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This study provides a 16.2-kyr record of mercury (Hg) deposition derived from a lacustrine sedimentary sequence in Dahu Swamp, eastern Nanling Mountains. Results indicate that changes in climatic conditions had a significant effect on Hg concentrations (Hg–C) and accumulation rates (Hg-AR). Multi-proxy records including dry density, grain size, geochemical elements, organic matter and pollen indicators were compared with Hg accumulation. The results revealed that the contributions of detrital input and atmospheric deposition were minor, and Hg accumulation in the sediments was closely related to changes in climatic conditions: relatively drier and colder climate would result in shrinkage of the lake water body thus favoring increased formation of organic-rich peat or gyttja and leading to enhanced absorption of Hg by organic matter and result in increases of Hg–C and Hg-AR in sediments, and vice versa. Our results indicate that variations of Hg accumulation in Dahu Swamp were greatly impacted by climate under the influences of solar insolation changes and shrinkage or expansion of ice sheets in high latitudes to the north. The results of this study provide an insight into the response of Hg accumulation to low latitude climate processes in the East Asian summer monsoon region.

A monodisperse CeO2@N-C ultrathin nanosheet self-assembled hierarchical structure (USHR) has been prepared by metal-organic framework template methods. The uniform coating of nitrogen-doped carbon (N-C) layers could play an important role in the adsorption and activation of benzylic alcohol. The unique 3D hierarchical structure self-assembled by ultrathin nanosheets provided enough active sites for the catalytic reaction. Therefore, the CeO2@N-C USHR can afford excellent catalytic performance for selective oxidation of benzylic alcohols in water.

The development of multikilogram scale green and economical synthetic route of enantiomerically pure cis-4-amino-3-fluoro-1-methylpiperidine 1 is described. The synthesis features a highly regio-, ...

Improving the separation efficiency of photogenerated carriers and exposing more active sites are two important factors to improve the photocatalytic efficiency of photocatalysts. Designing appropriate materials with special structure and composition to achieve the above-mentioned objectives is the focus and hotspot of scientists' research. In this study, N-doped graphitic-carbon (NGC) cuboctahedral cage-supported core–shell Cu@In2O3 nanocomposites (denoted as Cu/In2O3@N–C) was prepared via the calcination of In-loaded HKUST-1 cuboctahedral nanoparticles. Using air(O2) as an oxidant, initiated by visible-light under ambient conditions, eco-friendly Cu/In2O3@N–C shows high efficiency, good recyclability, and excellent functional-group tolerability on the photocatalyzing home-coupling of terminal alkynes. Its highly enhanced photocatalytic performances are ascribed to its unique structural features. Precisely integrating the photoredox function of semiconductive In2O3, conductivity of Cu and NGC promotes rich generation and effective transfer-separation of photo-induced carriers. Intrinsically, the photocatalytic activity of Cu on the home-coupling of terminal alkynes and enhanced adsorptivity of phenylacetylene by the Cu/In2O3 heterostructure, which has been proved by DFT calculations, further boost photocatalytic efficiency. Simultaneously, hollow cuboctahedral cages provide abundant photoactive sites.

Nonmetallic doped metal oxides can be broad in their visible-light-response range. However, the half-filled or isolated impurity state can also be the new recombination center for photogenerated electrons/holes, which seriously influence the photocatalytic activity of the catalyst in the visible-light region. Therefore, how to prolong the photogenerated carrier life of nonmetallic doping metal oxides is the difficult and challenging topic in the field of photocatalysis. In this work, the hexagonal nanosheets assembled by N-doped C (N-C)-coated N-doped In2O3 (N-In2O3) nanoparticles (N-C/N-In2O3 HS) was obtained by simply pyrolyzing the In(2,5-PDC) hexagonal sheets. The N-C/N-In2O3 HS catalyst exhibit good photocatalytic activity and cycle stability in the long-wavelength region of visible light (λ = 520 and 595 nm). The effective utilization of long-wavelength visible light for N-C/N-In2O3 HS was mainly attributed to the acceptor-donor-acceptor compensation mechanism between the oxygen vacancy (VO) and substitutional N-doping (Ns) sites, which made the N-C/N-In2O3 HS possess a continuous band structure, without the half-filled or isolated impurity state in the band gap, and extended its light absorption edge to 733 nm. The compensation mechanism of nitrogen doping on In2O3 can promote the photocatalytic activity under longer-wavelength yellow light (595 nm) irradiation. The N-C layer coated on the N-In2O3 nanoparticles acted as a good acceptor of photogenerated electrons, facilitating the effective spatial separation of photogenerated carriers and extend photogenerated carrier lifetimes. The comparative photocatalytic experiments (N-In2O3 HS and N-C/N-In2O3 HS) show that the presence of N-doped C layer can enhance the photocatalytic efficiency by nearly 10-fold. This double-doping and carbon-coating strategy provided a novel research idea to solve the problem that nonmetal atoms doped metal oxides led to the secondary combination of photogenerated electrons/holes.

The low utilization efficiency in the visible region of the sunlight spectrum and the rapid recombination of photogenerated charge carriers are two crucial drawbacks that suppress the practical usage of metal oxide semiconductors as photocatalysts. In this article, we report a rational design of In2O3-In2S3 heterojunctions encapsulated by N-doped carbon with a hollow dodecahedral structure (In2O3-In2S3/N-C HDS), which can effectively handle the two drawbacks of metal oxide semiconductors and behave active for organic transformation under the irradiation of visible light even with long wavelengths. As exemplified by the selective oxidative coupling reaction of amine to imine, the obtained In2O3-In2S3/N-C HDS as the photocatalyst has exhibited excellent activity and stability. Experimental and density functional theory studies have verified that the excellent performance of In2O3-In2S3/N-C HDS can be attributed to the synergistic effect of In2O3-In2S3 heterojunctions, the coating of N-doped carbon, and the hollow porous structure with nanosheets as subunits.

Nuclear compartments have diverse roles in regulating gene expression, yet the molecular forces and components that drive compartment formation remain largely unclear1. The long non-coding RNA Xist establishes an intra-chromosomal compartment by localizing at a high concentration in a territory spatially close to its transcription locus2 and binding diverse proteins3-5 to achieve X-chromosome inactivation (XCI)6,7. The XCI process therefore serves as a paradigm for understanding how RNA-mediated recruitment of various proteins induces a functional compartment. The properties of the inactive X (Xi)-compartment are known to change over time, because after initial Xist spreading and transcriptional shutoff a state is reached in which gene silencing remains stable even if Xist is turned off8. Here we show that the Xist RNA-binding proteins PTBP19, MATR310, TDP-4311 and CELF112 assemble on the multivalent E-repeat element of Xist7 and, via self-aggregation and heterotypic protein-protein interactions, form a condensate1 in the Xi. This condensate is required for gene silencing and for the anchoring of Xist to the Xi territory, and can be sustained in the absence of Xist. Notably, these E-repeat-binding proteins become essential coincident with transition to the Xist-independent XCI phase8, indicating that the condensate seeded by the E-repeat underlies the developmental switch from Xist-dependence to Xist-independence. Taken together, our data show that Xist forms the Xi compartment by seeding a heteromeric condensate that consists of ubiquitous RNA-binding proteins, revealing an unanticipated mechanism for heritable gene silencing.

Background. The relationship of uric acid (UA) with the thyroid function among healthy individuals remains unclear. We aimed to examine the relationship between UA contents and thyroid hormone levels in healthy Chinese individuals. Methods. This was a cross-sectional study of 1186 Chinese adults (736 men and 450 women) who underwent a health check-up at the Huadong Hospital Affiliated to Fudan University (Shanghai, China) between January 1, 2010 and July 31, 2018. Clinical and thyroid hormone levels were compared in different UA groups (in male and menopause women groups, MG1: UA < 5 mg/dL; MG2: 5 mg/dL ≤ UA< 7 mg/dL; and MG3: UA ≥ 7 mg/dL; in female groups, FG1 to FG3 represent the UA levels of

Developing high-efficiency and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is crucial for various energy conversion systems. Herein, N/S co-doped C encapsulated hollow N...

This contribution reports an unprecedentedly efficient dimerization and the first successful polymerization of lignocellulose-based β-angelica lactone (β-AL) by utilizing a selective Lewis pair (LP) catalytic system, thereby establishing a versatile bio-refinery platform wherein two products, including a dimer for high-quality gasoline-like biofuel (C8 -C9 branched alkanes, yield=87 %) and a heat- and solvent-resistant acrylic bioplastic (Mn up to 26.0 kg mol-1 ), can be synthesized from one feedstock by one catalytic system. The underlying reason for exquisite selectivity of the LP catalytic system toward dimerization and polymerization was explored mechanistically.

Engineering p-n heterojunctions among metal oxide semiconductors to provide a built-in electric field is an efficient strategy to facilitate the separation of photogenerated electrons and holes and improve their photocatalytic activities. However, the inherent poor conductivity of p-n heterojunctions still limits the charge-transfer step and thus hampers their practical application in photocatalysis. In this work, a nitrogen-doped carbon-coated NiO/TiO2 p-n (NCNT) heterojunction with hierarchical mesoporous sphere morphology was synthesized by in situ pyrolytic decomposition of nickel-titanium complexes. The NiO/TiO2 p-n heterojunction in NCNT was fully characterized by several techniques, supported by theoretical calculations and Mott-Schottky plots. On coating with a thin nitrogen-doped carbon layer, the electron transfer of the obtained p-n heterojunction could be significantly enhanced. On account of the favorable structural features of the p-n heterojunction with nitrogen-doped carbon coating and hierarchical mesoporous structure, NCNT exhibited excellent photocatalytic activity toward various reaction systems, including the hydrogen evolution reaction and the visible-light-induced hydroxylation of phenylboronic acids.

N- and S-doped C-encapsulated CeO2 with a hinge-like nanostructure (CeO2@N,S-C HN) has been obtained by using a Ce-based metal-organic framework (Ce-MOF-808) as a precursor. Due to the synergistic effects of its special structure and N,S-doped C layer, CeO2@N,S-C HN exhibits high activity of photocatalytic hydrogen (H2) evolution. Density functional calculations are used to obtain a fundamental understanding of the high H2 production rate of CeO2@N,S-C HN.

Phosgene, a widely used but highly toxic substance, may pose a serious risk to public safety and health because of the potential abuse and possible accidental leakage. Consequently, it is of great significance to develop a rapid, reliable, and sensitive detection method for this noxious agent. In this work, an aggregation-induced emission-based sensor, 3,6-bis(1,2,2-triphenylvinyl)benzene-1,2-diamine (DATPE), has been rationally designed for detecting phosgene by conjugation of o-phenylenediamine (OPD) core as the reactive recognition moiety decorated with two peripheral triphenylethylene (TPE) units. A light-up fluorescence response is achieved by the fast cyclization reaction of OPD part and phosgene along with the formation of 2-imidazolidinone ring, thus inhibiting the intramolecular charge transfer quenching process in the sensor. Moreover, an easy-to-use test paper with DATPE is fabricated for onsite visual detection of phosgene in the gas phase even at a concentration of as low as 0.1 ppm.

Background and purpose Nonalcoholic steatohepatitis (NASH) is the more severe form of metabolic associated fatty liver disease (MAFLD), and no pharmacologic treatment approved as yet. Identification of novel therapeutic targets and their agents are critical to overcome the current inadequacy of drug treatment for NASH. Experimental approach The correlation between heat shock factor 1 (HSF1) levels and the development of NASH and the target genes of HSF1 in hepatocyte were revealed by chromatin-immunoprecipitation sequencing. The effects and mechanisms of SYSU-3d in alleviating NASH were examined in relevant cell models and mouse models (the Ob/Ob mice, high-fat and high-cholesterol diet, the methionine-choline deficient diet fed mice). The drug-like properties of SYSU-3d in vivo were evaluated. Key results HSF1 is progressively reduced with mitochondrial dysfunction in NASH pathogenesis and activation of this transcription factor by its newly-identified activator SYSU-3d efficiently ameliorated all manifestations of NASH in mice. When activated, the phosphorylated HSF1 (Ser326) translocated to nucleus and bound to the promoter of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) to induce mitochondrial biogenesis, thus increasing mitochondrial adaptive oxidation and inhibiting oxidative stress. The deletion of HSF1 and PGC-1α or recovery of HSF1 in HSF1-deficiency cells revealed the HSF1/PGC-1α metabolic axis mainly responsible for the anti-NASH effects of SYSU-3d independent of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK). Conclusion and implications Activation of HSF1 is a practicable therapeutic approach for NASH treatment via the HSF1/PGC-1α/mitochondrial axis, and SYSU-3d would take into consideration as a potential candidate for the treatment of NASH.

Porous organic polymers (POPs), owing to their abundant porosity, high stability and well-tunable properties, are promising candidates as heterogeneous photocatalysts for organic transformations. Here we report two vinylene-bridged donor–acceptor (D–A) structural POPs (TpTc-POP and TbTc-POP) that are facilely constructed by the electron-rich triarylamine and electron-deficient tricyanomesitylene as key building blocks by the organic base catalyzed Knoevenagel condensation. Both TpTc-POP and TbTc-POP possess hierarchical meso- and micro-pores with a high surface area. Furthermore, the unsubstituted vinylene linkages of D–A moieties in their polymer backbones extend their π-conjugation and render their broad absorption range in the visible-light region. Thus, these DA-POPs exhibited highly effective photocatalytic activities for aerobic oxidative coupling of amines to imines under visible light irradiation. This study shows the great potential of conjugated POPs with a D–A structural feature in designing highly efficient and active heterogeneous photocatalytic systems.

Intriguing porous architectures, fascinating physical and chemical properties, and wide application potentials have made metal–organic frameworks (MOFs) a class of highly promising functional materials. The inherent feature of incorporating decorative organic components as building blocks has facilitated MOF constructions by ingenious pre-design and post-synthetic modifications of the organic moieties through appropriate reactions. Meanwhile, the click chemistry has become an effective and robust tool in the fabrication and modification of various functional materials. The azide-alkyne 1,3-dipolar cycloaddition is usually conducted in mild conditions using diversely available substrates to generate 1,4-regioisomers of 1,2,3-triazoles as sole products in high yields, which meets the characteristics of the conceptual click chemistry and has been referred as the premier example of a click reaction. In 2007, the azide-alkyne 1,3-dipolar cycloaddition as a representative reaction of the click chemistry was introduced into the field of MOFs. In the past decade, utilizing the azide-alkyne 1,3-dipolar cycloaddition, not only lots of organic ligands have been designed and synthesized for MOF constructions, but also diverse functional groups have been grafted into/onto MOF networks for targeted applications. Although other click reactions, such as Diels-Alder click reaction and thiol-ene click reaction, have also been introduced into the MOF field, more and more successful examples have undoubtedly demonstrated that the azide-alkyne 1,3-dipolar cycloaddition is a highly efficient click reaction in the MOF construction and modification toward purposed applications. Herein, we highlight representative research progresses on MOFs derived from the azide-alkyne 1,3-dipolar cycloaddition along with their attractive applications. Accepted version

It is desirable but challenging to design efficient micro-/nanoreactors for chemical reactions. In this study, we have fabricated mesoporous double-shelled hollow microreactors composed of N-doped-C-coated ultrafine In2 O3 nanoparticles [N-C/In2 O3 HD (hollow dodecahedron)] by the thermolysis of a dodecahedral In-based framework in Ar atmosphere. The obtained N-C/In2 O3 HD exhibited excellent activity in the photocatalytic oxidative hydroxylation of a series of arylboronic acid substrates. This property can be attributed to its enhanced optical absorption and efficient separation of photo-generated electron-hole pairs, imparted by the unique structure and uniformly coated N-doped C layers. Furthermore, we found O2.- to be the critical active species in the process of photocatalytic oxidative hydroxylation of arylboronic acids, and the formation mechanism of this radical is also proposed. Theoretical calculations further confirmed that the N-doped C layer serves as an electron acceptor and revealed the microscopic charge-carrier migration path through the In2 O3 /N-doped graphite interfaces. Thus, photo-generated electrons from hybrid states of In2 O3 , composed of In 5s and 2p orbitals, are transferred into the hybrid states of N-doped graphite, composed of C 2p and N 2p orbitals. The present study may be helpful for understanding and designing carbon-based micro-/nanoreactors for photocatalytic reactions, and may also be useful for investigating related micro-/nanoreactors.

A typical catalytic process generally consists of diffusion, adsorption and surface reaction, which should be fully taken into account for the catalyst design. In this article, we synthesized hollow spheres (N,S-C/In2O3 HSs) assembled from N,S-codoped carbon layer coated In2O3 nanoparticles, in which the porous architecture could provide diffusion channels for reactant molecules, the N,S-codoped carbon layer could enhance the separation efficiency of photogenerated carriers, and the hollow structure could improve the amount of active sites and enhance the light utilization efficiency. The obtained N,S-C/In2O3 HS exhibits extraordinary photocatalytic oxidative hydroxylation of arylboronic acids under blue-light irradiation. From the theoretical calculations, it was found that the carbon layer not only strengthens the adsorption of arylboronic acid reactants, but also activates the boron atom in arylboronic acids. The present work indicates that the carbon layer could be used as a medium between inorganic semiconductor photocatalysts and organic reactant molecules, thus promoting the application scope of inorganic semiconductor photocatalysts in the field of selective organic synthesis.

Developing efficient and robust bifunctional electrocatalysts are in high demand for the production of hydrogen by water splitting. Engineering an electrocatalyst with a regulated electronic structure and abundant active sites is an effective way to enhance the electrocatalytic activity. Herein, N-doped C-encapsulated Ni nanoparticles (Ni@N-C) are synthesized through a traditional hydrothermal reaction, followed by pyrolyzing under an Ar/H2 atmosphere. The electrochemical measurements and density functional theory (DFT) calculations reveal that the electron transfer between the Ni core and the N-C shell induces the electron density redistribution on Ni@N-C, which directly promotes the adsorption and desorption of H* on the N-doped carbon (N-C) layer and thus dramatically enhances hydrogen production. Taking advantage of the porous spherical structure and the synergistic effects between Ni and N-doped carbon (N-C) layer, we obtain a Ni@N-C electrocatalyst that exhibits remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity with low overpotentials of 117 and 325 mV, respectively. Impressively, the assembled cell using Ni@N-C as both anode and cathode exhibits excellent activity as well as stable cyclability for over 12 h.

Catalysts based on metallic NPs have shown high activities in heterogeneous catalysis, due to their high fractions of surface-active atoms, which, however, will lead to the sacrifices in stability and recycle of catalysts. In order to balance well the relationship between activity, stability, and recovery, in this paper, we have constructed a 3D mesoporous sphere structure assembled by N-doped carbon coated Ni/Pd NP heterojunctions (Ni/Pd@N-C). This obtained Ni/Pd@N-C has shown high catalytic activity, durability and recyclability for the hydrolytic dehydrogenation of ammonia borane (AB). Further investigations, including experimental and theoretical results, have shown that the unique structural features, the synergistic effect between Ni and Pd, and the coating of N-doped carbon layer are responsible for the good catalytic performance of Ni/Pd@N-C mesoporous spheres.

Objective: Huqizhengxiao (HQZX) decoction is a mixture of traditional Chinese medicines comprising 10 herbs, with inhibitory effects on hepatocarcinoma. The aim of the study is to observe the antitumor efficacy and mechanism of HQZX decoction in nude mice with hepatocellular carcinoma xenografts. Methods: HepG2-luc subcutaneous hepatocarcinoma was established in nude mice. The mice were divided into 5 groups: control, cinobufagin, HQZXS, HQZXM, and HQZXH with doses 13.52, 27.03, and 54.06 g/kg, respectively. HQZX decoction was prepared for intraperitoneal intragastric administration for 3 weeks. Tumor growth was measured with Vernier calipers and in vivo imaging system. α-Fetoprotein (AFP) was determined by radioimmunoassay. Tumor necrosis factor–α (TNF-α) was measured with enzyme-linked immunosorbent assay (ELISA) assay. Telomerase activity was measured with polymerase chain reaction–ELISA. Nuclear mitosis and necrosis were observed with hematoxylin-eosin stain. Apoptotic proteins of caspase-3, Bcl-2, and Bax were examined by Western blot. Signaling molecules of ERK, mTOR, and STAT3 were measured with Luminex assay. Results: HQZX decoction showed good inhibition of HepG2-luc xenografts. Compared with control group, the relative tumor proliferation rate was less than 60% in the HQZXH and HQZXS. The tumor inhibition rate of HQZXH group reached 52% ± 15%. Relative average optical density values of the HQZXS and HQZXH groups decreased significantly. The mitotic index in HQZXS, HQZXM, and HQZXH groups decreased greatly. Telomerase activity of HQZXS was clearly reduced, and, the caspase-3 expression upregulated in HQZXH group. Bcl-2 expression was downregulated in HQZXS and HQZXH. The ratios of p-ERK/ERK and p-STAT3/STAT3 in HQZXS group were significantly downregulated. Conclusion: HQZX decoction can clearly inhibit the growth of hepatocellular carcinoma and induce tumor apoptosis. Its antitumor mechanism may be related to reducing telomerase activity and regulating the STAT3 and ERK signal pathway.

A new family of dihydrobenzoazaphosphosphole ligands was prepared and shown to enable modification of the phosphine electronic character by variation of the N-substituent. This new family of phosphines was shown to be highly active in the Pd-catalyzed Suzuki–Miyaura cross-coupling reaction with hindered coupling partners.

A photoactive triazolobenzothiadiazole (TBTD)-conjugated terphenyldicarboxylate (TPDC) linker was introduced into a porous and robust UiO-68 isoreticular zirconium metal-organic framework (denoted as UiO-68-TBTD) by the de novo synthetic approach of mixed TPDC struts. Under blue-light-emitting-diode irradiation, UiO-68-TBTD can serve as a heterogeneous photocatalyst for the highly efficient and selective oxidation of a sulfur mustard simulant (2-chloroethyl ethyl sulfide) to the corresponding much less toxic sulfoxide product, with a half-life of only 3 min in the open air atmosphere.

The high activity of exposed facets and large surface area have significant effects on the performance of photocatalysts because most of the photoreactivity properties of materials are related to surface processes. The strategy of combining high-index facets and a hollow structure into one material will provide a new way for designing effective photocatalysts, possessing active exposed facets and a large surface area at the same time. However, fabricating one material with both high-index facets and a hollow structure is still a great challenge due to their thermodynamic instability. Here, hollow anatase TiO2 octahedrons exposed with high-index (102) facets (HTO-102) were successfully fabricated for the first time by a facile hydrothermal method using HF and H2O2 as morphology controlling agents. Compared with two other catalysts (a solid sharp octahedron with (101) facets (SSO-101) and a hollow sharp octahedron with (101) facets (HSO-101)), HTO-102 particles exhibit a better photochemical activity for the selective aerobic oxidation of organic sulfides under visible-light irradiation. Experimental results and theoretical calculations indicate that the excellent photocatalytic activity of HTO-102 particles is mainly due to the synergistic effects of its hollow structure and exposed high-index (102) facets.

A new class of tunable heterophosphole dimeric ligands have been designed and synthesized. These ligands have enabled the first examples of Cu-catalyzed hydrogenation of 2-substituted-1-tetralones and related heteroaryl ketones via dynamic kinetic resolution, simultaneously creating two contiguous stereogenic centers with up to >99 : 1 dr and 98 : 2 er. The ligand-Cu complexes were isolated and characterized by single crystal X-ray, and DFT calculations revealed a novel heteroligated dimeric copper hydride transition state.

It is desirable but challenging to design noble-metal-free photocatalysts with improved activity for hydrogen (H2) evolution. In this study, we fabricated hollow hexagonal porous micro-rods assembled from core–shell In2O3@carbon nanoparticles (PHIC) via one-step thermal decomposition of the In-MIL-68 precursor. Under simulated sun-light illumination, the final H2 yield rate of PHIC is comparable to that of Pt/PHI (PHI, hollow hexagonal micro-rods assembled from In2O3 nanoparticles without a carbon layer), indicating that the continuous carbon layer coating on In2O3 nanoparticles has a Pt-like effect on improving the photocatalytic activity. Our experimental results indicated that the improved photocatalytic H2 evolution of PHIC is attributed to the synergistic effect of efficient separation of photo-generated electron–hole pairs caused by the coating carbon layer, the enhanced optical absorption of the hollow structure, and the improved accessibility provided by the porous structure. Among them, efficient separation of photo-generated electron–hole pairs plays the main role. Furthermore, we reveal the microscopic charge carrier migration path via In2O3/graphite interfaces, meaning that the photo-generated electrons from In2O3 O2p orbitals transfer into the carbon C2p orbitals, leaving the photo-generated holes in In2O3 O2p orbitals, which is beneficial to improve the separation of photo-generated electron–hole pairs.

The post-spreading seamount chain formed along the fossil ridge of the South China Sea (SCS) consists of carbonated silicate melts and alkaline basalts. These temporally and spatially linked samples give an intriguing case where CO2-rich magmas and associated basaltic rocks occurred upon the ultra-thin oceanic lithosphere, and thus they could carry robust information on the generation of alkaline magma via melting of carbonated mantle source. Here we present magnesium isotopic data (δ26Mg), and elemental and radiogenic isotope data for the lavas from the on-axis SCS seamount chain. Both the early- and late-stage samples classified based on their formation ages exhibit remarkable δ26Mg variations (−0.53‰ to −0.11‰ and − 0.38‰ to −0.23‰, respectively). The low-δ26Mg signatures found in two groups of the SCS samples indicate a recycled origin for the source carbon inventory. However, the low-δ26Mg endmember of the early-stage samples is characterized by low SiO2 and enrichment in rare earth elements (REEs), whereas the late-stage samples display a low-δ26Mg endmember that produced high-SiO2 and REE-depleted melts. The Mg-Nd isotope systematics suggest that the early-stage lavas were yielded by CO2-enhanced melting of sediment-rich oceanic crust (eNd = 4.2), whereas the late-stage lavas have sourced the residual and carbon-deficient oceanic crust (eNd = 8.7). Our model demonstrates that the melting of carbonated component can produce compositionally distinct carbonatitic and silicate melts in sequence due to different solidus temperatures. Owe to the relatively thin lithosphere, these two types of melt could individually appear along the fossil ridge of the SCS.

The present study employs microwave (MW) energy to enhance the co-pyrolysis of polyethylene terephthalate (PET) wastes and biomass. Based on the characterization of raw materials as well as gas and liquid products, we propose a pyrolysis mechanism of PET and biomass during microwave-assisted pyrolysis (MAP). The MAP of PET-biomass blends shows a synergetic effect that the interaction between PET and biomass promotes the yields of value-added products (e.g. aromatic acids and phenols) and suppresses the generation of biphenyls and polycyclic aromatic hydrocarbons, compared to the MAP of individual biomass or plastics. Besides, the blending ratio of PET-biomass has significant effect on the formation of major liquid products. The liquid product from the MAP of PET-biomass 4:1 blends contains above 30 wt.% chain hydrocarbon that can be used as gasoline and kerosene. Moreover, we evaluate the roles of three typical MW absorbing materials during MAP, including carbon powder, ferroferric oxide (Fe3O4) and calcium oxide (CaO). Carbon powder can enlarge the yield of main products from plastics pyrolysis due to its significant dielectric loss. Apart from the MW-absorbing ability, Fe3O4 can accelerate the esterification and decarboxylation reaction; CaO can convert acids into ketones and hydrocarbons through neutralization and catalytic cracking reactions.

Nephelinites, a highly alkaline volcanic rock type, have widely been thought to be formed in a shallow lithosphere previously impregnated with phlogopite and/or amphibole. Here we argue that nephelinites start melting at much greater depths than previously thought. Taking four Cenozoic nephelinitic volcanoes in eastern China as specific examples, we show that nephelinites have exceptionally low K/U and Ba/Th ratios, similar to most nephelinites worldwide, but their Nd-Sr-Hf isotopic compositions are inconsistent with a local lithospheric origin. They also have low, marine‑carbonate-like δ26Mg. We explain these features by partial melting of recycled, carbonate-bearing sediments in the mantle transition zone (MTZ; 410–660 km), where the high-pressure mineral liebermannite (KAlSi3O8, previously known as K-hollandite) is stable as a residual phase, preferentially retaining K, Ba, Rb and Pb relative to Th, U and light REE, thus releasing liquids with the characteristic trace-element patterns. Group-I kimberlites and oceanic HIMU basalts globally share the same peculiar geochemical anomalies characterizing the nephelinites, suggesting they may all have their roots in the MTZ. The nephelinites show correlations for Mg-Sr isotopes, 143Nd/144Nd-MgO, and δ26Mg-Ba/Th ratios, suggesting binary mixing between melts. We therefore invoke a two-stage process to generate these nephelinites. In the first stage, an initial carbonated silicate melt is formed by melting of carbonate-bearing sediments in the MTZ. Subsequently, during the ascent, the initial melt reacts with the surrounding peridotite, thereby generating a reacted melt, which ultimately mixes with the initial, unreacted carbonated silicate melt. Accordingly, Cenozoic nephelinites in eastern China can be regarded as evolved melts from the MTZ.

An efficient and practical synthesis of enantiomerically pure P-chiral dihydrobenzooxaphosphole (BOP) core 1 is developed that is amenable to large scale preparation of the related ligand series. The unique epimerization of the P-chiral center of the undesired (R,R)-diastereomeric phosphine oxide 19 through chlorination followed by crystallization makes this chemical resolution method achieve 65% yield of desired (R,S)-diastereomer 12.

Vinyl ester-unsaturated polyester resin (VER) with adipic acid presented the lowest shrinkage and highest flexural strength among VER with CaCO3, polymer vinyl acetate (PVAc), or adipic acid after curing. The Gibbs free energy change of adipic acid/VER specimen was the highest among pure VER, CaCO3/VER, PVAc/VER, and adipic acid/VER, indicating the lowest polymerization spontaneity of adipic acid/VER. Semiquantitative Fourier transform infrared proved that adipic acid did not consume during the curing process. With the presence of adipic acid, traditional two-step curing process of VER glue changed to a one-step curing process with a slower reaction rate constant via the analysis of the curing kinetics. 1H nuclear magnetic resonance and dynamic differential scanning calorimetry (DSC) show the existence of hydrogen bonding between VER and adipic acid. The network structure formed by hydrogen bonding of VER and adipic acid inhibited the cross-linking between unsaturated polyester and styrene, leading to the decrease of curing degree of adipic acid/VER. Thermogravimetric was applied to demonstrate the thermal decomposition behavior of adipic acid for VER, identifying the inefficient curing of adipic acid/VER characterized by DSC.

Ethnopharmacological relevance The Qingchangligan formula, a traditional Chinese medicine comprising five herbs, is useful for treatment of patients with liver failure; however, its protective and regulatory mechanisms remain elusive. Aim of the study To test the hypothesis that the Qingchangligan formula protects mice against acute liver failure by inhibiting liver inflammation. Materials and methods Acute liver failure (ALF) was induced by intraperitoneal injection of D -GalN (700 mg/kg) plus LPS (10 μg/kg). The Qingchangligan formula was administered to mice in three doses of 50 mg/kg (on day 1, day 2, and day 3) prior to D -GalN/LPS injection by intragastric administration. The mice in different groups were sacrificed at 6 h after D -GalN/LPS injection, and liver samples and blood were collected for analysis. Results Administration of the Qingchangligan formula not only ameliorated liver injury, as evidenced by reduced transaminase levels and well-preserved liver architecture, but also decreased the lethality in ALF mice. Moreover, in the ALF model, pretreatment with the Qingchangligan formula alleviated liver inflammation and decreased hepatocyte apoptosis. Further demonstrating the protective effects of the Qingchangligan formula, we found that pretreatment with the Qingchangligan formula reduced the expression of inflammatory cytokines by decreasing the expression of components of the mitogen-activated protein kinase (MAPK) pathway and promoting autophagy in vitro and in vivo . Conclusions Our findings demonstrated that the Qingchangligan formula exerts a protective effect against the pathophysiology of ALF, especially in regulating liver inflammation, and provide a rationale for using the Qingchangligan formula as a potential therapeutic strategy to ameliorate ALF.

Oxalyl chloride and phosgene are highly toxic chemicals but are widely used in industrial processes, which have been regarded as a serious threat to our health and public security. Thus, it is imperative to develop a convenient and reliable detection method for these noxious agents. In this research, we report the rational design of a fluorescent sensor (denoted as BTA) for simultaneously detecting oxalyl chloride and phosgene, in which o-phenylenediamine (OPD) as the reactive recognition site and benzothiadiazole (BTD) as the fluorophore moiety are coupled into one single benzo-fused motif. The probe works in a “turn-on” fluorescence mode due to the formation of piperazine-2,3-dione and 2-imidazolidinone rings by intramolecular cyclization reactions between the OPD part with oxalyl chloride and phosgene, respectively, which greatly inhibits the intramolecular charge transfer (ICT) process from two amines to the BTD core in the sensor BTA. The detection limit of oxalyl chloride and phosgene is as low as 3 nM and 20 nM in solutions, respectively. Moreover, the sensor exhibits outstanding selectivity toward oxalyl chloride and phosgene over the nerve-agent mimic diethyl chlorophosphate and various acyl chlorides. Furthermore, a portable test paper with BTA has been facilely fabricated for visual on-site detection of the two toxic chemicals in the gas phase.

One of the mechanisms in hyperuricemia (HUA)-induced renal tubular injury is the impairment of Na+-K+-ATPase (NKA) signaling, which further triggers inflammation, autophagy, and mitochondrial dysfunction and leads to cell injury. Here, we used RNA sequencing to screen the most likely regulators of NKA signaling and found that the liver kinase B1(LKB1)/adenosine monophosphate (AMP)-activated protein kinase (AMPK)/ mammalian target of rapamycin (mTOR) pathway was the most abundantly enriched pathway in HUA. AMPK is a key regulator of cell energy metabolism; hence, we examined the effect of AMPK on HUA-induced dysregulation of NKA signaling and cell injury. We first detected AMPK activation in high uric acid (UA)-stimulated proximal tubular epithelial cells (PTECs). We further found that sustained treatment with the AMPK activator 5-aminoimidazole-4-carboxamide 1-β-d-ribofuranoside (AICAR), but not the AMPK inhibitor Compound C, significantly alleviated UA-induced reductions in NKA activity and NKA α1 subunit expression on the cell membrane by reducing NKA degradation in lysosomes; sustained AICAR treatment also significantly alleviated activation of the NKA downstream molecules Src and interleukin-1β (IL-1β) in PTECs. AICAR further alleviated high UA-induced apoptosis, autophagy, and mitochondrial dysfunction. Although AMPK activation by metformin did not reduce serum UA levels in hyperuricemic rats, it significantly alleviated HUA-induced renal tubular injury and NKA signaling impairment in vivo with effects similar to those of febuxostat. Our study suggests that AMPK activation may temporarily compensate for HUA-induced renal injury. Sustained AMPK activation could reduce lysosomal NKA degradation and maintain NKA function, thus alleviating NKA downstream inflammation and protecting tubular cells from high UA-induced renal tubular injury., Kidney damage: Identifying mechanisms behind uric acid effects High serum levels of uric acid cause kidney tissue damage through cellular processes that have now been identified by researchers in China. Uric acid is a common component of urine, but causes damage if it is present in high levels in the blood (hyperuricemia). While investigating the mechanisms behind hyperuricemia, Zhibin Ye and co-workers at Fudan University in Shanghai recently showed that impairment of the Na+-K+-ATPase (NKA) signaling pathway, which regulates uric acid transportation through the kidneys, is a crucial feature of renal damage progression. The team have now shown that NKA is regulated by the AMP-activated protein kinase (AMPK) pathway, and that AMPK is enriched during the initial phases of hyperuricemia. Studies on rat models indicated that sustained AMPK activation restored NKA signaling, limiting damage from hyperuricemia.

The targeted delivery of a photosensitizer (PS) into specific cancer cells is an effective way to enhance the efficacy and minimize the side effects of photodynamic therapy. Herein, heptamannosylated β-cyclodextrin (β-CD) was used to mediate the formation of an adamantane (Ad)-functionalized BODIPY PS nanoparticle via strong β-CD/Ad complexation. The mannose-functionalized PS nanoparticles are selectively internalized by mannose-receptor-rich MDA-MB-231 breast cancer cells via receptor-mediated endocytosis, facilitating singlet oxygen generation to trigger apoptosis in cancer cells upon red-light irradiation. These nanoparticles exhibit excellent targeted delivery of the PS, leading to cancer cell death after irradiation both in vitro and in vivo.

The intermediate-conductance Ca2+-activated K+ (KCa3.1) channel plays a vital role in myocardial fibrosis induced by angiotensin (Ang) II. However, as the antagonists of Ang II, the effect of angiotensin-converting enzyme 2 (ACE2)-angiotensin-(1-7)-Mas axis on KCa3.1 channel during myocardial fibrosis remains unknown. This study was designed to explore the function of KCa3.1 channel in the cardioprotective role of ACE2-Ang-(1-7)-Mas. Wild-type (WT) mice, hACE2 transgenic mice (Tg), and ACE2 deficiency mice (ACE2-/-) were administrated with Ang II by osmotic mini-pumps. As the activator of ACE2, diminazene aceturate (DIZE) inhibited increase of blood pressure, collagen deposition, and KCa3.1 protein expression in myocardium of WT mice induced by Ang II. In Tg and ACE2-/- mice, besides the elevation of blood pressure, Ang II induced transformation of cardiac fibroblast into myofibroblast and resulted in augmentation of hydroxyproline concentration and collagen deposition, as well as KCa3.1 protein expression, but the changes in ACE2-/- mice were more obvious than those in Tg mice. Mas antagonist A779 reduced blood pressure, myocardium fibrosis, and myocardium KCa3.1 protein expression by Ang II in Tg mice, but activation of KCa3.1 with SKA-31 in Tg mice promoted the pro-fibrogenic effects of Ang II. Respectively, in ACE2-/- mice, TRAM-34, the KCa3.1 blocker, and Ang-(1-7) inhibited increase of blood pressure, collagen deposition, and KCa3.1 protein expression by Ang II. Moreover, DIZE and Ang-(1-7) depressed p-ERK1/2/t-ERK increases by Ang II in WT mice, and after blockage of ERK1/2 pathway with PD98059, the KCa3.1 protein expression was reduced in WT mice. In conclusion, the present study demonstrates that ACE2-Ang-(1-7)-Mas protects the myocardium from hypertension-induced injury, which is related to its inhibiting effect on KCa3.1 channels through ERK1/2 pathway. Our results reveal that KCa3.1 channel is likely to be a critical target on the ACE2-Ang-(1-7)-Mas axis for its protective role in myocardial fibrosis and changes of KCa3.1 induced by homeostasis of ACE-Ang II-AT1 axis and ACE2-Ang-(1-7)-Mas axis may be a new therapeutic target in myocardial fibrosis.

Our study aims to explore the role of microRNA‐181b (miR‐181b) and TLR in the regulation of cell proliferation of human epidermal keratinocytes (HEKs) in psoriasis. Twenty‐eight patients diagnosed with psoriasis vulgaris were selected as a case group with their lesional and non‐lesional skin tissues collected. A control group consisted of 20 patients who underwent plastic surgery with their healthy skin tissues collected. Real‐time quantitative fluorescence polymerase chain reaction (RT‐qPCR), in situ hybridization and immunohistochemistry were used to detect the expressions of miR‐181b and TLR4 in HEKs of healthy skin, psoriatic lesional skin and non‐lesional skin respectively. The 3′ untranslated region (3′UTR) of TLR4 combined with miR‐181b was verified by a dual‐luciferase reporter assay. Western blotting and bromodeoxyuridine were applied for corresponding detection of TLR4 expression and cell mitosis. The expression of miR‐181b in HEKs of psoriatic lesional skin was less than healthy skin and psoriatic non‐lesional skin. In psoriatic lesional and non‐lesional skin, TLR4‐positive cell rates and the number of positive cells per square millimetre were higher than healthy skin. The dual‐luciferase reporter assay verified that miR‐181b targets TLR4. HEKs transfected with miR‐181b mimics had decreased expression of TLR4, along with the decrease of mitotic indexes and Brdu labelling indexes. However, HEKs transfected with miR‐181b inhibitors showed increased TLR4 expression, mitotic indexes and Brdu labelling indexes. HEKs transfected with both miR‐181b inhibitors and siTLR4 had decreased mitotic indexes and Brdu labelling indexes. These results indicate that miR‐181b can negatively regulate the proliferation of HEKs in psoriasis by targeting TLR4.

The hybrid anatase/rutile TiO2 hierarchical nanorods (ARTHNs) with exposed specific faces have been facilely synthesized by one-step hydrothermal reaction. Powder X-ray diffraction and Raman studies confirm the mixed bicrystalline phase of anatase and rutile in ARTHNs. Scanning electron microscopy clearly shows the morphologies of ARTHNs were hierarchical nanorods with lengths of about 2–5 μm and diameters of around 300 nm, and transmission electron microscopy analysis further indicate that ARTHNs are composed of central rutile nanorods and external anatase nanosheets with both of exposed (010) facets. Due to the exposed (010) facets in hybrid phase of ARTHNs, they exhibit a higher lithium storage performance than the commercial analogue P25.

A highly porous metal-organic framework (MOF) incorporating both exposed metal sites and nitrogen-rich triazole groups was successfully constructed via solvothermal assembly of a clicked octcarboxylate ligand and Cu(II) ions, which presents a high affinity toward CO2 molecules clearly verified by gas adsorption and Raman spectral detection. The constructed MOF featuring CO2-adsorbing property and exposed Lewis-acid metal sites could serve as an excellent catalyst for CO2-based chemical fixation. Catalytic activity of the MOF was confirmed by remarkably high efficiency on CO2 cycloaddition with small epoxides. When extending the substrates to larger ones, its activity showed a sharp decrease. These observations reveal that MOF-catalyzed CO2 cycloaddition of small substrates was carried out within the framework, while large ones cannot easily enter into the porous framework for catalytic reactions. Thus, the synthesized MOF exhibits high catalytic selectivity to different substrates on account of the confinement of the pore diameter. The high efficiency and size-dependent selectivity toward small epoxides on catalytic CO2 cycloaddition make this MOF a promising heterogeneous catalyst for carbon fixation.

Supramolecular hyperbranched polymers have been successfully constructed by using host-enhanced π–π interactions between CB[8] and a naphthyl-substituted tetraphenylethene derivative, which exhibit a strong fluorescence in aqueous solution due to aggregation-induced emission.

AIE-active luminogen tetraphenylethene (TPE) was incorporated into a UiO-isoreticular zirconium metal-organic framework via the strategy of mixed dicarboxylate struts, and the resulting functionalized MOF shows a strong blue-green emission and selective sensing of nitroaromatic explosives 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP) through fluorescence quenching. Moreover, the luminescent MOF exhibits efficient photocatalytic activity for aerobic cross-dehydrogenative coupling reactions mediated by visible light.

Nitrogen-rich metal–organic framework (N-MOF) nanocrystals with concave surfaces at exposed [100, 001] directions were synthesized via a facile wet-chemical route. The 1-methylimidazole modulator plays an essential role in controlling the morphology and size of cubic N-MOF nanocrystals. Compared with octahedron and cuboctahedron morphologies, the cubic N-MOF shows significantly enhanced gas uptake capability due to having more open metal sites and coordination-free triazole moieties.

The organic photosensitizer diiodo-BODIPY has been covalently conjugated into a Zr(IV)-based metal–organic framework with UiO topology via postsynthetic modification, which serves as a highly active and recyclable heterogeneous photocatalyst for aerobic cross dehydrogenative coupling and oxidation/[3 + 2]cycloaddition reactions under visible light irradiation.