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CO2-enhanced coalbed methane (CO2-ECBM) technology can be applied not only to extract coal seam gas, but also to geologically store a large amount of CO2 produced in various industries, thus reducing the CO2 concentration in the atmosphere and protecting the earth’s environment from the adverse effects of climate change. For CO2 injection and methane recovery from coal seams, the differences in the gas adsorption and diffusion characteristics due to the properties of the coal seam are crucial. In this study, first, intact and tectonic coals were collected to conduct a proximate analysis and high-pressure methane adsorption/desorption tests. Subsequently, the adsorption characteristics of the intact and tectonic coals with different particle sizes were analyzed. A time-dependent dynamic diffusion coefficient was introduced to investigate the diffusion characteristics of the two coals. The results showed that the intact and tectonic coals have higher adsorption capacity for CO2 than methane under the same particle size, demonstrating the potential for storing a large amount of CO2 in coal seams. The time-dependent dynamic diffusion coefficient decreased significantly in the initial stages and then tended to stabilize as the desorption progressed. To better explain the gas diffusion characteristics of the coal, a gas diffusion mechanism model was established to analyze the variation in the diffusion coefficient over time. In addition, a new method for reducing the pressure difference was proposed to maximize CO2 storage and methane recovery. Finally, the environmental implications and safety of CO2 storage in coal seams during the implementation of a CO2-ECBM project was analyzed.

There are numerous possible implications of nanotechnology in cancer therapy. To improve the therapeutic benefits of anticancer drugs nano-delivery systems (NDS) have been established with significant solubility, degradability and cytocompatibility. These NDS are the result of several advantages that high-performance nanoparticles hydroxyapatite (HA) advance rapidly in specific cancer treatments. Salinomycin is a pharmaceutical drug that serves to suppress tumour cells and the growth of many cancers as a chemical inhibitor. Nevertheless, Salinomycin’s low bioavailability is the main challenge to be used. In this work, HA chitosan-coated nanoparticles were utilised to enhance the efficiency and availability of Salinomycin as a pH-sensitive biopolymer. HA nanoparticles were initially produced using the sol-gel technique for this purpose. Then a coating of chitosan was coated with the nanocarrier under regulated circumstances, and the salinomycin medicine was encapsulated. For the characterization of nanocarriers were employed techniques such as scanning electron microscopy, X-ray diffraction, and Fourier transformations infrared spectroscopy. Different bioassays have tested nano-drugs developed in the second part. In this connection, we examined the cytotoxicity rate of the hepatocellular carcinoma HepG2 and Caco-2 by the MTT assay and the apoptosis induction rate by ethidium bromide and acridine orange staining method. It has been established that histological analysis is very suitable for nanomedicine, which does not cause apparent stress like swelling and inflammation organs of the mouse. The findings could offer solid evidence for nanoparticles’ apoptotic cell death mechanism and a novel cancer therapy approach.

The carbon–carbon double bonds (C=C) and graphene oxide (GO) in nitrile butadiene rubber (NBR) latex were reduced simultaneously by a novel one-pot to prepare the hydrogenated nitrile butadiene rubber/reduced graphene oxide (HNBR/RGO) nanocomposite in this study, using a hydrazine hydrate/hydrogen peroxide/copper sulfate catalyst. It is a water-based environmentally friendly and time-saving method where no organic solvent has served in the reduction process and hydrazine hydrate is completely consumed and will not harm the environment after the reduction process. HNBR/RGO can improve the electrical and thermal conductivity of HNBR, and the thermal conductivity of HNBR/RGO present better stability at high temperature (160 °C). RGO sheets are beneficial to shorten the curing time and increase cured rate index. And introducing RGO sheets may improve the thermal-oxidative aging resistance. The relationship between aging lifetime and temperature in HNBR/RGO can be estimated, and provide an opportunity for the practical application of HNBR.

Clonorosins A (1) and B (2), two novel indole alkaloids featuring unprecedented 6/5/6/6/5 and 6/5/5 cores, together with seven known indole-linked 2,5-diketopiperazine alkaloids (3-9), were isolated from the soil-derived fungus Clonostachys rosea YRS-06. The new structures were proposed through HR-MS, NMR, and ECD spectroscopic data. They were established by comparing the calculated NMR, ECD, and specific rotation data with the experimental. To assist in determining the absolute configuration of the chiral carbon in the side chain of 2,5-diketopiperazine derivatives, flexible analogues 3i-3iv were synthesized and analyzed. 1 was active against Fusarium oxysporum with an MIC value of 50 μg/mL. 7 and 8 showed excellent activity against human HeLa and HepG2 cells with IC50 values of 0.12-0.60 μM.

The biotransformation of organophosphate esters (OPEs) in white lupin (Lupinus albus) and wheat (Triticum aestivum L.) was investigated in hydroponic experiments with different phosphorus (P)-containing conditions. The hydrolysis rates of OPEs followed the order of triphenyl phosphate (TPHP) > tri-n-butyl phosphate (TnBP) > tris(1,3-dichloro-2-propyl) phosphate (TDCPP). Hydrolysis of OPEs was accelerated at P-deficient conditions, and faster hydrolysis took place in white lupin than in wheat. Coincidingly, the production of acid phosphatase (ACP) in both plants was promoted, and much higher intracellular and extracellular ACPs were observed in white lupin under P-deficient conditions. In vitro experiments revealed that ACP was a key enzyme to hydrolyze OPEs. The hydrolysis rates of OPEs were significantly correlated with the Hirshfeld charges, calculated by density functional theory, of the oxygen atom in the single P-O bond. Using ultra-high-performance liquid chromatography coupled with Orbitrap Fusion mass spectrometer, 30 metabolites were successfully identified. Some of these metabolites, such as sulfate-conjugated products, hydration of cysteine-conjugated products of TPHP, and reductively dechlorinated metabolites of TDCPP, were observed for the first time in plants. It is noteworthy that OPEs may transform into many hydroxylated metabolites, and special attention should be paid to their potential environmental effects.

A highly sensitive and selective method was developed for both UV–vis spectrophotometric and fluorimetric determination of organophosphorus pesticides (OPs). This method used silver nanoparticles (AgNPs) modified with graphitic carbon nitride (g-C3N4). The AgNPs reduced the fluorescence intensity of g-C3N4. Acetylthiocholine (ATCh) could be catalytically hydrolyzed by acetylcholinesterase (AChE) to form thiocholine, which induces aggregation of the AgNPs. This aggregation led to the recovery of the blue fluorescence of g-C3N4, with excitation/emission peaks at 310/460 nm. This fluorescence intensity could be reduced again in the presence of OPs because of the inhibitory effect of OPs on the activity of AChE. The degree of reduction was found to be proportional to the concentration of OPs, and the limit of fluorometric detection was 0.0324 μg/L (S/N = 3). In addition, the absorption of the g-C3N4/AgNPs at 390 nm decreased because of the aggregation of the AgNPs, but was recovered in presence of OPs because of the inhibition of enzyme activity by OPs. This method was successfully applied to the analysis of parathion-methyl in real samples., Graphical abstract Image 1, Highlights • A g-C3N4/AgNPs sensor could be used for the determination of organophosphorus pesticides (OPs). • The method exhibits ultra-sensitivity and high-selectivity toward OPs. • Double-signal OPs probe was developed with low cost, simple interpretation and easy handling.

Endogenous salicylic acid (SA) regulates leaf senescence, but the underlying mechanism remains largely unexplored. The exogenous application of SA to living plants is not efficient for inducing leaf senescence. By taking advantage of probenazole (PBZ)-induced biosynthesis of endogenous SA, we previously established a chemical inducible leaf senescence system that depends on SA biosynthesis and its core signaling receptor NPR1 in Arabidopsis thaliana. Here, using this system, we identified WRKY46 and WRKY6 as key components of the transcriptional machinery downstream of NPR1 signaling. Upon PBZ treatment, the wrky46 mutant exhibited significantly delayed leaf senescence. We demonstrate that NPR1 is essential for PBZ/SA-induced WRKY46 activation, whereas WRKY46 in turn enhances NPR1 expression. WRKY46 interacts with NPR1 in the nucleus, binding to the W-box of the WRKY6 promoter to induce its expression in response to SA signaling. Dysfunction of WRKY6 abolished PBZ-induced leaf senescence, while overexpression of WRKY6 was sufficient to accelerate leaf senescence even under normal growth conditions, suggesting that WRKY6 may serve as an integration node of multiple leaf senescence signaling pathways. Taken together, these findings reveal that the NPR1-WRKY46-WRKY6 signaling cascade plays a critical role in PBZ/SA-mediated leaf senescence in Arabidopsis.

Because of its limited light field mode and high Q value, the whispering-gallery-mode (WGM) cavity has been widely studied. In this study, we propose a simple, rapid, low-cost and no-manufacturing technology method that we call the drip-coating method to obtain an irregular cavity with arbitrary boundaries. By using polyvinyl alcohol (PVA) solution doped with rhodamine 6G, the irregular cavity with arbitrary boundaries was drip-coated on a high-reflection mirror, forming a WGM laser. The sample was pumped with a 532 nm pulsed laser, and the single-mode WGM and multi-WGM lasing were obtained. All WGMs are the vertical oscillation modes, which originate from both the total internal reflection of the PVA/air interface and vertical reflection of the PVA/mirror interface. The other boundaries of the cavity were not involved in the reflection and could have any shape. The mechanism of producing single-mode lasing is due to the action of the loss-gain cavity. Multi-WGM lasing is attributed to at least two groups of different WGMs existing in an irregular cavity. This can be confirmed by using a microsphere model and intensity correlation method. These results may provide an alternative for the design of WGM lasers.

Skin necrosis is the most serious complication of flap plastic surgery, which means the failure of the operation. Systemic administration rarely benefits the local area and can lead to side effects, while topical administration has poor permeability due to the skin barrier function. Currently, few of these common medical interventions can totally respond to the blood supply of the skin after surgery. Herein, a soluble microneedle (MN) patch made of hyaluronic acid was used to target the ischemic area in a painless and precise manner for transdermal drug delivery. Based on the important role of nitric oxide (NO) in angiogenesis, the thermosensitive NO donor (BNN6) and gold nanorods (GNRs) acting as photothermal agents were introduced into the microneedles (MNs). The hyperthermia induced by GNRs under near infrared (NIR, 808 nm) irradiation could enhance the penetration of drugs and facilitate NO release from BNN6. A series of corresponding experiments proved that the system played a significant promotion role in vascular regeneration, providing a painless, precise and NO-assisted treatment method for the ischemic perforator flaps.

Functionalization and morphological construction can promote lithium-ion storage performance of organic polymers. In this contribution, exceptional lithium ion storage performance is empowered to porous polyacrylonitrile (PAN) nanofibers via the integration of template-assisted electrospinning technology and thermal treatment. It is found that the atmosphere adopted during the annealing process controls the storage behaviors of Li+. Impressively, the samples annealed in air present competitive capacities, rate capabilities, and a stable lifetime, compared with other counterparts (PAN powders and PAN fibers treated in N2). Such enhancement in performance is attributed to the enriched oxygen-based functionalities (mainly C=O group) which guarantee a high specific capacity and the porous structure which facilitates the transportation of Li+ and electrons to improve the rate capability. It is envisioned that such morphology control and surface functionalization open up new horizons in the development of organic electrode materials with enhanced lithium-ion storage performances.

To step into the exploration of practical lithium–sulfur batteries as a high-energy output solution, several challenges such as the shuttle effect and sluggish reaction kinetics remain to be overcome. In this direction, we design a unique sulfur host derived from a honeycomb-like, porous nitrogen-doped carbon framework consisting of MoC with a three-dimensional architecture (H-MoC-NC) as both the adsorbent and catalyst for high-rate and long-lasting lithium-sulfur batteries. The interconnected carbon skeletons with a nitrogen-doped polar surface induce uniform sulfur distribution and fast charge transfer, which are supplied with strong physical confinement and the high-efficiency reaction of sulfur species. The adsorptive/catalytic MoC planes with maximized exposure endow sulfiphilic and catalytic sites that improve the ion conduction, chemical interaction, and redox kinetics in polysulfide regulation. Owing to the synergistic mode between conductive and catalytic functions, sulfur electrodes based on S/H-MoC-NC are characterized by enhanced battery performance with low polarization, high initial discharge capacity (1316 mA h g−1 at 0.1C), superior rate capacities (646 mA h g−1 at 3C), and decent cycling durability with a minimized capacity fading rate of 0.049% per cycle over 1000 cycles at 3C. The work not only probes the design of conductive and catalytic networks to be a promising architecture, but also demonstrates the enormous potential of MoC as an effective sulfur host for high-performance in the Li–S chemistry.

This report describes palladium-catalyzed C–H glycosylation and retro Diels–Alder tandem reaction via structurally modified norbornadienes (smNBDs). smNBDs were proposed to regulate the reactivity of the aryl-norbornadiene-palladacycle (ANP), including its high chemoselectivity and regioselectivity, which were the key to constructing C2 and C3 unsubstituted C4-glycosidic indoles. The scope of this substrate is extensive; the halogenated six-membered and five-membered glycosides were applied to the reaction smoothly, and N-alkyl (primary, secondary and tertiary) C4-glycosidic indoles can also be obtained by this method. In terms of mechanism, the key ANP intermediates characterized by X-ray single-crystal diffraction and further controlled experiments proved that the migration-insertion of smNBDs with phenylpalladium intermediate endows them with high chemo- and regioselectivity. Finally, density functional theory (DFT) calculation further verified the rationality of the mechanism.

Rational design and development of cost-effective, highly active and durable bifunctional electrocatalysts towards oxygen redox reactions is of critical importance but great challenge for the broad implementation of next-generation metal-air batteries for electric transportation. Herein, a high-performance electrocatalyst of cobalt and zinc sulfides nanocrystals embedded within nitrogen and sulfur co-doped porous carbon is successfully designed and derived from bimetallic metal-organic frameworks of cobalt and zinc containing zeolitic imidazolate frameworks. The unique nanostructure contains abundant electrocatalytic active sites of sulfides nanocrystals and nitrogen and sulfur dopants which can be fast accessed through highly porous structure originate from both zinc vaporization and sulfurization processes. Such bifunctional electrocatalyst delivers a superior half-wave potential of 0.86 V towards oxygen reduction reaction and overpotential of 350 mV towards oxygen evolution reaction, as well as excellent durability owing to the highly stable carbon framework with a great graphitized portion. The performance boosting is mainly attributed to the unique nanostructure where bimetallic cobalt and zinc provide synergistic effect during both synthesis and catalysis processes. The design and realization pave a new way of development and understanding of bifunctional electrocatalyst towards clean electrochemical energy technologies.

Production of chemicals and fuels from microcrystalline cellulose has inspired scholars’ attention. Deactivation of metallic catalysts including acid leaching and hydrothermal aggregation is still one of the core issues in these systems. To address these problems, we designed and fabricated a series of Ni-W/SiO2 catalysts, which were decorated by CxNy species using C- and N-sources and applied in cellulose conversion to C2,3 oxygenated compounds. The Ni-W/SiO2@CxNy catalysts, underwent complexing and self-assembling process, exhibited special heterojunctions, accompanying strong interactions mainly among Ni phase and CxNy layers. Catalytic results showed that the heterojunctions and outer CxNy layers extensively enhanced productions of hydroxyacetone (HDA) and ethylene glycol (EG) and promoted the hydrothermal stability through prospering in concentration of Lewis pairs from Ni N—N structure and immobilizing the metallic nanoclusters. 48.25% of EG was yielded under 5.0 MPa H2 pressurized 240 °C water for 2.0 h. The Lewis pair further improved the formation of HDA with 20.92% yield. High hydrothermal stability of Ni-W/SiO2@CxNy catalyst was proved according to the recycling results and trace leaching concentration of Ni and W. This construction of metallic catalysts exploited a new strategy to manufacture extraordinary durability of metallic nanoclusters for cellulose conversion under harsh reaction conditions.

Stereoselective construction of α-sialyl linkages is one of the most significant challenges in carbohydrate chemistry. In this research, we developed a novel strategy for stereoselective synthesis of α-linked sialosides by protecting the 5-N,4-O-positions of a sialyl donor with an oxazolidinone group and its C-1 carboxylic functionality with a cyanoethyl ester to promote α-glycosylation. We also adopted the more electrophilic N-bromosuccinimide as a promoter to readily activate p-tolyl thiosialoside at -78 °C. The sialylation using this sialyl donor gave excellent yields and α-selectivity. The new synthetic method was used to successfully construct naturally occurring α-sialosides having sialic acid linked to the 6-O- or 3-O-position of galactoside, or 8-O-position of another sialic acid, respectively, as well as other α-linked sialosides.

The lack of effective chemical tools capable of dynamic tracking of labile glyoxal species (GOS) [e.g., methylglyoxal (MGO) and glyoxal (GO)] levels with high selectivity over other relevant electrophilic species, particularly, formaldehyde (FA) and nitric oxide (NO), has significantly hampered the understanding of their roles in a complex metabolic network and disease progressions. Herein, we report the rational design of the bioinspired 4-(2-guanidino)-1,8-naphthalimide fluorescent probes NAP-DCP-1 and NAP-DCP-3 from arginine-specific protein modifications. These probes undergo facile reversible fluorophore-promoted deprotonation-cyclization of a guanidium ion with labile GOS to form exocyclic five-membered dihydroxyimidazolidines. The probe NAP-DCP-1 can differentiate GOS levels in the serum of diabetic mice and patients from nondiabetic ones, which correlate very well with glucose levels, providing the GOS level as a potential new biomarker for diabetes diagnosis. Notably, the endoplasmic reticulum (ER)-targeting probe NAP-DCP-3 enabled the study of GOS perturbation in ER under various stress conditions and led to the discovery that formaldehyde (FA), either exogenously added or endogenously generated, could induce GOS level increases in ER. This finding reveals the previous unknown connection of FA with upregulated GOS levels and suggests that GOS is a key metabolite in bridging one-carbon metabolism with glycolysis and the downstream cell redox status. Moreover, the probes also showed potentials in separate quantification of MGO and GO via ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and unexpected selectivity modulation for GO over MGO via two-photon excitation. It is expected that probes reported herein provide powerful tools to study GOS level modulations in complex biological networks and would facilitate GOS-associated basic research and discovery.

Background The purpose of the study is to describe the blood lipid levels of patients diagnosed with coronavirus disease 2019 (COVID-19) and to analyze the correlation between blood lipid levels and the prognosis of COVID-19 patients. Methods In the clinical retrospective analysis, a total of 228 adults infected with COVID-19 were enrolled between January 17, 2020 and March 14, 2020, in Changsha, China. One thousand one hundred and forty healthy participants with matched age and gender were used as control. Median with interquartile range and Mann-Whitney test were adopted to describe and analyze clinical data. The Kaplan-Meier (KM) curve and Cox regression analysis were used to analyze the correlation between high-density lipoprotein cholesterol (HDL-C) and the severity of COVID-19. Results Compared with control, COVID-19 patients showed significantly lower levels of total cholesterol (TC) [median, 3.76 vs 4.65 mmol/L, P = 0.031], triglyceride [median, 1.08 vs 1.21 mmol/L, P P P P = 0.032]. In comparison with patients with high HDL-C, patients with low HDL-C showed a higher proportion of male (69.57% vs 45.60%, P = 0.004), higher levels of C-reactive protein (CRP) (median, 27.83 vs 12.56 mg/L, P P = 0.001). Moreover, patients with low HDL-C at admission showed a higher risk of developing severe events compared with those with high HDL-C (Log Rank P = 0.009). After adjusting for age, gender and underlying diseases, they still had elevated possibility of developing severe cases than those with high HDL-C (HR 2.827, 95% CI 1.190–6.714, P = 0.019). Conclusions HDL-C level was lower in COVID-19 adult patients, and low HDL-C in COVID-19 patients was correlated with a higher risk of developing severe events.

The kinetics of hydrogenation of acrylonitrile butadiene rubber (NBR) latex by the action of diimide generated by hydrazine hydrate and hydrogen peroxide in the presence of copper sulfate at low temperature was studied by calculating the initial reaction rate constants. Altering reaction parameters of different reactant dosages such as carbon-carbon double bonds, hydrazine hydrate, hydrogen peroxide, and copper sulfate can be designed to calculate the initial reaction rate constant in a hydrazine hydrate/hydrogen peroxide/copper sulfate reaction system. The method of initial reaction rate constants gives rate constant and reaction order in the hydrogenation reaction of NBR latex calculated from the hydrogenation kinetic data. Based on these kinetic values, the kinetic equation of hydrogenation of NBR latex in this catalytic system at the temperature ranged from 5 to 65 °C and the hydrogenated reaction activation energy were studied in this paper. Graphical abstract

An efficient transition-metal-free tactic for the convergent synthesis of substituted dihydropyrroles and pyrroles by β-chloro-vinyl dithiane cyclization with a broad range of imines was developed. [3+2] Cyclization and aromatization occur under these reaction conditions providing biologically relevant dihydropyrroles and pyrroles in good yields.

The migration behaviour of an ionic liquid (IL) nano-droplet on a graphene surface under temperature gradients was studied using non-equilibrium molecular dynamics (MD) simulations. 1-ethyl-3-methy...

In this study, wheat (Triticum aestivum L.) was exposed to three of the most typical chlorinated organophosphate esters (OPEs), which are widely present in farmland soil, at environmental concentrations to assess their accumulation, disruption on metabolism, and oxidative stress in wheat. The three OPEs accumulated distinctly in the root and then translocated to the shoot. After exposure for 7 days, the content of chlorophyll b decreased, while the levels of carotenoid and activities of antioxidases, malonaldehyde, and reactive oxygen species increased significantly in both the root and shoot, indicating that the target OPEs caused significant oxidative stresses and affected photosynthesis in wheat. Untargeted metabolomics revealed concentration- and species-dependent metabolic responses of the three OPEs. Saccharides were downregulated, which might be due to the reduced photosynthesis activities. On the other hand, the chlorinated OPEs induced increases in respiration and antioxidative metabolites, revealing that the antioxidant system of wheat was active in scavenging ROS. The disturbance of tris(1,3-dichloro-2-propyl)phosphate on the metabolisms in wheat tissues was the strongest. These results contribute to the food safety and crop quality assessment of chlorinated OPEs and clarify the underlying mechanisms of their phytotoxicities.

Purpose In order to prepare functional Au nanoparticles with low toxicity and high antitumor properties, we have used fruit waste (banana peel) to synthesize a new dendrite-shaped gold nanoparticle and used it for the treatment of tumors. Methods Dendrite-shaped gold nanoparticle (Au-dendrite) was synthesized through a facile hydrothermal process. The banana peel was used as both the reducing agent and the protective agent for reducing chloroauric acid to obtain Au-dendrite. The safety assessment of the Au-dendrite was conducted by H&E staining of the mouse's eyelid skin and CCK-8 assay. The antitumor effects were evaluated through in vitro tumor cytotoxicity experiments and in vivo treatment of animal tumors. Results In this work, a new type of gold nanomaterial (Au-dendrite) was synthesized by using a common agricultural waste (banana peel) through a facile hydrothermal process without any extra chemical reducing agent or protective agent. Subsequent experiments showed that, compared with some classical Au nanomaterials, the as-synthesized gold nanocomposites have superior biocompatibility and impressive characteristics of dual inhibition toward tumor growth and migration. Conclusion We successfully synthesized a dendrite-shaped gold nanocomposite which was derived from a common agricultural waste (banana peel). A facile and environmentally friendly synthetic process was proposed accordingly without regular chemical additives. The as-prepared Au-dendrite nanocomposites not only had better biocompatibility than some classical gold nanoparticles but also exhibited unique advantages in tumor inhibition.

Manganese (Mn) nodule is one of the ubiquitous polymetallic concretions and mainly consists of Mn − Fe oxi-hydroxide precipitations. A primary oxidation of Mn(II) to MnO2, in which microorganisms may play important roles, is followed by agglomeration of MnO2 into nodules. Celeribater manganoxidans DY25T, belonging to family Rhodobacteraceae, has ability to catalyze the formation of MnO2 [ 1 ]. The concentration of MnO2 formed by harvested cells reached 7.08 μM after suspended in 10 mM HEPES (pH 7.5). Genomic and physiological characteristics of strain DY25T provided a better understanding of its Mn-oxidizing mechanism. Fifteen genes (including four multicopper oxidases) may be involved in Mn(II)-oxidation, whereas only three of them can promote this process. Sulfur-oxidizing activity was detected, which may be associated with manganese oxidation. Genes involved in import and export of primary elemental ingredients (C, N, P and S) and metallic elements (e.g. Mn) were discovered, demonstrating its potential roles in the biogeochemical cycle.

A strategy for the synthesis of cis-hydrocarbazole with a C3 quaternary carbon center has been developed through nickel/Lewis acid dual-catalyzed arylcyanation. A wide array of cis-hydrocarbazoles was accessed with high diastereoselectivities and atom economies in a good yield. The rich chemistry of the installed nitrile group was demonstrated in the preparation of tryptamine- and tryptophol-derived cis-hydrocarbazoles.

With the aggravation of the energy crisis, increasing attention has been paid to electrocatalytic technology for renewable energy devices. In particular, the research on catalysts towards the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) has become more urgent, and the development of multifunctional electrocatalysts has become a research trend. Here we report the synthesis of waxberry-like cobalt-nickel oxide/S,N-codoped carbon hollow nanocomposites as trifunctional catalysts. Uniform cobalt-nickel glycerate solid spheres are first synthesized as the precursor and subsequently chemically transformed into cobalt-nickel oxide/S,N-codoped carbon hollow nanospheres. Benefiting from the synergistic coupling of cobalt-nickel oxide and S,N-codoped carbon nanocomposites, hierarchical porosity and hollow structure, the cobalt-nickel oxide/S,N-codoped carbon nanohybrids exhibit superior trifunctional electrocatalytic activity and durability towards OER, ORR, and HER in alkaline media.

Understanding how to modify the intrinsic physical or chemical properties of precious metals to improve their electrocatalytic performance is crucial to the design of active and robust catalysts with high catalytic performance and low quantities. This report describes how to modify the intrinsic physical properties (lattice strain, high active facets and d-band center) of platinum–palladium alloy nanotetrahedra (PtnPd100−n NTDs) through simple tuning of the alloy composition, resulting in a higher electrocatalytic performance than pure platinum. The results show that PtnPd100−n NTDs possess dominant (111) facets and have a tuneable composition and reveal that lattice shrinking and expansion are tuned by the alloy composition, which is confirmed by TEM and X-ray diffraction, and also change the activity of methanol and ethanol electrooxidation. Interestingly, Pt62Pd38/C NTDs with lattice shrinking have the optimal composition with maximum mass activity (1.21 A mgPt+Pd−1 and 0.66 A mgPt+Pd−1) toward the MOR and EOR, respectively, which is also supported by DFT. XPS analysis and electrocatalytic experiments reveal that the combination of alloy-induced band structure engineering and lattice strain modulation weakens the adsorption of poisoning species and fundamentally improves the catalytic activity. The PtnPd100−n/C NTDs exhibit high catalytic activity and stability for the methanol and ethanol electrooxidation reaction. These findings will provide a new path for designing robust and active nanoalloy catalysts with lattice mismatch and dominant active facets for direct alcohol fuel cell applications.

The HIV reservoir size in target CD4+ T cells during primary infection remains unknown. Here, we sorted peripheral and intestinal CD4+ T cells and quantified the levels of cell-associated SIV RNA and DNA in rhesus macaques within days of SIVmac251 inoculation. As a major target cell of HIV/SIV, CD4+ T cells in both tissues contained a large amount of SIV RNA and DNA at day 8–13 post-SIV infection, in which productive SIV RNA highly correlated with the levels of cell-associated SIV DNA. Memory CD4+ T cells had much higher viral RNA and DNA than naïve subsets, yet memory CD4+ T cells co-expressing CCR5 had no significant reservoir size compared with those that were CCR5-negative in blood and intestine. Collectively, memory CD4+ T cells appear to be the major targets for primary infection, and viral reservoirs are equally distributed in systemic and lymphoid compartments in acutely SIV-infected macaques.

The osmolyte dimethylsulfoniopropionate (DMSP) is produced in petagram amounts by marine microorganisms. Estuaries provide natural gradients in salinity and nutrients, factors known to regulate DMSP production; yet there have been no molecular studies of DMSP production and cycling across these gradients. Here, we study the abundance, distribution and transcription of key DMSP synthesis (e.g. dsyB and mmtN) and catabolic (e.g. dddP and dmdA) genes along the salinity gradient of the Changjiang Estuary. DMSP levels did not correlate with Chl a across the salinity gradient. In contrast, DMSP concentration, abundance of bacterial DMSP producers and their dsyB and mmtN transcripts were lowest in the freshwater samples and increased abruptly with salinity in the transitional and seawater samples. Metagenomics analysis suggests bacterial DMSP-producers were more abundant than their algal equivalents and were more prominent in summer than winter samples. Bacterial DMSP catabolic genes and their transcripts followed the same trend of being greatly enhanced in transitional and seawater samples with higher DMSP levels than freshwater samples. DMSP cleavage was likely the dominant catabolic pathway, with DMSP lyase genes being ~4.3-fold more abundant than the demethylase gene dmdA. This is an exemplar study for future research on microbial DMSP cycling in estuary environments.

In this study, we aimed to achieve an efficient repair of damaged skeletal muscles using polyvinyl alcohol (PVA) soluble microneedle patches (MNP) loaded with carbonized wormwood and prostaglandin E2 (inflammatory factors). The introduction of carbonized wormwood imparted the MNP with near-infrared light heating characteristics that improved the efficiency of prostaglandin E2 delivery while also promoting circulation in the damaged muscle area. Our experimental results showed that, compared with the classical moxibustion treatment, the system could more quickly restore muscle strength and the cross-sectional area of muscle bundle fibers in a mouse model of muscular injury. In addition, it could also successfully induce the proliferation and differentiation of muscle stem cells to effectively repair injured muscle tissues. Above all, this light-controlled photothermal MN (microneedle) drug-delivery system avoided the common problems of traditional moxibustion such as large levels of smoke, slow efficacy and risk of scalding. Collectively, we put forward a safe, accurate and efficient approach for skeletal muscle damage treatment using carbonized wormwood.

Current evidence shows that oxidative stress plays an essential role in the pathogenesis and progression of inflammatory bowel disease (IBD). TotalROX (λabs/λem = 425/525 nm) is a ratiometric probe with high detection sensitivity and a superior capacity to monitor total cellular oxidative capacity. Herein, we investigated the potential of combining totalROX with an oral nanoparticle delivery system to detect the degree of colitis. This detection system also featured pH-responsive Eudragit S100, hyaluronic acid with high affinity to the CD44 receptor, and chitosan, and demonstrated improved loading efficiency and stability. An experimental mouse model of experimental colitis was induced by dextran sodium sulfate do that we could investigate the ability of our nanoparticles to target the colon and determine the degree of inflammation. We also determined and validated the positive correlation between the fluorescence intensity of the detection product (Ox670, λabs/λem = 650/675 nm) and myeloperoxidase activity (R2 = 0.97) and the histopathological score (R2 = 0.98). TotalROX had significant ability to measure reactive oxygen species (ROS) produced by cells under inflammatory conditions, as confirmed by in vitro experiments with Caco-2 cells. Collectively, the data generated demonstrate that when loaded with totalROX, these functional nanoparticles are promising tools for cellular imaging after oral administration. This is the first description of a ROS-responsive fluorescent probe to evaluate the degree of colitis in experimental animal models and provides a promising approach for the diagnosis of inflammation in IBD with fluorescence-guided colonoscopy.

Although the photochemical behavior of surface water and its effects on pollutant transformation have been studied extensively in recent years, the photochemistry of paddy water remains largely unknown. In this study, we examined the photochemical processes involving paddy water samples collected at four different cultivation stages of rice. Triplet dissolved organic matter (3DOM*), singlet oxygen (1O2), and hydroxyl radicals (•OH) were found to be the dominant reactive intermediates (RIs), and their apparent quantum yields and steady-state concentrations were quantified. Compared with the typical surface water, quantum yields of 3DOM* and •OH were comparable, while quantum yields of 1O2 were about 2.4-6.7 times higher than those of surface water. Fluorescence emission-excitation matrix (EEM) spectra, Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), and statistical analysis revealed that DOM properties and nitrite concentration were the main factor influencing RIs generation. The results suggest that DOM with lower molecular weight and humification extent generated more RIs, and nitrite contributed to 23.9%–100% of •OH generation. EEM and FTICR-MS data showed that DOM with more saturated and less aromatic formulas could produce more 3DOM* under the irradiation, while the polyphenolic components of DOM inhibited the formation of RIs. Moreover, RIs significantly enhanced arsenite (As(III)) oxidation with oxidation rate increased by 1.8–4.1 times in paddy water, and •OH and 3DOM* were the main RIs responsible for As(III) oxidation. This study provides new insight into the pathways of arsenite abiotic transformation in paddy soil and water.

Osteoporosis is one of the most common diseases affecting bone metabolism. Nitric oxide (NO), an endogenous gas molecule involved in osteogenesis, can effectively promote the proliferation and differentiation of osteoblasts. Although exogenous NO can reverse osteoporosis to a certain extent, the transitory half-life and short diffusion radius of NO severely limit its application. In this work, a gas generation nanoplatform of NO with bone targeting property (UCPA) is developed based on the upconversion nanoparticles (UCNPs) that can convert 808 nm near-infrared (NIR) light into UV/blue light, and further stimulate the NO donor (BNN) to release NO. With an adjustment of the output power of the 808 nm NIR, the amount of released NO can be precisely controlled. Bothiin vitro/iandiin vivo/iexperiments demonstrate the favorable affinity of UCPA to bone due to the modification of alendronate; thus, it can directly release NO in bone and reverse osteoporosis. In addition, the cellular uptake of nanocomposites and intracellular NO release can be observed in preosteoblasts, thereby promoting their differentiation efficiently.

DNA methyltransferases may function as important biomarkers of cancers and genetic diseases. Herein, we develop a dye-sensitized and gold plasmon-enhanced cathodic photoelectrochemical (PEC) biosensor on the basis of p-type covalent organic polymers (COPs) for the signal-on measurement of M.SssI methyltransferase (M.SssI MTase). The cathodic PEC biosensor is constructed by the in situ growth of p-type COP films onto a glass coated with indium tin oxide and the subsequent assembly of biotin- and HS-labeled double-stranded DNA (dsDNA) probes onto the COP film via biotin-streptavidin interaction. The dsDNA probe contains the recognition sequence of M.SssI MTase. The COP thin films possess a porous ultrathin nanosheet structure with abundant active sites, facilitating the generation of a high photocurrent compared with the hydrothermally synthesized ones. The presence of DNA methyltransferases can prevent the digestion of restriction endonuclease HpaII, consequently inducing the introduction of gold nanoparticles (AuNPs) to the dsDNA probes via the S-Au bond and the intercalation of rhodamine B (RhB) into the DNA grooves to produce a high photocurrent due to the dye-photosensitized enhancement and AuNP-mediated surface plasmon resonance. However, in the absence of M.SssI MTase, HpaII digests the dsDNA probes, and neither AuNPs nor RhB can be introduced onto the electrode surface, leading to a low photocurrent. This cathodic PEC biosensor possesses high sensitivity and good selectivity, and it can screen the inhibitors and detect M.SssI MTase in serum as well.

Herein, we synthesize the thiophene tetraphenylethene-based conjugated microporous polymer (ThT-CMP) using the tetraphenylethylene derivative [i.e., 1,1,2,2-tetrakis(4-bromophenyl)ethane (TPBE)] and 2,5-thiophenediboronic acid as the precursors. The aggregation of TPBE in the ThT-CMP can induce a strong dual-band bipolar electrochemiluminescence (AIECL) emission at 554 nm (anodic) and 559 nm (cathodic) with tri-n-propylamine (TPrA) and S2O82- as the coreactants, respectively. The anodic and cathodic ECL efficiencies are measured to be 11.49 and 3.82% with respect to the standard of the Ru(bpy)32+/TPrA system, respectively. We further develop a dipolar ECL sensor to sensitively detect rhodamine B (RhB) based on resonance energy transfer. This ECL sensor possesses a large dynamic range and high sensitivity. This research provides a new avenue of designing organic structures with the characteristic of bipolar AIECL for the development of luminescent devices.

The influence of the processing conditions on the interfacial and electrical properties of the high-k/SiGe gate stacks based on ozone oxidation is investigated. Detailed analyses of the relationship between the interface chemical structures and the corresponding electrical properties, as a function of oxidation time, reveal that the change in the distribution of the Ge atoms is the dominant factor to achieve superior electrical properties. In addition, the increase in the ratio of Si 4+ to Si 3+ of the oxide interlayer can help decrease the interface trap densities. These results provide us an important passivation route for the high-k/SiGe interface based on ozone oxidation, which is to explore an oxidation method that can realize an ultrathin interlayer including as much Si 4+ component as possible over a long oxidation time.

Orlistat is an FDA-approved over-the-counter drug to treat obesity through the inhibition of lipase activity. Macrophages, which express high levels of lipoprotein lipase (LPL), are important phagocytes in the innate immune system. Our previous studies indicated that environmentally relevant concentrations of arsenite (As

This study describes a promising strategy coupled heteropolyacids and enzyme to saccharification of raw bamboo leaves biomass. High yield of saccharides is scalable using this coupling technology. The phosphotungstic acid (PTA) and xylanase are adopted in this catalytic system and performed to produce xylose and polysaccharides with potential high activity. 317.7 mg/g of total monosaccharides and 170.0 mg/g polysaccharides (48.7% yield of total saccharides) are achieved by H3PW12O40 under 150 °C for 2.0 h successively coupled 200 μL xylanase digesting for 7.0 h. The coupling strategy of heteropolyacids and enzyme could promote respective advantages because Bronsted acid sites in PTA could regularly degrade the hemicellulose and cellulose to generate smaller molecules and successively expose more reactive sites to enzymes. DPPH and ABTS radicals scavenging activities and reducing power investigations further prove the polysaccharides exhibit strong antioxidant activity compared to the concentrated vitamin C. This method may aid in fast production of monosaccharides and bio-active polysaccharides for both of healthy medicine and food industry.

A double cyclization strategy was developed to construct the common tetracyclic core of calyciphylline B-type alkaloids. Key features of the synthesis included asymmetric Evans alkylation, ring-closing metathesis reaction, intermolecular amidation, intramolecular aza-Michael addition, and aldol condensation reactions. This strategy may be applied to the total syntheses of this type of natural product.

As a thin material with a lamellar structure, graphene oxide (GO) may extend the already superior tribological properties of ferrofluids. For this purpose, magnetic Fe3O4 nanoparticles were fabricated on the GO surface with different compositions by the co-precipitation method. Then, the GO-Fe3O4 nanohybrids coated with a surfactant were dispersed in paraffin oil to achieve stable ferrofluids. The tribological results demonstrated that compared with paraffin oil, friction coefficient reduced by 19.4% and 25.8–35.5% when lubricated with ferrofluids containing 0.5 wt% of Fe3O4 nanoparticle and GO-Fe3O4 nanohybrids, respectively. The results also indicated that nanohybrids with the higher content of GO exhibited better lubrication behaviors. It can be concluded that the introduction of GO helps to further promote the lubricity of traditional Fe3O4-based ferrofluids. The excellent tribological behaviors of GO-Fe3O4-based ferrofluids were ascribed to the triboflim and the synergistic effects of GO and Fe3O4.

With the advantages of wide distribution, fast growth, and broad metabolic spectrum to organic carbon compounds, Vibrio may play an important role in organic carbon cycling. However, the ecological roles of Vibrio in many marine environments have not been explored. Here, the world’s deepest ‘blue hole’, the Sansha Yongle Blue Hole (SYBH) in the South China Sea, which is a geographically semi-enclosed environment featuring unique chemical characters, was investigated. The abundance, diversity and carbon source utilization capability of Vibrio were studied by quantification and high-throughput sequencing of Vibrio specific 16S rRNA genes and cultivation methods. The abundance of Vibrio in water column of the SYBH ranged from 3.78 × 104 to 7.35 × 106 16S rRNA gene copies L−1. Free-living Vibrio was more abundant than particle-associated Vibrio (~ 1.20 × 106 versus~ 2.68 × 105 gene copies L−1), indicating that Vibrio prefers a free-living life style. The Vibrio assemblages showed clear vertical stratification and could be divided into three groups: aerobic-transition, middle anaerobic and bottom anaerobic zones. Dissolved oxygen (DO), temperature, pH and salinity were the main environmental factors affecting the abundance and community composition. Cultivated Vibrio demonstrated a degrading capability to various macromolecular substrates, including starch, Tween 20/40/80, DNA, gelatin, alginate, casein, chitin, lecithin, κ-carrageenan, mannan, xylan and hyaluronic acid. This suggests that Vibrio could produce a variety of highly active extracellular enzymes. Our study provides new insights into the distribution pattern and possible role in carbon cycle of Vibrio in the unique environment of a ‘blue hole’.

Black fungus derived carbonaceous aerogel (BFA) was prepared via a convenient and energy efficient ultrasonic disposal process. The adsorption experiments of atmospheric pollutants demonstrated the superior adsorbability of black fungus aerogel on PM2.5, PM10 and formaldehyde. More importantly, black fungus aerogel (BFA) exhibited intriguing double-faced properties. We explored properties of each side of the black fungus from three aspects: water contact angle measurements, liquid selective absorption capacity and air pollutant adsorption abilities. The subsequent modification of ZnO nanosheets endowed the prepared black fungus aerogel with several valuable properties, including broad-spectrum antibacterial capability and high-efficient adsorption ability. These valuable characters implied the BFA to be a promising bacteriostat and cleaner for air and water pollution treatment.

In this study, the photochemistry of carbon dots (CDs) and their effects on pollutant transformation were systematically examined. Diethyl phthalate (DEP) degradation was strongly enhanced by CDs under UV light, with the observed reaction rate constant ( k

C-C chemokine receptor 5 (CCR5) plays an essential role in HIV pathogenesis as the major coreceptor on CD4+ T cells used by HIV, yet the function of CCR5 on CD8 T cells is not well understood. Furthermore, the immunologic effects of the CCR5 inhibitor maraviroc (MVC), despite approval for clinical use, have not yet been well evaluated for their potential effects on cytotoxic T-cell responses. In this study, we characterized the development and function of CCR5+CD8+ T cells in rhesus macaques with or without Simian immunodeficiency virus (SIV) infection. We also investigated the effects of the CCR5 antagonist MVC on functional CCR5+CD8+ T-cell responses in vitro. The data show that CCR5+CD8+ T cells have an effector memory phenotype and increase with age in systemic and mucosal lymphoid tissues as a heterogeneous population of polyfunctional CD8 T cells. In addition, CCR5 is highly expressed on SIV gag-specific (CM9+) CD8+ T cells in SIV-infected macaques, yet CCR5+CD8+ T cells are significantly reduced in mucosal lymphoid tissues with disease progression. Furthermore, in vitro MVC treatment reduced activation and cytokine secretion of CD8+ T cells via a CCR5-independent pathway. These findings suggest that surface CCR5 protein plays an important role in differentiation and activation of CD8+ T cells. Although MVC may be helpful in reducing chronic inflammation and activation, it may also inhibit virus-specific CD8+ T-cell responses. Thus optimal use of CCR5 antagonists either alone or in combination with other drugs should be defined by further investigation.-Wang, X., Russell-Lodrigue, K. E., Ratterree, M. S., Veazey, R. S., Xu, H. Chemokine receptor CCR5 correlates with functional CD8+ T cells in SIV-infected macaques and the potential effects of maraviroc on T-cell activation.

The uptake, accumulation, and long-distance transport of organophosphate esters (OPEs) in four kinds of plants were investigated by hydroponic experiments. The uptake kinetics ( k1,root) of OPEs in plant roots were determined by the binding of OPEs with the proteins in plant roots and apoplastic sap for the hydrophobic compounds, which correlated well with the transpiration capacity of the plants for the hydrophilic compounds. However, the accumulation capacity of OPEs in plant root was controlled by the partition of OPEs to plant lipids. As a consequence, OPEs were taken up the fastest in wheat root as a result of its highest protein content but least accumulated as a result of its lowest lipid content. The translocation factor of the OPEs decreased quickly with the hydrophobicity (log Kow) increasing, suggesting that the hydrophobic OPEs were hard to translocate from roots to shoots. The hydrophilic OPEs, such as tris(2-chloroisopropyl) phosphate and tris(2-butoxyethyl) phosphate, were ambimobile in the plant xylem and phloem, suggesting that they could move to the edible parts of plants and enhanced risk to human health.

Because of the wide practical applications of soft materials, the surface contact and adhesive behaviors need to be comprehensively understood. Here, we systematically investigated the effect of bulk viscoelasticity and surface wetting on the dynamic behavior of contact and adhesion of soft polydimethylsiloxane (PDMS) surfaces. Experimental results showed that during the indentation process, the relation between loads and contact radius were close to the Johnson-Kendall-Roberts (JKR) mode, but the load-penetration curves presented a roughly linear dependence with increasing preloads transferring from the JKR to Hertz mode; the detaching process exhibited a pronounced “stick-split” behavior, where the spherical probe first stuck to the soft PDMS without decreasing the contact area, and then the crack of the contact edge opened and split, providing high adhesive forces far exceeding the JKR prediction. The introduction of liquids between the probe and soft PDMS strongly decreased the contact area, reduced the stick time, and weakened the dry adhesive strength depending on the surface tension. The internal friction induced by the segmental motion of long-chain molecules and the interfacial resistance of liquid were suggested to be responsible for these phenomena.

A concise and efficient strategy for the synthesis of the common 6,6-dimethyltricyclic[5.4.0.02,8]undecane framework of longipinane- and ent-longipinane-type sesquiterpenoids has been developed. This approach features an intramolecular Diels–Alder reaction to construct the 6/7 cis-fused ring system and a Ti(III)-mediated reductive radical cyclization reaction to access the highly strained bridged cyclobutane moiety.

Introduction Inflammation and oxidative stress are closely correlated in the pathology of cardiovascular disease. Mitochondrial cyclophilin D (CypD), the important modulator for mPTP opening, is increasingly recognized as a key regulator of cellular ROS generation. Besides, its association with cell inflammation is also being discovered. However, the effects of CypD in modulating vascular inflammatory response is unknown. We sought to investigate whether CypD deficiency attenutes vascular inflammation under physical conditions. Methods and results We adopted CypD KO mouse and their littermate controls to observe the effects of CypD deficiency on aortic mitochondrial functions and vascular inflammation. As we found in our study, we confirmed that under physical conditions, CypD deficiency enhanced mouse whole body metabolic status, increased aortic mitochondrial complex III activity and decreased mitochondrial ROS generation. Functionally, CypD deficiency also attenuated inflammatory molecules expression, including VCAM-1, IL-6 and TNF-α in mouse aorta. Conclusions Our results review that mitochondrial CypD is involved in the regulation of inflammation in aorta and provide insights that blocking mitochondrial CypD enhances vascular resistance to inflammatory injuries.

A simple, rapid, and effective colorimetric assay for the detection of uric acid (UA) has been built, using the MoS2 nanoflakes-catalyzed 3,3′,5,5′-tetramethylbenzidine (TMB)-H2O2 system. In the presence of oxygen and uricase, uric acid was oxidized specifically to produce H2O2. MoS2 nanoflakes synthesized by hydrothermal reaction could catalyze the oxidation of TMB by H2O2, and engendering the colorimetric signal. Finally, the change in the color from colorless to blue was seen with naked eye, indicating the presence or absence of UA. Under the optimized conditions, a linear relationship between the absorbance and UA concentration in the range of 0.5–100 μM (R2 = 0.996) with the limit of detection for 0.3 μM (S/N = 3). The proposed assay was successfully applied to the detection of UA in human serum with the recoveries over 94.54%. Thus, these results suggest that the UA assay–based MoS2-catalyzed TMB-H2O2 has great foreground for fast clinical diagnosis of gout without the need for advanced and costly equipment.

Environmental exposure to arsenic is known to induce immunotoxicity. Macrophages are the professional phagocytes that are important in the immune system. In this study, we utilized the macrophages derived from the THP-1 human monocyte cell line as the experimental model to study the functional suppression induced by arsenite (As+3), one of the most prevalent forms of inorganic arsenic, at environmentally-relevant concentrations. Apoptosis was observed in the THP-1 derived macrophages treated with 500 nM As+3 for 18 h. Suppression of phagocytosis was induced by 18 h As+3 treatment starting from 100 nM. Suppressive effects on the production of two pro-inflammatory cytokines, IL-1β and TNF-α, were also found with the treatment of low to moderate doses of As+3 in lipopolysaccharides-stimulated THP-1 derived macrophages. The nitric oxide production was also inhibited by As+3 treatments, which was negatively correlated with the production of superoxide. Collectively, the results from the study demonstrated that environmentally-relevant concentrations of As+3 induced cytotoxicity and suppressed the major cellular functions in THP-1 derived macrophages. The macrophages were showed to be relatively sensitive to As+3, and could be the essential target of the toxicity induced by environmental arsenic exposures.