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A metal-free, photoredox-catalyzed three-component cyanoalkylfluorination of alkenes under mild and redox-neutral conditions is reported. This protocol features use of readily available alkenes, oxime esters, and cost-effective nucleophilic fluoride reagents, giving diverse cyanoalkylfluorinated products with generally good yields. Excellent functional group tolerance and mild reaction conditions also render this protocol suitable for cyanoalkylfluorination of pharmaceutically relevant molecule-derived alkene.

The construction of carbon-heteroatom bonds is one of the most active areas of research in organic chemistry because the function of organic molecules is often derived from the presence of heteroatoms. Although considerable advances have recently been achieved in radical-involved catalytic asymmetric C-N bond formation, there has been little progress in the corresponding C-O bond-forming processes. Here, we describe a photoinduced copper-catalyzed cross-coupling of readily available oxime esters and 1,3-dienes to generate diversely substituted allylic esters with high regio- and enantioselectivity (>75 examples; up to 95% ee). The reaction proceeds at room temperature under excitation by purple light-emitting diodes (LEDs) and features the use of a single, earth-abundant copper-based chiral catalyst as both the photoredox catalyst for radical generation and the source of asymmetric induction in C-O coupling. Combined experimental and density functional theory (DFT) computational studies suggest the formation of π-allylcopper complexes from redox-active oxime esters as bifunctional reagents and 1,3-dienes through a radical-polar crossover process.

Pterocarya stenoptera is a tree species that occurs along rivers and has high tolerance to waterlogging. Identification of waterlogging response genes in the aboveground part of P. stenoptera will increase understanding of tolerance mechanisms under root waterlogging conditions. In this study, we employed four physiological indicators and comparative transcriptome sequencing to investigate the waterlogging tolerance mechanism in P. stenoptera. The physiological results showed that the aboveground part of P. stenoptera was not obviously affected by waterlogging. P. stenoptera enhanced waterlogging tolerance by increasing the synthesis of alpha-Linolenic acids and flavonoids and activating the jasmonic acid, ethylene, and auxin signaling pathways. Our results confirmed our hypothesis that P. stenoptera, a species that is widely distributed along rivers, has evolved a range of mechanisms in response to waterlogging. Our research will provide new insights for understanding the tolerance mechanism of species to waterlogging.

Phosphorus-31 nuclear-spin entanglements within Ca9(PO4)6 molecules (Posner molecules) have been proposed to be central for neural processing. However, this has yet to be proven experimentally. Relatedly, increasing calcium ion concentration in the cerebrospinal fluid has been proposed to enhance consciousness by accelerating Posner molecules' creation. A dependence on calcium isotope is also expected. Here we test these predictions experimentally by measuring the loss of righting reflex ED50 for mice to sevoflurane - an increase in loss of righting reflex ED50 indicates a higher level of consciousness and vice versa. Our mice's findings demonstrate that intracerebroventricular injection of EGTA enhances the sevoflurane-induced loss of righting reflex ED50 while injecting calcium-40 chloride or calcium-43 chloride causes an opposite effect. Further, the identical effects of calcium-40 and calcium-43 indicate an absence of calcium isotope dependence. Here, our findings disprove conventional proposals that calcium ion concentration correlates with consciousness.

Redox homeostasis is regulated by critical molecules that modulate antioxidant and redox signaling (ARS) within the cell. Imbalances among these molecules can lead to oxidative stress and damage to cell functions, causing a variety of diseases. Brahma-related gene 1 (BRG1), also known as SMARCA4, is the central ATPase catalytic subunit of the switch/sucrose nonfermentable (SWI/SNF) chromatin remodeling complex, which plays a core role in DNA replication, repair, recombination, and transcriptional regulation. Numerous recent studies show that BRG1 is involved in the regulation of various cellular processes associated with ARS. BRG1, as a major factor in chromatin remodeling, is essential for the repair of oxidative stress-induced DNA damage and the activation of antioxidant genes under oxidative stress. Consequently, a comprehensive understanding of the roles of BRG1 in redox homeostasis is crucial to understand the normal functioning as well as pathological mechanisms. In this review, we summarized and discussed the role of BRG1 in the regulation of ARS.

A new metal–organic framework was prepared based on a mixed ligand system of the designed nitrogen-rich 3,6-bis(2-methylimidazole)pyrimidine (b2mpm) and benzophenone 4,4′-dicarboxylic acid (H2bpndc...

The typical polymer electrolyte matrix has been limited to the chains consisting of -C-C- or -C-O-C- or -Si-O- backbone with different solvating groups for decades. In this work, the polymeric sulfur consisting of -(S-S)n- backbone with a high sulfur content (up to 90 wt % S) was reported for the first time. The flexible -(S-S)n- chains with high S atom density create an intense "solvating" environment for Li+ conduction, achieving an excellent Li+ conductivity of 1.69 × 10-3 S cm-1 at 80 °C. Benefiting from its unique thermoplasticity, a hot-rolling process was also developed for fabricating the poly-S membrane. The symmetric solid-state Li cell using the membrane showed a high cycling stability over 300 h. The work offers a novel platform for chemists to design new polymer electrolytes that are quite different with conventional carbon-based polymer electrolytes.

New photoinduced strategies towards radical reactions of strained molecules such as [1.1.1]propellane and bicyclo[1.1.0]butanes by photoredox or metallaphotoredox catalysis have recently been disclosed. Such strategies enable the controllable construction of 1,3-difunctionalized bicyclo[1.1.1]pentanes, cyclobutanes, and drug-like analogues, and offer new opportunities for reaction design of [1.1.1]propellane and other strained molecules.

Prebiotics can play an important role in functional foods. In this paper, casein and five probiotics were selected to study the effects on ACE inhibitory peptides in fermented milk of L. bulgaricus LB6 through Plackett-Burman design, so as to improve the production of ACE inhibitory peptides. The results showed that xylooligosaccharides (XOS), fructosaccharide (FOS) and inulin had the most significant effect on the yield of ACE inhibitory peptides. Optimization added the amount of the three prebiotics added, that is, the amount of XOS added was 0.7%, the amount of FOS added was 1.1%, and the amount of inulin added was 0.7%. It provides a basis for subsequent optimization experiments.

Recently, the design and development of nanozyme-based logic gates have received much attention. In this work, by engineering the stability of the nanozyme-catalyzed product, we demonstrated that the chromogenic system of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) can act as a visual output signal for constructing various Boolean logic operations. Specifically, cerium oxide or ferroferric oxide-based nanozymes can catalyze the oxidation of colorless TMB to a blue color product (oxTMB). The blue-colored solution of oxTMB could become colorless by some reductants, including the reduced transition state of glucose oxidase and xanthine oxidase. As a result, by combining biocatalytic reactions, the color change of oxTMB could be controlled logically. In our logic systems, glucose oxidase, β-galactosidase, and xanthine oxidase acted as inputs, and the state of oxTMB solution was used as an output. The logic operation produced a colored solution as the readout signal, which was easily distinguished with the naked eye. More importantly, the study of such a decolorization process allows the transformation of previously designed AND and OR logic gates into NAND and NOR gates. We propose that this work may push forward the design of novel nanozyme-based biological gates and help us further understand complex physiological pathways in living systems.

With the rapid development of biology and nanotechnology, designing nanomaterials with intrinsic enzyme-like activities has attracted huge attention in recent years. Herein, for the first time, we use zein as a new protein precursor to prepare N-rich carbonized zein nanosheets (C-Zein) via facile pyrolysis. Zein is an inert, biodegradable and sustainable natural biopolymer. After high-temperature carbonization, zein can be converted into highly catalytically active C-Zein, which can possess excellent peroxidase- and oxidase-like catalytic activities. Such intrinsic enzyme-like activities of C-Zein are closely related to its graphitization degree, the ratio of graphitic nitrogen and the formation of disordered graphene. Intriguingly, C-Zein also exhibits high photothermal conversion efficiency in the near-infrared (NIR) region. Coupling their unique photothermal and catalytic properties, the as-prepared C-Zein can act as a robust agent for synergistic photothermal-catalytic cancer treatment under the irradiation of NIR light. We expect that this work paves the way to use zein for designing efficient artificial enzymes and accelerate further growth in exploring its new biomedical and pharmaceutical applications.

By using the designed N-rich 3,6-bis(4-methyl-1H-imidazol-1-yl)pyridazine (b4mmp) and chiral d-camphoric acid (d-cam) ligands to react with cadmium acetate, a new bulk homochiral 3D metal–organic framework [Cd2(d-cam)2(b4mmp)(DMF)]n (1) has been synthesized. Compound 1 bears an uninodal 6-connected net structure with unprecedent topology, and it has a high thermostability. Moreover, the circular dichroism spectrum and photoluminescent properties for 1 were also investigated.

Toughness and tensile strength are important mechanical properties of polymers. However, it is generally very challenging to improve the toughness without an obvious decrease in the tensile strength, and vice versa, which greatly limits the applications of polymers. Here we developed a novel hydrogen bonding-based self-assembly technology for melt blending polymers to achieve a notable improvement in toughness without an obvious decrease in the tensile strength. Thermoplastic polyurethane (TPU)/polyamide 6 (PA6) blend was selected a model composite and its elongation at break increased significantly from 1150% (0 wt% PA6) to 1350% (7.5 wt% PA6) and 1375% (10 wt% PA6), without an obvious decrease in the tensile strength. We deeply investigated the relationship between microcosmic self-assembly and macroscopic mechanical properties in polymer melt blends. It was found that the hard and soft segment groups (urethane and ester) of TPU form new hydrogen bonds with the amide group of PA6 through hydrogen-bonded self-assembly during the melt blending process, while the intrinsic hydrogen bonding structure of TPU was obviously shielded and weakened. As a result, the TPU/PA6 melt blends showed a notable improvement in toughness without an obvious decrease in the tensile strength. Since most previous self-assembly studies were carried out in solution and there was little work focused on the industrial convenient melt blending method, our study paves the way for further studies on both theoretical studies and practical applications of polymer blends.

An approach is developed to fabricate supported AuPd nanoparticles (NPs) with high catalytic activity and good separability depending on these amino-modified polymer microspheres (Fe3O4@PS-NH2). After the careful surface modification with amino groups, the selective adsorption of these magnetic polymer carriers to p-nitrophenol (4-NP) is much available for the improvement of the catalytic activity of immobilized AuPd nanoparticles. Furthermore, the catalytic activity of the bimetallic catalyst could be tunable via controlling the surface coverage of palladium on Au nanoparticles. The catalytic activity of supported AuPd NPs (S-AuPd250%) for 4-NP reduction increased 3.78 times compared with that of isolated AuPd NPs. The catalytic activity (k/mAu) even reached 479.78 min−1 mg−1 as S-AuPd150% and was selected as the catalyst. In addition, these supported AuPd nanoparticles are easily and rapidly isolated by magnetic separation. Due to its high stability, these supported AuPd NPs could be recycled for 30 runs without any loss of catalytic activity. Thus, the high catalytic activity and easy separability of this supported AuPd NPs are efficiently combined together, which is showing great potential in nanocatalysts.

Developing a highly active, acid-resistant and low-cost catalyst which can perform well in aqueous solution has long been sought for practical and sustainable lignocellulosic biomass transformation. In this work, a series of Ce–P–Co heterogeneous catalysts were prepared by a convenient solvothermal method for catalytic hydrogenation of levulinic acid (LA) to gamma-valerolactone (GVL) in water. By comprehensive characterizations and catalytic measurements, the structure of the prepared Ce–P–Co samples was disclosed as (CePO4)m/Co2P composites with a modulated molar ratio (m) of 0.04–0.34. With the introduction of CePO4, the unique hydrogen activation on CePO4 markedly accelerated the reaction, with the GVL yield after 90 min on (CePO4)m/Co2P (45–97%) being much higher than on pure Co2P (26%), together with an attractive TOF of 0.27–0.61 s−1 on (CePO4)m/Co2P (comparable to precious metal catalysts). Further analysis of the kinetic and acidic features indicated a Langmuir–Hinshelwood mechanism, initiated by activation of H2 and LA on CePO4 and Co2P, respectively, followed by a surface reaction of the two activated species as the rate-determining step, as a plausible pathway for producing GVL from LA on (CePO4)m/Co2P. The consistent catalytic performance during recycling tests and the unchanged morphological, bulk and surface structure features of the used catalyst relative to the fresh catalyst confirmed that the (CePO4)m/Co2P structure was robust enough to endure the acidic aqueous environment for efficiently and sustainably converting LA to GVL. The advantages of high catalytic efficiency, stable, acid-resistant structure and low cost marked (CePO4)m/Co2P as a competitive and practical heterogeneous catalyst for sustainable, scaled-up lignocellulosic biomass transformation.

A series of environment-friendly plasticizers has been synthesized from castor oil through a mild esterification/epoxidation reaction. The modified epoxy acetylated castor oil (EACO) can plastify poly(vinyl chloride) (PVC) efficiently, even better than the commercial plasticizers dioctyl terephthalate (DOTP) and epoxidized soybean oil (ESO), in terms of in tensile strength, migration stability, solvent extraction stability and thermal stability. Specifically, the tensile strength and elongation at break of a PVC sample plastified by epoxy acetylated castor oil (EACO) were 18.5 and 10.0% higher than that of DOTP, and 13.9 and 23.8% higher than that of ESO, respectively. Volatility, migration, solvent extraction and thermal stability tests indicated that the presence of carbon-carbon double bonds and hydroxy groups reduce the compatibility of a plasticizer with PVC while the presence of epoxy groups and ester bonds can improve the plasticizing effect of the plasticizer on PVC. In addition, alkyl groups can improve the plasticizing effect on PVC while benzene rings increase the rigidity of the PVC. The design strategy based on castor oil highlights a sustainable avenue for preparing cost-effective and high-efficiency plasticizers.

Zinc-copper-indium sulfide (ZCIS)-alloyed quantum dots are emerging as a new family of low toxic I–III–VI semiconductors due to their broad and color-tunable emissions as well as large Stokes shifts. Here, we fabricated a series of ZCIS QDs with tunable PL wavelengths and band-gap energies via a facile strategy by varying the ratio of A1–3 stock (Cu+/In3+) to the B stock (Zn2+) content. The ZnS shell was formed to improve the PL emission efficiency of the core nanoparticles and the PL emission wavelength of the resulting ZCIS/ZnS NCs gradually blue-shifted with an increase in the number of shell layers, resulting in a wide range of emissions from 800 nm to 518 nm that can be tuned by the core compositions or shell layer numbers for ZCIS/ZnS. Finally, the long-chain ligands dodecanethiol/octadecylamine on the quantum dots' surface were efficiently replaced by (3-mercaptopropyl)trimethoxysilane, thus enabling their solubility in an ionic liquid, which was confirmed via GC-MS. It also benefited for the co-dissolution of the polymers and chemical binding with other materials through the reactive silanol group, which provide stable and well-distributed ZCIS/ZnS QDs composites or surface coating by the QDs.

A set of highly dispersed copper ceria catalysts were synthesized by using the CeMOF precursor featured rich nitrogen-containing ligand. Owing to the existence of coordination interactions between metal ions and nitrogen atoms, the copper ions could be adsorbed into the pore of Ce-MOF and stabilized by the ordered nitrogen atom on the pore wall. After calcinations, the generated CuO/CeO 2 catalyst featured more well-dispersed active sites, which was evidenced by varieties of characterizations such as FT-IR, UV-vis spectroscopy, PXRD, TEM, H 2 -TPR, Raman spectroscopy and XPS. The as-synthesized CuO/CeO 2 catalysts displayed outstanding catalytic activities and stabilities for preferential carbon monoxide oxidation in H 2 -rich stream.

Isothermal compression testing of 23% Cr low nickel duplex stainless steels, with different Mn concentrations, was investigated in the temperature range of 1173–1423 K, the strain rate range of 0.01–10 s−1 and with a height reduction of 70%. Increasing the Mn content from 6.3 to 14.1% affected the deformation dynamic softening behaviour of flow curves at lower temperature and higher strain rate. It was also observed that increasing the deformation stain rate contributed to flow softening, and was caused by dynamic recrystallization (DRX) as a function of Mn addition. Deformation microstructure analysis demonstrated that more complete austenite phase DRX occurred with 10.3% Mn addition than that with 6.3% Mn addition at 1 s−1, but an excessive Mn content of 14.1% was unfavourable due to the increase of austenite fraction and stacking fault energy enhancement. Increasing the strain rate to 10 s−1 promoted austenite phase DRX at 1323 K with the Mn addition under large strain. Meanwhile, the ferrite phase DRX occurred at 1173 K/1–10 s−1 with 6.3% Mn, and was weakened with higher Mn addition. Compared to the 6.3% and 14.1% Mn, continuous DRX occurred at 1323 K/1 s−1 with 10.3% Mn, due to the larger fraction of high angle misorientations. The values for the activation energy and Zener–Hollomon parameter decreased with Mn addition from 6.3 to 10.3%, and then increased with a higher Mn addition of 14.1%, indicating that a proper content of Mn addition can reduce the thermal deformation resistance and promote DRX. The constitutive equations for different Mn addition alloys were developed using a hyperbolic sine equation. Processing maps with different Mn addition for the strains of 0.3, 0.6 and 1.2 were established. The 10.3% Mn content sample corresponded to the lowest instability region, implying that the workability was improved with the middle Mn addition.

It is believed that inhaled anesthetics occupy hydrophobic pockets within target proteins, but how inhaled anesthetics with diverse shapes and sizes fit into highly structurally selective pockets is unknown. For hydroxide ions are hydrophobic, we determined whether hydroxide ions could bridge inhaled anesthetics and protein pockets. We found that small additional load of cerebral hydroxide ions decreases anesthetic potency. Multiple-water entanglement network, derived from Ising model, has a great ability to amplify ultralow changes in the cerebral hydroxide ion concentration, and consequently, amplified hydroxide ions account for neural excitability. Molecular dynamics simulations showed that inhaled anesthetics produce anesthesia by attenuating the formation of multiple-water entanglement network. This work suggests amplified hydroxide ions underlying a unified mechanism for the anesthetic action of inhaled anesthetics.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief who would like to withdraw this accepted article, due to serious errors in authorship and affiliations which breach the journal's ethical policies.

We recently develop an efficient single-step strategy to convert isolated mouse and human astrocytes into functional neurons by depleting the RNA binding protein PTB in isolated astrocytes in culture and directly in mouse brain. We show progressive conversion of astrocytes into new neurons that can innervate into endogenous neural circuits. Focusing on midbrain, we demonstrate efficient conversion of nigral astrocytes into dopaminergic neurons whose axons reconstruct the nigro-striatal circuit. Significantly, re-innervation of striatum is accompanied by restoration of dopamine levels and rescue of motor deficits. Herein, we present key methods employed in this study as stepwise protocols.

The effect of bromide and iodide on the transformation of humic acid (HA) and algal organic matter (AOM), and the formation of disinfection by-products (DBPs) during UV/chlorination were investigated. Experimental results indicated that the halides effectively inhibited mineralization, with multiple changes in organic molecule transformation due to differences in formation and speciation of reactive halogen species and free halogen. As a consequence, bromide and iodide also played important roles in DBP formation. The DBP yields in HA-containing water during UV/chlorination decreased in the order of iodide loaded > freshwater ≫ bromide loaded, whereas DBP formation in AOM-containing water decreased remarkably with halides added (freshwater > bromide loaded ≫ iodide loaded) at high UV fluence. Moreover, Pearson correlation analysis exhibited weaker correlation between DBPs and water parameters in AOM-containing water, while DBPs in HA-containing water exhibited better correlation with water parameters. For both simulated waters, the theoretical toxicity was calculated and peaked in bromide-containing water, whereas the calculated toxicity in iodide-containing water was comparable or slightly higher than that in freshwater. Therefore, UV/chlorine treatment may achieve good quality water with reduced DBP-associated toxicity in freshwater or iodide-containing water (iodide only), but careful consideration is needed when purifying source waters containing bromide (bromide only), especially for AOM/bromide-containing water.

In this study, we developed an in-situ cellular reprogramming strategy for potent restoration of vision in advanced/end-stage retinitis pigmentosa (RP). Via repressing PTB, an RNA binding protein critical for converting non-neuronal cells to the neuronal lineage, we successfully reprogramed Müller glia to a retinal neuronal fate, and then to cones. We demonstrated that this cellular reprogramming approach was able to rescue retinal photoreceptor degeneration and restore visual functions in two RP mouse models with total blindness, suggesting a novel universal strategy for treating end-stage degenerative diseases.

The adsorption of three haloforms (CHCl3, CHBr3 and CHI3) was studied using five different granular activated carbons (GACs), including acid washing carbon, coconut-shell carbon, briquetting carbon, coal and fibred carbon. The adsorption isotherms were fitted well using Freundlich model, and adsorption kinetics were fitted well using pseudo-second-order model. CHI3 was adsorbed most efficiently, followed by CHBr3 and CHCl3. Fibred carbon was the most efficient adsorbent for the studied haloforms. The adsorption capability of each GAC was calculated using the pseudo- second-order model which was then correlated to adsorbent properties. Generally, the surface area of GAC did not highly correlate to the amount of haloform adsorption. Highly positive correlations with methylene blue and iodine number were observed for CHBr3 and CHI3 adsorption capacity, but not for CHCl3. Micropores were correlated with CHCl3 adsorption capacity. Moreover, three models, including intraparticle diffusion, Byod kinetic and diffusion-chemisorption were used to illustrate the mechanisms of haloform adsorption mechanism. Film diffusion was determined to be the rate-limiting process and haloforms were adsorbed via chemical adsorption. The results of adsorption rate and capacity are crucial for practical application of haloform removal via GAC process.

Booster chlorination has been applied by many utilities for better chlorine-residual maintenance. In this paper, a new water-age based method for optimal location and dosage of booster disinfection has been proposed, as well as an uncertainty analysis of chlorine residuals. Chlorine-age, a novel indicator of water quality, is firstly introduced based on water age. By minimizing the total chlorine-age of nodes in a water distribution network (WDN), a new model for optimal booster location is proposed. The chlorine-age based model is independent of chlorine-decay simulation, and therefore avoids the complexity of obtaining kinetic parameters and prevents misleading results caused by inaccurate simulation of chlorine residuals. The uncertainties of chlorine residuals increase along with the distance and time consumption for delivering water. In this study, chlorine-age is employed to measure the uncertainties of nodal residuals, and optimal chlorine dosage is calculated considering the uncertainties. The proposed method has been tested on an example network and a real-life network to illustrate its validity and applicability. The results have shown that the method is feasible and reliable in practical application.

The influence of Mn addition on σ-phase precipitation kinetics and pitting corrosion of Fe-22Cr-1.9Ni-2.3Mo-0.2N-xMn low nickel type duplex stainless steel was investigated by medium- and high-temperature aging treatments of 600 °C and 800 °C. The microstructure analysis showed that the fine rod-shaped and coarsening dendritelike σ-phase precipitates formed at 600 °C and 800 °C, respectively, and the precipitate growth with the higher temperature was accelerated due to the partition of Mn, but Mn is not a strong σ-phase forming element like Cr, Mo during aging treatment at these two temperatures. At an early aging time of 800 °C, more precipitated nuclei with more Mn addition promote refinement of σ precipitates in later aging time. The kinetic behavior at 600 °C and 800 °C is related to diffusion-controlled growth of σ phase, and the σ-phase nucleation and growth are enhanced with more Mn addition and higher aging temperature due to a faster Mn diffusion rate. The difference in precipitation morphology for two aging temperatures was attributed to the different nucleation modes caused by kinetics parameter n variation. Increasing the aging temperature from 600 °C to 800 °C increased the susceptibility to pitting with higher Mn addition due to faster σ-phase precipitation kinetics.

Polymers containing the structure of N-heterocyclic carbenes (NHCs) have attracted much interest due to their superior complexing ability to metal ions and good recyclability, which make them promising candidates as solid supporters. Herein, we developed an easy method to synthesize polyimidazolium chloride salt (PImCl) via one-step method in mild conditions. After PImCl was chelated with palladium chloride in 3-chloropyridine, this NHC-Pd polymer was employed as the solid catalyst for Suzuki reactions of aryl bromides and phenylboronic acid. The catalytic activity of the NHC-Pd polymer was high for many different substrates. Moreover, the Suzuki reaction of 4-bromoanisole with phenylboronic acid could be catalyzed by this NHC-Pd polymer in mild conditions. Furthermore, this solid catalyst could be easily isolated by centrifugal separation. After several recycling runs, the catalytic activity decreased little. Compared with the conventional methods, this method was much simpler and more efficient, which showed enormous potential in preparing new heterogeneous supporter of porous polyimidazolium chloride salt.

Considering the long-term development of digital construction, a cost-effective and environmental printing material was designed with blast furnace slag as main cementitious material and sodium desulfurization ash as activator. However, weak alkaline environment lead to the insufficient 3D printability (e.g. yield stress, viscosity). Ethylene/vinyl acetate copolymer (EVA) was used to make up this defect, and it was found that there was a synergistic effect between EVA and sodium desulfurization ash (NS), which is beneficial to the improvement of the printing performance. The synergistic effect of EVA and NS was investigated in terms of fresh, hardened and microstructure properties. Experimental results show that under varying resting times and shear rates, the addition of 0.6−1.6% (i.e.by mass of binder) EVA could increase the yield stress and apparent viscosity of HVGS. Moreover, it was also found that the addition of EVA could help improve the polymerization degree of printing materials and increase the compressive strength of 28d by about 22%. To verify the practical value of the printing material, an industrial product was printed, and the maximum number of continuous printing layers can be up to 30 layers.

Vitreous enamel is a durable inorganic material that has been extensively used in our daily life for decoration and protection of the metallic substrates. It guarantees optimal corrosion protection to the covered substrates, but, on the other side, the brittle nature of its matrix highly limits its application. Here new enamel coatings were synthesized by adding silicon nitride with the contents of 0, 1.5, 2.5, 3.5, 5, and 7.5 wt%. Scanning electron microscope (SEM), X-ray diffraction (XRD), micro indentation, impact, thermal shock, and potentiodynamic polarization tests were conducted to evaluate the microstructure and engineering properties of the studied enamel coatings. Results showed that the addition of silicon nitride leads to a high internal porosity of the enamel coating, which consequently improves the resistances against cracking under indentation and impact loads. Especially, the silicon nitride modified enamel coatings were found to survive more than 100 cycles of thermal shocks. Despite the porosity rising, the addition of silicon nitride enhanced the corrosion resistance of enamel coatings at early immersion age, and all enamel coatings kept around 10 times lower corrosion rate than that of the uncoated steel at later immersion age. The findings of this work may provide a solution to steel protection against harsh high-temperature exposure and corrosive environments.

Autophagy is activated in the ischemic heart and is a process that is essential for survival, differentiation, development and homeostasis. 3,3'‑Diindolylmethane (DIM) is a natural product of the acid‑catalyzed condensation of indole‑3‑carbinol in cruciferous vegetables. Numerous studies have suggested that DIM has various pharmacological effects, including antioxidant, antitumor, anti‑angiogenic and anti‑apoptotic properties. However, the function of DIM on hypoxia‑induced cardiac injury remains to be elucidated. In the present study, H9c2 cells were pretreated with DIM (1, 5 and 10 µM) for 12 h and exposed to hypoxia for 12 h. It was demonstrated that DIM markedly attenuated the increased transcription of interleukin (IL)‑1β, IL‑6 and tumor necrosis factor‑α induced by hypoxia. In addition, the transcription of autophagy associated genes increased in the DIM pretreated group, compared with the hypoxia group. DIM additionally attenuated the increased apoptosis, as determined by terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and regulated the relative protein expression level of B cell lymphoma (Bcl) 2 associated X protein, Bcl‑xL and cleaved caspase 3. Furthermore, the phosphorylation of the 5' AMP‑activated protein kinase a (AMPKa) was activated and the phosphorylation of c‑Jun N‑terminal kinase (JNK) was inhibited. The effect of DIM on hypoxia‑induced apoptosis was abolished following pretreatment with JNK activator (anisomycin, 40 ng/ml). The effect of DIM on autophagy was reversed following pretreatment with AMPKa inhibitor (CpC, 20 µM) following stimulation with hypoxia. The results demonstrated that DIM prevented hypoxia‑induced inflammation and apoptosis and activated cardiomyocyte autophagy, which may be mediated by activation of AMPKa and inhibition of JNK pathways.

Supporting density of Au nanoparticles on the surface of magnetic carrier was carefully investigated because of its great effect on the catalytic activity. Micro-sized magnetic polymer beads (Fe 3 O 4 @PMMA) were employed to immobilize Au nanoparticles due to its easy surface modification and rapid magnetic separation. By controlling the supporting density and particles size of Au NPs, the catalytic activity of immobilized Au NPs in reducing p -nitrophenol was effectively improved. When 10 nm Au NPs were employed to be immobilized on the magnetic carrier with the density of 4292 μg/g, the catalytic activity of Fe 3 O 4 @PMMA/Au even approached to that of isolated Au NPs, which indicated that suitable supporting density of Au NPs might compensate some drawbacks of heterogeneous catalysts. It meant that the catalytic activity of Au NPs was not damaged even after its immobilization. Furthermore, this magnetic supported catalyst could be easily separated and recycled. After 23 runs of recycling, no significant loss of catalytic activity was found. This catalyst also performed high catalytic activity in continuous-flow column reactors, which showed much potential in practical application.

OBJECTIVE: To ascertain whether sleep abnormalities including daytime sleepiness, snoring, apnea, sleep disruption and sleep duration abnormity are significantly associated with hyperhomocysteinemia (Hhcy). METHODS: A total of 5992 participants were involved in the cross-sectional study. Sleep abnormalities were evaluated by a structured questionnaire. Hhcy was defined as plasma levels of homocysteine ≥15μm/L. RESULTS: After adjustment for age, gender, education, current smoking status and current drinking status, daytime sleepiness (OR, 1.597; 95%CI, 1.210-2.110, P=0.001), sleep duration 8h (OR, 1.205; 95%CI, 1.065-1.364, P=0.003) were significantly associated with Hhcy. While snoring (OR, 1.065; 95%CI, 0.950-1.195, P=0.279), apnea (OR, 1.170; 95%CI, 0.924-1.482, P=0.193), and sleep disruption (OR, 1.065; 95%CI, 0.852-1.331, P=0.580) were not. After further adjustment for body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, total cholesterol, physical activity, diabetes, coronary heart disease, stroke, depression, glomerular filtration rate, hypertension and hyperuricemia, still the increased OR could be found in the daytime sleepiness group (OR, 1.569; 95%CI, 1.145-2.150, P=0.005). However, sleep duration 8h groups (OR, 1.080; 95%CI, 0.883-1.320, P=0.453) were no longer significantly associated with Hhcy. CONCLUSIONS: Daytime sleepiness, but not sleep duration abnormity, snoring, apnea and sleep disruption was an independent risk factor for Hhcy.Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved. Language: en

Oxidative stress injury is involved in many cardiovascular diseases, like hypertension and myocardial infarction. Ubiquitination is a ubiquitous protein post‐translational modification that controls a wide range of biological functions and plays a crucial role in maintaining the homeostasis of cells in physiology and disease. Many studies have shown that oxidative stress damage is inextricably linked to ubiquitination. We demonstrate that Smurf2, an E3 ubiquitinated ligase, is involved in HUVEC apoptosis induced by oxidative stress to alleviate H2O2‐induced reactive oxygen species (ROS) production and the apoptosis of human umbilical vein endothelial cells (HUVECs). At the same time, we found that Smurf2 can bind the poly(ADP‐ribose) polymerase‐1(PARP1), and the interaction is enhanced under the stimulation of oxidative stress. We further study and prove that Smurf2 can promote PARP1 ubiquitination and degradation. Collectively, we demonstrate Smurf2 degradation of overactivated PARP1 by ubiquitin‐proteasome pathway to protect HUVEC and alleviate oxidative stress injury.

The elevated expression of poly(ADP-ribose) polymerase-1 (PARP1) and increased PARP1 activity, namely, poly(ADP-ribosyl)ation (PARylation), have been observed in cardiac remodeling, leading to extreme energy consumption and myocardial damage. However, the mechanisms underlying the regulation of PARP1 require further study. WWP2, a HECT-type E3 ubiquitin ligase, is highly expressed in the heart, but its function there is largely unknown. Here, we clarified the role of WWP2 in the regulation of PARP1 and the impact of this regulatory process on cardiac remodeling. We determined that the knockout of WWP2 specifically in myocardium decreased the level of PARP1 ubiquitination and increased the effects of isoproterenol (ISO)-induced PARP1 and PARylation, in turn aggravating ISO-induced myocardial hypertrophy, heart failure, and myocardial fibrosis. Similar findings were obtained in a model of ISO-induced H9c2 cells with WWP2 knockdown, while the reexpression of WWP2 significantly increased PARP1 ubiquitination and decreased PAPR1 and PARylation levels. Mechanistically, coimmunoprecipitation results identified that WWP2 is a novel interacting protein of PARP1 and mainly interacts with its BRCT domain, thus mediating the degradation of PARP1 through the ubiquitin-proteasome system. In addition, lysine 418 (K418) and lysine 249 (K249) were shown to be of critical importance in regulating PARP1 ubiquitination and degradation by WWP2. These findings reveal a novel WWP2-PARP1 signal transduction pathway involved in controlling cardiac remodeling and may provide a basis for exploring new strategies for treating heart disorders related to cardiac remodeling.

In order to increase the power density of the three-phase AC-DC converter, this paper presents a weight optimization method, which considers taking advantage of generator inductance. The optimization method analyzes the interdependence of all the constrains and design parameters, and studies the relationship between the weight of major components and the frequency. The key design parameters include power device, inductance, capacitance and heat sink. The weight estimation model of capacitor and heat sink to frequency are established. The optimal switching frequency to achieve highest power density is evaluated. Therefore, the high power density converter can be obtained.

Although the immobilization of gold nanoparticles (Au NPs) on the support is a conventional method for preventing them from aggregation and improving their separability at the cost of activity loss, herein, we developed a facile method to prepare supported Au NPs with the higher catalytic activity and better separability due to the selective adsorption of its functional surface. Firstly, the multi-functional carriers (amino-modified magnetic microspheres) were synthesized to immobilize Au NPs. Depending on its surface adsorption towards the reactant (p-nitrophenol), this carrier could greatly improve the mass transfer between p-nitrophenol (4-NP) and Au NPs resulting in the improvement of catalytic activity of supported Au NPs. The catalytic activity of supported Au NPs is increased more than 6.65 times compared with that of isolated Au NPs. Then, the effects of the particle size and supporting density of Au NPs on the catalytic activity were also investigated. Turnover frequency value of supported Au NPs (3.8 nm) reaches 16,000 h−1 when its surface density is controlled to 2211 μg g−1. Furthermore, the catalyst of Au/Fe3O4@PS-NH2 showed excellent catalytic activity when various nitrobenzene derivatives were employed as substrates. Remarkably, these supported Au NPs could be easily isolated by magnetic separation in 30 s. This catalyst could be recycled for 45 times without any loss in catalytic activity. The high catalytic activity and easy separability of this supported Au NPs make it much potential in large-scale application.

Bacterial cellulose (BC) features a nanofibrillar network structure that can provide a good template for quantum dots (QDs), to overcome the fluorescence quenching-effect of QDs in polymer composites. Here, we fabricated novel fluorescent aerogels with tunable emission by covalently binding environmentally-friendly ZnS(CuInS2)/ZnS core-shell quantum dots along the nanofibrillar BC. A new ligand of 3-(mercaptopropyl)trimethoxysilane allows QDs to transfer from toluene to alcohol solvent and stably bind to the BC. After supercritical CO2 drying, the resulting BC-QDs aerogels maintain the porous nanofibrillar morphology of BC with ultra-light-weight, the QDs are well-distributed along the BC fiber surfaces without aggregation. The emission wavelength can be tuned in a wide range from 470 to 750 nm by simply adjusting the QDs core component or shell layers. This work provides a new approach for fabricating QDs-polymer hydrogels and aerogels with well distributed QDs via chemical binding that potential as smart sensor, catalysis, and 3D display applications.

In recent years solid Li+ conductors with competitive ionic conductivity to those of liquid electrolytes have been reported. However, the incorporation of highly conductive solid electrolytes into the lithium-ion batteries is still very challenging mainly due to the high resistance existing at the solid-solid interfaces throughout the battery structure. Here, we demonstrated a universal interfacial modification strategy through coating a curable polymer-based glue electrolyte between the electrolyte and electrodes, aiming to address the poor solid-solid contact and thus decrease high interfacial resistance. The liquid glue exhibits both great wettability as well as chemical/electrochemical stability to most of the electrodes, and it can be easily solidified into a polymer electrolyte layer through a "post-curing" treatment. As a result, symmetric Li batteries with the glue modification exhibit much smaller impedance and enhanced stability upon plating/stripping cycles compared to the batteries without glue modification. The all-solid-state Li-S batteries with glue modification show significantly enhanced performances. The strategy of developing glue electrolytes to improve the electrode-electrolyte interface contact provides an alternative option for improving many other solid-state batteries. Accepted version

While solid polymer electrolytes are poised to be the key component of next-generation solid-state batteries, the low Li+ transference number of the polymer electrolytes limits their practical applications. Here, porous boron-containing covalent organic frameworks with different surface areas were synthesized and employed as functional additives for enhancing the Li+ transference number of the polymer electrolytes. The boron-containing frameworks enable strong adsorption of the anions of the lithium salt, leading to a significantly enhanced Li+ transference number of the polymer electrolyte containing COF additives. It is observed that solid-state cells assembled with the COF-containing polymer electrolytes exhibited remarkably decreased overpotentials and enhanced rate performances, which opens up new ways to apply porous organics in next-generation solid-state batteries.

Oxidative stress plays a major part in myocardial reperfusion injury. Cul4a is the core protein of CRLs E3 ubiquitin ligase complex; while it is known that Cul4a is responsible for various cancers, its role in cardiac function remains unclear. Hence, we have shown the protective function of Cul4a and its protection mechanism in oxidative stress-induced H9c2 cardiomyocyte apoptosis. Here, oxidative stress was induced by hydrogen peroxide (H2O2), CCK-8 assay and flow cytometry were used to analyze cell viability and apoptosis rate, western blot and immunofluorescence were used to quantitatively analyze the expression of protein, ROS fluorescence kit was used to detect reactive oxygen species (ROS) formation, and coimmunoprecipitation was used to identify protein interaction. In the results, it was found that Cul4a was involved in oxidative stress-induced H9c2 cell apoptosis and could inhibit H2O2-induced ROS generation and H9c2 cell apoptosis. Furthermore, we identified that when combining with PARP1, Cul4a could reduce its expression, and the interaction was enhanced under oxidative stress. In conclusion, our results indicate that Cul4a is a new protective factor involved in oxidative stress-induced cardiomyocyte injury and functions by tying and decreasing overactivated PARP1.

Poliumoside is the main active constituent of Callicarpa kwangtungensis Chun (CK), a traditional Chinese medicine for management of hemostasis. In this study, a rapid and selective ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/ Q-TOF-MS) method was developed and validated to quantify poliumoside in rat plasma. The targeted analytes in rat plasma were prepared through protein-precipitation method using 10% trichloroacetic acid (TCA). The chromatographic separation was performed on a Waters BEH C18 column (2.1 × 100 mm, 1.7 μm) by acetonitrile-water containing 0.1% formic acid. The calibration curve was linear over the range of 50 - 10,000 ng/mL (r2 > 0.99). The intra-day or inter-day precision was less than 7.97% and accuracy was within ?7.00% - 3.36%. The developed method was successfully applied to pharmacokinetic study of poliumoside in rat plasma. Although being rapidly absorbed (Tmax ≤ 30 min), poliumoside was poorly bioavailable after oral administration (the absolute bioavailability was only 0.69%).

The performances and operation lifetime of field emission (FE) cathodes made by spray-coating three different nanocarbon materials—carbon nanotubes (CNTs), graphene (GE), and carbon nanocoils (CNCs)—were compared. Though CNTs had the benefits of the lowest turn-on field, CNCs exhibited the most stable cycle-to-cycle repeatability and a significantly longer life than CNTs and GE under a continuous high-current-density operation. The microscopic morphology and Raman spectra of these nanocarbon emitters before and after the 50-h life tests were examined in order to understand the damage mechanism and the cause of their distinct performance decay behaviors. The results indicated that CNCs, whose diameters are significantly larger than those of CNTs and the thickness of GE, can withstand the thermal effects of high current density with the least degree of damage in the morphology and microstructure. According to our performance and life tests, CNTs are most suitable for low-voltage small-current FE applications because of their highest field enhancement factor and lowest turn-on field, while CNCs are a more favorable candidate for high-voltage long-term applications such as FE x-ray tubes.

Cellulose graft copolymers are an effective way to endow new properties to cellulose substrate, as well the rigidity, regularity, and helicity of the cellulose backbone could induce the self-assembly of supramolecular structures. In this work, right-handed helical poly(phenyl isocyanide)s (PPIn) were grafted selectively onto C-6-cellulose. Alkyne-terminated PPIn was synthesized by living polymerization of right-handed phenyl isocyanide monomer using an alkyne-terminated palladium(II) complex as an initiator/catalyst, and were grafted onto the C-6 of the cellulose backbone (Cell-6-g-PPIn) at various chain lengths using copper-catalyzed alkyne-azide cycloaddition (CuAAC) "click" chemistry. We confirmed the successful grafting by liquid 1H NMR and 13C NMR, as well as solid 13C NMR, FTIR, and GPC. After grafting onto cellulose, the right-handed chirality of PPIn was significantly increased by 111.2%. Additionally, the Cell-6-g-PPIn exhibited better chiral recognition of L-Phe-DNSP than PPIn alone. Therefore, the helical cellulose backbone has enhanced effect on preferred helix of PPIn.

Background: Increasingly, different heterocyclic systems have been introduced into the steroid nucleus to significantly enhance the antitumor activities of steroid molecules. However, in this study, few literature precedents describing the pyrazine heterocyclic-condensed modification to an A-ring of steroid monomers were found, although the pyrazine group is thought to be essential for the potent anticancer activity of clinically relevant drugs and natural steroid dimers. Methods and Results: Two series of novel A-ring fused steroidal pyrazines were designed and efficiently synthesized from commercially available progesterone via key &alpha, ketoenol intermediates. Through a cell counting kit-8 cytotoxic assay of 36 derivatives for three tumor cells, 14 compounds displayed significant antiproliferative activity compared to 5-fluorouracil, especially for human prostatic tumor cells (PC-3) in vitro. Further mechanistic studies indicated that the most active compound, 12n (IC50, 0.93 &mu, M, SI, 28.71), could induce the cell apoptosis of PC-3 cells in a dose-dependent manner and cause cell cycle arrest in the G2/M phase. The molecular docking study suggested that compound 12n fitted the active sites of cytochrome P450 17A1 (6CIZ) well. Conclusions: 12n might serve as a promising lead compound for the development of novel anticancer drugs. This facile ring-closing strategy may provide a novel and promising avenue for the cycloaddition reaction of the steroidal skeleton through &alpha, ketoenol intermediates.