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Stable-isotope labeling strategies are extensively used for multiplex quantitative proteomics. Hybrid-isotope labeling strategies that combine the use of isotopic mass difference labeling and isobaric tags can greatly increase sample multiplexity. In this work, we present a novel hybrid-isotope labeling approach that we termed NHS-ester tandem labeling in one pot (NETLOP). We first optimized 16-plex isobaric TMTpro labeling of lysine residues followed by 2-plex or 3-plex isotopic mTRAQ labeling of peptide N-termini, both of which with commercially available NHS-ester reactive reagents. We then demonstrated the utility of the NETLOP approach by labeling HeLa cell samples and performing proof-of-principle quantitative 32-plex and 48-plex proteomic analyses, each in a single LC-MS/MS experiment. Compared to current hybrid-isotope labeling methods, our NETLOP approach requires no sample cleanup between different labeling steps to minimize sample loss, induces no retention time shifts that compromise quantification accuracy, can be adapted to other NHS-ester isotopic labeling reagents to further increase multiplexity, and is compatible with samples from any origin in a wide array of biological and clinical proteomics applications.

The intrinsic activity of Co(OH)2 for oxygen evolution reaction (OER) may be elaborately improved through the suitable valence adjustment. Ce modification at electronic level is proved to be an efficient strategy owing to the flexible transformation of Ce3+/Ce4+. Herein, Ce0.21@Co(OH)2 with the optimized Ce doping have been fabricated to tailor the fast electron transfer for the enhanced activity and stability for OER. Firstly, the obtained core–shell structure composed of vertical loose Co(OH)2 sheets not only exposes a large number of active sites, but also provides channels for Ce doping. Secondly, the high pressure microwave with instantaneous heating can fast introduce Ce into Co(OH)2, obtaining Cex@Co(OH)2 with well dispersion and close integration. The intimated interaction between Ce and Co species may provide the “d–f electronic ladders” for accelerating electron transfer of the catalytic surface. Meanwhile, Ce promotes the formation of Co-superoxide intermediate and/or the release of oxygen, which is considered to be the rate-determining step for OER. The electrochemical measurements confirmed the low overpotential of 300 mV at 10 mA cm−2 and great stability of Ce0.21@Co(OH)2 for OER. This work demonstrates a meaningful approach to realize the tuned electronic structure through metal doping.

SUMMARY The Curie-point depth is an important magnetic parameter for studying the geological structure and thermal evolution of the lithosphere. In this study, we first apply wavelet transform to the centroid method, and compare it with the conventional Fourier spectral centroid method based on a 3-D fractal magnetization model. We find that the Fourier transform method is suitable for estimating smaller Curie-point depths (less than 20 km), whereas the wavelet transform method has better accuracy in estimating large Curie-point depths (more than 30 km). The application of both methods to the western Pacific magnetic anomalies from the Earth Magnetic Anomaly Grid of 2-arcmin resolution (EMAG2) proves their reliability and comparability. Our results show small Curie-point depths in areas with active magmatism and high heat flow, like mid-ocean ridges and island arcs of subduction zones, but large Curie-point depths in sedimentary basins and forearcs of subduction zones with low surface heat flow. We wrote our Curie-point depth inversion software CPDINV using FORTRAN language, which includes completed modules of minimum-curvature gridding, projection, wavelet and Fourier transforms, least-squares fitting and depth estimation.

First evidence of a structure in the $J/\psi{\Lambda}$ invariant mass distribution is obtained from an amplitude analysis of$\Xi_b^-{\rightarrow}J/\psi{\Lambda}K^-$ decays. The observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of $3.1\sigma$ including systematic uncertainties and look-elsewhere effect. Its mass and width are determined to be $4458.8\pm2.9^{+4.7}_{-1.1}$ MeV and $17.3\pm6.5^{+8.0}_{-5.7}$ MeV, respectively, where the quoted uncertainties are statistical and systematic. The structure is also consistent with being due to two resonances. In addition, the narrow excited $\Xi^-$ states, $\Xi(1690)^-$ and $\Xi(1820)^-$, are seen for the first time in a $\Xi^-_b$ decay, and their masses and widths are measured with improved precision. The analysis is performed using $pp$ collision data corresponding to a total integrated luminosity of 9 fb$^{-1}$, collected with the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV.

Cascade radical cyclization of N-arylacrylamides is an attractive method to prepare 3,3-disubstituted oxindoles. As the reported methods often require additives and/or photocatalysts, we herein report an additive- and photocatalyst-free deaminative strategy for their synthesis under mild conditions, enabled by photoactivation of an electron donor-acceptor (EDA) complex. DFT studies indicated that the involvement of an explicit xylene solvent molecule can greatly enhance the photoactivity of the EDA complex between N-arylacrylamides and Katritzky salts.

The 2 + 1 -dimensional elliptic Toda equation is a higher dimensional generalization of the Toda lattice and also a discrete version of the Kadomtsev-Petviashvili-1 (KP1) equation. In this paper, we derive the M -breather solution in the determinant form for the 2 + 1 -dimensional elliptic Toda equation via Bäcklund transformation and nonlinear superposition formulae. The lump solutions of the 2 + 1 -dimensional elliptic Toda equation are derived from the breather solutions through the degeneration process. Hybrid solutions composed of two line solitons and one breather/lump are constructed. By introducing the velocity resonance to the N -soliton solution, it is found that the 2 + 1 -dimensional elliptic Toda equation possesses line soliton molecules, breather-soliton molecules, and breather molecules. Based on the N -soliton solution, we also demonstrate the interactions between a soliton/breather-soliton molecule and a lump and the interaction between a soliton molecule and a breather. It is interesting to find that the KP1 equation does not possess a line soliton molecule, but its discrete version—the 2 + 1 -dimensional elliptic Toda equation—exhibits line soliton molecules.

The proportion of railway cold chain transportation in the overall cold chain logistics transportation market is relatively small in China. Freight subsidies and cold chain train operations are typically effective approaches to guide the public transit of cold chain cargo flow and grow the railway cold chain transportation market. We analyzed the cost structure of a cold chain transportation network. We established a network optimization model of the railway cold chain logistics based on a freight subsidy and designed an adaptive genetic–simulated annealing algorithm (A-SAGA). Taking the cold chain transportation between the Yangtze river delta urban agglomerations and the Chengdu–Chongqing city group as an example, we determined the optimal cold chain logistics transportation scheme using the traditional genetic algorithm and the A-SAGA. Moreover, we conducted sensitivity analysis on freight subsidies, train travel speeds, soft time windows, and carbon tax rates. The results showed that for medium- and long-distance cold chain transportation, the railway market share increased from 17.55% to 18.75% with an increase in the railway freight rate subsidy share from 0% to 30%. More cold chain goods were transported by rail when the soft time window or the carbon tax rate increased. Moreover, the railway market share increased from 17.55% to 43.75% with an increase in the train travel speed from 60 km/h to 120 km/h. Thus, compared with freight subsidy, increasing the train travel speed is a better approach to improve the competitiveness of railway cold chain logistics.

Advanced beyond-silicon electronic technology requires both channel materials and also ultralow-resistance contacts to be discovered1,2. Atomically thin two-dimensional semiconductors have great potential for realizing high-performance electronic devices1,3. However, owing to metal-induced gap states (MIGS)4–7, energy barriers at the metal–semiconductor interface—which fundamentally lead to high contact resistance and poor current-delivery capability—have constrained the improvement of two-dimensional semiconductor transistors so far2,8,9. Here we report ohmic contact between semimetallic bismuth and semiconducting monolayer transition metal dichalcogenides (TMDs) where the MIGS are sufficiently suppressed and degenerate states in the TMD are spontaneously formed in contact with bismuth. Through this approach, we achieve zero Schottky barrier height, a contact resistance of 123 ohm micrometres and an on-state current density of 1,135 microamps per micrometre on monolayer MoS2; these two values are, to the best of our knowledge, the lowest and highest yet recorded, respectively. We also demonstrate that excellent ohmic contacts can be formed on various monolayer semiconductors, including MoS2, WS2 and WSe2. Our reported contact resistances are a substantial improvement for two-dimensional semiconductors, and approach the quantum limit. This technology unveils the potential of high-performance monolayer transistors that are on par with state-of-the-art three-dimensional semiconductors, enabling further device downscaling and extending Moore’s law. Electric contacts of semimetallic bismuth on monolayer semiconductors are shown to suppress metal-induced gap states and thus have very low contact resistance and a zero Schottky barrier height.

Bentonite has been considered as a potential buffer/backfill material for construction of engineering barriers in deep geological repository for disposal of high-level nuclear waste. Anisotropy will be inevitably generated during static compaction during preparation of bentonite blocks, leading to induce possible influences on buffering function formation of the engineering barrier system and even the safety of the whole repository. In the present work, swelling deformation tests along the directions both perpendicular and parallel to the compaction plane were conducted on unsaturated compacted GMZ bentonite specimens using a self-developed lateral confined swelling test setup. Influences of initial dry density and vertical pressure on the final swelling strain and its anisotropy, as well as the mechanism of evolution of anisotropy coefficient on hydration, were analysed. Results demonstrate that the swelling time, average strain rate and final swelling strain increase with increasing initial dry density and decrease with increasing vertical pressure. Meanwhile, the swelling strain along the perpendicular direction is much higher than that along the parallel direction, exhibiting an obvious anisotropic swelling characteristic. The anisotropy coefficient is relatively large at the initial swelling stage, and then gradually decreases to be stabilised. The final anisotropy coefficient increases with initial dry density and decreases with vertical pressure.

This article describes the use of tetramethylammonium fluoride tetrahydrate (TMAF·4H2O) for the large-scale preparation of a challenging 4-fluorothiazole. Commercially available TMAF·4H2O was procu...

Spontaneous and stochastic reversal of large scale flow structure is an intriguing and crucial phenomenon in turbulent Rayleigh-Bénard type natural convection. This paper proposes a new control approach to eliminate the reversals through stabilising the corner flows using two small sidewall controllers. Based on a series of direct numerical simulations, it is shown that the control can successfully stop the growth of corner vortices and suppress the reversal of large-scale circulation, if the width of sidewall controllers installed within or near the top of corner vortices is large enough. When the controllers are located around the centre, they can easily break up the large-scale structures or even divide the single roll mode into a double-roll mode for very large widths. Moreover, the influence of sidewall controllers on the heat transport is studied. It is shown that the heat transport efficiency can be slightly enhanced or suppressed when the proper location and width are chosen. The present findings provide a new idea to control the large-scale flow structure and reversals in thermally driven convection through sidewall controlling.

In this study, we report the design and synthesis of a series of novel thiophene-arylamide compounds derived from the noncovalent decaprenylphosphoryl-β-d-ribose 2′-epimerase (DprE1) inhibitor TCA1 through a structure-based scaffold hopping strategy. Systematic optimization of the two side chains flanking the thiophene core led to new lead compounds bearing a thiophene-arylamide scaffold with potent antimycobacterial activity and low cytotoxicity. Compounds 23j, 24f, 25a, and 25b exhibited potent in vitro activity against both drug-susceptible (minimum inhibitory concentration (MIC) = 0.02–0.12 μg/mL) and drug-resistant (MIC = 0.031–0.24 μg/mL) tuberculosis strains while retaining potent DprE1 inhibition (half maximal inhibitory concentration (IC50) = 0.2–0.9 μg/mL) and good intracellular antimycobacterial activity. In addition, these compounds showed good hepatocyte stability and low inhibition of the human ether-à-go-go related gene (hERG) channel. The representative compound 25a with acceptable pharmacokinetic property demonstrated significant bactericidal activity in an acute mouse model of tuberculosis. Moreover, the molecular docking study of template compound 23j provides new insight into the discovery of novel antitubercular agents targeting DprE1.

FeOOH on the real catalytic interface for the oxygen evolution reaction (OER) is chemically unstable to dissolve in alkaline media. Herein, based on the perspective of the dynamically stable interface, we purposely design the well-dispersed nanorod arrays of CoMoO4 as a host on activated iron foam (IF) to realize the optimal redeposition of FeOOH, constructing a self-sacrificial template rich in the FeOOH surface. Notably, at long-time oxidation potential, the precatalyst FeOOH-CoMoO4 can realize MoO42- dissolution and redeposition of Co oxyhydroxides on FeOOH host simultaneously, constructing a dynamically stable Fe(Co)OOH interface. The introduction of CoOOH improves conductivity and provides synergistic effect with FeOOH to lower the energy barrier for OER and maintain long-time stability, eventually exhibiting a low overpotential of 298 mV to reach the current density of 100 mA cm-2 and high stability over 60 h. This work demonstrates the feasibility of manipulating metal dissolution-redeposition process for a dynamically stable interface.

Objective Huidouba (HDB) is a Chinese folk medicine used to treat diabetes in Sichuan Province, China. Therefore, we investigated the anti-diabetic effects of HDB and its underlying mechanisms. We hypothesized that HDB treatment could enhance glucose tolerance and insulin sensitivity, and thus prevent a hyperglycemia state. Methods To test the hypothesis, streptozotocin (STZ)-induced diabetic mice and db/db mice, widely used models of hyperglycemia and insulin-resistant diabetes, were either treated with HDB, metformin, or acarbose. Blood glucose, oral glucose tolerance test, insulin tolerance test, pancreatic histopathology and serum biochemistry were detected to assess the hypoglycemic effect of HDB. Results HDB treatments were found to show the effect in reducing glucose levels. HDB also resulted in a significant reduction in body weight and food intake in the STZ-induced diabetic mouse model. Furthermore, it significantly improved glucose and insulin tolerance in the two diabetic mouse models. Importantly, insulin, glucagon, pancreatic polypeptide, and somatostatin immunohistochemistry revealed that HDB treatment improved the function and the location of the cells in the islets compared with the other two treatments. HDB treatment resulted in significant restoration of islet function. Our results illustrated the underlying mechanism of HDB in the progression of diabetes, and HDB can be an effective agent for the treatment of diabetes. Conclusion The results of this study suggested that HDB can reduce blood glucose levels in STZ-induced hyperglycemic mice and db/db mice.

A large space antenna structure will inevitably vibrate due to the space thermal environment and maneuver actions of the satellite. Such vibration will last continuously and affect normal function ...

Trimethylated histone H3 lysine 27 (H3K27me3) is a repressive histone marker that regulates a variety of developmental processes, including those that determine flowering time. However, relatively little is known about the mechanism of how H3K27me3 is recognized to regulate transcription. Here, we identified BAH domain-containing transcriptional regulator 1 (BDT1) as an H3K27me3 reader. BDT1 is responsible for preventing flowering by suppressing the expression of flowering genes. Mutation of the H3K27me3 recognition sites in the BAH domain disrupted the binding of BDT1 to H3K27me3, leading to de-repression of H3K27me3-enriched flowering genes and an early-flowering phenotype. We also found that BDT1 interacts with a family of PHD finger-containing proteins, which we named PHD1-6, and with CPL2, a Pol II carboxyl terminal domain (CTD) phosphatase responsible for transcriptional repression. Pull-down assays showed that the PHD finger-containing proteins can enhance the binding of BDT1 to the H3K27me3 peptide. Mutations in all of the PHD genes caused increased expression of flowering genes and an early-flowering phenotype. This study suggests that the binding of BDT1 to the H3K27me3 peptide, which is enhanced by PHD proteins, is critical for preventing early flowering.

Despite several theoretically proposed two-dimensional (2D) diamond structures, experimental efforts to obtain such structures are in initial stage. Recent high-pressure experiments provided significant advancements in the field, however, expected properties of a 2D-like diamond such as sp3 content, transparency and hardness, have not been observed together in a compressed graphene system. Here, we compress few-layer graphene samples on SiO2/Si substrate in water and provide experimental evidence for the formation of a quenchable hard, transparent, sp3-containing 2D phase. Our Raman spectroscopy data indicates phase transition and a surprisingly similar critical pressure for two-, five-layer graphene and graphite in the 4–6 GPa range, as evidenced by changes in several Raman features, combined with a lack of evidence of significant pressure gradients or local non-hydrostatic stress components of the pressure medium up to ≈ 8 GPa. The new phase is transparent and hard, as evidenced from indentation marks on the SiO2 substrate, a material considerably harder than graphene systems. Furthermore, we report the lowest critical pressure ( ≈ 4 GPa) in graphite, which we attribute to the role of water in facilitating the phase transition. Theoretical calculations and experimental data indicate a novel, surface-to-bulk phase transition mechanism that gives hint of diamondene formation.

Many noble metals are efficient catalysts for oxygen reduction reaction (ORR), including silver (Ag). Among all these noble metals, Ag is the most affordable because of its relative abundance. Surface energy has been proven to play a crucial role in the catalytic process, and straining is an effective operation to raise the surface energy over electrocatalysts. In this work, sonication was utilized to induce strain in Ag nanowires (NWs) through lattice deformation. A 0.18 J/m2 improvement of the surface energy around the stacking faults area has been calculated via density functional theory. The diffusion-limiting current density was evaluated and increases by >20% (from -4.98 to -6.00 mA/cm2) after sonication straining. Meanwhile, the onset potential remains almost constant (i.e., 0.95 V vs RHE). The results show that induction of strain has a strong impact on the diffusion-limiting current density and significantly improves the ORR catalytic performance of Ag NWs.

To develop the biomimetic chemistry of [NiFe]-H2ases, we have successfully prepared 2 types of 16 biomimetic models for [NiFe]-H2ases by various synthetic methods. These models are new cationic com...

Rodents of the extant family Gliridae, commonly called dormice, are common in European faunas since the early Eocene. Here we study for the first time specimens from St-Martin-de-Castillon C (France, early Oligocene) previously reported as Gliravus aff. majori and Pseudodryomys aff. fugax. We now refer them to Butseloglis tenuis and Microdyromys misonnei. Besides the French material, new specimens from Montalban 1D (Spain, early Oligocene) are studied. They include: Butseloglis montisalbani and M. misonnei already known in the locality, but also Oligodyromys libanicus and Glirudinus aff. glirulus reported here for the first time. Previous phylogenies of the family only focused on extant taxa. Here we propose the first phylogenetic analysis of Gliridae including both extant and fossil taxa. The relationships between the taxa show several paraphylies at the generic level and suggest that the classification of the family needs a revision. Two main clades are revealed in our analysis, including most extant taxa, both of them being closely related to the Oligocene genus Microdyromys. By comparing the phylogeny to the evolution of species-richness through time, we show that glirids underwent three major diversification phases. The first diversification event involves several clades of late Eocene and early Oligocene glirids. The second diversification event involves the two main clades still represented today. They both started diversifying in the late Oligocene and led the species richness of the family to reach a peak at the end of the early Miocene. Finally, the third diversification starts in the middle Pliocene and involves mostly extant genera. These diversification phases might have been triggered by successive glaciation events that occurred in the Oligocene, Miocene and Pliocene. A potential evolutionary advantage of this family successfully facing cold climatic events could be the ability to hibernate, acquired as early as the early Oligocene.

In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few technologies tested on Taiji-1 are presented in this paper. Gravitational wave astronomy has opened the door to test general relativity and the effect of gravity in the Universe. The authors present the capabilities of an overlap between space gravitational wave detectors LISA and Taiji to constrain the Hubble constant to 0.5%, in 10 years, and what can be learned from the satellite pilot Taiji-1 launched in 2019.

This paper quantitatively studies the transient dynamic response of a semi-submersible production platform with the loss of one or several positioning mooring lines. A semi-submersible platform, production risers, and positioning mooring lines are all included in the numerical simulation. Increased motion of the semi-submersible platform, tension variation of the remaining mooring lines/risers and the risk of mooring line or riser clashing are all investigated through fully coupled time-domain analysis. Combined environmental loads are selected from irregular waves and the steady current varying from very rough to extreme sea conditions. Three dimension radiation/diffraction theories and Morison’s equation are applied to calculate first-order wave force and second-order mean drift force of floating semi-submersible platform. Nonlinear time-domain finite element methods are employed to analyze the behavior of mooring lines and risers. Results show that the failure of mooring lines seriously reduce the platform’s stability performance. The tension of the rest lines is also increased accordingly. Remaining lines which are closer to the failed lines will have larger tension increase to compensate. Line-Line distance provides practical information for the risk of clashing investigation.

An electrochemical-biosensor (EC-biosensor) microchip consisting of screen-printed electrodes and a double-layer reagent paper detection zone impregnated with amaranth is proposed for the rapid determination of microalbuminuria (MAU) in human urine samples. Under the action of an applied deposition potential, the amaranth is adsorbed on the electrode surface and the subsequent reaction between the modified surface and the MAU content in the urine sample prompts the formation of an inert layer on the electrode surface. The inert layer impedes the transfer of electrons and hence produces a drop in the response peak current, from which the MAU concentration can then be determined. The measurement results obtained for seven artificial urine samples with known MAU concentrations in the range of 0.1–40 mg/dL show that the measured response peak current is related to the MAU concentration with a determination coefficient of R2 = 0.991 in the low concentration range of 0.1–10 mg/dL and R2 = 0.996 in the high concentration range of 10–40 mg/dL. Furthermore, the detection results obtained for 82 actual chronic kidney disease (CKD) patients show an excellent agreement (R2 = 0.988) with the hospital analysis results. Overall, the results confirm that the proposed detection platform provides a convenient and reliable approach for performing sensitive point-of-care testing (POCT) of the MAU content in human urine samples.

In this paper, we present a copper(I)-catalyzed nitrile-addition/N-arylation ring-closure cascade for the synthesis of 5,11-dihydro-6H-indolo[3,2-c]quinolin-6-ones from 2-(2-bromophenyl)-N-(2-cyanophenyl)acetamides. Using CuBr and t-BuONa in dimethylformamide (DMF) as the optimal reaction conditions, the cascade reaction gave the target products, in high yields, with a good substrate scope. Application of the cascade reaction was demonstrated on the concise total syntheses of alkaloid isocryptolepine. Further optimization of the products from the cascade reaction led to 3-chloro-5,12-bis[2-(dimethylamino)ethyl]-5,12-dihydro-6H-[1,3]dioxolo[4',5':5,6]indolo[3,2-c]quinolin-6-one (2k), which exhibited the characteristic DNA topoisomerase-I inhibitory mechanism of action with potent in vitro anticancer activity. Compound 2k actively inhibited ARC-111- and SN-38-resistant HCT-116 cells and showed in vivo activity in mice bearing human HCT-116 and SJCRH30 xenografts. The interaction of 2k with the Top-DNA cleavable complex was revealed by docking simulations to guide the future optimization of 5,11-dihydro-6H-indolo[3,2-c]quinolin-6-ones as topoisomerase-I inhibitors.

Research on the damage and seepage characteristics of unloading rock with high water pressure can help to further understand the mechanism of water inrush in deep mine floor and prevent water inrush. This paper used the RFPA2D-flow finite element software to study the failure and seepage characteristics of unloading rock with high water pressure and high stress and comparatively analyzed the failure modes and seepage characteristics of unloading rock with and without water pressure. The effects of different water pressure differences on the failure of unloading rock and the law of seepage were investigated by analyzing the change of acoustic emission and permeability coefficient with stress. The results showed that the unloading rock without water pressure was brittle failure, and the initial damage of the unloading model with water pressure was earlier than that of the model without water pressure and showed greater brittleness, and its cracks first break through at the bottom of the sample with higher osmotic pressure. With the increase in unloading, the permeability of rock increased gradually until it appeared an abrupt change. The failure mode and permeability law of the rock with different water pressure differences were basically the same, but the greater the pressure difference, the smaller the effective unloading capacity when the permeability coefficient changes suddenly, and the greater the possibility of water inrush in the rock.

The development of a portable sensor for on-site sensing of 2, 4, 6-trinitrotoluene (TNT) and other nitro aromatics (NAs) is still needed to strengthen environmental protection and public security. Herein, we report the fabrication of fluorescent few-layered MnO₂ nanosheets (FL-MnO₂ NSs) via N,N-dimethyl formamide-mediated ultrasonication and hydrothermal treatment. Electron and spectroscopy studies demonstrate that the modification of the FL-MnO₂ NSs (named as PEI-FL-MnO₂ NSs) with amine-rich polyethyleneimine (PEI) produced planar, β-phase, well-crystalline, and positively charged nanosheets. This PEI-related surface modification not only improves the quantum yield of the FL-MnO₂ NSs from 7.6 to 13.2% but also provides multiple binding sites with nitro groups of NAs. It was found that the presence of TNT, as an example of NAs, efficiently quenched the fluorescence of the PEI-FL-MnO₂ NSs due to the formation of Meisenheimer complexes through the efficient adsorption process. In comparison to PEI-modified MnO₂ quantum dots, the PEI-FL-MnO₂ NSs exhibited relatively high sensitivity to TNT with a limit of detection of 20 pM. By depositing PEI-FL-MnO₂ NSs on a filter paper, the as-made paper sensor was capable of visualizing 10 nM TNT in drinking water and 10 μM TNT on a postal envelope through the appearance of a quenching spot under a UV lamp. Besides, the adsorbed PEI polymer enables the PEI-FL-MnO₂ NSs to electrostatically interact with citrate-capped metal nanoparticles, producing the composites for catalyzing NaBH₄-mediated reduction of NAs. Since the PEI-FL-MnO₂ NSs possess a large surface area to capture NAs and serve as an electron acceptor for BH₄–, the formed composites efficiently catalyze the reaction of NaBH₄ and NAs as compared to metal nanoparticles and PEI-FL-MnO₂ NSs alone.

Pressure has been considered as an effective technique to modulate the structural, electronic, and optical properties of transition metal dichalcogenide (TMDs) materials. Here, by performing in situ high pressure Raman, photoluminescence (PL) and absorption measurements, we systematically investigated the vibrational and electronic properties evolution of monolayer MoSe2 grown on a SiO2/Si substrate under high pressure. When the pressure increased up to 4.84 GPa, an unexpected phonon mode at 367 cm−1 appeared, which was identified as the Raman-inactive A2′′ mode and was activated under high pressure. Combined with the analysis of absorption spectroscopy, this phenomenon can be attributed to the pressure-induced wrinkle and near-resonance effects in compressed monolayer MoSe2. Subsequently, A1′ split into two peaks after 7.44 GPa, providing further distinct evidence for the pressure-induced wrinkle effect in compressed monolayer MoSe2. Moreover, this wrinkle effect can also lead to a rapid quenching of photoluminescence in monolayer MoSe2. These results suggest that the substrate plays an important role in determining the vibrational and electronic properties of compressed monolayer MoSe2, and can provide valuable information on the electronic and optoelectronic applications of monolayer MoSe2 under extreme conditions.

Transition-metal sulfides (MxSy) have attracted great interest as promising catalysts for the hydrogen evolution reaction (HER) due to their low cost. However, the formation of sulfur–hydrogen bonds on MxSy (S–Hads) severely suppresses the HER. In this paper, we report a three-dimensional nickel sulfide (Ni3S2) film supported by Ag nanorods (NRs) on Ni foam (Ni3S2–Ag/NF) as a type of electrocatalyst for the HER in alkaline media. The tight coupling between Ag and Ni3S2 creates a mass of heterojunctions. Therefore, this electrocatalyst only shows a low overpotential of 161 mV at 10 mA cm−2, as well as satisfactory stability for 10 h. Density functional theory calculations reveal that the intense electronic interactions in the heterojunctions of the Ni3S2–Ag hybrids can facilitate water adsorption and activation, improve H-adsorption and desorption on the electrocatalysts, and reduce the formation of S–Hads bonds on the catalyst surfaces. The existence of strong interactions between Ag and Ni3S2 in the electrocatalyst can facilitate both the Volmer and Heyrovsky steps of the HER and cause the Ni3S2–Ag/NF electrocatalysts to exhibit outstanding HER catalytic performance. This suitable strategy involving Ag doping may be a promising choice for developing Ni sulfide-based electrocatalysts for the HER.

The aim of the paper is to propose a groundbreaking method for the aerodynamic optimization design of the bioinspired wing with leading-edge tubercles. An emphasis on the optimization design of the spanwise waviness in the leading edge for delaying stall and increasing lift from the aerodynamic performance perspective has been laid in this study. For the conversion of the wavy configuration, the form parameterized approach using F-spline curves has been used to produce more variants of the leading-edge tubercles. Numerical investigations of flow characteristics which are performed using CFD computations have been used to validate the numerical scheme with experimental data. The combination of Non-dominated Sorting Genetic Algorithm II and Response Surface Method based Kriging Model has been adopted as the aerodynamic optimization strategy. As consequence, the three main components of the optimization process are incorporated into the establishment of the aerodynamic optimization design system for the bio-inspired airfoil with leading-edge tubercles. The four optimal airfoils respectively which increases the stall angle as well as the lift have been obtained in contrast to the smooth wing. The optimized bio-inspired design of this kind can be applied to flow-controlled devices for improving the efficiency of a particular operating mechanism.

Currently, few phosphorescent materials (PMs) possess a long phosphorescence lasting time and have potential for application in chemical sensors. Herein, we disclose that the incorporation of few-layer molybdenum disulfide quantum dots (FL-MoS2 QDs) into poly(vinyl alcohol) (PVA) matrices leads to the emission of bright green phosphorescence with a long lasting time of 3.0 s and a phosphorescence quantum yield of 20%. This enhanced phosphorescence originates from the formation of O–H⋯S hydrogen bonding networks between the rich sulfur sites of the FL-MoS2 QDs and the hydroxyl groups of the PVA molecules, which not only rigidifies the vibration modes of the FL-MoS2 QDs but also provides an oxygen barrier. Further investigations reveal that the FL-MoS2 QD/PVA composites exhibit a longer phosphorescence lasting time than N,S-doped carbon dots, few layer tungsten disulfide quantum dots, Rhodamine 6G, and Rhodamine B in PVA matrices. Since heat efficiently induced the removal of water moisture from PVA matrices, the FL-MoS2 QD/PVA composites could be implemented for phosphorescence turn-on and naked-eye detection of temperature variations ranging from 30 to 70 °C. By contrast, the carbon dot/PVA composites were incapable of sensing environmental temperature due to their weak hydrogen bonding with the hydroxyl groups of PVA matrices. Additionally, this study reveals the potential of the FL-MoS2 QD/PVA composites as an advanced security ink for anti-counterfeiting and encryption applications. The given results could open a new direction for potential application of two-dimensional quantum dots in phosphorescence-based sensors and security inks.

It is widely reported that japonica/indica hybrids (JIH) have superior grain yield over other main varietal groups such as indica hybrids (IH) under sufficient resource inputs. To date, little attention has been paid to yield performance of JIH under input-reduced practices, and whether JIH could have better grain yield performance over IH under input-reduced practices. In this study, three JIH varieties and three IH varieties were compared in grain yield and their related morpho-physiological traits under two cultivation modes, i.e., conventional high-yielding method (CHYM) and double reductions in nitrogen rate and planting density (DRNP). Our results showed that JIH had 8.3 and 13.3% higher grain yield over IH under CHYM and DRNP, respectively. The superior grain yield of JIH over IH under DRNP was mainly attributed to larger sink size and improved sink filling efficiency. Three main morpho-physiological traits were concluded for better yield performance of JIH over IH under DRNP. Firstly, JIH had the reduced unproductive tillers growth, indicated by a higher percentage of productive tillers and the percentage of effective leaf area index (LAI) to total LAI at heading stage. Secondly, a synergistic increase in biomass accumulation and harvest index were achieved of JIH, supported by higher biomass accumulation and leaf area duration during the main growth periods, and improved non-structural carbohydrate (NSC) remobilization after heading. Thirdly, JIH had an improved canopy structure, showing as higher leaf area of upper three leaves and lower light extinction coefficient. Our results suggested that improved morpho-physiological traits of JIH could lead to better grain yield performance over IH under input-reduced practices.

The dendrite morphologies of the cast nickel-based superalloy CMSX-4® (CMSX-4® is registered trademarks of the Cannon-Muskegon Corporation) and the austenitic stainless steel HP microalloy have been obtained via an automated serial-sectioning process which allows three-dimensional (3D) microstructural characterization. The dendrite arm spacing, volume fraction of segregation, and fraction of porosity have been determined. This technique not only increases the depth, scope, and level of detailed microstructural characterization but also delivers microstructural data for modeling and simulation.

To ensure the normal operation of China Railway Express, the Inland Railway Container Center Station (IRCCS) needs to replenish the freight sources outside its attraction area. The homogenization of the China Railway Express route, overlapping of attraction area and chaotic transportation organization brings about disordered competition of freight. Based on the attraction area division of the IRCCS, this paper establishes a mixed integer programming model, with minimum transportation time, transportation cost and carbon emission as target. The simulated annealing algorithm is used to solve the problem, and the Harbin Railway Container Center Station is taken as an example to determine the freight collection mode, operating route and operation frequency of China Railway Express. The results show that: The transportation costs, time and carbon emissions have different degree of influence on China Railway Express operation plan, from the largest to the smallest, carbon emissions, transportation costs, time costs. Under different objective weights, the influence on the freight collection mode and transportation route is great, while the frequency impact is small.

Detecting heat damage and eliminating the susceptibility to sensitization of wrought 5xxx series aluminum-magnesium alloys is of practical importance for the remediation of field structures. Electrical conductivity and hardness testing were employed to provide indirect evidence to assess the microstructural evolution of 5083-H116 alloys after annealing treatment at 150, 200, 250, 300, 350, 400, and 450 °C and sensitization treatment at 175 °C for 168 h. The findings indicate a strong relationship between the hardness, electrical conductivity, and degree of sensitization (DoS). This methodology can be used as a simple guide to quickly determine whether heat damage or sensitization exists.

N-heterocyclic carbenes (NHCs) are well-known as ligands and organocatalysts, but there is no recognition for their catalytic role as a stabilizer through electrostatic interaction rather than electron donation. By utilizing the electrostatic interaction, we herein describe the success of a visible-light-triggered radical-radical cross-coupling of N-alkenoxypyridinium salts and NaI, giving a variety of α-iodo ketones. Computational studies characterize the stabilization role of NHCs.

In situ (TiC + SiC) particles (5 vol.% and 10 vol.%, respectively)-reinforced FeCrCoNi high entropy alloy matrix composites were fabricated via vacuum inductive melting method, with equal volume fractions of TiC and SiC particles. X-ray diffraction, scanning electron microscope and energy diffraction spectrum were employed to analyze the microstructure and composition of the samples. The results manifested that the FeCrCoNi matrix is composed of FCC phase, and the in situ particles are homogeneously scattered in the matrix. The presence of reinforcements augmented the ultimate tensile strength from 452 to 783 MPa, and raised the yield strength from 162 to 466 MPa at room temperature, whereas the elongation to fracture was reduced from 70.6% to 28.6%. All the tensile fracture surfaces consisted of numerous tiny dimples, indicating that the composites exhibited ductile fracture. Furthermore, the enhancement of strength ascribes to a combination of thermal mismatch strengthening, load-bearing effect, grain refinement, Orowan strengthening and solid solution strengthening effect, which contribute about 58.0%, 2.4%, 12.3%, 11.1% and 16.2% to the improvement of yield tensile strength, respectively.

Tuberculosis (TB) remains a serious public health challenge, and the research and development of new anti-TB drugs is an essential component of the global strategy to eradicate TB. In this work, we discovered a conformationally constrained oxazolidinone 19c with improved anti-TB activity and safety profile through a focused lead optimization effort. Compound 19c displayed superior in vivo efficacy in a mouse TB infection model compared to linezolid and sutezolid. The druggability of compound 19c was demonstrated in a panel of assays including microsomal stability, cytotoxicity, cytochrome P450 enzyme inhibition, and pharmacokinetics in animals. Compound 19c demonstrated an excellent safety profile in a battery of safety assays, including mitochondrial protein synthesis, hERG K+, hCav1.2, and Nav1.5 channels, monoamine oxidase, and genotoxicity. In a 4 week repeated dose toxicology study in rats, 19c appeared to have less bone marrow suppression than linezolid, which has been a major liability of the oxazolidinone class.

We extend the random-walk model of Vitvitska et al. for predicting the spins of dark matter halos from their merger histories. Using updated merger rates, orbital parameter distributions, and N-body constraints we show that this model can accurately reproduce the distribution of spin parameters measured in N-body simulations when we include a weak correlation between the spins of halos and the angular momenta of infalling subhalos. We further show that this model is in approximate agreement with the correlation of the spin magnitude over time as determined from N-body simulations, while it slightly underpredicts the correlation in the direction of the spin vector measured from the same simulations. This model is useful for predicting spins from merger histories derived from non-N-body sources, thereby circumventing the need for very high resolution simulations to permit accurate measurements of spins. It may be particularly relevant to modeling systems which accumulate angular momentum from halos over time (such as galactic discs) - we show that this model makes small but significant changes in the distribution of galactic disc sizes computed using the Galacticus semi-analytic galaxy formation model., 11 pages, MNRAS accepted, comments welcome

Prevention of infection at the surgical area and outbreak of wounds are the most important and at the same time challenging tasks in clinical care. This research investigates the healing effect of laparotomy wounds after the use of bio-fabricated gold nanoparticles (Au NPs) prepared utilizing Thuja occidentalis leaf extract. Ultraviolet–visible (UV–Vis) spectroscopy and X-ray diffraction (X-RD) results confirmed the successful formation of Au NPs. High-resolution Transmission Electron Microscopy (HR-TEM) images confirmed the formation of spherical shaped Au NPs comprising of 30–50 nm particle size. Dermal fibroblasts were subjected to increased concentrations of Au NPs and their effect of cytotoxicity and synthesis of collagen was evaluated. The procedure of celiotomy was conducted on rabbits where the surgical area was exposed topically with either vehicle or once/everyday with Au NPs for about 14 days. Au NPs raised the collagen production from dermal fibroblasts and improved the expression of caspase 3 by exposure to a long period. AuNPs also showed cytotoxic impact with half-maximal inhibitory concentration (IC50) of 0.16 mg/mL. Regular treatment of surgical area with AuNPs led to higher collagen deposition with reduced microbial load and enhanced healing of wounds.

The precipitation kinetics of gamma prime in the nickel based superalloy RR1000 has been characterised after solid-solution heat treatments and isothermal aging conditions relevant to service conditions. Multi-modal precipitate dispersions are formed within the alloy. Numerical methods are presented for determining the three dimensional size of the particle populations combining information obtained from Scanning Electron microscopy and Transmission Electron microscopy. This information has been used to develop a multi-component mean-field model descriptive of precipitation kinetics. The smallest particle population increases in mean size during isothermal aging at 700 ∘C where classical mean-field models of coarsening kinetics suggest that these particles should dissolve. A phenomenological model has been proposed to capture this behaviour within a statistical formulation that is applicable to both processing and service conditions.

Polymer nanocomposites filled with one-dimensional “reelable” carbon-based nanoparticles can exhibit a high dielectric constant (e′) with a small quantity of nanoparticles. However, this kind of na...

The present study investigated the chemical composition of essential oil extracted from Elsholtzia fruticosa, and evaluated the biological activities of the essential oil and its main components ag...

ZnO:S quantum dots (QDs) were synthesized by a microwave hydrothermal method. The effects of L-cysteine (L-cys) on the crystal structure, size, morphology, band gap energy and photoluminescence (PL) properties were studied by XRD, EDS, TEM, FTIR, DRS and PL spectroscopy, respectively. The XRD results showed that all samples had a wurtzite structure ZnO crystal structure and the average crystallite size was 8.4, 5.8, and 9.2 nm for ZnO, ZnO:S and L-cys capped ZnO:S (LZOS) QDs, respectively. The EDS, HRTEM and FTIR results confirmed L-cys was capped on the surface of ZnO:S QDs. It was found that the band gap energy was 3.25, 3.29 and 3.31 eV for ZnO, ZnO:S and LZOS QDs, successively. PL spectrum of ZnO QDs showed two emission peaks in the UV and visible region, respectively. When doping S into ZnO, the intensity of the UV emission reduced, while the intensity of the visible emission dramatically increased. Also, L-cys coated obviously enhanced the PL intensity of ZnO:S QDs. This work suggested that LZOS QDs could be applied in luminescent devices.

Single-photon emitters represent a key component for many quantum technologies, from quantum communication to computation. Atomically thin two-dimensional materials are promising hosts of quantum e...

With the ever-growing need for protein-level understanding in pathological research, proteomics researchers thrive to examine detailed proteome dynamics using crucial, yet often limited, primary and clinical samples. Aside from mass spectrometer instrumentation advancement, a single-tube-based high-throughput sample processing workflow is imperative to ensure sensitive, quantitative, and reproducible protein analysis for these increasingly sophisticated studies. Leveraging the benefits of an acid-cleavable detergent, RapiGest SF Surfactant (Waters Corporation), we developed and optimized a nanoproteomic workflow that we termed Nanogram TMT Processing in One Tube (NanoTPOT). Through the assessment of proteolytic digestion, tandem mass tag (TMT) labeling, online and offline fractionation strategies, our optimized workflow effectively eliminated the need for sample desalting and enabled compatible sample processing for mass spectrometry analysis. We further applied the NanoTPOT workflow to examine cellular response to stress caused by dithiothreitol in HeLa cells, where we identified and quantified 6935 and 5474 proteins in TMT 10-plex experiments with one microgram of lysate protein and 2000 sorted HeLa cells (roughly half microgram lysate protein) in each channel, respectively. Our workflow has been proven to be an effective alternative for current nanoproteomic sample processing to minimize sample loss in biological and clinical applications.

The gray mold caused by Botrytis cinerea has a significant impact on tomato production throughout the world. Although the synthetic fungicide fludioxonil can effectively control B. cinerea, there have been several reports of resistance to this fungicide. This study indicated that all of the fludioxonil-resistant strains tested, including one field-resistant isolate and four laboratory strains, had reduced fitness relative to sensitive isolates. In addition to having reduced growth, sporulation, and pathogenicity, the resistant strains were more sensitive to osmotic stress and had significantly (P < 0.05) higher peroxidase activity. BOs1, a kinase in the high-osmolarity glycerol stress response signal transduction pathway, is believed to harbor mutations related to fludioxonil resistance. Sequence analysis of their BOs1 sequences indicated that the fludioxonil-resistant field isolate, XXtom1806, had four point mutations resulting in four amino acid changes (I365S, S531G, T565N, and T1267A) and three amino acids (I365S, S531G, and T565N) in the histidine kinases, adenylyl cyclases, methyl-accepting chemotaxis receptors, and phosphatases domain, which associated with fludioxonil binding. Similarly, two of the laboratory strains, XXtom-Lab1 and XXtom-Lab4, had three (Q846S, I1126S, and G415D) and two (P1051S and V1241M) point mutations, respectively. A third strain, XXtom-lab3, had a 52-bp insertion that included a stop codon at amino acid 256. Interestingly, the BOs1 sequence of the fourth laboratory strain, XXtom-lab5, was identical to those of the sensitive isolates, indicating that an alternative resistance mechanism exists. The study also found evidence of positive cross-resistance between fludioxonil and the dicarboximide fungicides procymidone and iprodione, but no cross-resistance was detected with any other fungicides tested, including boscalid, carbendazim, tebuconazole, and fluazinam.

Density functional theory mechanistic study of the nickel-catalyzed reductive alkyne-alkyne cyclodimerization with CH3OH/BEt3 unveils that, after forming a nickel-alkyne π complex, the reaction prefers outer-sphere proton transfer rather than the common alkyne-alkyne oxidative cyclization. The outperformance of aminophosphine ligand (L1) is attributed to its bidentate coordination that favors the proton transfer, the labile -NH2 and strong electron-donating -PPh2 arms and adequate Ni-P distance that allow the hydrogen transfer of the ethyl group of MeO-BEt3-.

The literature on microcredit programs has largely focused on positive socioeconomic outcomes and low accessibility issues in farming areas and has provided less insight into the effects of easily acquired microcredit in pastoral areas. Using a case study approach, and econometric models, this paper addresses this gap by examining why and how easily acquired microcredit loans in Inner Mongolian pastoral areas increase the risk to the financial security of households or livelihood risk. Results show that existing microcredit programs increase livelihood risk because loan and repayment requirements do not align with the husbandry production cycle of contemporary Inner Mongolian pastoralists. This misalignment forces pastoralists to borrow from usurers to repay bank loans. Furthermore, households that need to borrow from usurers typically own smaller numbers of livestock and are less likely to be able to repay the usurers by selling animals. Instead, they tend to increase their bank loans in the coming year to repay the previous year’s debt, trapping them in a vicious and ultimately impoverishing circle of annual loans they cannot fully pay back, and feeding increasing debt. We suggest that microcredit programs in semiarid areas should be in sync with the local production cycle and recognize environmental constraints that cause high variation in production seasonally and year to year. Our results supplement previous findings on microcredit applications and are particularly pertinent for other semiarid areas of the world. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13280-021-01586-y) contains supplementary material, which is available to authorized users.

The first observation of the Ω b - → Ξ c + K - π - decay is reported using p p collision data at center of mass energies of 7, 8, and 13 TeV collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb - 1 . Four excited Ω c 0 baryons are observed in the Ξ c + K - mass projection of the Ω b - → Ξ c + K - π - decays with the significance of each exceeding five standard deviations. They coincide with the states previously observed in prompt p p and e + e - production. Relative production rates, masses, and natural widths of the states are measured, and a test of spin hypotheses is performed. Moreover, the branching ratio of Ω b - → Ξ c + K - π - is measured relative to the Ω b - → Ω c 0 π - decay mode and a precise measurement of the Ω b - mass of 6044.3 ± 1.2 ± 1. 1 - 0.22 + 0.19 MeV is obtained.

Correction for ‘Engineering Cu2−xS-conjugated upconverting nanocomposites for NIR-II light-induced enhanced chemodynamic/photothermal therapy of cancer’ by Kaimin Du et al., J. Mater. Chem. B, 2021, DOI: 10.1039/d1tb00337b.