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Photophysical properties of organic and organometallic luminophors are closely related with their molecular packings, enabling the exploitation of stimuli-responsive functional luminescent molecules. Mechanochromic molecules, which can change their luminescence characteristics after mechanical stimulus, have received an increasing interest due to their promising applications in multifunctional sensors and molecular switches. During the past two decades, the development of gold(I) chemistry has been attracting the attention of plenty of researchers. Indeed, a variety of gold(I) complexes with fascinating photophysical behaviors have been discovered. This review focuses on the research progress in the different types of mechanoluminochromic gold(I) complexes, including mono-, bi- and multi-nuclear gold(I) systems. Their interesting luminescence behaviors of these gold(I)-containing luminogens upon mechanical stimulus and the proposed mechanisms of their observed mechanochromic luminescence are summarized systematacially. Moreover, this review will put forward an outlook about the possible opportunities and challenges in this significative scientific field.

Background Herbs are an important part of the forest ecosystem, and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances. Based on the near-mature secondary coniferous and broad-leaved mixed forest in Jilin Province Forestry Experimental Zone, this study analyzed seasonal changes of species diversity and biomass of the understory herb layer after different intensities of thinning. Results The results showed that although the composition of herbaceous species and the ranking of importance values were affected by thinning intensity, they were mainly determined by seasonal changes. Across the entire growing season, the species with the highest importance values in thinning treatments included Carex pilosa, Aegopodium alpestre, Meehania urticifolia, and Filipendula palmata, which dominated the herb layer of the coniferous and broad-leaved mixed forest. The number of species, Margalef index, Shannon-Wiener index and Simpson index all had their highest values in May, and gradually decreased with months. Pielou index was roughly inverted “N” throughout the growing season. Thinning did not increase the species diversity. Thinning can promote the total biomass, above- and below-ground biomass. The number of plants per unit area and coverage were related to the total biomass, above- and below-ground biomass. The average height had a significantly positive correlation with herb biomass in May but not in July. However, it exerted a significantly negative correlation with herb biomass in September. The biomass in the same month increased with increasing thinning intensity. Total herb biomass, above- and below-ground biomass showed positive correlations with Shannon-Winner index, Simpson index and Pielou evenness index in May. Conclusions Thinning mainly changed the light environment in the forest, which would improve the plant diversity and biomass of herb layer in a short time. And different thinning intensity had different effects on the diversity of understory herb layer. The findings provide theoretical basis and reference for reasonable thinning and tending in coniferous and broad-leaved mixed forests.

It is crucial for emergency responders to makes a quick and accurate prediction of toxic chemical dispersions, which can lead to massive injuries and casualties. In this study, a toxic dispersion database is constructed by PHAST simulations, which consist of 30,022 toxic release scenarios of 19 chemicals. A quantitative consequence prediction model is then developed based on this database to efficiently and accurately predict dispersion downwind distances. Random forest, gradient boosting, and deep neural network algorithms are implemented and compared to find the best performing method for the model construction. The deep neural network is found to have the highest accuracy with the test set R2 higher than 0.994 and RMSE less than 0.1 for all key dispersion ranges. The developed toxic dispersion prediction models can be used to quickly generate instant toxic dispersion range estimations for any toxic chemicals at much lower computational costs.

In the present work, a SiO2@PAA catalyst for NaBH4 methanolysis composed of silica nanoparticles modified with poly(acrylic acid) has been developed. The morphology and composition of the prepared SiO2@PAA catalyst were analyzed with transmission electron microscopy, Fourier transform-infrared spectroscopy, x-ray photoelectron spectroscopy and thermogravimetric analysis. This catalyst showed excellent catalytic performance for methanolysis of NaBH4. The NaBH4 methanolysis reaction catalyzed by SiO2@PAA showed an average hydrogen generation rate 5.5 times as high as the reaction catalyzed by unmodified SiO2 and 10.6 times as high as the uncatalyzed reaction, respectively. The activation energy for methanolysis of NaBH4 catalyzed by this SiO2@PAA catalyst was 24.03 kJ/mol. Moreover, although the catalytic activity of SiO2@PAA catalyst partially lost after being used, it could be restored after being regenerated by washing with diluted hydrochloric acid solution.

This paper deals with the fault detection of a pneumatic control valve using canonical variate analysis (CVA). CVA can find the optimal linear combinations of p-window and f-window data, so that the correlation between these combinations can be maximized. Based on CVA, the p-window data is considered by traditional hotelling T2 statistic and squared prediction error (SPE) indicators, the corresponding fault detection rates (FDR) are low. In order to improve the FDR, a detection indicator based on SMD (square of the Mahalanobis distance) of the residual is proposed in this paper. The proposed indicator considers not only the information in the p-window data, but also that of the f-window data, which can improve the FDRs. The proposed techniques have been validated using a Development and Application of Methods for Actuator Diagnosis in Industrial Control Systems (DAMADICS) benchmark. It concludes that 14 out of the 19 faults can be successfully detected using the proposed method (CVA-SMD). Simulation results have shown that the CVA-SMD can improve the FDR compared with existing CVA-T2 and CVA-SPE methods. Experiments based on real-world data have also demonstrated that the CVA-SMD has better performance than existing PCA-T2, PCA-SPE, PCA-SMD, CVA-T2 and CVA-SPE methods.

Plate bending-related normal faults (i.e. bend-faults) develop at the outer trench-slope of the oceanic plate incoming into the subduction zone. Numerous geophysical studies and numerical simulations suggest that bend-faults play a key role by providing pathways for seawater to flow into the oceanic crust and the upper mantle, thereby promoting hydration of the oceanic plate. However, deep penetration of seawater along bend-faults remains controversial because fluids that have percolated down into the mantle are difficult to detect. This report presents anomalously high helium isotope (3He/4He) ratios in sediment pore water and seismic reflection data which suggest fluid infiltration into the upper mantle and subsequent outflow through bend-faults across the outer slope of the Japan trench. The 3He/4He and 4He/20Ne ratios at sites near-trench bend-faults, which are close to the isotopic ratios of bottom seawater, are almost constant with depth, supporting local seawater inflow. Our findings provide the first reported evidence for a potentially large-scale active hydrothermal circulation system through bend-faults across the Moho (crust-mantle boundary) in and out of the oceanic lithospheric mantle.

Gas-responsive nanochannels have great relevance for applications in many fields. Inspired by CO2-sensitive ion channels, herein we present an approach for designing solid-state nanochannels that allow controlled regulation of ion transport in response to alternate CO2/N2 stimuli. The pillar[5]arene (P5N) bearing diethylamine groups can convert into the water-soluble host P5C, containing cationic tertiary ammonium salt groups after absorbing CO2. Subsequently, the nanochannel walls are tailored using P5N-based host-guest chemistry. The ion transport rate of K+ in the P5N nanochannels under CO2 was 1.66 × 10-4 mol h-1 m-2, whereas that under N2 was 7.98 × 10-4 mol h-1 m-2. Notably, there was no significant change to the ion current after eight cycles, which may indicate the stability and repeatability of CO2-activated ion nanochannels. It is speculated that the difference in ion conductance resulted from the change in wettability and surface charge within the nanochannels in response to the gas stimuli. Achieving CO2-activated ion transport in solid-state nanochannels opens new avenues for biomimetic nanopore systems and advanced separation processes.

A well-fitting bra provides adequate and exceptional support of the breasts and the desirable body shape for the wearer but would not exert excessive pressure onto the breasts. Among the different design features of bras, the materials selected for the bra cups are a key element for enhancing breast support and improving the perceived comfort. This paper proposes a subject-specific model based on numerical simulation to investigate the influence of different types of bra cup materials on the shape of the breasts and amount of pressure on the breasts. The study comprises three phases. The first phase is the development of a subject-specific contact model and simulation of the bra-wearing process. The second phase is the construction and analysis of three models with different bra cup materials (knitted, woven and foam) to compare their shaping effects on the breasts and the corresponding amount of applied contact pressure. The third phase uses the validated numerical model to simulate the use of a series of virtual bra cup materials, their impact on the shape of the breasts, and the associated bra pressure. It is found that a stiffer fabric has a better performance in reshaping the breasts and reducing the amount of pressure from the straps onto the neck for a halter-neck bra but distributes a higher amount of pressure at the bottom part of the breasts. An overall better performance of reshaping the breasts is achieved by increasing the tensile strength of the bra cup material. Nevertheless, the small change in the shaping effects can be negligible after the Young’s modulus reaches about 1.5 MPa. Among the four measured variables, it is more useful to measure the gathering of the breasts and depth of cleavage than the lifting of the breasts to determine the amount of breast deformation caused by a bra. The newly developed finite element model for contact analysis in this study provides a better understanding on the interactive process between the breasts and the bra by predicting the deformation within a variance of 6.8 % in comparison to the experimental results of the contact pressure with the same trend and magnitude. Numerical simulations can therefore facilitate decisions on the type of fabric used for bra designs that provide optimal fabric pressure and other stretchable apparel products that take both the shaping effect and wear comfort into consideration.

Indoleamine 2,3-dioxygenase (IDO), an immune checkpoint protein, can cause the depletion of tryptophan (Trp) and accumulation of its metabolite of kynurenine (Kyn) in cancer cells, and generates the immunosuppressive microenvironment that supports tumor cell growth. A novel immunoregulatory prodrug micelle based on polyethylene glycol-derivatized an IDO-selective inhibitor of 1-methyltryptophan (1-MT), PEG-Fmoc-1-MT, was developed for inhibiting the IDO activity of the conversion of Trp to Kyn in tumor microenvironments. To investigate the 1-MT distribution and Trp/Kyn ratios in mice tumors with PEG-Fmoc-1-MT prodrug micelles treatment, a HPLC–MS/MS method for simultaneous determination of 1-MT and IDO biomakers of Trp and Kyn in mouse tumors was developed and validated. Triple-quadrupole mass spectrometry with positive electrospray ionization as source ionization in multiple reaction monitoring at m/z 219.0 → 160.1, 205.0 → 118.2, 209.0 → 146.1 and 249.3 → 148.3 was used for determination of 1-MT, Trp, Kyn and matrine (internal standard). The method demonstrated good linearity at the concentrations ranging from 10 to 10,000 ng/mL and lower limits of quantitation of 1 ng/mL for 1-MT, Trp and Kyn, respectively. The validated method was successfully applied to 1-MT tumor biodistribution and Trp/Kyn ratio studies in 4T1 tumor bearing mice i.v. with PEG-Fmoc-1-MT prodrug micelles. The mice tumors with PEG-Fmoc-1-MT prodrug micelles treatment exhibited higher 1-MT accumulation and lower Trp/Kyn ratio, in comparison with those of mice with 1-MT solution treatment. The developed PEG-Fmoc-1-MT prodrug micelles could be a promising IDO immunoregulatory prodrug micelles for cancer immunotherapy.

In the present research work, near infrared (NIR) spectroscopy coupled with chemometric algorithms such as partial least-squares (PLS) regression and some effective variable selection algorithms (synergy interval-PLS (Si-PLS), Backward interval-PLS (Bi-PLS), and genetic algorithm-PLS (GA-PLS)) were used for the quantification of antioxidant properties of peanut seed samples including, amongst others, total phenolic content, total flavanoid content and total antioxidant capacity. The developed models were assessed using coefficients of determination for the calibration (R2) and prediction (r2); root mean standard error of cross-validation, RMSECV; root mean square error of prediction, RMSEP and residual predictive deviation, RPD. The efficiency of the developed model was significantly enhanced with the use of Si-PLS, Bi-PLS, and GA-PLS as compared to the classical PLS model. The R2 for calibration and r2 for prediction varied from 0.76 to 0.95 and 0.72 to 0.94, respectively. The obtained results revealed that NIR spectroscopy, coupled with different chemometric algorithms, has the potential to be used for rapid assessment of the antioxidant properties of peanut seed.

A new type of photocatalysts, nanocrystalline titanium dioxide (TiO2) doped with Co and I, were synthesized and modified via the sol-gel method to enhance the utilization of visible light. Herein, ...

Supramolecular coordination complexes with solid-state stimuli-responsive characteristics are highly desirable but are rarely reported. Herein, we describe two coordination-driven self-assembled monoanthracene or dianthracene-based hexagonal metallacycles by subtle structure modification. Notably, the dianthracene-containing hexagon 1 exhibits tricolor mechanochromic and vapochromic characteristics, while the monoanthracene-containing hexagon 4 does not show obvious changes toward mechanical force. Further studies have indicated that changes in hexagon 1, especially the ulterior anthracene of hexagon 1 in the molecular stacking through intermolecular interactions toward external stimuli, are responsible for the above behavioral differences. Furthermore, the present work also demonstrates a novel light-harvesting strategy for achieving high-contrast mechanochromic fluorescence involving solid-state energy transfer from hexagon 1 to an organic carbazole derivant 6 without mechanofluorochromism or tetraphenylethylene derivant 7 exhibiting inconspicuous mechanofluorochromism.

The development of organic nanoparticles that fluoresce in the near-infrared, especially in the second near-infrared (NIR-II) window, improves in vivo fluorescence imaging due to deeper penetration and higher spatiotemporal resolution. We report two kinds of NIR-II fluorescent molecules with twisted intramolecular charge-transfer (TICT) and aggregation-induced emission (AIE) characteristics. The virus-like particles (VLPs) of simian virus 40 (SV40) were used as templates to encapsulate the molecules in a well-defined structure (referred to as CH1-SV40 and CH2-SV40). The CH1-SV40 dots exhibited a highly uniform size of 21.5 nm, strong fluorescence, high photostability, and good biocompatibility in vitro and in vivo. Their fluorescence spectrum exhibited a peak at 955 nm, with a tail extending to 1200 nm. Moreover, the CH1-SV40 dots, with a quantum yield of 13.03%, enabled blood vessel imaging and image-guided surgery with a high signal-to-background ratio. Overall, the hybrid nanoparticles represent a new kind of NIR-II AIE nanoprobes for biomedical imaging.

Key message Non-additive genetic effects seem to play a substantial role in the expression of complex traits in sugarcane. Including non-additive effects in genomic prediction models significantly improves the prediction accuracy of clonal performance. Abstract In the recent decade, genetic progress has been slow in sugarcane. One reason might be that non-additive genetic effects contribute substantially to complex traits. Dense marker information provides the opportunity to exploit non-additive effects in genomic prediction. In this study, a series of genomic best linear unbiased prediction (GBLUP) models that account for additive and non-additive effects were assessed to improve the accuracy of clonal prediction. The reproducible kernel Hilbert space model, which captures non-additive genetic effects, was also tested. The models were compared using 3,006 genotyped elite clones measured for cane per hectare (TCH), commercial cane sugar (CCS), and Fibre content. Three forward prediction scenarios were considered to investigate the robustness of genomic prediction. By using a pseudo-diploid parameterization, we found significant non-additive effects that accounted for almost two-thirds of the total genetic variance for TCH. Average heterozygosity also had a major impact on TCH, indicating that directional dominance may be an important source of phenotypic variation for this trait. The extended-GBLUP model improved the prediction accuracies by at least 17% for TCH, but no improvement was observed for CCS and Fibre. Our results imply that non-additive genetic variance is important for complex traits in sugarcane, although further work is required to better understand the variance component partitioning in a highly polyploid context. Genomics-based breeding will likely benefit from exploiting non-additive genetic effects, especially in designing crossing schemes. These findings can help to improve clonal prediction, enabling a more accurate identification of variety candidates for the sugarcane industry.

The existing pulsed laser technologies and devices are mainly in the infrared spectral region below 3 μm so far. However, longer-wavelength pulsed lasers operating in the deep mid-infrared region (3-20 μm) are desirable for atmosphere spectroscopy, remote sensing, laser lidar, and free-space optical communications. Currently, the lack of reliable optical switches is the main limitation for developing pulsed lasers in the deep mid-infrared region. Here, we demonstrate that topological semimetal antimonene possesses an ultrabroadband optical switch characteristic covering from 2 μm to beyond 10 μm. Especially, the topological semimetal antimonene shows a very low saturable energy fluence (only 3-15 nJ cm-2 beyond 3 μm) and an ultrafast recovery time of ps level. We also demonstrate stable Q-switching in fiber lasers at 2 and 3.5 μm by using topological semimetal antimonene as passive optical switches. Combined with the high environmental stability and easy fabrication, topological semimetal antimonene offers a promising optical switch that extends pulsed lasers into deep mid-infrared region.

Pressure sensors were fabricated based on porous polymer films coated onto cotton fabric modified with reduced graphene oxide (rGO). The cotton fabric was modified with a silane coupling agent to improve the adhesion between the cotton fabric and rGO. The porous structure was constructed to enlarge the surface area of the coating polymer. The fabrication process was characterized with Fourier Transform Infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and Raman spectrometry. Owing to the materials and constructed porous structure, the prepared devices (1 × 2 cm2) showed an excellent electric output with a voltage of 132 V and an outstanding linear relationship of applied forces and frequencies with values of adjusted R2 over 0.97. In practical detection of human motion, the prepared pressure sensor gave clear signals for each step during the walking, jumping and running.

The production and characteristics of elemental sulfur were examined during simultaneous sulfide and nitrate removal, with abiotic assays as control. The biotic assay showed good sulfide and nitrate removal, with the respective removal percentage of which were 90.67–96.88% and 100%. Nitrate reduction resulted in the production of nitrogen gas, while sulfate formed due to sulfide oxidation. The concentration of elemental sulfur in the effluent was greater than that in the sludge, which accounted for 73.70–86.28% of total elemental sulfur produced. Furthermore, the elemental sulfur of the effluent and sludge from the biotic assays was orthorhombic crystal S8. Elemental sulfur was normally distributed in the effluent, but its average diameter increased with the increasing influent sulfide concentration (60–300 mg S/L), where the average diameter increased from 10 (60 mg S/L) to 29 μm (300 mg S/L).

A novel hemoglobin (Hb) imprinted polymers with CO2 response (CHIPs) were prepared on the surface of Au electrode modified by zinc oxide (CHIPs/ZnO/Au) via electrochemically mediated atom transfer radical polymerization (eATRP). The imprinted polymers were synthesized with Hb both as catalyst and template, and N,N-diethylaminoethyl methacrylate (DEAEMA) as CO2-responsive functional monomer. The obtained CHIPs/ZnO/Au electrode was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and electrochemical methods. The results showed that CHIPs/ZnO/Au electrode could give higher affinity for the target protein inside a CO2-treated aqueous medium compared to that under N2-treated conditions, which make it a good electrochemical biosensor in the presence of CO2. The biosensor could be successfully applied for the determination of Hb by differential pulse voltammetry (DPV) measurement. The linear response range of CHIPs/ZnO/Au for detecting Hb was 1.0×10−12~1.0×10−1 mg L−1 and the detection limit was 2.1×10−13 mg L−1 (S/N=3). Briefly, the work in this study introduced an easy and non-toxic method for Hb determination under specific conditions and also provided a progressive approach for designing protein imprinted polymers.

In this brief, a high-performance quasi-vertical GaN Schottky barrier diode (SBD) on sapphire substrate with post-mesa nitridation process is reported, featuring a low damaged sidewall with extremely low leakage current. The fabricated SBD with a drift layer of ${1}~\mu \text{m}$ has achieved a very high ON/ OFF current ratio ( ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}{)}$ of $10^{{12}}$ with a low leakage current of $\sim 10^{-{9}}$ A/cm2@-10 V, high forward current density of 5.2 kA/cm2 at 3 V in dc, a low differential specific ON-resistance ( ${R}_{ \mathrm{\scriptscriptstyle ON},\text {sp}}{)}$ of 0.3 $\text{m}\Omega \cdot $ cm2, and ideality factor of 1.04. In addition, a transmission-line-pulse (TLP) ${I}$ – ${V}$ test was carried out and 53 kA/cm2 at 30 V in pulsed measurement was obtained without device failure, exhibiting a great potential for high power applications.

Light‐dependent enzymes are a rare type of biocatalyst with high potential for research and biotechnology. A recently discovered fatty acid photo‐decarboxylase from Chlorella variabilis NC64A (CvFAP) converts fatty acids to the corresponding hydrocarbons only when irradiated with blue light (400 to 520 nm). To expand the available catalytic diversity for fatty acid decarboxylation, we reconstructed possible ancestral decarboxylases from a set of 12 extant sequences that were classified under the fatty acid decarboxylases clade within the glucose‐methanol choline (GMC) oxidoreductase family. One of the resurrected enzymes (ANC1) showed activity in the decarboxylation of fatty acids, showing that the clade indeed contains several photo‐decarboxylases. ANC1 has a 15 °C higher melting temperature (T m) than the extant CvFAP. Its production yielded 12‐fold more protein than this wild type decarboxylase, which offers practical advantages for the biochemical investigation of this photoenzyme. Homology modelling revealed amino acid substitutions to more hydrophilic residues at the surface and shorter flexible loops compared to the wild type. Using ancestral sequence reconstruction, we have expanded the existing pool of confirmed fatty acid photo‐decarboxylases, providing access to a more robust catalyst for further development via directed evolution., Enzyme resurrection strikes again: Ancestral sequence reconstruction was applied to a putative photo‐decarboxylases clade. One common ancestor showed up to 12‐fold production yield, a 15 °C increase in thermostability and up to 20‐fold improvement in residual activity when incubated at 50 °C. Ancestral sequence reconstruction proved to be a valuable tool to introduce valid mutations to a little understood fatty acid photo‐decarboxylase.

In the first half of winter 2020/21, China has experienced an extremely cold period across both northern and southern regions, with record-breaking low temperatures set in many stations of China. Meanwhile, a moderate La Nina event which exceeded both oceanic and atmospheric thresholds began in August 2020 and in a few months developed into its mature phase, just prior to the 2020/21 winter. In this report, the mid−high-latitude large-scale atmospheric circulation anomalies in the Northern Hemisphere, which were forced by the negative phase of Arctic Oscillation, a strengthened Siberian High, an intensified Ural High and a deepened East Asian Trough, are considered to be the direct reason for the frequent cold surges in winter 2020/21. At the same time, the synergistic effect of the warm Arctic and the cold tropical Pacific (La Nina) provided an indispensable background, at a hemispheric scale, to intensify the atmospheric circulation anomalies in middle-to-high latitudes. In the end, a most recent La Nina prediction is provided and the on-coming evolution of climate is discussed for the remaining part of the 2020/21 winter for the purpose of future decision-making and early warning.

To develop active and stable catalysts for CO oxidation at relatively higher temperature region for exhaust treatment, ZnAl2O4 spinel promoted by Fe and Co have been fabricated and characterized by different means. While Fe doping improves only slightly the activity, Co doping increases the activity remarkably. XRD and Raman results have proved that ZnAl2O4 spinel is the major phase for all the samples. By Fe doping, a new ZnFe2O4 spinel compound is formed. By Co doping, two new ZnCo2O4 and CoAl2O4 spinels are generated, which can provide both surface Co3+ and Co2+ sites for effective CO adsorption. XPS and EPR have testified that surface superoxide O2- anion is the major active oxygen sites for the reaction. It is disclosed that the concerted interaction between surface O2- species and CO adsorption sites determines the activity. Compared with the un-modified Zn-Al spinel sample, Fe doping improves slightly the amount of active oxygen species, but decreases the amount of CO adsorption sites. However, Co doping increases the amount of both kinds of sites evidently due to the formation of ZnCo2O4 and CoAl2O4 spinels. As a consequence, Zn-Co-Al exhibits the optimal activity in all the catalysts.

Ultrawide band gap semiconductor materials have attracted considerable attention in recent years owing to their great potential in the photocatalytic field. In this study, Zn-doped Ga2O3 nanofibers with various concentrations were synthesized via electrospinning; they exhibited a superior photocatalytic degradation performance of rhodamine B dye compared to that of undoped Ga2O3 nanofibers. The Zn dopant replaced Ga sites via replacement doping, which could increase the concentration of oxygen vacancies and lead to enhanced photocatalytic properties. When the Zn concentration increased, a Ga2O3/ZnGa2O4 hybrid structure formed, which could further enhance the photocatalytic performance. The separation of photogenerated carriers due to Zn doping and heterojunctions were the primary causes of the enhanced photocatalytic performance. This study provides experimental data for the fabrication of high-performance photocatalysts based on Ga2O3 nanomaterials.

In order to balance electrochemical kinetics with loading level for achieving efficient energy storage with high areal capacity and good rate capability simultaneously for wearable electronics, herein, 2D mesh-like vertical structures (NiCo2S4@Ni(OH)2) with a high mass loading of 2.17 mg cm−2 and combined merits of both 1D nanowires and 2D nanosheets are designed for fabricating flexible hybrid supercapacitors. Particularly, the seamlessly interconnected NiCo2S4 core not only provides high capacity of 287.5 μAh cm−2 but also functions as conductive skeleton for fast electron transport; Ni(OH)2 sheath occupying the voids in NiCo2S4 meshes contributes extra capacity of 248.4 μAh cm−2; the holey features guarantee rapid ion diffusion along and across NiCo2S4@Ni(OH)2 meshes. The resultant flexible electrode exhibits a high areal capacity of 535.9 μAh cm−2 (246.9 mAh g−1) at 3 mA cm−2 and outstanding rate performance with 84.7% retention at 30 mA cm−2, suggesting efficient utilization of both NiCo2S4 and Ni(OH)2 with specific capacities approaching to their theoretical values. The flexible solid-state hybrid device based on NiCo2S4@Ni(OH)2 cathode and Fe2O3 anode delivers a high energy density of 315 μWh cm−2 at the power density of 2.14 mW cm−2 with excellent electrochemical cycling stability.

In the process industries, the flammable and explosive hazards of aerosols receive less attention and have less understanding as compared to gases and dust clouds. Numerous incidents in various industries have revealed the distinct differences between the hazards of a bulk liquid compared to those of aerosols. Flash point, the criterion for liquid flammability becomes insignificant when the liquid is present in aerosol form. A practical discussion of the criteria for aerosol flammability hazard assessment is needed. Unlike standard measurements for gas and dust clouds, an aerosol flammability standard test method, such as ASTM D3065−01, has not been widely adopted owing to the lack of quantification. Therefore, it is important to establish quantitative aerosol flammability and aerosol explosion testing procedures. This paper comprehensively reviews the methodologies to generate aerosols, both lab and large-scale aerosol combustion and explosion experiments, and liquid flammability risk assessments. Additionally, this paper reviews important but sparsely studied areas such as aerosol deflagration to detonation transition (DDT) and proposes a systematic strategy to investigate the complicated mechanism and consequences of aerosol combustion and explosions.

Spatiotemporal fusion technique can combine the advantages of temporal resolution and spatial resolution of different images to achieve continuous monitoring for the Earth’s surface, which is a feasible solution to resolve the trade-off between the temporal and spatial resolutions of remote sensing images. In this paper, an object-based spatiotemporal fusion model (OBSTFM) is proposed to produce spatiotemporally consistent data, especially in areas experiencing non-shape changes (including phenology changes and land cover changes without shape changes). Considering different changes that might occur in different regions, multi-resolution segmentation is first employed to produce segmented objects, and then a linear injection model is introduced to produce preliminary prediction. In addition, a new optimized strategy to select similar pixels is developed to obtain a more accurate prediction. The performance of proposed OBSTFM is validated using two remotely sensed dataset experiencing phenology changes in the heterogeneous area and land cover type changes, experimental results show that the proposed method is advantageous in such areas with non-shape changes, and has satisfactory robustness and reliability in blending large-scale abrupt land cover changes. Consequently, OBSTFM has great potential for monitoring highly dynamic landscapes.

It is urgent to obtain targeted drugs that selectively bind to pathological targets rather than physiological targets in the early stage of drug screening. G-Quadruplex has become one of the important targets in the development of anti-tumor drugs. However, drugs that target quadruplexes may also bind to dsDNA, which may lead to adverse reactions. In this study, a new three-phase laminar flow chip was constructed to enable the multi-components of a traditional Chinese medicine extract to dynamically and competitively bind with G-quadruplex DNA (on target) and double-stranded DNA (off target), so as to select high-efficiency and low-toxicity anti-tumor drugs. The results showed that there were five compounds in the extracts of Macleaya cordata seeds that exhibited obvious differences in binding to the two targets. Furthermore, the binding constants and modes of four identified alkaloids as they bound to two DNA targets were verified by fluorescence spectra and molecular docking methods. The toxicity to HepG2 and LO2 cells from the four alkaloids was also compared. The results showed that sanguinarine and chelerythrine could be used as candidate drugs with stronger binding to HT24 than DNA26. The chip can also be used for other types of double-target screening of other traditional Chinese medicine extracts or compound libraries.

Polymer materials with mechanical energy-to-electricity conversion capability at high temperatures are highly desirable to develop energy harvesters, sensors, and other flexible devices for applications under harsh high-temperature conditions but remain an enormous challenge to develop. Herein, we report a polymer membrane that can convert mechanical energy into electricity at both room and high temperatures. The membranes were prepared by heat stabilization treatment of electrospun polyacrylonitrile (PAN) fibrous membranes to make PAN have a cyclized structure. The devices made of the treated PAN membranes can work at a temperature as high as 550 °C, which has never been reported on other polymer-based energy harvesting devices so far. A 2.5 × 2.5 cm2 device at 450 °C can generate a 9.7 V voltage (up to 62 V, 4 μA current) with a maximum power density of 26.4 mW cm−2. We further show that the oxidation cyclization of PAN due to stabilization treatment plays an essential role in achieving the high-temperature energy conversion. The energy conversion is mainly originated from a piezoelectric effect. We used the energy generated under high-temperature conditions to power commercial LEDs and charged capacitors to demonstrate the application. The electrical energy generated from a single device is sufficient to run a commercial LEDs. After rectification, it can also be stored in capacitors for further use. The PAN membranes are flexible and air permeable. They may form a novel polymer transducer candidate to develop flexible energy devices for various applications in high-temperature environments.

Although achieving significant improvement on pose estimation, the major drawback is that most top-performing methods tend to adopt complex architecture and spend large computational cost to achieve higher performance. Due to the edge device’s limited resources, its top-performing methods are hard to maintain fast inference speed in practice. To address this issue, we proposed the fast and lightweight human pose estimation method to maintain high performance and bear the less computational cost. Especially, the proposed method consists of two parts, i.e., the fast and lightweight pose network (FLPN) for pose estimation and a novel lightweight bottleneck block for reducing computational cost, which can integrate the simple network and lightweight bottleneck into an efficient method for accurate pose estimation. In terms of lightweight bottleneck block, we introduce the structural similarity measurement (SSIM) to refine the appropriate ratio of intrinsic feature maps and reduce the model size. Furthermore, an attention mechanism is also adopted in our lightweight bottleneck block for modeling the contextual information. We demonstrate the performance of the proposed method with extensive experiments on the two standard benchmark datasets by comparing our method with state-of-the-art methods. On the COCO keypoint detection dataset, our proposed method attains a similar accuracy with these state-of-the-art methods, but the computational cost of these top-performing methods is more than 7 times that of ours.

A regional Arctic Ocean configuration of the Massachusetts Institute of Technology General Circulation Model (MITgcm) is applied to simulate the Arctic sea ice from 1991 to 2012. The simulations are evaluated by comparing them with observations from different sources. The results show that MITgcm can reproduce the interannual and seasonal variability of the sea-ice extent, but underestimates the trend in sea-ice extent, especially in September. The ice concentration and thickness distributions are comparable to those from the observations, with most deviations within the observational uncertainties and less than 0.5 m, respectively. The simulated sea-ice extents are better correlated with observations in September, with a correlation coefficient of 0.95, than in March, with a correlation coefficient of 0.83. However, the distributions of sea-ice concentration are better simulated in March, with higher pattern correlation coefficients (0.98) than in September. When the model underestimates the atmospheric influence on the sea-ice evolution in March, deviations in the sea-ice concentration arise at the ice edges and are higher than those in September. In contrast, when the model underestimates the oceanic boundaries’ influence on the September sea-ice evolution, disagreements in the distribution of the sea-ice concentration and its trend are found over most marginal seas in the Arctic Ocean. The uncertainties of the model, whereby it fails to incorporate the atmospheric information in March and oceanic information in September, contribute to varying model errors with the seasons.

Supramolecular coordination complexes (SCCs) have emerged as anticancer agents. Tracking the movement of these metallic anticancer agents plays an important role in the field of biomedicines. Herein, we describe a method for tracking the movement of a rhomboidal Pt(II) metallacycle agent using the quantum dots encapsidation in vitro self-assembly system of viral proteins. When incubated with living Vero cells, self-assembly of hybrid viral nanoparticles were employed for simultaneous cell imaging and visual transmission of the Pt(II) metallacycle agent. Considering these results, we believe that the multifunctional biomaterials consisting of a supramolecular coordination complex and quantum dots provide a new alternative for probing of the delivery of Pt(II) metallacycle drugs.

Fetal nucleated red blood cells (fNRBCs) in maternal peripheral blood containing the whole genetic information of the fetus may serve for noninvasive pregnant diagnostics (NIPD). However, the fetal cell-based NIPD is seriously limited by the poor purity of the isolated fNRBCs. Recently, the biomimetic cell membrane-camouflaged nanoparticles containing outstanding features have been widely used to detect and isolate rare cells from the peripheral blood samples. In this work, enythrocyte (RBC) and leukocyte (WBC) membranes are fused and coated onto magnet nanoparticles and then modified with anti-CD147 to isolate fNRBCs from the maternal peripheral blood with significant efficiency (∼90%) and purity (∼87%) in simulated spiked blood samples. Further, fNRBCs were isolated and identified from a series of maternal peripheral blood samples coming from pregnant women of 11-13 gestational weeks, and different chromosomal aneuploidies were diagnosed using fNRBCs isolated from maternal blood in early pregnancy. Our strategy may offer additional opportunity to overcome the limitations of current cell-based NIPD platforms.

In order to enhance the charge storage capability of carbonaceous fibers for wearable supercapacitors, efforts have been devoted to the incorporation of transition metal dichalcogenides (e.g., MoS2), nevertheless the improvement is moderate since the electrochemical properties of MoS2 severely depend on their crystal phase and interlayer spacing. Herein, a facile space-confined hydrothermal method is developed to synthesize graphene fibers embedded with expanded 1T-enriched MoS2 in a single-step. In such a fiber configuration, 1T phase enables MoS2 hydrophilicity and high electrical conductivity while expanded interlayer spacing facilitates fast ion intercalation/de-intercalation. The hybrid fibers exhibit significantly enhanced volumetric specific capacitance (CV) of 491.1 F cm-3 for single electrode and 44.6 F cm-3 for solid-state device, respectively, with good rate performance and excellent cycling stability.

The two-dimensional surfaces have been fueled by the infinite possibility they offered for basic research, and for novel technologies in nanoelectronics. To realize many of these promises, the effective strategies were to design and control their surface chemistry, which plays a vital role in determining the chemical and physical properties. Macrocyclic host–guest chemistry with the reversible noncovalent interactions between macrocyclic hosts and suitable guests can be readily used for constructing multifunctional surfaces. Macrocyclic pillararenes, possessed the unique structure, have attracted the attentions of researchers in recent years. This feature article covers the recent development of pillararene-based two-dimensional interfaces, including the fabrication and function of the hybrid composite. The combination of pillararenes and materials platform exhibited the novel property because of the characteristic of cavity of macrocyclic host and confined spaces of surfaces. We anticipate that this review will be helpful to the researchers working in the fields of supramolecular chemistry and materials science.

One-dimensional compression tests on quartz sands treated by microbially induced carbonate precipitation (MICP) were carried out to evaluate the effects of gradation and calcium carbonate (CaCO3) content on compression behaviors. The experimental results reveal that the compressibility of specimens increases with increasing coefficient of uniformity or decreasing CaCO3 content. The evolution of void ratio with vertical stress could be generally characterized into three stages based on the underlying mechanisms. The initiation of bond breakage occurs around vertical stress of 0.036 MPa, and the dominating mechanism transits to particle breakage around vertical stress of 8.3 MPa. Scanning electron microscope analyses demonstrate that bonding effect and coating effect of CaCO3 precipitation are responsible for the lower compressibility of MICP-treated specimen. The presence of small particles leads to more interparticle CaCO3 bonds whose breakage would still allow the small particles to fill the intercoarse-grain voids.

Enzyme mimics have been developed as a new generation of antibiotics with broad-spectrum antibacterial properties to combat bacteria. In this study, a peroxidase mimic was constructed from nanodiamonds (NDs) to treat periodontal pathogen-induced infections with decreasing damage of periodontal tissues by traditional drug therapy. The oxygenated nanodiamonds (O-NDs) have excellent enzymatic activity over a broad pH range, and locally activated free-radical generations from low concentration of hydrogen peroxide, presenting a significantly enhancement in bacterial cell membrane disruptions and breaking down biofilms. In the presence of trace non-toxic hydrogen peroxide, topical rinse treatments with O-NDs restrain the development of bacterial infection in vivo, thus preventing and ameliorating the course of periodontal inflammation in a rodent model. More importantly, the enzymatic activity of O-NDs can accelerate the wound healing around sites of periodontal infection in time. The platform of nanodiamond-based enzyme mimic is built having high performance antibiotic-free periodontal antibacterial therapy, and can be extended to other fields of medical applications.

A non-pillar coal-mining technology with an automatically formed entry is proposed, which reduces the waste of coal resources and the underground entry drivage workload. Three key techniques in this technology cooperate to achieve automatic formation and retaining of the gob-side entry, and to realize non-pillar mining. Constant-resistance large deformation (CRLD) support ensures the stability of the entry roof; directional presplitting blasting (DPB) separates the entry roof and the gob roof; and a blocking-gangue support system (BGSS) integrates the caved rock material as an effective entry rib. An industrial test was conducted to verify the engineering effects of these key techniques. The field application results showed that the retained entry was under the pressure-relief zone due to the broken-expansion nature of the caved rock mass within the DPB height. After going through a provisional dynamic pressure-bearing zone, the retained entry entered the stability zone. The final stable entry meets the requirements of safety and production. The research results demonstrate the good engineering applicability of this technology. By taking the framework of the technology design principles into consideration and adjusting the measures according to different site conditions, it is expected that the proposed non-pillar coal-mining technology can be popularized on a large scale.

In order to obtain more effective antitumor agents, a new class of 1,2,4-triazole derivatives bearing disulfide bond were designed and synthesized. All the final compounds were confirmed by IR, 1H NMR, 13C NMR and HR-ESI-MS. The in vitro cytotoxicity of the compounds on the SMMC-7721, Hela, A549 cancer cell lines and the L929 normal cell lines were assessed by cell counting kit-8 (CCK-8). Many of tested compounds 8a–h, 9a–h, 10a–h had better cytotoxic activity on various cancer cell lines than positive control 5-fluorouracil, and they were less cytotoxic to normal cell line L929 than cancer cells. Among them, compounds 9e, 9g, and 10h showed better cytotoxic activity on SMMC-7721 cells with IC50 values 4.12, 2.92, and 4.53 μM, respectively. Compounds 8a, 9g, 10g and 10h displayed high antiproliferative activity against Hela cells with IC50 values 6.31, 4.31, 6.31 and 3.97 μM, respectively. Compounds 8c, 10a and 10h revealed effective biological potency on A549 cells with IC50 values 4.75, 4.92 and 3.73 μM, respectively. Moreover, a great majority of tested compounds revealed low cytotoxicity on normal cell line L929.

The low specific capacity and sluggish electrochemical reaction kinetics greatly block the development of sodium-ion batteries (SIBs). New high-performance electrode materials will enhance development and are urgently required for SIBs. Herein, we report the preparation of supersaturated bridge-sulfur and vanadium co-doped MoS2 nanosheet arrays on carbon cloth (denoted as V-MoS2+x/CC). The bridge-sulfur in MoS2 has been created as a new active site for greater Na+ storage. The vanadium doping increases the density of carriers and facilitates accelerated electron transfer. The synergistic dual-doping effects endow the V-MoS2+x/CC anodes with high sodium storage performance. The optimized V-MoS2.49/CC gives superhigh capacities of 370 and 214 mAh·g−1 at 0.1 and 10 A·g−1 within 0.4−3.0 V, respectively. After cycling 3,000 times at 2 A·g−1, almost 83% of the reversible capacity is maintained. The findings indicate that the electrochemical performances of metal sulfides can be further improved by edge-engineering and lattice-doping co-modification concept.

This paper studies in-situ synthesis of Fe2O3/reduced graphene oxide (rGO) anode materials by different hydrothermal process.Scanning Electron Microscopy (SEM) analysis has found that different processes can control the morphology of graphene and Fe2O3. The morphologies of Fe2O3 prepared by the hydrothermal in-situ and oleic acid-assisted hydrothermal in-situ methods are mainly composed of fine spheres, while PVP assists The thermal in-situ law presents porous ellipsoids. Graphene exhibits typical folds and small lumps. X-ray diffraction analysis (XRD) analysis results show that Fe2O3/reduced graphene oxide (rGO) is generated in different ways. Also, the material has good crystallinity, and the crystal form of the iron oxide has not been changed after adding GO. It has been reduced, and a characteristic peak appears around 25°, indicating that a large amount of reduced graphene exists. The results of the electrochemical performance tests have found that the active materials prepared in different processes have different effects on the cycle performance of lithium ion batteries. By comprehensive comparison for these three processes, the electro-chemical performance of the Fe2O3/rGO prepared by the oleic acid-assisted hydrothermal method is best.

The blue king crab, Paralithodes platypus, which belongs to the family Lithodidae, is a commercially and ecologically important species. However, a high‐quality reference genome for the king crab has not yet been reported. Here, we assembled the first chromosome‐level blue king crab genome, which contains 104 chromosomes and an N50 length of 51.15 Mb. Furthermore, we determined that the large genome size can be attributed to the insertion of long interspersed nuclear elements and long tandem repeats. Genome assembly assessment showed that 96.54% of the assembled transcripts could be aligned to the assembled genome. Phylogenetic analysis showed the blue king crab to have a close relationship with the Eubrachyura crabs, from which it diverged 272.5 million years ago. Population history analyses indicated that the effective population of the blue king crab declined sharply and then gradually increased from the Cretaceous and Neogene periods, respectively. Furthermore, gene families related to developmental pathways, steroid and thyroid hormone synthesis, and inflammatory regulation were expanded in the genome, suggesting that these genes contributed substantially to the environmental adaptation and unique body plan evolution of the blue king crab. The high‐quality reference genome reported here provides a solid molecular basis for further study of the blue king crab's development and environmental adaptation.

A flexible, biocompatible, nitrile butadiene rubber (NBR)-based strain sensor with high stretchability, good sensitivity, and excellent repeatability is presented for the first time. Carbon black (CB) particles were embedded into an NBR matrix via a dissolving-coating technique, and the obtained NBR/CB composite was coated with polydopamine (PDA) to preserve the CB layer. The mechanical properties of the NBR films were found to be significantly improved with the addition of CB and PDA, and the produced composite films were noncytotoxic and highly biocompatible. Strain-sensing tests showed that the uncoated CB/NBR films possess a high sensing range (strain of ∼550%) and good sensitivity (gauge factor of 52.2), whereas the PDA/NBR/CB films show a somewhat reduced sensing range (strain of ∼180%) but significantly improved sensitivity (gauge factor of 346). The hysteresis curves obtained from cyclic strain-sensing tests demonstrate the prominent robustness of the sensor material. Three novel equations were developed to accurately describe the uniaxial and cyclic strain-sensing behavior observed for the investigated strain sensors. Gloves and knee/elbow covers were produced from the films, revealing that the signals generated by different finger, elbow, and knee movements are easily distinguishable, thus confirming that the PDA/NBR/CB composite films can be used in a wide range of wearable strain sensor applications.

Lilies (Lilium spp.) are famous bulb flowers worldwide with high ornamental value. Somatic embryogenesis in plants, which exhibits the advantages of universal occurrence, genetic stability, and suitability as an exogenous gene transfer receptor system, is vital to bulb propagation, germplasm preservation, genetic trait improvement and polyploid breeding in Lilium. This review systematically summarizes the current research progress on Lilium somatic embryogenesis and provides information on the influencing factors, procedures, and physiological and molecular mechanisms of somatic embryogenesis; the applications and prospects of somatic embryogenesis in the lily industry; and the difficulties associated with Lilium somatic embryogenesis. This review aims to provide comprehensive and valuable information for future research on somatic embryogenesis in Lilium. This review provides the first report on the research progress in Lilium somatic embryogenesis. The review analyzes main factors affecting this developmental pathway, its physiological and molecular mechanisms, and its application in the lily industry and discusses the research difficulties and application prospects of somatic embryogenesis in Lilium.

Cost-effective H2 detection sensors based on pure and CeO2 (0.5 at%, 1 at%, 1.5 at%, 2 at%, 3 at%, 4 at%)-doped SnO2 semiconductor oxides with both high moisture resistance and low operation temperature were prepared by a simple method. The crystal phase, morphology, and chemical composition of the obtained CeO2-doped SnO2 sample were analyzed and related with the sensing properties. The results show that the H2 sensing performance of pure SnO2 gas sensor can be improved a lot by CeO2 doping. In particular, gas sensors based on 2 at% CeO2/SnO2 exhibited the greatest performance: high responsiveness at 160 °C (23.7 for 50 ppm hydrogen), about 3 times higher than pure SnO2 sensor (6.9); short response and recovery time (2 and 9 s); good repeatability and long-term stability without any change after 30 days (23.7 for 50 ppm hydrogen), good selectivity, and moisture resistance. Finally, the function of CeO2 on SnO2 gas sensor for H2 detection is discussed.

In this study, a novel asymmetric amine-based strongly basic anion exchange resin SE-1 was synthesized successfully via the reaction of chloromethylated styrene–divinylbenzene copolymer with N, N-dimethyloctylamine. The sorption performance of SE-1 for selective removal of nitrate in aqueous solution was compared to a commercially available nitrate specialty resin, namely Purolite A 520E (A 520E). It was found that the kinetic data could be described better by the pseudo-second-order model, and SE-1 indicated a faster sorption kinetics than A 520E resin. The Langmiur model was more appropriate for explicating the sorption isotherm. Importantly, SE-1 exhibited a greater sorption capacity for nitrate regardless of the absence or presence of competing anions in solutions. The result of column tests reinforced the feasibility of SE-1 for practical application in groundwater treatment.

Spontaneous symmetry breaking has been a paradigm to describe the phase transitions in condensed matter physics. In addition to the continuous electromagnetic gauge symmetry, an unconventional superconductor can break discrete symmetries simultaneously, such as time reversal and lattice rotational symmetry. In this work we report a characteristic in-plane 2-fold behaviour of the resistive upper critical field and point-contact spectra on the superconducting semimetal PbTaSe2 with topological nodal-rings, despite its hexagonal lattice symmetry (or D_3h in bulk while C_3v on surface, to be precise). However, we do not observe any lattice rotational symmetry breaking signal from field-angle-dependent specific heat. It is worth noting that such surface-only electronic nematicity is in sharp contrast to the observation in the topological superconductor candidate, CuxBi2Se3, where the nematicity occurs in various bulk measurements. In combination with theory, superconducting nematicity is likely to emerge from the topological surface states of PbTaSe2, rather than the proximity effect. The issue of time reversal symmetry breaking is also addressed. Thus, our results on PbTaSe2 shed new light on possible routes to realize nematic superconductivity with nontrivial topology., Comment: 3 figures

In winter, the warm water of the Gulf Stream anchors a salient precipitation band. Previous studies suggested a close relationship between the sea surface temperature (SST) front and the precipitation band through sea level pressure (SLP) adjustment. This study uses 17 years of high-resolution precipitation observations to reveal that the variation in wintertime precipitation over the Gulf Stream is related to the North Atlantic Oscillation (NAO) at the interannual time scale. The moisture budget analysis shows that the climatological precipitation band is supported by the large evaporation from the Florida Current, mean flow, and synoptic moisture convergence within the boundary layer, with a negative contribution from mean-flow moisture advection by the prevailing northwesterlies. For interannual variability, by contrast, the negative contribution of mean-flow moisture advection significantly decreases due to anomalous southeasterlies west of the intensified Azores high at the positive NAO phase. The contributions from mean-flow moisture advection and mean and synoptic convergence vary greatly along the Gulf Stream. In addition, mean-flow and synoptic moisture convergences positively contribute to the precipitation band both in climatology and at the interannual time scale, indicative of a positive feedback between precipitation and boundary layer convergence. Our analysis suggests that the SLP adjustment mechanism across the SST front is still at work in interannual variability, and the variation of synoptic activities over the Gulf Stream plays an important role in modulating the frontal precipitation. By relating the frontal precipitation to the NAO, this study bridges small-scale air–sea interaction and large-scale atmospheric circulation.

In this study, we developed a sensitive and selective sensing system for the detection of metallothioneins (MTs). The system is based on the fluorescence resonance energy transfer (FRET) between carbon quantum dots (CQDs) and gold nanoparticles (AuNPs). In this method, the fluorescence emission of CQDs was quenched by AuNPs due to FRET. When MTs were added to the CQD–AuNP system, the strong combination between thiol group and Au made the CQDs release from AuNPs, and the fluorescence of CQDs was recovered. The CQD–AuNP system can detect the MTs in aqueous solution (pH 3.0, citrate–HCl buffer) selectively and sensitively with a short response time (15 min). Results show that the fluorescence recovery efficiency has a good linear relationship with the MTs concentration in the range of 12–210 nmol L−1, and the limit of detection was 5.25 × 10−9 mol L−1. Furthermore, the sensing system was utilized to determine MTs in human urine samples with satisfactory results. The proposed system exhibits the advantages of high sensitivity, high selectivity, easy operation and most importantly, low cost and non-cytotoxicity to detect protein MTs.

The overuse of antibiotics has led to the emergence of multidrug-resistant pathogens. There is an urgent need to develop alternative therapeutic strategies to reduce mortality and morbidity related to drug-resistant bacterial infections. Self-synthesized tetrahedral framework nucleic acids (tFNAs) are used as the drug loading platform to deliver ampicillin to combat methicillin-resistant Staphylococcus aureus (MRSA) infection. The results of average dimension, zeta potential, transmission electron microscopy, and ultraviolet spectrophotometry showed that tFNAs-ampicillin combined with a sufficient encapsulation rate and good stability. tFNAs-ampicillin had a better affinity to MRSA than free ampicillin because it had a better uptake by MRSA cells. Additionally, tFNAs-ampicillin had a better antibacterial effect and lower levels of resistance development than free ampicillin. The downregulation of genes related to bacterial cell wall synthesis (murA and murZ) and upregulation of a gene related to antibiotic sensibility (PBP2) were responsible for the enhanced killing effect of tFNAs-ampicillin against MRSA.

Based on particle image velocimetry (PIV) technology, the process and flow field characteristics of slag entrapment under the condition of critical slag entrapment are investigated by water model. ...