced electron-hole pairs. In this study, a highly efficient TiO 2 /carbon nitride (TCN-x) heterojunction photocatalyst was fabricated through the pyrolysis of an NH 2 -MIL-125/melamine mixture. The band edge positions of TiO 2 and carbon nitride (CN) matched well, leading to improved photogenerated electron-hole separation ability and consequently, improved photocatalytic performance of the TiO 2 /g-C 3 N 4 nanocomposite. This heterojunction photocatalyst exhibits excellent photocatalytic performance under visible light and effectively removes various water-soluble organic pollutants. Especially, the TCN-0.2 hybrid photocatalyst showed excellent photocatalytic activity and photocatalyst stability. With TCN-0.2, the maximum photodegradation efficiency of tetracycline (TC) and methylene blue (MB) are as high as 86.59% (60 min) and 91.40% (120 min), respectively. Compared with pristine TiO 2 and carbon nitride, the efficiency of TCN-0.2 for photocatalytic degradation of TC and MB is greatly improved. Photocurrent and electrochemical impedance spectroscopy further demonstrate that the TCN-0.2 hybrid composite accelerates charge transfer. [ABSTRACT FROM AUTHOR]

• This review focuses on the design of MOFs-based photocatalytic for H 2 production. • Revealing the preparation strategies for UV/Vis/NIR-photoactive MOFs-based catalysts. • Understand the relationship between MOFs-based catalysts performance and synthesis. Metal-organic framework (MOF) materials are suitable for photocatalytic hydrogen production reactions due to their tunable structure, modifiable pores and a large number of active sites. Recently, many studies have enhanced the light absorption capacity of MOF and promoted the separation of photogenerated charges by altering the structure of MOF materials or preparing MOF composites/derived materials. Besides, their hydrogen production efficiency and mechanism were analyzed in details. This review summarizes the photocatalytic hydrogen production applications of MOF-based materials based on lights with different wavelengths. [ABSTRACT FROM AUTHOR]

A new catalyst for the oxygen reduction reaction in fuel cells and metal-air batteries is prepared from aqueous solutions of carbonaceous nanofibers, pyrrole, and FeCl3 (room temperature, 4 h, followed by pyrolysis under flowing N2). [ABSTRACT FROM AUTHOR]