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With the assistance of nickel as catalyst, 2,2'-bipyridine (bpy) as ligand, and manganese as reducing metal, the reductive amidation of isocyanates with readily accessible aryl fluorosulfates could be successfully accomplished. The reactions proceeded effectively via C-O bond activation in DMF at room temperature, enabling the facile synthesis of a range of structurally diverse amides in moderate to high yields with broad functionality compatibility. In addition, the synthetic usefulness of the method was further demonstrated by applying the reaction in scale-up synthesis and the late-stage functionalization of complex molecules with biological activities.

In this study, a nonflammable all-fluorinated electrolyte for lithium-ion cells with a Li(Ni 0.8 Mn 0.1 Co 0.1 )O 2 cathode is investigated under high voltages. This electrolyte, named FT46, consists of fluoroethylene carbonate (FEC) and bis(2,2,2-trifluoroethyl) carbonate (TFEC) in a mass ratio of 4:6. Compared to a commercially available electrolyte and several other fluorinated electrolytes, cells containing FT46 demonstrate significantly better cycling performances under high voltage (3.0-4.5 V). This result may be ascribed to the generation of a stable, smooth, and thin passivation layer and the improved solvation structure formed by FT46. The LiF-rich passivation layer strengthens the electrode/electrolyte interface, inhibits the degradation of the electrode, and suppresses side reactions between the electrodes and electrolytes under high voltage. The solvation structure formed by FT46 is derived from anions, enabling an enhanced Li + migration rate and inhibiting lithium plating generation. Additionally, due to the nonflammability of the electrolyte and the stable passivation layers, FT46 cells also demonstrate promising safety characteristics when exposed to typical abusive conditions, such as thermal abuse, mechanical abuse, and electrical abuse.

We developed a simple strategy for preparing IrSn bimetallic clusters encapsulated in pure silicon zeolites via a one-pot hydrothermal synthesis by using diethylamine as a stabilizing agent. A series of investigations verified that metal species have been confined successfully in the inner of MFI zeolites. IrSn bimetallic cluster catalysts were efficient for the CO selective catalytic reduction of NO x in the presence of excess O 2 . Furthermore, the 13 CO temperature-programmed surface reaction results demonstrated that NO 2 and N 2 O could form when most of the CO was transformed into CO 2 and that Sn modification could passivate CO oxidation on the IrSn bimetallic clusters, leading to more reductants that could be used for NO x reduction at high temperatures. Furthermore, SO 2 can also influence the NO x conversion by inhibiting the oxidation of CO. This study provides a new strategy for preparing efficient environmental catalysts with a high dispersion of metal species.

Aerogel fibers are good thermal insulators, suitable for weaving, and show potential as the next generation of intelligent textiles that can effectively reduce heat consumption for personal thermal management. However, the production of continuous aerogel fibers from biomass with sufficient strength and radial elasticity remains a significant challenge. Herein, continuous gel fibers were produced via wet spinning using agarose (AG) as the matrix, 2,2,2,6,6-tetramethylpiperidine-1-oxyl radical-oxidized cellulose nanofibers (TOCNs) as the reinforcing agent, and no other chemical additives by utilizing the gelling properties of AG. Supercritical drying and chemical vapor deposition (CVD) were then used to produce hydrophobic AG-TOCN aerogel fibers (HATAFs). During CVD, the HATAF gel skeleton was covered with an isostructural silica coating. Consequently, the HATAFs can recover from radial compression under 60% strain. Moreover, the HATAFs have low densities (≤0.14 g cm -3 ), high porosities (≥91.8%), high specific surface areas (≥188 m 2 g -1 ), moderate tensile strengths (≤1.75 MPa), excellent hydrophobicity (water contact angles of >130°), and good thermal insulating properties at different temperatures. Thus, HATAFs are expected to become a new generation of materials for efficient personal thermal management.

Deoxynivalenol (DON) poses a serious global food safety risk due to its high toxicity and contamination rate. It disrupts the intestinal epithelial barrier, allowing exogenous toxins to enter the circulation and resulting in sepsis and systemic toxicity. In this research, 32 male Kunming mice and Porcine Small Intestinal Epithelial (IPEC-J2) cells were treated with DON at 0-4.8 mg/kg (7 d) and 0-12 μM (24 h), respectively. Histopathological results revealed that DON disrupted the intestinal epithelial barrier, causing apoptosis and tight junction (TJ) injury. Immunofluorescence and protein expression results showed that DON-induced p53-dependent mitochondrial pathway apoptosis and fibrillar actin (F-actin)-associated TJ injury and that the RhoA/ROCK pathway were activated in mice jejunal tissue and IPEC-J2 cells. Pretreatment with RhoA or ROCK inhibitors (Rosin or Y-27632) maintained DON-induced apoptosis and F-actin-associated TJ injury in IPEC-J2 cells. Thus, DON induces damage to the intestinal epithelial barrier through the RhoA/ROCK pathway-mediated apoptosis and F-actin-associated TJ disruption.

The worldwide prevalence of Aflatoxin B1 (AFB 1 ), which contaminates feedstock and food, is on the rise. AFB 1 inhibits testosterone (T) biosynthesis, but the mechanism is not yet clear. By establishing in vivo and in vitro models, this study found the number of Leydig cells (LCs), T content, and the expression of T biosynthesis key enzymes were suppressed after AFB 1 treatment. AFB 1 exposure also increased reactive oxygen species (ROS) and promoted mitochondrial injury and mitochondrial pathway apoptosis. Moreover, the AMPK signaling pathway was activated, and using an AMPK inhibitor relieved apoptosis and the suppressed T biosynthesis key enzymes of LCs caused by AFB 1 through regulating downstream p53 and Nur77. Additionally, adding ROS intervention could inhibit AMPK activation and alleviate the decreased T content caused by AFB 1 . In summary, AFB 1 promotes the apoptosis of LCs and inhibits T biosynthesis key enzyme expression via activating the ROS/AMPK signaling pathway, which eventually leads to T synthesis disorder.

We successfully achieved the phosphorylation of secondary aromatic alcohols with H-phosphine oxides (less developed system) using phosphotungstic acid as a catalyst in dimethyl carbonate. The system was simple and environmentally friendly and showed better activity than traditional Lewis or Brønsted acids such as FeCl 3 , p -TsOH·H 2 O, etc., generating up to a 97% isolated yield. Control experiments indicated that the reaction did not occur through the radical pathway, and ethers and carbocation were the key intermediates in the pathway.

Designing flexible wearable sensors with a wide sensing range, high sensitivity, and high stability is a vulnerable research direction with a futuristic field to study. In this paper, Ti 3 C 2 T x MXene/carbon nanotube (CNT)/thermoplastic polyurethane (TPU)/polysulfone (PSF) composite films with excellent sensor performance were obtained by self-assembly of conductive fillers in TPU/PSF porous films with an asymmetric structure through vacuum filtration, and the porous films were prepared by the phase inversion method. The composite films consist of the upper part with finger-like "cavities" filled by MXene/CNTs, which reduces the microcracks in the conductive network during the tensile process, and the lower part has smaller apertures of a relatively dense resin cortex assisting the recovery process. The exclusive layer structure of the MXene/CNTs/TPU/PSF film sensor, with a thickness of 46.95 μm, contains 0.0339 mg/cm 2 single-walled carbon nanotubes (SWNTs) and 0.348 mg/cm 2 MXene only, providing functional range (0-80.7%), high sensitivity (up to 1265.18), and excellent stability and durability (stable sensing under 2300 fatigue tests, viable to the initial resistance), endurably cycled under large strains with serious damage to the conductive network. Finally, the MXene/CNTs/TPU/PSF film sensor is usable for monitoring pulse, swallow, tiptoe, and various joint bends in real time and distributing effective electrical signals. This paper implies that the MXene/CNTs/TPU/PSF film sensor has broad prospects in pragmatic applications.

Colorectal cancer is one of the most common malignant tumors. At the advanced stage of colorectal cancer, cancer cells migrate with the blood to the liver from the hepatic portal vein, eventually resulting in a portal vein tumor thrombus (PVTT). To date, the progression of the early onset of PVTT [portal vein microthrombus (PVmT) induced by tumors] is unclear. Herein, we developed an on-chip PVmT model by loading the spheroid of colorectal cancer cells into the portal vein of a hepatic lobule chip (HLC). On the HLC, the progression of PVmT was presented, and early changes in metabolites of hepatic cells and in structures of hepatic plates and sinusoids induced by PVmT were analyzed. We replicated intrahepatic angiogenesis, thickened blood vessels, an increased number of hepatocytes, disordered hepatic plates, and decreased concentrations of biomarkers of hepatic cell functions in PVmT progression on a microfluidic chip for the first time. In addition, the combined therapy of thermo-ablation and chemo-drug for PVmT was preliminarily demonstrated. This study provides a promising method for understanding PVTT evolution and offers a valuable reference for PVTT therapy.

The current methods of constructing modification strategies for hydrophilic membranes are time-consuming, complex in operation, and poor in universality, which limit their application on membranes. In this work, inspired by the adhesion properties and versatility of caffeic acid (CA) and p -phenylenediamine (PPDA), a simple, rapid, and universal method was designed for the separation of oil-in-water emulsion by preparing a stable hydrophilic coating separation membrane. The preparation time of the membrane was shortened to 40 min. The developed PVDF-PCA/PPDA membrane showed superhydrophilic and underwater superoleophobic properties. When applied to petroleum ether-in-water emulsion, isooctane-in-water emulsion, and dodecane-in-water emulsion separation, the oil rejection was more than 99.0%. In the circulating separation of 10 g/L soybean oil-in-water emulsion, the oil rejection was more than 99.3%, and the highest flux was 1036 L·m -2 ·h -1 . The prepared PVDF-PCA/PPDA membrane performed well in the separation test of oily wastewater. The proposed strategy is simple and rapid; it may become a universal method for preparing membranes with super strong antifouling properties against viscous oil and accelerate the research progress of membrane separation of oil-in-water emulsions.

For protecting the exquisite structural patterns of such coins, developments of simple preparation methods were explored to achieve good hydrophobic capability and the wear-damage resistance of CuZnPb surfaces. A self-cleaning nanoliquid (SN) was combined with microstructured Ag-dispersed CuZnPb (MAC) to realize good hydrophobicity functions of the SNMAC. This was because the cooperative functions of silver and the SN enhanced the water reunion ability and increased solid-liquid-gas contact areas, leading to high contact angles of SNMAC. Their cooperations produced discrepant forces in their respective areas of the water drops and increased heterogeneous flowing, resulting in a high-angle hysteresis of SNMAC. Subsequently, the wear-damage resistance of the hydrophobic interface was measured in a ball-on-flat tribopair system, and the results showed that sliding injuries made a height distribution of the hydrophobic surface trend toward an equalization, allowing the cooperation of nano-silver, SN, and CuZnPb to form a new-style interface for achieving excellent hydrophobicity, thus producing the highest contact angles of the SNMAC among the as-prepared samples.

With the emergence of various cutting-edge micromachining technologies, lab on a chip is growing rapidly, but it is always a challenge to realize the on-chip separation of living cells from cell samples without affecting cell activity and function. Herein, we report a novel on-chip label-free method for sorting living and dead cells by integrating the hypertonic stimulus and tilted-angle standing surface acoustic wave (T-SSAW) technologies. On a self-designed microfluidic chip, the hypertonic stimulus is used to distinguish cells by producing volume differences between living and dead cells, while T-SSAW is used to separate living and dead cells according to the cell volume difference. Under the optimized operation conditions, for the sample containing 50% of living human umbilical vein endothelial cells (HUVECs) and 50% of dead HUVECs treated with paraformaldehyde, the purity of living cells after the first separation can reach approximately 80%, while after the second separation, it can be as high as 93%; furthermore, the purity of living cells after separation increases with the initial proportion of living cells. In addition, the chip we designed is safe for cells and can robustly handle cell samples with different cell types or different causes of cell death. This work provides a new design of a microfluidic chip for label-free sorting of living and dead cells, greatly promoting the multi-functionality of lab on a chip.

Deoxynivalenol (DON) is widely present in cereals and processed grains. It can disrupt the blood-testicular barrier (BTB), leading to sterility in males; however, the mechanism is unknown. In this study, 30 Kunming mice and TM4 cells were exposed to 0 or 4.8 mg/kg (28 d) and 0-2.4 μM (24 h) of DON, respectively. Histopathological findings showed that DON increased BTB permeability in mice, leading to tight junction (TJ) structural damage. Immunofluorescence results indicated that DON disrupted the localization of zonula occludens (ZO)-1. The results of protein and mRNA expression showed that the expression of ZO-1, occludin, and claudin-11 was reduced, and that the p38/GSK-3β/snail and p38/ATF-2/MLCK signaling pathways were activated in mouse testes and TM4 cells. Pretreatment with the p38 inhibitor SB203580 maintained TJ integrity in TM4 cells after exposure to DON. Thus, DON induced BTB dysfunction in mice by disrupting p38 pathway-mediated TJ expression and distribution.

A nickel-catalyzed direct cross-coupling of unactivated aryl fluorides with aryl bromides is realized. The one-pot reaction, which avoids the use of preformed and sensitive organometallic reagents, proceeds effectively via C-F bond cleavage at room temperature in THF in the presence of the phosphine ligand and magnesium powder (with or without TMSCl) to produce the desired biaryls in modest to good yields.

Low power and high switching ratio are the development direction of the next generation of resistive random access memory (RRAM). Previous techniques could not increase the switching ratio while reducing the SET power. Here, we report a method to fabricate low-power and high-switching-ratio RRAM by adjusting the interstice radius ( r g ) between the van der Waals (vdW) layers of transitional-metal dichalcogenides (TMDs), which simultaneously increases the switching ratio and reduces the SET power. The SET voltage, SET power, switching ratio and endurance of the device are strongly correlated with r g . When the ratio of r g to the radius of the metal ions that form the conductive filaments ( r g / r Ag + ) is near 1, the SET voltage and SET power vertically decrease while the switching ratio vertically rises with increasing r g / r Ag + . For the fabricated Ag/[SnS 2 /poly(methyl methacrylate)]/Cu RRAM with an r g / r Ag + of 1.04, the SET voltage, SET power and switching ratio are 0.14 V, 10 -10 W and 10 6 , respectively. After 10 4 switching cycles and a 10 4 s retention time, the switching ratio of the device can still be stable above 10 6 . Bending has no influence on the performance of the device when the bending radius is not <2 mm.

Due to thrombosis and intimal hyperplasia, small-diameter vascular grafts have poor long-term patency. A combination strategy based on nitric oxide (NO) and anticoagulants has the potential to address those issues. In this study, poly(ethylene terephthalate) (PET) mats were prepared by electrospinning and coated with tannic acid (TA)/copper ion complexes. The chelated copper ions endowed the mats with sustained NO generation by catalytic decomposition of endogenous S-nitrosothiol. Subsequently, zwitterionic carboxybetaine acrylate (CBA) and argatroban (AG) were immobilized on the mats. The introduced AG and CBA had synergistic effects on the improvement of blood compatibility, resulting in reduced platelet adhesion and prolonged blood clotting time. The biocomposite mats selectively promoted the proliferation and migration of human umbilical vein endothelial cells while inhibiting the proliferation and migration of human umbilical arterial smooth muscle cells under physiological conditions. In addition, the prepared mats exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus . Collectively, the prepared mats hold great promise as artificial small-diameter vascular grafts.

Patients suffering diabetic bone defects still need some new and effective strategies to achieve enhanced prognostic effects. Although medical implants are the common treatment of bone defects, the excessive oxidative stress and high risk of bacterial infection in diabetes mellitus lead to a higher risk of implant failure. To improve the healing ability of diabetic bone defects, herein, polyetheretherketone (PEEK) was modified through a developed layer-by-layer (LBL) construction strategy to obtain multifunctional PEEK (SP@(TA-GS/PF)*3) by the assembly of tannic acid (TA), gentamicin sulfate (GS) and Pluronic F127 (PF127) on the basis of prepared porous PEEK through sulfonation (SPEEK). The prepared SP@(TA-GS/PF)*3 exhibited sustained antimicrobial activity and enhanced the differentiation of osteoblast (MC3T3-E1) for needed osteogenesis. Moreover, SP@(TA-GS/PF)*3 scavenged excessive oxidative stress to promote the growth of H 2 O 2 damaged HUVEC with enhanced secretion of VEGF for neovascularization. In addition, the remarkable in vivo outcomes of angiogenesis and osseointegration were revealed by the subcutaneous implant model and bone tissue implant model in diabetic rats, respectively. The in vitro and in vivo results demonstrated that modified PEEK with multifunction can be an attractive tool for enhancing bone integration under diabetic conditions, underpinning the clinical application potential of modified implants for diabetic osseointegration.

Plant polyphenol-inspired surface modification of membranes is helpful for oil-water separation. However, the preparation of this coating is time-consuming. Herein, we introduce a rapid synthesis of the TA-APTES coating by the addition of sodium periodate (SP). The surface chemical composition and morphology of the resultant TA-APTES hybrid coatings were characterized using SEM, ATR-FTIR, and XPS. The hydrophilicity and membrane performance were investigated by the water contact angle, pure water permeability, and oil rejection for an isooctane-in-water emulsion. The experimental findings revealed that the optimal microfiltration (MF) membrane (MF-TA-APTES-SP-0.05) displayed exceptional hydrophilicity and water permeability (9558 L m -2 h -1 bar -1 ). The membrane realized highly efficient separation with a permeability (4117 L m -2 h -1 bar -1 ) and rejection of oils (>99%). Furthermore, it possessed outstanding chemical stability and maintained underwater superoleophobicity even after exposure to harsh conditions. This simple and rapid strategy of developing hydrophilic coatings as a modifier for the poly(vinylidene fluoride) membranes has potential applications in oil-water separation and wastewater treatment.

The dry reforming of methane (DRM) is a new potential technology that converts two major greenhouse gases into useful chemical feedstocks. The main challenge faced by this process is maintaining the catalyst with high catalytic activity and long-term stability. Here, a simple and effective preparation route for the synthesis of functional nanomolecular sieve catalysts (NiRu x CZZ5) from kaolinite tailings was developed for dry reforming of methane with CO 2 . The silica monoliths with flower-like spherical and micropore structures (ZSM-5) were prepared by crystal growth method, and the metal components were loaded by ultrasonic-assisted impregnation method. The NiRu 0.5 CZZ5 catalyst exhibited excellent catalytic performance (maxmium CO 2 and CH 4 conversions up to 100 and 95.6%, respectively) and very good stability (up to 100h). The interfacial confinement and the strong support interaction are principally responsible for the excellent catalytic activity of the catalyst. The in situ DRIFTS was used to elucidate the possible carbon conversion steps, and stable surface intermediates were also identified.

Pyrano[3,2- c ]coumarin derivatives and C3-substituted 4-hydroxycoumarins as important skeletal structures of active natural products and pharmaceutically relevant molecules have received increasing attention. However, developing an adjustable system for selectively synthesizing them is still a challenging task. Herein, sulfonic acid-functionalized ionic liquid was successfully used as the catalyst for the alkylation of 4-hydroxycoumarin derivatives with secondary aromatic propargylic alcohols using dimethyl carbonate as the green solvent, giving up to 98% yield. On the other hand, protonated imidazole-based ionic liquid-catalyzed cyclization was also selectively achieved with a nearly quantitative yield. Developed metal-free catalytic systems exhibited well adjustable and recyclable properties, avoiding the contamination of metal and halogen, reducing the neutralization after the reaction, and benefiting the separation between the catalyst and the product. New strategies were applied for performing the gram-scale reaction smoothly. The adjustable systems might occur through two different mechanisms involving propargylic or allenic carbocation and hydrogen bonding effects between the catalysts and the substrates.

Lithium-sulfur (Li-S) batteries are considered a prospective energy storage system because of their high theoretical specific capacity and high energy density, whereas Li-S batteries still face many serious challenges on the road to commercialization, including the shuttle effect of lithium polysulfides (LiPSs), their insulating nature, the volume change of the active materials during the charge-discharge process, and the tardy sulfur redox kinetics. In this work, double transition metal oxide TiNb 2 O 7 (TNO) nanometer particles are tactfully deposited on the surface of an activated carbon cloth (ACC), activating the surface through a hydrothermal reaction and high-temperature calcination and finally forming the flexible self-supporting architecture as an effective catalyst for sulfur conversion reaction. It has been found that ACC@TNO possesses many catalytic activity sites, which can inhibit the shuttle effect of LiPSs and increase the Coulombic efficiency by boosting the redox reaction kinetics of LiPS transformation reaction. As a consequence, the ACC@TNO/S cathode exhibits an impressive electrochemical performance, including a high initial discharge capacity of 885 mAh g -1 at a high rate of 1 C, a high discharge specific capacity of 825 mAh g -1 after 200 cycles with a prominent capacity retention rate of 93%, and a small decay rate of 0.034% per cycle. Although TNO is extensively used in the fields of lithium ion batteries and other rechargeable batteries, it is first introduced as sulfur host materials to boost the redox reaction kinetics of the LiPS transformation reaction and increase the electrochemical performance of Li-S batteries. Therefore, studies of the synergistic effect on the chemical absorption and catalytic conversion effect of TNO for LiPSs of Li-S batteries provide a good strategy for boosting further the comprehensive electrochemical performances of Li-S batteries.

Hydrogel-based electronics have received growing attention because of their great flexibility and stretchability. However, the fabrication of conductive hydrogels with high stretchability, excellent toughness, outstanding sensitivity, and low-temperature stability still remains a great challenge. In this study, a type of conductive hydrogels consisting of a double network (DN) structure is synthesized. The dynamically cross-linked chitosan (CS) and the flexible polyacrylamide network doped with polyaniline constitute the DN through the hydrogen bonds between the hydroxyl, amide, and aniline groups. This type of hydrogels displays excellent mechanical performance, striking conductivity, and remarkable freezing tolerance. The flexible electronic sensors based on the double-network hydrogels demonstrate superior strain sensitivity and linear response on various deformations. Additionally, the good antifreezing property of the hydrogels allows the sensors to exhibit excellent performance at -20 °C.

In this work, we synthesized a series of Cu/ZrO 2 catalysts with tunable V o -Cu 0 (oxygen vacancy adjacent to Cu metal) and V Zr -Cu δ+ (zirconium vacancy adjacent to electron-deficient Cu species) dual-interface sites and investigated the role of the dual-interface sites in the 5-hydroxymethylfurfural (5-HMF) hydrogenolysis reaction with isopropanol as the hydrogen source. By combining a series of in situ infrared characterization and catalytic performance analysis, it is identified that V o -Cu 0 interface sites were responsible for activating isopropanol dehydrogenation and C═O dissociation of 5-HMF, while the V Zr -Cu δ+ interface sites were responsible for the dehydroxylation of an intermediate product 5-methyl-2-furfuryl alcohol (5-MFA). Specifically, C-OH was first deprotonated on the V Zr at the V Zr -Cu δ+ interface site to reduce the activation energy of 5-MFA dehydroxylation and then adjacent Cu δ+ promoted the dissociation of the C-O bond by enhancing the adsorption energy while elongating the C-O bond, as confirmed by the density functional theory calculations. Because the dual-interface sites provided separate sites for activating intermediate products and reactants, the coupling reaction caused by competitive adsorption is thus well avoided. Therefore, the optimized Cu/ZrO 2 catalyst with the most V Zr -Cu δ+ and moderate V o -Cu 0 sites exhibited 98.4% of 2,5-dimethylfuran yield under the conditions of 180 °C and self-vapor pressure.

The tail spike of the mantis shrimp is the appendage for counteracting the enemy from behind. Here, we investigate the correlations between the chemical compositions, the microstructures, and the mechanical properties of the spike. We find that the spike is a hollow beam with a varying cross section along the length. The cross section comprises four different layers with distinct features of microstructures and chemical compositions. The local mechanical properties of these layers correlate well with the microstructures and chemical compositions, a combination of which effectively restricts the crack propagation while maximizing the release of strain energy during deformation. Finite element analysis and mechanics modeling demonstrate that the optimized structure of the spike confines the mechanical damage in the region near the tip and prevents catastrophic breakage at the base. Furthermore, we use a 3D printing technique to fabricate multiple hollow cylindrical samples consisting of biomimetic microstructures of the spike and confirm that the combination of the Bouligand structure with radially oriented parallel sheets greatly improves the toughness and strength during compression tests. The multiscale design strategy of the spike revealed here is expected to be of great interest for the development of novel bioinspired materials.

The negative photoconductivity (NPC) effect originating from the surface shell layer has been considered as an efficient approach to improve the performance of optoelectronic nanodevices. However, a scientific design and precise growth of NPC-effect-caused shell during nanowire (NW) growth process for achieving high-performance photodetectors are still lacking. In this work, GeS NWs with a controlled sulfur-rich shell, diameter, and length are successfully prepared by a simple chemical vapor deposition method. As checked by transmission electron microscopy, the thickness of the sulfur-rich shell ranges from 10.5 ± 1.5 to 13.4 ± 2.5 nm by controlling the NW growth time. The composition of the sulfur-rich shell is studied by X-ray photoelectron spectroscopy, showing the decrease of S in the GeS x shell from the surface to core. When configured into the well-known phototransistor, a featured NPC effect is observed, benefiting the high-performance photodetector with high responsivity of 10 5 A·W -1 and detectivity of 10 12 Jones for λ = 405 nm with ultralow intensity of 0.04 mW·cm -2 . However, the thicker-shell NW phototransistor shows an unstable photodetector behavior with smaller negative photocurrent because of more hole-trapping states in the thicker shell. All results suggest a careful design and controlled growth of an NPC-effect-caused shell for future optoelectronic applications.

Because of the inherent quasibrittleness and heterogeneity, matrix-directed toughening of concrete and cement composites remains to be a huge challenge. Herein, inspired by nacre materials, a novel biomimetic bulk cement composite is fabricated via a facile and efficient process based on compacting prefabricated multisized cement-polymer hybrid prills. This method combines with the three-dimensional "brick-bridge-mortar" structure design and synchronously the intrinsic and extrinsic toughening strategies. Such an approach shows the remarkable maximum toughness enhancement of 27-fold with 71% increase in flexural strength via cooperation with only 4 wt % organic matter. More attractively, it alters the traditional brittle fracture of cement composites to a distinct ductile fracture. In addition, such a biomimetic composite demonstrates the long-term ever-increasing strength and toughness, performing the excellent ductile-fracture retention ability. The hierarchical toughening mechanisms are further revealed with the synergy of microscopic characterizations and simulation methods. This strategy provides a new route for the development of high toughness biomimetic cement-based materials for potential applications in civil engineering domain.

Cylindrospermopsin (CYN) is one of the most important cyanobacterial toxins frequently found in surface waters. We reported the detailed kinetics and pathways for the reaction of CYN with carbonate radicals (CO 3 •- ). The rate constants of neutral and deprotonated CYN with CO 3 •- were found to be (1.2 ± 0.7) × 10 7 M -1 s -1 and (3.0 ± 0.4) × 10 8 M -1 s -1 , respectively. The transformation products for the oxidation of CYN by CO 3 •- were identified by high-resolution mass spectrometry, illustrating that the guanidine and bridged hydroxyl portions were the primary moieties attacked by CO 3 •- . Thus, three transformation pathways, including cleavage of the hydroxymethyluracil moiety, hydroxylation, and oxidation of the bridged hydroxyl group, are proposed for the CO 3 •- oxidation of CYN. Moreover, this study reported that dissolved organic matter (DOM) reduced the transformation rate of CYN by inhibiting the transformation of oxidation intermediates. Finally, the role of CO 3 •- in CYN degradation was estimated in both sunlit surface waters and advanced oxidation processes (AOPs), demonstrating that CO 3 •- played an important role in CYN attenuation under nonacidic environmentally relevant conditions. The kinetic parameters and product information obtained in this study will be of considerable interest for the application of AOPs and predicting the environmental fate of CYN.

The increased demand for electronic devices, combined with a desire to minimize the environmental impact, necessitates the development of new eco-friendly materials. One promising approach is the incorporation of renewable and green materials that possess the desired mechanical and electrical properties while allowing for more ecologically friendly disposal of these devices. The addition of low-weight percentages (0.25-0.75 wt %) of cellulose nanocrystals (CNCs) was investigated as an environmentally friendly additive in aqueous dispersions of poly(vinyl alcohol) (PVA). It was found that these low CNC loadings were sufficient to induce a favorable increase in viscosity, which in turn dramatically enhanced the film quality of the PVA blends through an improvement in the critical radius of the spun film, overall film thickness, and homogeneity of the thin film. This corresponded to an increase in the number of functioning organic electronic devices that could be fabricated by spin coating, including metal-insulator-metal (MIM) capacitors and organic thin-film transistors (OTFTs). Most importantly, the incorporation of CNCs into PVA did not significantly alter the native dielectric properties of the polymer thin films when incorporated into both MIM capacitors and OTFTs.

Metal-organic framework (MOF)-derived composites of transition metal oxides and porous carbon show great potential for energy storage applications. Selenylation is an effective strategy to improve the electrochemical properties of electrode materials. A facile one-step derivation and selenylation of MOFs is proposed here to obtain CoSe 2 nanoparticles embedded into an N-doped carbon skeleton material (CoSe 2 /NC). Moreover, the composite is directly grown on nickel foam as nanosheet arrays, rather than on other materials as powders. The CoSe 2 /NC electrode with special construction exhibits a high capacity of 120.2 mA h g -1 at 1 A g -1 and an excellent cyclic ability of 8% loss after 10,000 cycles. An asymmetric supercapacitor CoSe 2 /NC-NF//AC displays a maximum energy density of 40.9 W h kg -1 at 980 W kg -1 . Moreover, the device has demonstrated that it can successfully charge a mobile phone. The outstanding performance indicates promising potential of CoSe 2 /NC-NF electrodes for supercapacitors.

A novel tetrabutylammonium iodide (TBAI)-promoted three-component reaction of carboxylic acid with alkene and alcohol has been developed, which represents facile and straightforward access to polysubstituted γ-lactone skeletons in moderate-to-good yields. This methodology is distinguished by the use of a commercial catalyst and readily available starting materials, wide substrate scope, and operational simplicity. Mechanistic studies suggested that this transformation went through a radical process.

Li-S battery has tremendous application prospect on account of the high theoretical specific capacity and large energy density, while its large-scale application is impeded by the severe shuttle effect and the slow electrochemical kinetics of polysulfides conversion. Herein, the Lewis acidic yttria hollow spheres (YHS) are rationally designed as both sulfur immobilizer and catalyst of polysulfides conversion for the advanced Li-S batteries. It can be known that the Lewis acidic yttria can effectively capture the Lewis basic polysulfides and thus mitigate the shuttle effect of Li-S battery; besides, yttria shows the enhanced catalytic effect for the kinetics of interconversion reaction from polysulfides to Li 2 S. As a result, either as a sulfur host or as the separator coating, yttria plays a vital part in realizing the high specific discharge capacity and good cycle stability for Li-S battery. In particular, Li-S battery with YHS@C/S cathode and YHS/CNT-0.6- modified separator (2.1 mg cm -2 active material loading) shows a good specific discharge capacity of 912.5 mAh g -1 at 0.5C. Even after 200 steady cycles, the discharge specific capacity can keep as 842.3 mAh g -1 , and the capacity decay rate is only 0.038% per cycle. When active material areal loading is increased to 4.24 mg cm -2 , it still maintains a considerable areal capacity of 3.79 mAh cm -2 . In consequence, the synergy of polysulfides confinement and catalytic conversion reaction provides a meaningful exploration for achieving the high performance of Li-S batteries.

Owing to the relatively low hole mobility, the development of GaSb nanowire (NW) electronic and photoelectronic devices has stagnated in the past decade. During a typical catalyst-assisted chemical vapor deposition (CVD) process, the adopted metallic catalyst can be incorporated into the NW body to act as a slight dopant, thus regulating the electrical properties of the NW. In this work, we demonstrate the use of Sn as a catalyst and dopant for GaSb NWs in the surfactant-assisted CVD growth process. The Sn-catalyzed zinc-blende GaSb NWs are thin, long, and straight with good crystallinity, resulting in a record peak hole mobility of 1028 cm 2 V -1 s -1 . This high mobility is attributed to the slight doping of Sn atoms from the catalyst tip into the NW body, which is verified by the red-shifted photoluminescence peak of Sn-catalyzed GaSb NWs (0.69 eV) compared with that of Au-catalyzed NWs (0.74 eV). Furthermore, the parallel array NWs also show a high peak hole mobility of 170 cm 2 V -1 s -1 , a high responsivity of 61 A W -1 , and fast rise and decay times of 195.1 and 380.4 μs, respectively, under the illumination of 1550 nm infrared light. All of the results demonstrate that the as-prepared Sn-catalyzed GaSb NWs are promising for application in next-generation electronics and optoelectronics.

The dimerization and high-order oligomerization of transcription factors has endowed them with cooperative regulatory capabilities that play important roles in many cellular functions. However, such advanced regulatory capabilities have not been fully exploited in synthetic biology and genetic engineering. Here, we engineered a C-terminally fused oligomerization domain to improve the cooperativity of transcription factors. First, we found that two of three designed oligomerization domains significantly increased the cooperativity and ultrasensitivity of a transcription factor for the regulated promoter. Then, seven additional transcription factors were used to assess the modularity of the oligomerization domains, and their ultrasensitivity was generally improved, as assessed by their Hill coefficients. Moreover, we also demonstrated that the allosteric capability of the ligand-responsive domain remained intact when fusing with the designed oligomerization domain. As an example application, we showed that the engineered ultrasensitive transcription factor could be used to significantly improve the performance of a "stripe-forming" gene circuit. We envision that the oligomerization modules engineered in this study could act as a powerful tool to rapidly tune the underlying response profiles of synthetic gene circuits and metabolic pathway controllers.

Despite rapid progresses in single-cell analysis technologies, efforts to control the three-dimensional microenvironment for single cell measurements have been lacking. Here, we report a simple method to incorporate three-dimensional scaffolds, including polyvinylidene fluoride (PVDF) membranes and PVDF membrane replicated analog polydimethylsiloxane, into multiplexed single cell secretomic analysis platforms (including a microwell array and a single cell barcode microchip) to mimic the extracellular physical matrix and mechanical support for single cells. Applying this platform to brain tumor cell line U87 to investigate single cell protein secretion behavior on different substrates, we revealed that single cell protein secretions were regulated differently in three-dimensional (3D) microenvironments. This finding was further verified with intracellular cytokine staining, highlighting the significance of 3D single cell microenvironments. This new single cell biomimetic platform can be easily adaptable to other three-dimensional cell culture scaffolds or other single cell assays and may become a broadly applicable three-dimensional single cell analysis system to study the effect of microenvironment conditions on cellular functional heterogeneity in vitro.

Novel dual nicotinamide phosphoribosyltransferase (NAMPT) and histone deacetylase (HDAC) inhibitors were designed by a pharmacophore fusion approach. The thiazolocarboxamide inhibitors were highly active for both targets. In particular, compound 7f (NAMPT IC 50 = 15 nM, HDAC1 IC 50 = 2 nM) showed potent in vivo antitumor efficacy in the HCT116 xenograft model. The study offers a new strategy for multitarget antitumor drug discovery by simultaneously acting on cancer metabolism and epigenetics., Competing Interests: The authors declare no competing financial interest.

Cancer metabolism and epigenetics are among the most intensely pursued research areas in anticancer drug discovery. Here we report the first small molecules that simultaneously inhibit nicotinamide phosphoribosyltransferase (NAMPT) and histone deacetylase (HDAC), two important targets of cancer metabolism and epigenetics, respectively. Through iterative structure-based drug design, chemical synthesis, and biological assays, a highly potent dual NAMPT and HDAC inhibitor was successfully identified. Compound 35 possessed excellent and balanced activities against both NAMPT (IC 50 = 31 nM) and HDAC1 (IC 50 = 55 nM). It could effectively induce cell apoptosis and autophagy and ultimately led to cell death. Importantly, compound 35 showed excellent in vivo antitumor efficacy in the HCT116 xenograft model. This proof-of-concept study demonstrates the feasibility of discovering an inhibitor targeting cancer metabolism and epigenetics and provides an efficient strategy for multitarget antitumor drug discovery.

Cellular mechanosensing is critical for many biological processes, including cell differentiation, proliferation, migration, and tissue morphogenesis. The actin cytoskeletal proteins play important roles in cellular mechanosensing. Many techniques have been used to investigate the mechanosensory behaviors of these proteins. However, a fast, low-cost assay for the quantitative characterization of these proteins is still lacking. Here, we demonstrate that compression assay using agarose overlay is suitable for the high throughput screening of mechanosensory proteins in live cells while requiring minimal experimental setup. We used several well-studied myosin II mutants to assess the compression assay. On the basis of elasticity theories, we simulated the mechanosensory accumulation of myosin II's and quantitatively reproduced the experimentally observed protein dynamics. Combining the compression assay with confocal microscopy, we monitored the polarization of myosin II oligomers at the subcellular level. The polarization was dependent on the ratio of the two principal strains of the cellular deformations. Finally, we demonstrated that this technique could be used on the investigation of other mechanosensory proteins.

A metal-free and efficient approach to N-aryl-substituted azacycles from arylamines and cyclic ethers is described. In this synthesis, the synergistic effect between Lewis and Brønsted acids is crucial to the ring-opening of cyclic ethers and the subsequent cyclization. The use of B(C6F5)3 enabled the formation of frustrated Lewis pairs (FLPs) from the reactants, and the resulting FLPs allowed ready access to the N-arylazacycles in moderate to good yields via further cyclization. Water is the sole waste resulting from the reaction, thereby making it an environmentally benign process.

A novel family of bioinspired manganese(II) complexes bearing chiral aminopyridine ligands that possessed additional aromatic groups and strong donating dimethylamino groups were synthesized and characterized. These manganese complexes exhibited efficient and improved activities in the asymmetric epoxidation of various olefins, such as styrene derivatives (up to 93% ee) with H2O2 as the oxidant, even with a catalytic amount of carboxylic acid as the additive.

We report a remarkable Brønsted acid effect in the epoxidation of olefins by nonheme manganese catalysts and aqueous hydrogen peroxide. More specifically, a mononuclear nonheme manganese complex bearing a tetradentate N4 ligand, Mn(II)(Dbp-MCP)(OTf)2 (Dbp-MCP = (1R,2R)-N,N'-dimethyl-N,N'-bis((R)-(3,5-di-tert-butyl-phenyl)-2-pyridinylmethyl)cyclohexane-1,2-diamine; OTf(-) = CF3SO3(-)), is a highly efficient catalyst in the epoxidation of olefins by aqueous H2O2 in the presence of H2SO4 (1-3 mol %). The yields of epoxide products as well as the chemo- and enantioselectivities increase dramatically in the presence of H2SO4; no formation of epoxides is observed in the absence of H2SO4. In addition, the product yields and enantioselectivities are dependent significantly on the manganese catalysts and Brønsted acids. The catalytic epoxidation of olefins by other oxidants, such as peracids, alkyl hydroperoxides, and iodosylbenzene, is also affected by the presence of H2SO4; product yields and enantioselectivities are high and similar irrespective of the oxidants in the presence of H2SO4, suggesting that a common epoxidizing intermediate is generated in the reactions of [Mn(II)(Dbp-MCP)](2+) and the oxidants. Mechanistic studies, performed with (18)O-labeled water (H2(18)O) and cumyl hydroperoxide, reveal that a high-valent manganese-oxo species is formed as an epoxidizing intermediate via O-O bond heterolysis of Mn-OOH(R) species. The role of H2SO4 is proposed to facilitate the formation of a high-valent Mn-oxo species and to increase the oxidizing power and enantioselectivity of the Mn-oxo oxidant in olefin epoxidation reactions. Density functional theory (DFT) calculations support experimental results such as the formation of a Mn(V)-oxo species as an epoxidizing intermediate.

RNA parts often serve as critical components in genetic engineering. Here we report a design of translational activators which is composed of an RNA endoribonuclease (Csy4) and two exchangeable RNA modules. Csy4, a member of Cas endoribonuclease, cleaves at a specific recognition site; this cleavage releases a cis-repressive RNA module (crRNA) from the masked ribosome binding site (RBS), which subsequently allows the downstream translation initiation. Unlike small RNA as a translational activator, the endoribonuclease-based activator is able to efficiently unfold the perfect RBS-crRNA pairing. As an exchangeable module, the crRNA-RBS duplex was forwardly and reversely engineered to modulate the dynamic range of translational activity. We further showed that Csy4 and its recognition site, together as a module, can also be replaced by orthogonal endoribonuclease-recognition site homologues. These modularly structured, high-performance translational activators would endow the programming of gene expression in the translation level with higher feasibility.

The manganese complex Mn(S-PMB)(CF3SO3)2 was proven to be highly efficient in the catalytic oxidation of several benzylic and aliphatic secondary alcohols with H2O2 as the oxidant and acetic acid as the additive. A maximum turnover number of 4700 was achieved in the alcohol oxidation. In addition, the Hammett analysis unveiled the electrophilic nature of this manganese catalyst with N4 ligand.

A benzimidazole-based nonheme manganese complex efficiently catalyzes benzylic, aliphatic C-H as well as tertiary C-H oxidation with hydrogen peroxide as the oxidant in the presence of acetic acid as additive. (18)O labeling experiments suggest the reaction may proceed via a high-valent manganese-oxo intermediate.

Recently, we have indicated that microcystin-LR, a cyanobacterial toxin produced in eutrophic lakes or reservoirs, can increase invasive ability of melanoma MDA-MB-435 cells; however, the stimulatory effect needs identification by in vivo experiment and the related molecular mechanism is poorly understood. In this study, in vitro and in vivo experiments were conducted to investigate the effect of microcystin-LR on invasion and metastasis of human melanoma cells, and the underlying molecular mechanism was also explored. MDA-MB-435 xenograft model assay showed that oral administration of nude mice with microcystin-LR at 0.001-0.1 mg/kg/d posed no significant effect on tumor weight. Histological examination demonstrated that microcystin-LR could promote lung metastasis, which is confirmed by Matrigel chamber assay suggesting that microcystin-LR treatment at 25 nM can increase the invasiveness of MDA-MB-435 cells. In vitro and in vivo experiments consistently showed that microcystin-LR exposure increased mRNA and protein levels of matrix metalloproteinases (MMP-2/-9) by activating phosphatidylinositol 3-kinase (PI3-K)/AKT. Additionally, microcystin-LR treatment at low doses (≤25 nM) decreased lipid phosphatase PTEN expression, and the microcystin-induced invasiveness enhancement and MMP-2/-9 overexpression were reversed by the PI3-K/AKT chemical inhibitor LY294002 and AKT siRNA, indicating that microcystin-LR promotes invasion and metastasis of MDA-MB-435 cells via the PI3-K/AKT pathway.

In this work, a higher concentration of Ti ions are incorporated into hydrothermally grown Ti-doped (2.2% by atomic ratio) micro-nanostructured hematite films by an in situ solid-state reaction method. The doping concentration is improved from 2.2% to 19.7% after the in situ solid-state reaction. X-ray absorption analysis indicates the substitution of Fe ions by Ti ions, without the generation of Fe²⁺ defects. Photoelectrochemical impedance spectroscopy reveals the dramatic improvement of the electrical conductivity of the hematite film after the in situ solid-state reaction. As a consequence, the photocurrent density increases 8-fold (from 0.15 mA/cm² to 1.2 mA/cm²), and it further increases up to ∼1.5 mA/cm² with the adsorption of Co ions. Our findings demonstrate that the in situ solid-state reaction is an effective method to increase the doping level of Ti ions in hematite films with the retention of the micro-nanostructure of the films and enhance the photocurrent.

This study aimed to explore the molecular mechanisms behind the stimulation effects of microcystin-LR (a well-known cyanobacterial toxin produced in eutrophic lakes or reservoirs) on cancer cell invasion and matrix metalloproteinases (MMPs) expression. Boyden chamber assay showed that microcystin-LR exposure (>12.5 nM) evidently enhanced the invasion ability of the melanoma cells (MDA-MB-435). Tumor Metastasis PCR Array demonstrated that 24 h microcystin-LR treatment (25 nM) caused overexpression of eight genes involved in tumor metastasis, including MMP-2, MMP-9, and MMP-13. Quantitative real-time PCR, Western blotting and gelatin zymography consistently demonstrated that mRNA and protein levels of MMP-2/-9 were increased in the cells after microcystin-LR exposure (P < 0.05 each). Immunofluorescence assay and electrophoretic mobility shift assay revealed that microcystin-LR could activate nuclear factor kappaB (NF-κB) by accelerating NF-κB translocation into the nucleus and enhancing NF-κB binding ability. Furthermore, addition of NF-κB inhibitor in culture medium could suppress the invasiveness enhancement and MMP-2/-9 overexpression. This study indicates that microcystin-LR can act as a NF-κB activator to promote MMP-2/-9 expression and melanoma cell invasion, which deserves more environmental health concerns.

Iron(III) oxide photoelectrodes show promise in water oxidation applications. In this study, micro-nano-structured hematite films are synthesized, and Ti ions are doped to improve photoelectric conversion efficiency. The photocurrent increases for enhanced electrical conductivity. Further enhanced photocurrent is achieved for Fe(2)O(3):Ti/ZnFe(2)O(4) heterojunction electrodes. Cyclic voltammograms combined with optical absorbance examinations demonstrate that the conduction and valence band edges of ZnFe(2)O(4) shift from those of Ti doped Fe(2)O(3) to the negative direction, which facilitates the efficient separation of electron-hole pairs at the Fe(2)O(3):Ti/ZnFe(2)O(4) interface. These findings demonstrate that, by doping hematite and by engineering the interface between the hematite and the electrolyte, charge separation can be effectively promoted and photocurrent density can be dramatically increased.

Photocatalytic TiO 2 was derivatized with an amino silane to give a positively charged colloidal suspension in water. UV irradiation of the cationic titania oxidized the organo silane coating converting the titania to a negatively charged colloid. Irradiation of mixed suspensions of cationic titania and cationic polyvinylamine microgel induced catastrophic flocculation. Electrophoresis and XPS evidence suggests that the UV removed the amine groups from the titania resulting in heteroflocculation of anionic titania with cationic microgel particles.

A novel class of lymphocyte function-associated antigen-1 (LFA-1) inhibitors is described. Discovered during the process to improve the physicochemical and metabolic properties of BIRT377 (1, Figure 1), a previously reported hydantoin-based LFA-1 inhibitor, these compounds are characterized by an imidazole-based 5,5-bicyclic scaffold, the 1,3,3-trisubstituted 1H-imidazo[1,2-alpha]imidazol-2-one (i.e. structure 3). The structure-activity relationship (SAR) shows that electron-withdrawing groups at C5 on the imidazole ring benefit potency and that oxygen-containing functional groups attached to a C5-sulfonyl or sulfonamide group further improve potency. This latter gain in potency is attributed to the interaction(s) of the functionalized sulfonyl/sulfonamide groups with the protein, likely polar-polar in nature, as suggested by SAR data. X-ray studies revealed that these bicyclic inhibitors bind to the I-domain of LFA-1 in a pattern similar to that of compound 1.