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We present a Holocene record of pyrolytic nitrogen (N) composition from the Jinchuan peat bog within the Longgang Volcanic Field (LVF), NE China. Based on pyrolysis gas chromatography and mass spectrometry (Py-GC/MS) analysis, N-compounds including acetamide, NHetero and NAro have been identified and quantified. Aromatic N-compounds (NAro, benzonitrile and benzamide) are mainly derived from phytoplankton and higher plants, and are resistant to microbial degradation. We propose ‘NHetero/NAro’ as a proxy based on microbial degradation, and has lower values between 10 and 5.8 ka BP, and higher values during the late Holocene. We suggest that temperature is main factor for NHetero/NAro, and sedimentary facies changed from floodplain to peat deposition, variation of effective precipitaion and pH value have limited influence on the performance of the proxy in Jinchuan. Low NHetero/NAro levels, combined with high levels of non-protein derived acetamide, indicate warmer conditions, and vice versa. NHetero/NAro is sensitive to temperature change, and follows a similar pattern to those of previous paleo-temperature time series derived from br-GDGT and long chain alkenones in this region. This Spectral analysis of the NHetero/NAro time series reveals significant periodicities of 103–105, 145 and 482–506 years, suggesting strong influences of solar radiation and monsoon intensity on temperature variations in NE China during the Holocene.

Carbon materials hold the great promise for application in energy storage devices owing to their low cost, high thermal/chemical stability, and high electrical conductivity. However, it remains challenging to synthesize high-performance carbon electrodes in a simple, scalable and sustainable way. Here, we report a facile method for scalable synthesis of porous carbon anode by using cheap and easily accessible zeolitic imidazolate framework-8 as a template and polyvinylpyrrolidone as an additional carbon source. The obtained porous carbon shows the macroscopic sheet-like morphology, which has the highly disordered structure, expanded interlayer spacing, abundant pore structure, and nitrogen doping properties. This porous carbon anode is demonstrated to have the excellent K+ charge storage properties in specific capacity, rate capability, and cycling stability. A potassium-ion capacitor assembled by using this porous carbon as the anode, delivers a maximum energy density of 85.12 Wh/kg and power density of 11860 W/kg as well as long cycle life exceeding 3000 cycles. This represents a critical advance in the design of low cost and scalable carbon material for applications in energy storage devices.

We have developed a metal-free radical cascade reaction of N-substituted 2-aryl indoles with readily available sulfonyl hydrazides for the rapid construction of arylsulfonyl-substituted indolo[2,1-a]isoquinolin-6(5H)-one derivatives. With the TBAI–TBHP catalytic system, a broad series of structurally diverse indolo[2,1-a]isoquinolin-6(5H)-one derivatives were obtained in moderate to excellent yields. The reaction features mild reaction conditions, operationally easiness, scaled-up feasibility, and high functional-group-tolerance.

The aqueous Zinc-base batteries such as the Zn-air battery and the Zn-ion battery, featured with low-cost, high safety, high specific capacity and environmental-friendliness, have attracted intensive attention for energy storage. For high performance Zinc-base batteries, the electrocatalysts with good conductivity, convenient mass transfer path and adequate accessible active sites are demanded. Herein, we have fabricated transition-metal/nitrogen co-doped honeycomb-like carbon materials with hierarchical porous structure through a freeze-drying and one-step pyrolysis method. The as-prepared FeZnN-C are used as cathode materials of Zinc-air battery, the Zinc-air battery displays high peak power density of 257 mW cm-2, superior discharging voltage platform around 1.36 V and large specific capacity of 785 mAh gZn-1. Meanwhile, the prepared Zn/ZnN-C was used as anode of a Zinc-ion battery which exhibits great cycle stability and high charging/discharge rate. Our work provides a novel and facile method to construct highly efficient electrocatalysts with hierarchical macro-meso-micro-porous structure and multi-active sites for application in the aqueous Zinc-base batteries.

As the heaviest group 12 element known now, copernicium (Cn) often presents the oxidation states of +I, +II, and rarely +IV as in its homologue mercury. In this work we systematically studied the stability of some oxides, fluorides, and oxyfluorides of Cn by two-component relativistic calculations, and found that the CnF6 molecule with an oxidation state of +VI has an extraordinary stability. CnF6 may decompose into CnF4 by conquering an energy barrier of about 30 kcal/mol without markedly releasing heat. Our results indicates that CnF6 may exist under some special conditions.

Glucokinase (GK) and PPARγ are important targets for antidiabetic use. Silybin is one of the major active ingredients of Silybum marianum. The regioselective modification of the five hydroxyl groups in the silybin structure has always been a challenge. In this study, we found that silybin was an agonist of GK and PPARγ. A novel synthesis scheme of silybin derivatives was designed, and a series of novel silybin derivatives has been synthesized. The derivative 8d showed relatively strong activation activity for GK and PPARγ in enzyme activity and transactivation assays (GK activation fold: 1.86; PPARγ transactivation activation percentage: 90.32%). This research suggests that silybin and its derivatives could be used as novel GK and PPARγ dual-target agonists.

Histone deacetylase 6 (HDAC6) is a potential therapeutic target for treating several diseases. A recent study revealed that HDAC6 is important for NLRP3 inflammasome activation, suggesting that targeting HDAC6 could be useful for treating many inflammatory disorders. Using the proteolysis targeting chimera (PROTAC) strategy, we herein report an HDAC6 degrader with low cytotoxicity by tethering a selective HDAC6 inhibitor derived from a natural product, indirubin, with pomalidomide, a CRBN E3 ligand. Our HDAC6 degrader efficiently and selectively decreased HDAC6 levels in several cell lines, including activated THP-1 cells. Application of this HDAC6 degrader attenuated NLRP3 inflammasome activation in LPS-induced mice, which for the first time demonstrates that HDAC6 PROTAC could be a novel strategy to treat NLRP3 inflammasome-associated diseases.

Methyltransferase like 3 (METTL3) has been identified to serve as a definitive inducer in cancer progression. This study sought to analyze the regulatory mechanism of METTL3 in epithelial-mesenchymal transition (EMT), invasion, and metastasis in esophageal cancer (ESCA). The METTL3 expressions in cancer tissues and cells were detected with extensive analysis of its correlation with clinical baseline data. The cells were transfected with sh-RNA-METTL3 and microRNA (miR)-20a-5p mimic, followed by evaluation of invasion, migration, and EMT. The N6-methyladenosine (m6A) level and enrichment of DiGeorge Critical Region 8 (DGCR8) and m6A were observed. The binding relationship between miR-20a-5p and Nuclear Factor I-C (NFIC) was verified, followed by Pearson correlation analysis. A subcutaneous tumor formation assay was conducted prior to observation of lung metastases. Our results revealed that METTL3 was highly expressed in ESCA patients and associated with severe lymph node involvement and distant metastasis. METTL3 downregulation radically inhibited the invasiveness, migration, and EMT. METTL3 elevated the miR-20a-5p expression via improving m6A modification. METTL3 inhibition downregulated the miR-20a-5p expression. Moreover, miR-20a-5p upregulation facilitated ESCA cell invasiveness and migration by targeting NFIC transcription. METTL3 inhibition suppressed tumor growth and lung metastasis in vivo. Overall, METTL3 promoted m6A modification and the binding of DGCR8 to miR-20a-5p to further elevate the miR-20a-5p expression and inhibit NFIC transcription, thus promoting EMT, invasion and migration.

A mild and efficient method for the cobalt-catalyzed hydroxyperfluoroalkylation of alkenes has been developed. This method demonstrated broad substrate scope, good yields, and mild conditions with the tolerance of mono-, di-, and trisubstituted alkenes including both styrenes and non-activated aliphatic olefins. This strategy offered a valuable solution for rapid and efficient construction of β-perfluoro­alkyl alcohols using widely available and inexpensive perfluoroalkyl bromides­ and atmospheric oxygen.

A safer and more effective combination strategy designed to enhance the efficacy and minimize the toxicity of cisplatin in osteosarcoma (OS) is urgently needed. Zeylenone (zey), a cyclohexene oxide compound, exerted an obvious inhibitory effect on several cancer cell lines and exhibited little cytotoxicity towards normal cells, enabling zey to play a unique role in combination therapy. Thus, the study aimed to determine whether the combination of zey and cisplatin produces synergistic antitumour effects on OS and to further explore molecular mechanisms. Initially, we found that zey potentiated the anti-osteosarcoma efficacy of cisplatin and exhibited synergistic interactions with cisplatin in vitro, which also were confirmed in vivo by using xenograft model. Mechanistically, zey and cisplatin synergistically induced DNA damage, cell cycle arrest, necrosis, and apoptosis in OS cells. Importantly, zey had a high binding affinity for Hsp90 and reduced the expression of Hsp90, which further induced the suppression of AKT/GSK3β signalling axis and the degradation of Fanconi anaemia (FA) pathway proteins. Thus, the Hsp90/AKT/GSK3β and FA pathway are the key to the synergism between zey and cisplatin. Overall, zey shows promise for development as a cisplatin chemosensitizer with clinical utility in restoring cisplatin sensitivity of cancer cells.

We have developed cobalt-catalyzed, bidentate 2-(1-methylhydrazinyl)pyridine (MHP)-directed C(sp2)-H alkylation/annulation of benzoic hydrazides with various alkenes. Notably, diverse cyclopenta[c]isoquinolinones and dihydroisoquinolinones were obtained via this functional group-tolerant protocol. The reaction can be performed on a gram scale while maintaining an excellent yield, and the directing group can be removed efficiently under mild conditions. Furthermore, density-functional theory (DFT) calculations provide an incisive understanding of the observed regioselectivities for different olefins.

Adjusting the local coordination environment of lanthanide luminescent ions is a useful method to manipulate the relevant photoluminescence (PL) property. K3Lu(PO4)2 is a phase-change material, and according to the stable temperature range from low to high, the related polymorphs are phase I [P21/m, coordination number (CN) of Lu3+ = 7], phase II (P21/m, CN = 6), and phase III (P3, CN = 6), respectively. Based on the temperature-dependent PL analysis of K3Lu(PO4)2:Pr3+, we find that Pr3+ ions occupy the noninversion sites (Cs) in the two low-temperature phases but preferentially enter into the inversion ones (C3i) in phase III. Compared to Pr3+-doped phase I (78 K), Pr3+ ions in phase III (300 K) manifest a weaker fluorescence intensity (170-fold lower). To enhance the room-temperature PL property of K3Lu(PO4)2:Pr3+, a polymorphous adjustment strategy was proposed by the use of the ion-doping method. By introducing the Gd3+ ions into the lattice, Pr3+-doped phase I is successfully stabilized to room temperature, manifesting a 27-fold fluorescence increase in comparison to K3Lu(PO4)2:Pr3+ (0.1 at. %). The finding discussed in this study highlights the significance of site engineering for luminescent ions and also presents the application value of phase-change hosts in the development of high-performance luminescent materials.

Palladium-catalyzed C(sp2)-H arylation of ortho C-H bonds involving 2-(1-methylhydrazinyl)pyridine (MHP) as the directing group has been investigated. The reaction proceeds smoothly under an air atmosphere to generate biaryl derivatives in an environmentally friendly manner while tolerating a wide range of functional groups. Notably, the directing group present in the product could be easily removed under mild reductive conditions.

The characterization of ferroelectricity in ultra-thin ferroelectric (FE) films is highly challenging due to enlarged leakage current and resistive switching (RS) effect. In this study, we investigated the polarization switching properties of 1.5-nm thick Hf0.5Zr0.5O2 (HZO) films via direct hysteresis remnant polarization/voltage (P–V) loop measurement. To reduce the leakage current and eliminate the RS effect, positive-up–negative-down (PUND) measurement was implemented on back-to-back connected complementary cells. Rational hysteresis loops, with remnant polarization of approximately $2~\mu \text{C}$ /cm2, were successfully obtained by directly measuring the polarization switching currents. In this study, we provide direct evidence of the stable ferroelectric property in 1.5-nm thick HZO films, and thereby show a potential prospect of ultimate scalability of HZO films.

The aim of this study was to evaluate effects of Bacillus licheniformis supplementation on growth, intestine digestive, antioxidant and metabolic capacity, intestine short-chain fatty acids content, and intestine microbiota composition of the Pacific white shrimp Litopenaeus vannamei. In total 2700 shrimp (initial weight 2.5 ± 0.1 g/shrimp) were randomly distributed into six tanks (450 shrimp/500-L tank) and fed at 28 ± 0.5 ℃ for 35 days (four times/day) with control diet and experimental diet supplemented with 108 CFU/g B. licheniformis, followed by an acute nitrite stress for 10 days. At the end of the feeding trial, shrimp dietary B. licheniformis showed improved weight gain, specific growth rate, survival rate after nitrite stress, and decreased feed conversion rate compared to control group. And acetic acid and butyric acid content in the intestine of shrimp dietary B. licheniformis increased significantly except for propionic acid content. In addition, activities of amylase, lipase, and trypsin and activities of glutamine synthetase, hexokinase, and malate dehydrogenase increased significantly compared to control group. After shrimp were exposed to nitrite stress for 10 days, glutathione peroxidase, peroxidase, total antioxidant capacity, and superoxide dismutase levels were still higher in dietary B. licheniformis-shrimp, which showed that B. licheniformis enhanced the resistance to environmental stressor such as nitrite from the level of immune. The 16S rRNA sequencing showed that B. licheniformis increased diversity and abundance of some bacteria. In particular, the abundance of Proteobacteria and Planctomycetes decreased, and the abundance of Firmicutes and Bacteroidetes increased. These results revealed that B. licheniformis could improve the growth performance, increased intestine short-chain fatty acids (SCFA) content, change intestine digestive and metabolic enzyme activity, and regulated microbiota composition, so enhance the intestine antioxidant ability of shrimp subjected to nitrite stress, which is beneficial for shrimp aquaculture.

Fluorophores with emission in the second near-infrared window (NIR-II) have displayed salient advantages for biomedical applications. However, the common strategy of reducing the energy bandgap of fluorophores so as to achieve red-shifted wavelengths always leads to compromised fluorescent brightness. Herein, we propose a molecular design concept of "ring-fusion" to modify the acceptor of AIEgen that can extend the luminous wavelength from NIR-I to NIR-II. The fused-acceptor-containing fluorophore yielded, TTQP, has an enhanced absorption coefficient with a higher brightness in nanoparticle formation compared to its NIR-I emissive counterpart (TTQ-DP) with a non-fused acceptor. Theoretical calculation further confirms that the ring fusion can efficiently promote the rigidity and planarity of the electron-deficient core, leading to a lower reorganization energy and nonradiative decay. The TTQP NPs yielded thus allow sensitive NIR-II fluorescence imaging of vasculature and intestinal inflammation in mice models. Therefore, we anticipate that our work will provide a promising molecular-engineering strategy to enrich the library and broaden the application scope of NIR-II fluorophores.

We aimed to investigate whether phloridzin could alleviate nonalcoholic fatty liver disease (NAFLD) in mice, which was induced by feeding a high-fat diet (HFD). We initially analyzed the effect of phloridzin on alleviating HFD-induced NAFLD in C57BL/6J mice and oleic acid (OA)-stimulated human normal liver L-02 cells (L02). Then, we investigated the mechanism of phloridzin on the mTORC1/sterol-regulatory element-binding protein-1c (SREBP-1c) signaling pathway by siRNA analysis, qRT-PCR, flow cytometry, and western blot analysis in vivo and in vitro. The results revealed that phloridzin significantly inhibited the increase in body weight, alleviated abnormal lipid metabolism, and decreased lipid biosynthesis and insulin resistance. Moreover, phloridzin augmented the number of CD8+CD122+PD-1+ Tregs and CD4+FoxP3+ Tregs in HFD-fed C57BL/6J mice and HFD-fed aP2-SREBF1c mice and downregulated the mTORC1/SREBP-1c signaling pathway-related protein expressions in vivo and in vitro. Furthermore, phloridzin reduced the expression of SREBP-1c in SREBP-1c-RNAi-lentivirus-transfected L02 cells and reversed the SREBP-1c expression in HFD-fed aP2-SREBF1c transgenic mice. Phloridzin ameliorates lipid accumulation and insulin resistance via inhibiting the mTORC1/SREBP-1c pathways. These results indicated that phloridzin may actively ameliorate NAFLD.

A pyridinium salt catalyzed radical borylation of benzoyl peroxides is reported herein. A range of benzoyl peroxides having different electronic properties were well compatible in this borylation reaction, delivering various arylboronates in good yields at ambient temperature. The current method features simple operation, additive- and base-free, transition-metal-free and mild conditions.

In the present work, WO3 nanosheets(WO3 NSs) were prepared by a facile method at room temperature. The obtained WO3 NSs showed peroxidase-like activity, which could catalyze 3,3’,5,5’-tetramethylbenzidine(TMB) to form a blue oxidation product(ox TMB) in the presence of H2O2. Based on this, convenient and sensitive colorimetric methods for the detection of H2O2 and glucose were established. The linear ranges for detecting H2O2 and glucose were 1–200 µmol/L and 1–100 µmol/L, respectively. The limits of the detection of H2O2 and glucose were as low as 0.79 and 0.96 µmol/L, respectively. This method was also successfully applied to the detection of glucose in urine samples. The detection result was consistent with that of the value detected by the clinical method, indicating the potential in clinical diagnosis and biomedical detection.

Extraction of uranium from radioactive waste-water is of significant importance for environmental protection and the recovery of uranium resource. Different from the previous reports to use the solid absorbent/photocatalyst for U(VI) removal, herein, we proposed a new eco-friendly method for the rapid and selective extraction of uranium from aqueous solutions under visible light without solid materials. At optimal pH value and in the presence of organics like alcohols, the U(VI) could be extracted efficiently to form brown uranium solid over wide uranium concentrations under anaerobic condition and visible light, by utilizing the excitation of the given U(VI) species. With comprehensive modelling of the electronic ultraviolet-visible (UV-Vis) properties, it is proved that pH adjusting towards U(VI) could induce efficient ligand-to-metal-charge-transfer (LMCT) within the uranyl complex under visible light and the reduction of U(VI) to form U(V), which can be transformed into U(IV) via disproportionation reaction. The resulting U(IV) in solid phase makes the extraction much more convenient in operation. More importantly, the excellent selectivity for uranium extraction over interfering alkali metal ions, transition metal ions and the lanthanide metal ions shows a powerful application potential.

The rapid and effective removal of organic micropollutants (OMPs) from water remains a huge challenge for traditional water treatment techniques. Compared with powder adsorbents such as polymers and nanomaterials, the free-standing adsorptive membrane is possible for large-scale applications and shows promise in removing OMPs. Herein, inspired by aquatic plants, a novel free-standing adsorptive membrane (NPPM) with high water flux, strong adsorption affinity, and excellent reproducibility was prepared by one-step UV surface grafting. N-Vinylformamide (NVF) was employed to introduce multiple hydrophilic and hydrogen bonding sites on the surface of commercial polypropylene fiber membranes (PPM). The NPPM exhibits excellent water permeability and ultrahigh water flux (up to 40 000 L/(m2 h)) and could continuously remove a broad spectrum of OMPs from water. Its adsorption performance is 5-100 times higher than that of PPM and commercial membranes. Even in natural water sources such as tap water and river water, the NPPM shows unchanged adsorption performance and high OMPs removal efficiency (>95%). Notably, the NPPM has excellent regeneration performance and can be regenerated by hot water elution, which provides an environmentally friendly regeneration method without involving any organic solvent. Moreover, the synergy between hydrogen bonding and hydrophobic interaction is revealed, and the hydrophobic interaction provided by the hydrophobic substrate is proved to play a fundamental role in OMPs adsorption. The strong hydrogen bonds between the grafts and the OMPs are demonstrated by variable-temperature FTIR spectroscopy (vt-FTIR), 13C nuclear magnetic resonance spectroscopy (13C NMR), and simulation calculations. The strong hydrogen bonds could increase the enthalpy change and enhance the adsorption affinity, so the NPPM has a strong adsorption affinity, which is 100 times that of similar adsorption membranes. This study not only presents an adsorptive membrane with great commercial potential in the rapid remediation of a water source but also opens a pathway to develop an adsorptive membrane with high water flux and strong adsorption affinity.

Gold nanocluster (AuNC) decorated hydrogels have attracted considerable attention as versatile biomaterials. To date AuNCs and hydrogels have mainly been mixed as independent components. Here, we report the use of AuNCs as reactive monomers in the polymerization of hydrogels. We used a free radical polymerization to copolymerize AuNCs with acrylamide and N-acryloyl glycinamide to prepare stimuli-responsive smart hydrogels. Multiple C═C bonds were decorated on the surface of the AuNCs as active sites for polymerization. These C═C bonds not only protected the structure of the AuNCs from oxidation by free radicals during polymerization but also covalently connected the AuNCs with the polymer chains. This structure ensured good photothermal performance of the AuNCs while preserving the thermoresponsive hydrogen bonds of polymers. Moreover, the copolymerized AuNCs acted as cross-linkers, which improved the mechanical properties of the hydrogels. These smart hydrogels had good stability, efficient photothermal conversion, and a sensitive thermoresponsive. We examined their potential for capture of MDA-MB-231 cells with hyaluronic acid as target molecules. The captured cells were released under 660 nm irradiation. This process of targeted capture and light-controlled remote release could be repeatedly applied. These results suggest that systems based on AuNCs copolymerized with hydrogels have great potential for biomedical applications.

A sticky-flare gold nanoparticle probe (AuNP-probe) is designed by the combination of locked nucleic acid functionalized silencing of microRNA technology for intracellular microRNA-21 (miRNA-21) sensitively detecting, fluorescence imaging, localizing and silencing. The limit of detection is as low as 0.01 nM. Overexpressed miRNA-21 in cancer cells serves as endogenous drug release stimuli to trigger the release of probe-loaded doxorubicin (Dox), which soon translocates into cell nuclei. This multifunctional Dox-loaded AuNP-probe (Dox-AuNP-probe) could induce cancer cell apoptosis effectively through the synergistic effect of gene silencing and chemotherapy. This Dox-AuNP-probe exhibits superior drug potency compared to free Dox molecules, with a cell inhibition rate of 57% (but only 20% for Dox) to wild-type cancer cells and 30% (but 0% for Dox) to drug-resistent cancer cells after 72 h, and this strategy not only has the function of sensing, but also can effectively bypass drug resistance. In MCF-7 xenograft tumor-bearing mice, the Dox-AuNP-probes show greater inhibition for tumor tissues than miRNA-21 targeted AuNP-probes (Targeting-AuNP-probe) or free Dox molecules. Therefore, the Dox-AuNP-probe represents a promising nanotheranostic platform for future applications in cancer molecular imaging and therapy, especially providing a potential strategy to treat resistant cancers.

Aqueous Zn-ion batteries (ZIBs) have acquired the researchers' curiosity owing to their harmlessness, cost effectiveness and high theoretical capacity of Zn anode. However, desirable cathode materials with high-capacity and high-rate are still scarce. In this work, the formation of carbon quantum dots induced vanadium pentoxide nanobelts was demonstrated via a facile one-step hydrothermal method for ZIBs. It exhibited an excellent Zn ion storage capacity of 460 mA h g-1 at 0.1 A g-1 , superior rate capability and stable cycling performance (above 85 % capacity retention over 1500 cycles at 4 A g-1 ). The electrochemical kinetics and zinc ion storage mechanism were also considered. An efficient architecture-coupled valence engineering in the hybrid cathode was proposed to improve the electric conductivity, Zn ion diffusion rate, and cycling stability for ZIBs. This work may be a great motivation for further research on V2 O5 or other vanadium-based materials for high-performance ZIBs.

Nitrogen-doped carbon nanotubes (N-CNTs) were synthesized via a hydrothermal method and further modified with magnetic Co0.5Cu0.5Fe2O4 nanoparticles following a one-pot solvothermal method. The characterization data show that the distribution of the magnetic materials and the adsorption characteristics of the CNTs can be tailored as a function of the N doping amount. The N-CNT adsorption isotherms as a function of N content and chlorophenol uptake show that a N doping level of 6% is optimum. After loading the N-CNTs with the magnetic Co0.5Cu0.5Fe2O4 nanoparticles (M-N-CNTs), the resulting materials were easily dispersed in aqueous media with specific surface area reaching 95.64 m2/g. The M-N-CNTs exhibit high affinities toward the adsorption of different chlorophenols following the order: Pentachlorophenol (PCP) > 2,4,6-trichlorophenol (2,4,6-TCP) > 2,4-dichlorophenol (2,4-DCP) > 2,4-dichlorophenoxyacetic acid (2,4-D) > phenol. Additionally, the M-N-CNTs exhibit good microwave absorption performance and can be regenerated by microwave irradiation with high efficiencies (> 90%) maintained with high stabilities.

Sodium ion batteries (SIBs) are regarded as a promising alternative to lithium ion batteries, while their application is hindered by the lack of good anode materials. Integrating morphology, struct...

The mesoporous nanostructures of cobalt-doped (Co-doped) manganese oxides (MnOx) with controllable compositions are successfully synthesized by a facile inverse micelle sol-gel method. It can be found that with the addition of cobalt ions, the Mn-Co two-element spinel structure oxide is formed. Moreover, as the amount of cobalt ions increases, the shape of the agglomeration changes from rod to approximately spherical particles, and its average pore size decreases gradually, which is conducive to improve the specific surface area of the as-prepared product. The electrochemical measurements show that the specific capacitance of as-prepared mesoporous samples increases with the rise of Co-doped content. In particular, when the molar ratio of Mn/Co is 10:5, the synthesized mesoporous CoMn2O4 nanoparticles exhibit a high specific capacitance of 614.8 F g−1 at 1 A g−1. The final capacitance can still maintain 82.4% of the initial capacitance at 5 A g−1 after 5000 cycles. Furthermore, asymmetric supercapacitor assembled by CoMn2O4 and activated carbon also exhibits high energy density (29.5 Wh kg−1 at 799.7 W kg−1), high power density (8.0 kW kg−1 at 3.2 Wh kg−1) and excellent cycle stability (84.3% capacitance retention rate after 5000 cycles). The mesoporous CoMn2O4 with superior electrochemical performance has great potential in the application of high-performance supercapacitors.

Nitric oxide (NO) is a gaseous signal molecule with multiple physiological functions, and it also plays a key role in cancer therapy. However, the production of NO which depends on O2 or H2 O2 is limited within the tumor microenvironment, leading to unsatisfactory anticancer effect. Herein, we report a NO-based phototherapeutic strategy mediated by photogenerated holes for hypoxic tumors, which is achieved by irradiation of the poly-L-arginine modified carbon-dots-doped graphitic carbon nitride nanomaterial (ArgCCN). Upon red light irradiation, the photogenerated holes on ArgCCN oxidized water into H2 O2 which subsequently oxidized the arginine residues to produce NO. In vitro and in vivo experiments showed that the high concentration of NO produced by ArgCCN could induce cancer cell apoptosis. The presented phototherapeutic strategy is based on microenvironment-independent photogenerated holes mediated oxidation reaction, paving the way for the development of NO therapeutic strategy.

Less than 40% of the nitrogen (N) fertilizer applied to soil is absorbed by crops. Thus, improving the N use efficiency of crops is critical for agricultural development. However, the underlying regulation of these processes remains largely unknown, particularly in woody plants. By conducting yeast two-hybrid assays, we identified one interacting protein of MdMYB88 and MdMYB124 in apple (Malus × domestica), namely BTB and TAZ domain protein 2 (MdBT2). Ubiquitination and protein stabilization analysis revealed that MdBT2 ubiquitinates and degrades MdMYB88 and MdMYB124 via the 26S proteasome pathway. MdBT2 negatively regulates nitrogen usage as revealed by the reduced fresh weight, dry weight, N concentration, and N usage index of MdBT2 overexpression calli under low-N conditions. In contrast, MdMYB88 and MdMYB124 increase nitrate absorption, allocation, and remobilization by regulating expression of MdNRT2.4, MdNRT1.8, MdNRT1.7, and MdNRT1.5 under N limitation, thereby regulating N usage. The results obtained illustrate the mechanism of a regulatory module comprising MdBT2–MdMYB88/MdMYB124–MdNRTs, through which plants modulate N usage. These data contribute to a molecular approach to improve the N usage of fruit crops under limited N acquisition.

In this brief, the contact etch stop layer (CESL) stressor is introduced to improve the performance of n-type lateral double-diffused MOSFET (nLDMOSFET) with various operating voltages. Three groups of nLDMOSFETs were studied to demonstrate the effects of the CESL stressor. The electrical properties were carefully characterized, and the tip-enhanced Raman spectroscopy measurements were carried out to examine the process-induced strain directly. It is found that nLDMOSFETs with the strained SiN CESL have larger output current, transconductance ( ${g} _{m}$ ), and higher breakdown voltage (BV). The strained SiN CESL introduces tensile strain in the device and results in the performance boosts, which are verified by negative Raman peak shift mappings and TCAD simulations. The strained SiN CESL could effectively decrease the specific ON-resistance ( ${R} _{\text {on}}$ ) and improve the BV of the nLDMOSFET, due to the mobility enhancement.

Rationale: Glial scars present a major obstacle for neuronal regeneration after stroke. Thus, approaches to promote their degradation and inhibit their formation are beneficial for stroke recovery. The interaction of microglia and astrocytes is known to be involved in glial scar formation after stroke; however, how microglia affect glial scar formation remains unclear. Methods: Mice were treated daily with M2 microglial small extracellular vesicles through tail intravenous injections from day 1 to day 7 after middle cerebral artery occlusion. Glial scar, infarct volume, neurological score were detected after ischemia. microRNA and related protein were examined in peri-infarct areas of the brain following ischemia. Results: M2 microglial small extracellular vesicles reduced glial scar formation and promoted recovery after stroke and were enriched in miR-124. Furthermore, M2 microglial small extracellular vesicle treatment decreased the expression of the astrocyte proliferation gene signal transducer and activator of transcription 3, one of the targets of miR-124, and glial fibrillary acidic protein and inhibited astrocyte proliferation both in vitro and in vivo. It also decreased Notch 1 expression and increased Sox2 expression in astrocytes, which suggested that astrocytes had transformed into neuronal progenitor cells. Finally, miR-124 knockdown in M2 microglial small extracellular vesicles blocked their effects on glial scars and stroke recovery. Conclusions: Our results showed, for the first time, that microglia regulate glial scar formation via small extracellular vesicles, indicating that M2 microglial small extracellular vesicles could represent a new therapeutic approach for stroke.

The electrocatalytic CO2 reduction reaction (CO2RR) on copper-based catalysts is a promising method to produce valuable chemicals, but its selectivity is much lower than expected largely due to insufficient research on the structure of new materials. Herein, the antimony-doped Cu/Cu2O (Cu/Cu2O–Sb) catalyst is developed for a highly selective CO2RR to CO. The synthesized Cu/Cu2O–Sb exhibits intensive suppression of hydrogen evolution, a low overpotential and high faradaic efficiency (FE) towards CO. The CO selectivity is as high as ∼95% with a partial current density of ∼6.3 mA cm−2 at −0.9 V and maintains over 90% in a broad range of potentials. DFT calculations reveal that the doping of antimony achieves the distinct activation of CO2 and suppression of hydrogen evolution. Meanwhile, the pre-adsorbed *CO significantly promotes the desorption of the neighboring *CO, which is the key for high selectivity of CO2RR to CO. This work will provide a new consideration for the origin of high selectivity during the CO2RR and pave the way toward design of highly selective CO2 reduction catalysts.

The gaseous microenvironment (GME) of tumors is rapidly becoming a new concern for nanotechnology-mediated oncotherapy. Here, we constructed a tumor/near-infrared (NIR) light-responsive nanoplatform to generate O2 and NO for remodeling the GME of tumors and phototherapy. The biocompatible and pyrolytic polydopamine was used to load indocyanine green, NONOate, and MnO2 NPs as a nanoenzyme (PINM). Then, HA was modified on the PINM to form the final nanoplatform (PINMH). PINMH can target tumors favorably due to the modification of HA. Under the NIR light irradiation, PINM converts the light and O2 to hyperpyrexia (58.5 °C) and cytotoxic 1O2. MnO2 NPs catalyze the H2O2 overexpressed in tumors to O2, which increases the amount of 1O2. Moreover, NONOate decomposes to NO (100 μM) under hyperpyrexia, thus leading to the gas therapy. The results verified that the responsive nanoplatform with precise gaseous regulation and phototherapy exhibited a superior anti-tumor effect (V/V0 = 1.2) and biosafety. In addition, PINMH can be tracked in real-time via magnetic resonance imaging. In this study, an intelligent nano-platform integrated with diagnosis and treatment was developed, which used the phototherapy technology to reshape GME and achieve good anti-tumor effects, aiming to provide an innovative and reasonable strategy for the development of tumor treatment.

A series of novel 3,6-diamino-7,8-dihydroisoquinoline-4-carbonitrile (DDIC) derivatives were prepared from dicyanomethylene-4H-pyran derivatives and secondary amines by a mechanism of ring-opening and sequential ring-closing reactions. This reaction had the advantages of readily available materials, simple operations, mild reaction conditions, a broad substrate scope, and good yields. The DDIC derivatives displayed solid-state fluorescence with the emission wavelengths covering the whole visible light range, and the solid-state emissions were demonstrated to be ascribed to the twisted molecular conformations and loose stacking modes by crystal structural analyses. Among the compounds, 9aa exhibited a bathochromic mechanofluorochromic (MFC) phenomenon from blue to cyan due to increased molecular conjugation upon grinding, whereas 3aj and 3ka exhibited hypsochromic MFC activities with the color changing from orange to green and red to orange, respectively, because of decreased molecular conjugation, revealing that full-color-tunable emissions could also be realized by mechanofluorochromism. Furthermore, MFC-active molecules can be used in the field of encryption of important image or text information. Additionally, 3ka was demonstrated to emit single-molecular white fluorescence in organic solvents through the regulation of the concentration. The unexpected discovery of the DDIC derivatives provides a new possibility for the design and synthesis of novel isoquinoline-based fluorescent materials with excellent performance in the solid state.

CdS has been regarded as a promising visible-light-response photocatalyst in H2 production while its practical application is often limited by low photoactivity and serious photocorrosion. To tackle these problems, traditional CdS based core–shell and supported photocatalysts have been widely developed but they also suffer from intrinsic structural drawbacks. Herein, a novel stacked nanostructure with CdS embedded at interfaces between graphene supports and metallic MoS2 overlayers has been designed to eliminate the shortages and achieve outstanding photocatalytic performance, which reaches an optimum H2 production rate of 14.4 mmol gcat−1 h−1 and realizes an apparent quantum efficiency of 23.7% at 420 nm without obvious deterioration of activity in 20 h cyclic testing, far exceeding that of pure CdS by a factor of 17.9 times. The enhanced photocatalytic performance is mainly ascribed to the synergistic effects of MoS2 and graphene: (1) the intimate contact between the CdS core and MoS2 shell with a large interfacial area favors the transfer of photogenerated electrons to MoS2 cocatalysts, while a high-percentage 1T-phase provides an excellent electron mobility in the MoS2 cocatalysts and a high density of active sites for H2 evolution; (2) CdS cores are protected by MoS2 and graphene from photocorrosion, in which photogenerated holes are quickly transferred to the MoS2 shell and isolated from the sulfide surface, while excessive electrons in CdS are shuttled to adjacent MoS2 outer layers by graphene supports for H2 evolution in reducing their recombination with holes in the MoS2 shell and increasing the number of MoS2 sites available for the proton reduction reaction. The stacking design can be extended to the fabrication of other highly efficient photocatalytic systems.

Bone-forming osteoblasts have been a cornerstone of bone biology for more than a century. Most research toward bone biology and bone diseases center on osteoblasts. Overlooked are the 90% of bone cells, called osteocytes. This study aims to test the hypothesis that osteocytes but not osteoblasts directly build mineralized bone structures, and that defects in osteocytes lead to the onset of hypophosphatemia rickets. The hypothesis was tested by developing and modifying multiple imaging techniques, including both in vivo and in vitro models plus two types of hypophosphatemia rickets models (Dmp1-null and Hyp, Phex mutation mice), and Dmp1-Cre induced high level of β-catenin models. Our key findings were that osteocytes (not osteoblasts) build bone similar to the construction of a high-rise building, with a wire mesh frame (i.e., osteocyte dendrites) and cement (mineral matrices secreted from osteocytes), which is a lengthy and slow process whose mineralization direction is from the inside toward the outside. When osteoblasts fail to differentiate into osteocytes but remain highly active in Dmp-1-null or Hyp mice, aberrant and poor bone mineralization occurs, caused by a sharp increase in Wnt-β-catenin signaling. Further, the constitutive expression of β-catenin in osteocytes recaptures a similar osteomalacia phenotype as shown in Dmp1 null or Hyp mice. Thus, we conclude that osteocytes directly build bone, and osteoblasts with a short life span serve as a precursor to osteocytes, which challenges the existing dogma.

BODIPY dyes have recently been used for photothermal and photodynamic therapy of tumors. However, complex multi-material systems, multiple excitation wavelengths and the unclear relationship between BODIPY structures and their PTT/PDT efficiency are still major issues. In our study, nine novel BODIPY near-infrared dyes were designed and successfully synthesized and then, the relationships between BODIPY structures and their PTT/PDT efficiency were investigated in detail. The results showed that modifications at position 3,5 of the BODIPY core with conjugated structures have better effects on photothermal and photodynamic efficiency than the modifications at position 2,6 with halogen atoms. Density functional theory (DFT) calculations showed that this is mainly due to the extension of the conjugated chain and the photoinduced electron transfer (PET) effect. By encapsulating BDPX-M with amphiphilic DSPE-PEG2000-RGD and lecithin, the obtained NPs not only show good water solubility and biological stability, but also could act as superior agents for photothermal and photodynamic synergistic therapy of tumors. Finally, we obtained BODIPY NPs that exhibited excellent photothermal and photodynamic effects at the same time under single irradiation with an 808 nm laser (photothermal conversion efficiency: 42.76%, A/A0: ∼0.05). In conclusion, this work provides a direction to design and construct phototherapeutic nanoparticles based on BODIPY dyes for tumor treatment.

In the presence of K2S2O8 and HOAc, 3-(2-azidoaryl) substituted propargyl alcohols can go through chemoselective oxidative radical cyclizations to give a pool of anthranils based on Meyer-Schuster rearrangement. It's proposed that the cyclizations were triggered exclusively by the direct attack of oxygen radicals on the azides. The weak N-O bonds in anthranils could be easily cleaved in the presence of transition metal catalysts and went through aminations with 2-oxo-2-phenylacetic acid and iodobenzene.

Herein, we report the first oxygen (O2) and carbon dioxide (CO2) dual gas-switchable thermoresponsive polymers based on a newly synthesized monomer N-(2-fluoroethyl amide)-N-(2-(diethylamino)ethyl) acrylamide, that is, AM(F1EA-DEAE), which bears both O2-switchable fluorinated ethyl amide (F1EA) and CO2-switchable N,N-diethylamino ethyl (DEAE) moieties on its side chain. PolyAM(F1EA-DEAE) samples prepared from reversible addition–fragmentation chain transfer (RAFT) polymerization exhibited good temperature-responsive properties. Their inherent low critical solution temperature (LCST) could be reversibly tuned to different levels by respectively purging O2 or CO2 into its aqueous solution. The O2-treatment shifted LCST to a higher temperature, while the CO2-treatment made the polymer fully water-soluble. The polymer could be readily recovered to its initial state by washing off the trigger gas with an inert gas such as nitrogen. This work provides an effective monomer design approach for the preparation of ...

Acer truncatum seeds are an excellent source of beneficial natural compounds, including high levels of unsaturated fatty acids (UFAs), that promote health. Recently, A. truncatum has emerged as an oil crop. Therefore, the transcriptomes of A. truncatum seeds at 70, 85, 100, 115, 145, 180 days after flowering (DAF) were analyzed to gain a better understanding of the transcriptional and translational regulation of seed development and oil biosynthesis. A total of 28,438 genes were identified, and 3069/2636, 3288/3438, 1319/2750, and 5724/5815 upregulated/downregulated genes were identified when comparing different samples with 85 DAF seeds. Sixteen lipid metabolism pathways with 754 differentially expressed genes (DEGs) were identified, including 34 DEGs associated with UFA biosynthesis. A phylogenetic analysis revealed that six putative fatty acid desaturase (FAD) genes clustered into five FAD groups. A quantitative real-time polymerase chain reaction analysis indicated that the temporal expression patterns of oil biosynthesis genes and transcription factors were largely similar to the RNA sequencing results. The results of this study will enhance the current understanding of oil metabolism in A. truncatum seeds and allow new methods of improving oil quality and seed yield in the future.

Hydrogen sulfide (H2S), a gaseous intracellular signal transducer, participates in multiple physiological and pathological conditions, including reproductive conditions, and disrupts spermatogenesis. The blood-testis barrier (BTB) plays a vital role in spermatogenesis. However, the effect of H2S on the BTB and the underlying mechanism remain unclear. Herein, we examined the effect of H2S and omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on the BTB and testicular functions. ICR male mice were randomly divided into the following groups: control, H2S exposure, and H2S exposure with ω-3 PUFAs intervention. The sperm parameters (sperm concentration and sperm motility) declined in the H2S group and improved in the ω-3 intervention group. BTB integrity was severely disrupted by H2S, and the BTB-related gene levels (ZO-1, Occludin, Claudin 11) decreased; ω-3 supplementation could alleviate BTB disruption by upregulating BTB-related genes, and TM4 Sertoli cells had a similar trend in vitro. p38 MAPK phosphorylation was upregulated in the Na2S treatment group and downregulated after ω-3 cotreatment. These findings suggest that H2S can impair the BTB and that ω-3 PUFAs supplementation can attenuate H2S toxicity in the male reproductive system. Our study elucidated the relationship between a gasotransmitter (H2S) and the BTB and identified the potential therapeutic effect of ω-3 PUFAs.

Poly(ester-b-carbonate)s are successfully synthesized for the first time through the metal-free copolymerization of cyclohexene oxide (CHO), propylene oxide (PO), phthalic anhydride (PA), and CO2 i...

A 3D hierarchical carbon cloth/nitrogen-doped carbon nanowires/Ni@MnO2 (CC/N-CNWs/Ni@MnO2 ) nanocomposite electrode was rationally designed and prepared by electrodeposition. The N-CNWs derived from polypyrrole (PPy) nanowires on the carbon cloth have an open framework structure, which greatly increases the contact area between the electrode and electrolyte and provides short diffusion paths. The incorporation of the Ni layer between the N-CNWs and MnO2 is beneficial for significantly enhancing the electrical conductivity and boosting fast charge transfer as well as improving the charge-collection capacity. Thus, the as-prepared 3D hierarchical CC/N-CNWs/Ni@MnO2 electrode exhibits a higher specific capacitance of 571.4 F g-1 compared with those of CC/N-CNWs@MnO2 (311 F g-1 ), CC/Ni@MnO2 (196.6 F g-1 ), and CC@MnO2 (186.1 F g-1 ) at 1 A g-1 and remarkable rate capability (367.5 F g-1 at 10 A g-1 ). Moreover, asymmetric supercapacitors constructed with CC/N-CNWs/Ni@MnO2 as cathode material and activated carbon as anode material deliver an impressive energy density of 36.4 W h kg-1 at a power density of 900 W kg-1 and a good cycling life (72.8 % capacitance retention after 3500 cycles). This study paves a low-cost and simple way to design a hierarchical nanocomposite electrode with large surface area and superior electrical conductivity, which has wide application prospects in high-performance supercapacitors.

The associated impurity phases derived from the introduction of vanadium ions in yttrium gallium garnet (YGG) were investigated in detail. The XRPD data indicate that β-Ga2O3 is contained in all synthesized samples and YVO4 can be identified when the V-doped concentration above 0.5 at. %. The existence of β-Ga2O3 is related to the antisite defects usually contained in the garnet host, and the generation of YVO4 is mainly derived from its lower formation temperature in comparison to the garnet phase. The micro-area composition analysis further verifies the existence of impurity phases, and the X-ray computed tomography survey provides a more visualized spatial distribution of the YVO4 phase. Moreover, the fluorescence analysis manifests a more sensitive phase identification than the XRPD technique, and the YVO4 impurity phase can be detected even if the V-doped content is reduced to 0.2 at. %. Additionally, the evaluated V/(V + Y + Ga) ratios from structure refinement coincide well with the theoretical value in the low-doping section, and the slight deviation in the high doping part is mainly attributed to the volatilization of vanadium oxides. What discussed in this study offers a comprehensive analysis strategy for the detection of impurity phases originating from ion doping.

Background Starch-based Pickering emulsions have been the focus of considerable research on emulsion-based delivery systems during the past decade. The performance of starch particles at the interface is vital for emulsion stability. The unique gelatinization characteristics and various modifications of starch endow the interface with controllable tuning strategies. However, information regarding the properties of starch-based emulsions from the interface perspective remains limited. Scope and approach This review provides detailed insight into the interfacial properties of starch-based Pickering emulsions. We discuss the interface formation and present the impacts of interfacial properties on the physical stability and gastrointestinal fate of emulsions. Strategies for tuning interfacial behavior are also highlighted. Key findings and conclusions The emulsion interface formation usually involves the complex adsorption behavior of starch particles. Differences in particle shape, roughness, hydrophobicity, and size strongly influence the adsorption stability. The external environment generally affects the destabilization of emulsions by changing the packing density, thickness, mechanical strength, and electrical characteristics of the interface. The protective effect of the starch-based particle laden interface enables the retardation of lipid digestion and drug release. Various methods including the modification of starch particles, co-stabilization with other biopolymers, and pH/ionic strength adjustment are utilized to control interfacial performance and thus improve emulsion properties. The information presented in this review may be used to inform future emulsion studies.