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In recent years, host-guest interactions of macrocycles have attracted much attention as an emerging method for enhancing the intersystem crossing of pure organic room-temperature phosphorescence. In this work, we utilize cucurbit[8]uril (Q[8]) to specifically recognize synthetic bromophenyl pyridine derivatives (BPCOOH) to construct a highly stable charge-transfer dimer, where the bromophenyl pyridine moiety of BPCOOH is encapsulated by Q[8] in a 1:2 host/guest ratio. The assemblies exhibit specific recognition and detection properties for dodine on both fluorescence and phosphorescence spectra. Subsequently, the solid films were prepared by introducing carboxymethylcellulose sodium into the assemblies, which greatly enhanced its RTP performance by increasing the noncovalent bonding interactions, enabling the visualization of high-strength RTP and quantitative testing of the solid state. Finally, this material was used for the application of portable indicator papers to achieve rapid and visualized detection of dodine in daily life, which provides more possibilities for the potential applications of cucurbit[

A novel orthogonal supramolecular polymer (Q[10]-TPDPB-Lu

An expedient synthesis of the nonreducing hexasaccharide fragment of axinelloside A has been completed via a linear stepwise glycosylation approach. Challenges involved in the synthesis include the highly stereoselective construction of five consecutive 1,2-icis/i-glycosidic linkages and the formation of a sterically crowded 2,3-disubstituted l-fucoside subunit. Protecting group-directing glycosylation strategies such as the remote participation effect of the benzoyl substituent and the stereocontrolling effect of the 4,6-iO/i-benzylidene group were employed for the synthesis of the desired 1,2-icis/i-glycosidic linkages. Moreover, the 2,3-branched l-fucoside framework was established through a 3-iO/iand then 2-iO/iglycosylation sequence in which the 3-hydroxyl group of the core l-fucose unit was glycosylated first and then the 2-hydroxyl. The synthetic hexasaccharide is properly protected, so it can be employed as a precursor to synthesize its natural form.

Cancer-derived small extracellular vesicles (csEVs) play critical roles in the genesis and development of various cancers. However, accurate detection of low-abundance csEVs remains particularly challenging due to the complex clinical sample composition. In the present study, we constructed a

Potassium ferricyanide in an aqueous solution is easily decomposed into highly toxic substances (potassium cyanide and hydrogen cyanide) by light or alkaline action, which poses a major hazard to environmental and human health. Here, a reticulated aggregation-induced emission (AIE) supramolecular polymer material (TPAP-Mb@

Aberrant energy metabolism not only endows tumor cells with unlimited proliferative capacity but also contributes to the establishment of the glucose-deficient/lactate-rich immunosuppressive tumor microenvironment (ITM) impairing antitumor immunity. Herein, a novel metabolic nanoregulator (D/B/CQ@ZIF-8@CS) was developed by enveloping 2-deoxy-d-glucose (2-DG), BAY-876, and chloroquine (CQ) into zeolitic imidazolate framework-8 (ZIF-8) to simultaneously deprive the energy/nutrition supply of tumor cells and relieve the ITM for synergetic tumor starvation-immunotherapy. Aerobic glycolysis, glucose uptake, and autophagy flux could be concurrently blocked by D/B/CQ@ZIF-8@CS, cutting off the nutrition/energy supply and the source of lactate. Furthermore, inhibition of glucose uptake and aerobic glycolysis could effectively reverse the glucose-deficient/lactate-rich ITM, thus functionally inactivating regulatory T cells and augmenting anti-CTLA-4 immunotherapy. Such a two-pronged strategy would provide new insights for the design of metabolic intervention-based synergistic cancer therapy.

Cancer is a malignant tumor with the highest mortality of human diseases. The early diagnosis of cancer can greatly reduce its mortality. Ultracentrifugation is the most commonly employed technique to separate small extracellular vesicles (sEVs) due to their small size and rare abundance, but the low separation efficiency is a major concern. Herein, we proposed a DNAzyme-triggered assembly and disassembly system that converted single nano-sized sEVs into clusters that could be conveniently enriched by ordinary centrifugation and then be broken into single sEVs in the presence of magnesium ions. The simultaneous quantification of sEVs was realized by recording the increase in fluorescence upon nucleic acid cleavage, and a detection limit as low as 54 particles/μL was achieved. The whole analytical procedure could be completed in 1.5 h without the assistance of ultracentrifugation. Efficient enrichment and accurate quantification of sEVs are enabled through the proposed approach, broadening the potentials of sEVs in biological science, biomedical engineering, and personalized medicine.

Relying on the supramolecular self-assembly of twisted cucurbit[14]urils (

Activation of molecular oxygen plays a crucial role in natural organisms and the modern chemical industry. Herein, we report a Mn-Co dual-single-atom catalyst that exerts a specific synergy in boosting O

Unification of the techniques of ultrafast science and scanning tunneling microscopy (STM) has the potential of tracking electronic motion in molecules simultaneously in real space and real time. Laser pulses can couple to an STM junction either in the weak-field or in the strong-field interaction regime. The strong-field regime entails significant modification (dressing) of the tunneling barrier of the STM junction, whereas the weak-field or the photon-driven regime entails perturbative interaction. Here, we describe how photons carried in an ultrashort pulse interact with an STM junction, defining the basic fundamental framework of ultrafast photon-induced tunneling microscopy. Selective dipole coupling of electronic states by photons is shown to be controllable by adjusting the DC bias at the STM junction. An ultrafast tunneling microscopy involving photons is established. Consolidation of the technique calls for innovative approaches to detect photon-induced tunneling currents at the STM junction. We introduce and characterize here three techniques involving dispersion, polarization, and frequency modulation of the laser pulses to lock-in detect the laser-induced tunneling current. We show that photon-induced tunneling currents can simultaneously achieve angstrom scale spatial resolution and sub-femtosecond temporal resolution. Ultrafast photon-induced tunneling microscopy will be able to directly probe electron dynamics in complex molecular systems, without the need of reconstruction techniques.

A series of hydrogels containing guanidine-based polymers using a poloxamer as the matrix were prepared to provide novel wound dressings with antibacterial and repairing-promotion properties for skin wounds. Herein, we developed a series of antibacterial hydrogels, the cationic guanidine-based polymer polyhexamethylene guanidine hydrochloride (PHMG) with poloxamer aqueous solution (12%, w/w) simplified as PHMGP, chitosan (CS)-cross-linked PHMG (referred to as PHMC) with poloxamer aqueous solution simplified as PHMCP, and hyaluronic acid (HA)-modified PHMG (referred to as PHMH) with poloxamer aqueous solution simplified as PHMHP, for enhancing full-thickness skin wound healing. The characterizations, antimicrobial activity, cytotoxicity, and in vivo full-thickness wound-healing capability of these hydrogels were analyzed and evaluated. The results show that though PHMGP possesses great bactericide properties, its cytotoxicity is too strong to support skin regeneration. However, after modified with CS or HA, PHMCP and PHMHP showed good biocompatibility and antimicrobial properties against Gram-positive and Gram-negative bacteria that are commonly present in injured skin. Both PHMCP and PHMHP hydrogels exhibited upgraded wound-healing efficiency in full-thickness skin defects, characterized by a shorter wound closure time, faster re-regeneration, and the earlier formation of skin appendages, compared with those of control or pure poloxamer treatments. Their biological mechanism was detected. Both PHMCP and PHMHP can regulate the related biofactors during the skin repair process such as interleukin-1β (IL-1β), interleukin-6 (IL-6), transforming growth factor beta-1(TGF-β1), alpha-smooth muscle actin (α-SMA), and vascular endothelial growth factor, to promote wound healing with less serious scarring. In short, hydrogels with excellent capabilities to inhibit microorganism infection and promote wound healing were developed, which will shed light on designing and producing wound dressings with promising applications in future.

The recent use of cryoprotectant replacement method for solving the easy drying problem of hydrogels has attracted increasing research interest. However, the conductivity decrease of organohydrogels due to the induced insulating solvent limited their electronic applications. Herein, we introduce the Hofmeister effect and electrostatic interaction to generate hydrogen and sodium bonds in the hydrogel. Combined with its double network, an effective charge channel that will not be affected by the solvent replacement, is therefore built. The developed organohydrogel-based single-electrode triboelectric nanogenerator (OHS-TENG) shows low conductivity decrease (one order) and high output (1.02-1.81 W/m2), which is much better than reported OHS-TENGs (2-3 orders, 41.2-710 mW/m2). Moreover, replacing water with glycerol in the hydrogel enables the device to exhibit excellent long-term stability (four months) and temperature tolerance (-50-100 °C). The presented strategy and mechanism can be extended to common organohydrogel systems aiming at high performance in electronic applications.

Proteogenomic identification of translated small open reading frames in human has revealed thousands of microproteins, or polypeptides of fewer than 100 amino acids, that were previously invisible to geneticists. Hundreds of microproteins have been shown to be essential for cell growth and proliferation, and many regulate macromolecular complexes. One such regulatory microprotein is NBDY, a 68-amino acid component of the human cytoplasmic RNA decapping complex. Heterologously expressed NBDY was previously reported to regulate cytoplasmic ribonucleoprotein (RNP) granules known as P-bodies and reporter gene stability, but the global effect of endogenous NBDY on the cellular transcriptome remained undefined. In this work, we demonstrate that endogenous NBDY directly interacts with the human RNA decapping complex through EDC4 and DCP1A and localizes to P-bodies. Global profiling of RNA stability changes in NBDY knock out (KO) cells reveals dysregulated stability of over 1400 transcripts. DCP2 substrate transcript half-lives are both increased and decreased in NBDY KO cells, which correlates with 5′ UTR length. NBDY deletion additionally alters the stability of non-DCP2 target transcripts, possibly as a result of downregulated expression of nonsense-mediated decay (NMD) factors in NBDY KO cells. We present a comprehensive model of the regulation of RNA stability by NBDY.

Devices operating with excitons have promising prospects for overcoming the dilemma of response time and integration in current generation of electron- or/and photon-based elements and devices. Although the intrinsic properties including edges, grain boundaries, and defects of atomically thin semiconductors have been demonstrated as a powerful tool to adjust the bandgap and exciton energy, investigating the intrinsic modulation of spatiotemporal dynamics still remains challenging on account of the short exciton diffusion length. Here, we achieve the attractive remote lightening phenomenon, in which the emission region could be far away (up to 14.6 μm) from the excitation center, by utilizing a femtosecond laser with ultrahigh peak power as excitation source and the edge region with high photoluminescence efficiency as a bright emitter. Furthermore, the ultrafast transition between exciton and trion is demonstrated, which provides insight into the intrinsic modulation on populations of exciton and trion states. The complete cascaded physical scenario of exciton spatiotemporal dynamics is eventually established. This work can refresh our perspective on the spatial nonuniformities of CVD-grown atomically thin semiconductors and provide important implications for developing durable and stable excitonic devices in the future.

Decapping is the first committed step in 5'-to-3' RNA decay, and in the cytoplasm of human cells, multiple decapping enzymes regulate the stabilities of distinct subsets of cellular transcripts. However, the complete set of RNAs regulated by any individual decapping enzyme remains incompletely mapped, and no consensus sequence or property is currently known to unambiguously predict decapping enzyme substrates. Dcp2 was the first-identified and best-studied eukaryotic decapping enzyme, but it has been shown to regulate the stability of

MoSe2 is an efficient catalyst for the hydrogen evolution reaction (HER) and can potentially replace conventional catalysts composed of noble metals such as Pt. The HER activity of MoSe2 originates...

This study reports detection of specific phosphorylation sites installed on a small open reading frame-encoded polypeptide or microprotein called NBDY. NBDY phosphorylation sites were mapped using phosphoproteomics and antibody-based validation. NBDY is phosphorylated during growth factor signaling and cell division, and quantitative fluorescence microscopy was used to show that NBDY phosphorylation is required for disappearance of cytoplasmic RNA-protein granules called P-bodies during these cellular processes. Because P-bodies have properties of liquid-liquid phase separated membraneless orgaenelles, reductionist system to investigate NBDY phase separation. Purified NBDY was shown to form complex coacervates in the presence of RNA via fluorescence microscopy and turbidity measurements, and phosphorylation by a kinase in vitro promotes liquid phase remixing.

CH4 purification and CO2 removal by hydrate-based separation method from the simulated biogas (64 mol % CH4/CO2) were investigated in tetrabutylammonium bromide (TBAB) solution. Three different hyd...

The dangling-bond-free surfaces of van der Waals (vdW) materials make it possible to build ultrathin junctions. Fundamentally, the interfacial phenomena and related optoelectronic properties of vdW junctions are modulated by the interlayer coupling effect. However, the weak interlayer coupling of vdW heterostructures limits the interlayer charge transfer efficiency, resulting in low photoresponsivity. Here, a bilayer MoS2 homogeneous junction is constructed by stacking the as-grown onto the self-healed monolayer MoS2. The homojunction barrier of ∼165 meV is obtained by the electronic structure modulation of defect self-healing. This homojunction reveals the stronger interlayer coupling effect in comparison with vdW heterostructures. This ultrastrong interlayer coupling effect is experimentally verified by Raman spectra and angle-resolved photoemission spectroscopy. The ultrafast interlayer charge transfer takes place within ∼447 fs, which is faster than those of most vdW heterostructures. Furthermore, the...

This study reports an ambient-air-tolerant approach for negative electrode prelithiation by using 1 M lithium-biphenyl (Li-Bp)/tetrahydrofuran (THF) solution as the prelithiation reagent. Key to this strategy are the relatively stable nature of 1 M Li-Bp/THF in ambient air and the unique electrochemical behavior of Bp in ether and carbonate solvents. With its low redox potential of 0.41 V vs Li/Li+, Li-Bp can prelithiate various active materials with high efficacy. The successful prelithiation of a phosphrous/carbon composite electrode and the notable improvement in its initial Coulombic efficiency (CE) demonstrates the practicality of this strategy.

Calcium silicate hydrate is proposed as a potential silicate fertilizer. It is the main phase of the by-product of a mild hydrochemical process used to extract alumina from coal fly ash. Its preparation by decomposing sodium calcium silicate hydrate, the residue after extracting alumina from coal fly ash, was investigated. The results revealed that the intermediate of the sodium calcium silicate hydrate was easily decomposed into calcium silicate hydrate in a dilute alkaline solution and an available silica content of 28.57% was obtained under the decomposition conditions of a 30 g/L Na2O solution, a liquid-volume to solid-mass ratio of 25, a reaction temperature of 150 °C and a reaction time of 4 h, with a stirring speed of 600 rpm. Subsequently, Si uptake experiments were conducted on wheat seedlings by hydroponics to test Si’s effects on their growth. The results proved that the Si concentration in the wheat seedling shoots was greatly enhanced from 1.213 mg/g to 3.983 mg/g when 0.02 g of calcium silicate hydrate was distributed in the pot in which 3.87 g of seeds were cultivated.

Dcp2 is an important enzyme that controls the stability of a subset of human cellular RNAs encoding functions such as transcription and immune responses. While >1800 Dcp2 substrates have been identified in human cells, compensatory gene expression changes secondary to genetic ablation of the DCP2 gene have complicated a complete mapping of its regulome. Cellpermeable, selective chemical ligands of Dcp2 could facilitate development of improved tools for elucidation of its function and cellular specificity. Here, we report the selection of a bicyclic peptide ligand of human Dcp2 from chemically cyclized phageencoded libraries, and evaluation of its affinity and selectivity for Dcp2 in vitro and in cells. Quantitative reverse transcription PCR (qRT-PCR) combined with a splinted ligation assay revealed that this stapled bicyclic peptide inhibits Dcp2 decapping activity toward specific RNA substrates inside human cells. We further demonstrate that CP21 increases formation of P-bodies, cellular liquid condensates enriched in intermediates of cellular RNA decay, in the same manner as deletion or mutation of Dcp2. Collectively, these results demonstrate development of a selective ligand of Dcp2 that modulates some of its functions inside cells. In the future, this molecule – and, more broadly, stapled peptide selection – may find utility in reverse chemical genetics to dissect the specificities of coexistent cellular RNA decay pathways.

Dcp2 is an important enzyme that controls the stability of a subset of human cellular RNAs encoding functions such as transcription and immune responses. While >1800 Dcp2 substrates have been identified in human cells, compensatory gene expression changes secondary to genetic ablation of the DCP2 gene have complicated a complete mapping of its regulome. Cellpermeable, selective chemical ligands of Dcp2 could facilitate development of improved tools for elucidation of its function and cellular specificity. Here, we report the selection of a bicyclic peptide ligand of human Dcp2 from chemically cyclized phageencoded libraries, and evaluation of its affinity and selectivity for Dcp2 in vitro and in cells. Quantitative reverse transcription PCR (qRT-PCR) combined with a splinted ligation assay revealed that this stapled bicyclic peptide inhibits Dcp2 decapping activity toward specific RNA substrates inside human cells. We further demonstrate that CP21 increases formation of P-bodies, cellular liquid condensates enriched in intermediates of cellular RNA decay, in the same manner as deletion or mutation of Dcp2. Collectively, these results demonstrate development of a selective ligand of Dcp2 that modulates some of its functions inside cells. In the future, this molecule – and, more broadly, stapled peptide selection – may find utility in reverse chemical genetics to dissect the specificities of coexistent cellular RNA decay pathways.

Dcp2 is an important enzyme that controls the stability of a subset of human cellular RNAs encoding functions such as transcription and immune responses. While >1800 Dcp2 substrates have been identified in human cells, compensatory gene expression changes secondary to genetic ablation of the DCP2 gene have complicated a complete mapping of its regulome. Cellpermeable, selective chemical ligands of Dcp2 could facilitate development of improved tools for elucidation of its function and cellular specificity. Here, we report the selection of a bicyclic peptide ligand of human Dcp2 from chemically cyclized phageencoded libraries, and evaluation of its affinity and selectivity for Dcp2 in vitro and in cells. Quantitative reverse transcription PCR (qRT-PCR) combined with a splinted ligation assay revealed that this stapled bicyclic peptide inhibits Dcp2 decapping activity toward specific RNA substrates inside human cells. We further demonstrate that CP21 increases formation of P-bodies, cellular liquid condensates enriched in intermediates of cellular RNA decay, in the same manner as deletion or mutation of Dcp2. Collectively, these results demonstrate development of a selective ligand of Dcp2 that modulates some of its functions inside cells. In the future, this molecule – and, more broadly, stapled peptide selection – may find utility in reverse chemical genetics to dissect the specificities of coexistent cellular RNA decay pathways.

The thermodynamic equilibrium conditions for binary gas mixtures of CH4 and H2 in the presence of TBAB were measured using the T-cycle method in this study. The experiments were conducted in the temperature range from (282.37 to 296.45) K and the pressure range from (0.46 to 15.47) MPa. The mole fraction of H2 in gas mixtures varied from 0.15 to 0.85. The mass fraction of TBAB solution ranged from 0.10 to 0.50. The experimental results showed that the addition of TBAB can dramatically reduce the pressure required for hydrate formation at a fixed temperature. The equilibrium pressure increased along with the increasing composition of H2 in the gas mixture. In order to gain a better understanding on the impact of TBAB on the thermodynamic equilibrium conditions for binary gas mixtures, a comparison was made between our data and phase equilibrium conditions for THF hydrates formed from the same gas mixture. The results showed that the thermodynamic promoting effect of TBAB was superior to that of THF when th...

Here, we describe the formation of zeolite LiX fiber sorbents and postfabrication activation at temperatures of 350–400 °C for use in air separations. Two polymers were considered as the support matrices for the LiX zeolites: Torlon (polyamide-imide) and Matrimid (polyimide). Torlon-based fiber sorbents exhibit approximately 4% mass loss during the high-temperature (370 °C) activation required for zeolites, which is close to the glass transition temperature of these polymers. This mass loss is accompanied by the formation of pyrolytic side products that ultimately resulted in contamination of the LiX crystals and a 73% reduction in N2 sorption capacity at ambient temperatures. In contrast, Matrimid was found to be suitable for fiber sorbent synthesis with only 10–15% reduction in N2 sorption capacity observed upon the thermal activation. A LiX loading of 73% in monolithic fibers (i.e., no bore) by weight was achievable. Experimental breakthrough tests at 25 °C were conducted on an activated fiber module c...

Experimental measurement for the binding energy of hydrogen-bonds (HBs) has long been an attractive and challenging topic in chemistry and biochemistry. In the present study, the binding energy of OH···O HBs can be determined by 1H NMR technique using a set of model biomass-derived hydroxyl compounds, including furfuryl alcohol, isosorbide, tetrahydrofurfuryl alcohol, and (S)-3-hydroxytetrahydrofuran. By performing concentration- and temperature-variation experiments, we put forward a modified Arrhenius-type equation, in which the compensated natural logarithm of the chemical shift (ln δ + Δδ) is linearly correlated with 1/T. HBs energies can be directly determined by the slope of the plot, and are substantiated by density functional theory (DFT) theoretical calculations. This study provides a reliable method to measure the binding energy of OH···O HBs in hydroxyl-containing biomass-derived feedstocks.

Three liver hazards, two confirmed—hepatitis B virus (HBV) and aflatoxin (AFB), and one rarely studied in populations—microcystin (MC), simultaneously exist in tropical and humid areas; however, there are no epidemiological data on their risks in the same population. We conducted a community-based cross-sectional survey among 5493 adults in two rural towns and statistically analyzed the comparative and combinative effects of the three factors after detecting HBsAg and HBV DNA titers, determining estimated daily intakes (EDIs) of AFB1 and MC-LR and testing serum AST and ALT as liver injury markers for each participant. We observed a HBsAg(+) rate of 7.6%, a relatively high AFB1 exposure level (mean EDIAFB1 = 471.30 ng/d), and a relatively low MC-LR exposure level (mean EDIMC-LR = 228.25 ng/d). ORs for abnormal AST (2.42, 95%CI = 1.69–3.45) and ALT (2.87, 95%CI = 1.91–4.29) increased in HBV infections compared with HBV-unexposed participants but did not increase in participants with separate or combined exp...

Although the nephrotoxicity of microcystin and aflatoxin has been observed in animal and clinical cases, few population data are available. We conducted a cross-sectional study in Southwest China to investigate the association of renal function indicators (RFIs, including BUN, SCr, and eGFR) with exposure to microcystin and aflatoxin in 5493 members of the general population. Microcystin-LR levels in water and aquatic products and aflatoxin B1 levels in daily foods were measured by ELISA, and individual estimated daily intake (EDI) was assessed on the basis of the measurement and questionnaire. We found that participants with abnormal RFIs had a much higher mean level of microcystin-LR EDI than those with normal RFIs and that there was a significant increasing trend for abnormal rates and odds ratios of RFIs with increasing microcystin-LR EDI quartiles (p for trend = 0.000). Compared with the lowest quartile of microcystin-LR exposure, those in the highest quartile had significantly higher risks of abnormal BUN (OR = 1.80, 95% CI = 1.34-2.42), SCr (OR = 4.58, 95% CI = 2.92-7.21), and eGFR (OR = 4.41, 95% CI = 2.55-7.63), respectively, but no higher risk was found in subjects with higher AFB1 exposure. After adjustment for confounding factors, risk associations with microcystin-LR persisted. Consequently, our results suggest that microcystin, rather than aflatoxin, might be one important risk of renal-function impairment.

The use of electrode materials in their powdery form requires binders and conductive additives for the fabrication of the cells, which leads to unsatisfactory energy storage performance. Recently, a new strategy to design flexible, binder-, and additive-free three-dimensional electrodes with nanoscale surface engineering has been exploited in boosting the storage performance of electrode materials. In this paper, we design a new type of free-standing carbon quantum dot coated VO2 interwoven nanowires through a simple fabrication process and demonstrate its potential to be used as cathode material for lithium and sodium ion batteries. The versatile carbon quantum dots that are vastly flexible for surface engineering serve the function of protecting the nanowire surface and play an important role in the diffusion of electrons. Also, the three-dimensional carbon cloth coated with VO2 interwoven nanowires assisted in the diffusion of ions through the inner and the outer surface. With this unique architecture, the carbon quantum dot nanosurface engineered VO2 electrode exhibited capacities of 420 and 328 mAh g(-1) at current density rate of 0.3 C for lithium and sodium storage, respectively. This work serves as a milestone for the potential replacement of lithium ion batteries and next generation postbatteries.

The vulnerable restacking problem of tin disulfide (SnS2) usually leads to poor initial reversible capacity and poor cyclic stability, which hinders its practical application as lithium ion battery anode (LIB). In this work, we demonstrated an effective strategy to improve the first reversible capacity and lithium storage properties of SnS2 by growing SnS2 nanosheets on porous flexible vanadium nitride (VN) substrates. When evaluating lithium-storage properties, the three-dimensional (3D) porous VN coated SnS2 nanosheets (denoted as CC-VN@SnS2) yield a high reversible capacity of 75% with high specific capacity of about 819 mAh g(-1) at a current density of 0.65 A g(-1). Remarkable cyclic stability capacity of 791 mAh g(-1) after 100 cycles with excellent capacity retention of 97% was also achieved. Furthermore, discharge capacity as high as 349 mAh g(-1) is still retained after 70 cycles even at a elevated current density of 13 A g(-1). The excellent performance was due to the conductive flexible VN substrate support, which provides short Li-ion and electron pathways, accommodates large volume variation, contributes to the capacity, and provides mechanical stability, which allows the electrode to maintain its structural stability.

The Rh(III)-catalyzed C-H alkynylation of acrylamide derivative is realized using a hypervalent alkynyl iodine reagent. The use of a weakly coordinating directing group proved to be of critical importance. This reaction displays broad functional group tolerance and high efficiency, which opens a new synthetic pathway to access functionalized 1,3-enyne skeletons.

A self-decoupled porphyrin with a tripodal anchor has been synthesized and deposited on Au(111) using different wet-chemistry methods. Nanoscale electroluminescence from single porphyrin molecules or aggregates on Au(111) has been realized by tunneling electron excitation. The molecular origin of the luminescence is established by the vibrationally resolved fluorescence spectra observed. The rigid tripodal anchor not only acts as a decoupling spacer but also controls the orientation of the molecule. Intense molecular electroluminescence can be obtained from the emission enhancement provided by a good coupling between the molecular transition dipole and the axial nanocavity plasmon. The unipolar performance of the electroluminescence from the designed tripodal molecule suggests that the porphyrin molecule is likely to be excited by the injection of hot electrons, and then the excited state decays radiatively through Franck-Condon π*-π transitions. These results open up a new route to generating electrically driven nanoscale light sources.

Traditional in vitro nanotoxicity researches are conducted on cultured two-dimensional (2D) monolayer cells and thereby cannot reflect organism response to nanoparticle toxicities at tissue levels. This paper describes a new, high-throughput approach to test in vitro nanotoxicity in three-dimensional (3D) microtissue array, where microtissues are formed by seeding cells in nonsticky microwells, and cells are allowed to aggregate and grow into microtissues with defined size and shape. Nanoparticles attach and diffuse into microtissues gradually, causing radial cytotoxicity among cells, with more cells being killed on the outer layers of the microtissue than inside. Three classical toxicity assays [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT), glucose-6-phosphate dehydrogenase (G6DP), and calcein AM and ethidium homodimer (calcein AM/EthD-1)] have been adopted to verify the feasibility of the proposed approach. Results show that the nanotoxicities derived from this method are significantly lower than that from traditional 2D cultured monolayer cells (p0.05). Equipped with a microplate reader or a microscope, the nanotoxicity assay could be completed automatically without transferring the microtissue, ensuring the reliability of toxicity assay. The proposed approach provides a new strategy for high-throughput, simple, and accurate evaluation of nanoparticle toxicities by combining 3D microtissue array with a panel of classical toxicity assays.

This article describes a low cost method of generating silicon nanowire arrays that have similar structure and light trapping ability as moth-eye for matrix-free laser desorption/ionization mass spectrometry analysis of small molecules without matrix peak interference. The nanowire array is produced by combining low cost nanosphere lithography and metal nanoparticle-assisted chemical etching of silicon. Owing to their excellent light trapping ability over broad spectral range, silicon nanowire arrays can absorb incoming laser light efficiently, and convert laser energy to heat, which allows efficient desorption/ionization of intact peptide/proteins without matrix. Compared to existing matrix-free substrate such as porous silicon substrates, the biomimic silicon nanowire arrays are better in terms of lower laser energy, structural tunability, and low spatial resistance.

Charge carriers balance and triplet excitons confinement are two key factors determining the performance of phosphor-based organic light-emitting diodes (OLEDs). The characteristics of white OLED (WOLED) based on complementary blue and yellow phosphors could be easily manipulated by the insertion of an ultrathin interlayer between the two emitters. Both the electrical and the optical characteristics of WOLEDs are significantly dependent on the selection of the interlayers, which tailor charge carrier transportation and energy transfer. The interlayers ease the perplexity of probing the dynamics of charges and excitons. High efficiencies could also be achieved by the effective prevention of the high energy blue triplet excitons from diffusing into the adjacent low triplet states via Dexter transfer. The device with the nominal n-type interlayer and triplets confinement architecture reaches a power efficiency of 40.0 lm/W at ∼100 cd/m2 and a luminance of 1333 cd/m2 at a low voltage of 4.0 V.

3-(2'-, 3'-, and 4'-Hydroxybenzylidene)-7-methoxychroman-4-one (o-, m-, and p-HBMC) was synthesized for the clarification of the influence of the hydroxyl group at the B ring on the antioxidant activity of homoisoflavonoid. The three homoisoflavonoids used herein can reduce peroxynitrite. p-HBMC exhibited high activity to reduce singlet oxygen. Furthermore, o-, m-, and p-HBMC can scavenge the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS(*+)) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and galvinoxyl radicals. The rates of o-HBMC trapping of DPPH and galvinoxyl radicals were higher than those of m- and p-HBMC, whereas m-HBMC can trap ABTS(*+) rapidly. o-HBMC was found to possess high activity in the beta-carotene-linoleic acid bleaching test and to protect methyl linoleate against 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced oxidation efficiently. Finally, o-HBMC served as a prooxidant in Cu(2+)/glutathione (GSH)- and hydroxyl radical-mediated oxidations of DNA. m- and p-HBMC protected DNA against hydroxyl radical-mediated oxidation of DNA effectively, and o- and p-HBMC behaved as antioxidants to protect DNA against AAPH-induced oxidation. Thus, the hydroxyl group attaching to the ortho- and para-positions in the B ring was of importance for the homoisoflavonoid's enhancement of antioxidant activity.

Samples from naked oat were steeped and germinated under controlled conditions in an incubator. Changes of phenolic compounds and antioxidant activity were investigated in oats during steeping and germination. Results revealed that phenolic compounds and antioxidant activity of oats varied with the difference in steeping and germination stages. Compared with raw grains, short-term steeping treatment did not show significant effects (p0.05) on phenolic content. Germination can significantly result in the decrease in bound phenolic and the increase in free and total phenolics. Main phenolic acids and avenanthramides were isolated and quantified by HPLC analysis. During steeping, phenolic acids decreased (p0.05); avenanthramide N-(3',4'-dihydroxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid first decreased and then increased (p0.05), while avenanthramides N-(4'-hydroxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid and N-(4'-hydroxy-3'-methoxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid did not change significantly (p0.05). During germination, gallic and caffeic acids first increased (p0.05) and then decreased, whereas p-coumaric and ferulic acids and avenanthramides increased (p0.05). Nevertheless, avenanthramides did not change significantly (p0.05) during the last stage of germination. Oat extracts exhibited increasing high antioxidant activity with the steeping and germination going on, which may explain that antioxidant activity correlated (p0.01) significantly with the content of phenolic compounds.