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Dielectric metasurfaces hold an exceptional potential for the next generation of tunable optical systems that find applications in sensing, ranging, and imaging. Here, we introduce and demonstrate magnetic field tuning of dielectric metasurfaces infiltrated with liquid crystals. To illustrate this concept, we show how the reorientation of liquid crystal induced by the magnetic field changes the spectrum of the resonant dielectric metasurface. This new magnetic-field tuning approach offers significant advantages over other liquid crystal tuning methods since it does not require pre-alignment or the fabrication of structured electrodes, which are both challenging when dealing with metasurfaces. Furthermore, there are no strict limitations on the thickness of liquid crystal cells. Importantly, our approach allows for gradual tuning of the resonances by changing the magnetic-field orientation and, thereby, shows good promise for highly tunable optical metadevices.

Spermatogenesis is a cyclical process in which different generations of spermatids undergo a series of developmental steps at a fixed time and finally produce spermatids. Here, we report that overexpression of PD-L1 (B7 homolog1) in the testis causes sperm developmental disorders and infertility in male mice, with severe malformation and sloughing during spermatid development, characterized by disorganized and collapsed seminiferous epithelium structure. PD-L1 needs to be simultaneously expressed on Sertoli cells and spermatogonia to cause spermatogenesis failure. After that, we excluded the influence of factors such as the PD-L1 receptor and humoral regulation, confirming that PD-L1 has an intrinsic function to interact with PD-L1. Studies have shown that PD-L1 not only serves as a ligand but also plays a receptor-like role in signal transduction. PD-L1 interacts with PD-L1 to affect the adhesive function of germ cells, causing malformation and spermatid sloughing. Taken together, these results indicate that PD-L1 can interact with PD-L1 to cause germ cell detachment and male infertility.

The ability to construct metal single-atom catalysts (SACs) asymmetrically coordinated with organic heteroatoms represents an important endeavor toward developing high-performance catalysts over symmetrically coordinated counterparts. Moreover, it is of key importance in creating supporting matrix with porous architecture for situating SACs as it greatly impacts the mass diffusion and transport of electrolyte. Herein, we report the crafting of Fe single atoms with asymmetrically coordinated nitrogen (N) and phosphorus (P) atoms scaffolded by rationally designed mesoporous carbon nanospheres (MCNs) with spoke-like nanochannels for boosting ring-opening reaction of epoxide to produce an array of pharmacologically important β -amino alcohols. Notably, interfacial defects in MCN derived from the use of sacrificial template create abundant unpaired electrons, thereby stably anchoring N and P atoms and in turn Fe atoms on MCN. Importantly, the introduction of P atom promotes the symmetry-breaking of common four N-coordinated Fe sites, resulting in the Fe-N 3 P sites on MCN (denoted Fe-N 3 P-MCN) with an asymmetric electronic configuration and thus superior catalytic capability. As such, the Fe-N 3 P-MCN catalysts manifest a high catalytic activity for ring-opening reaction of epoxide (97% yield) over the Fe-N 3 P docked on nonporous carbon surface (91%) as well as the sole Fe-N 4 SACs grounded on the same MCN support (89%). Density functional theory calculations reveal that Fe-N 3 P SAC lowers the activation barrier for the C–O bond cleavage and the C–N bond formation, thus accelerating the ring-opening of epoxide. Our study provides fundamental and practical insights into developing advanced catalysts in a simple and controllable manner for multistep organic reactions.

Sequential separation-driven steam methane reforming derives low-carbon-footprint H2 with >99% conversion (CH4), yield and selectivity (H2 & CO2) and low energy penalty at 400 °C and 1 bar, and integrates well with solar trough technology.

Background The clinicopathological value and exploration of the potential molecular mechanism of microRNA-183-5p (miR-183-5p) have been investigated in various cancers. This study further explored the transcriptome profile regulated by miR-183-5p. Methods Messenger RNA (mRNA) expression data, miRNA expression, and clinical information of stomach adenocarcinoma (STAD) were downloaded from The Cancer Genome Atlas (TCGA) database. Differentially expressed genes (DEGs) that related to mir-189-5p expression and cancer proliferation were acquired using bioinformatics analysis. The biological functions of these genes were analyzed in terms of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Hub genes relating to gastric cancer (GC) signal pathway were explored. The results were validated by further experiments. Results A total of 308 genes were found to be regulated by miR-183-5p, and they were related to cancer and GC patients' survival outcome. The biological function of these genes was found to act mainly on biological processes and the involved signal pathways included neuroactive ligand-receptor interaction, cell adhesion molecules, and axon guidance. In addition, miR-183-5p was also shown to regulate the mTOR, Wnt, MAPK, and PI3K-Akt signaling pathways through the genes WNT2B, NGFR, and NTRK2. Conclusions The miRNA miR-183-5p participates in the tumorigenesis and development of GC via certain signaling pathways, in particular the nerve- and immunity-related genes.

Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies. Vasorin (VASN) has been reported to be critical in tumor development and angiogenesis. However, VASN has not been reported in CRC, and its role is unclear. In this study, VASN expression is upregulated in CRC compared with the normal tissues, and VASN expression positively correlates with N stage and poor overall survival by analysis of different datasets and 32 CRC clinicopathologic samples. Overexpression of VASN significantly promotes CRC cell progression, including proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT), while knockdown of VASN inhibits CRC progression. We found that VASN was associated with the YAP/TAZ and PI3K/AKT pathways by gene set enrichment analysis (GSEA) and gene ontology (GO) analysis. Notably, western blotting, immunofluorescence staining and co-immunofluorescence (co-IP) confirmed that VASN could interact with YAP and activate the YAP/TAZ and PTEN/PI3K/AKT pathways, and knockdown of YAP reversed this effect. Importantly, our findings indicate that VASN interacts with YAP to inhibit YAP phosphorylation and stimulates CRC proliferation, migration, and invasion through activation of the YAP/TAZ-TEAD target gene CTGF and PTEN/PI3K/AKT pathways. Our results also show that knockdown of YAP reverses the cellular phenotype induced by increased VASN. In conclusion, our study reveals that VASN acts as an oncogene to stimulate tumor progression in CRC, providing new insights into the molecular mechanisms of CRC development and representing a possible novel biomarker for CRC.

Colorectal cancer (CRC) is the third frequent cancer and second leading reason of cancer-related mortality all over the globe. Saponins from Platycodi radix (SPR) and microRNAs (miRNAs) have been reported to regulate CRC cell progression. Real-time quantitative polymerase chain reaction (RT-qPCR) detected miR-181c-5p, miR-181d-5p, and RBM47 expression level. Cell counting kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU), colony formation, transwell, and wound healing assays validated that miR-181c-5p and miR-181d-5p promote CRC cell proliferation, migration and invasion and SPR exerts opposite effects. Cignal Finder Reporter Array and western blot proved that the activity of PI3K/AKT pathway was decreased by RBM47 overexpression. RNA pulldown, luciferase reporter, and RNA-binding protein immunoprecipitation (RIP) assays proved the interaction between miR-181c/d-5p and RBM47, and RBM47 and PTEN. Rescue experiments were carried out to validate that RBM47 reverses the influence of miR-181c/d-5p on the progression of CRC cells. The stability of PTEN was probed by real-time quantitative polymerase chain reaction in CRC cells treated with Actinomycin D (Act D). To be concluded, SPR inactivates PI3K/AKT signaling pathway to suppress CRC cell proliferation, invasion, and migration via miR-181c/d-5p/RBM47. Elucidating the mechanisms of SPR underlying CRC may offer novel insight into CRC treatment.

Building a precise, sensitive, and selective sensing platform is highly significant for microRNA (miRNA) detection. Herein, an innovative ratiometric electrochemical biosensor sensitized with carbon nanoparticles-functionalized SnS2 nanoflowers (C@SnS2 NFs) and enzyme-assisted target recycling was explored for analysis of miRNA-21. In this strategy, the application of hierarchical C@SnS2 NFs structure as electrode material not only enhanced the surface loading capability for subsequent reactions but also improved the interfacial electron transfer. After introducing enzyme-assisted target recycling, single-target miRNA-21 could initiate the cleavage of multiple capture DNA strands by duplex-specific nuclease (DSN), leading to numerous rest single-strand DNAs on the electrode. Two probes, methylene blue-labeled probe 1 (probe 1-MB) and ferrocene-labeled probe 2 (probe 2-Fc), could selectively and competitively hybridize with the capture DNA and the rest single-strand DNA, depending on the completeness of DNA hybridization. By measuring the peak current intensity ratio of Fc and MB, miRNA-21 was quantified in a wide concentration range from 1 fmol/L to 10 pmol/L, with a detection limit of 300 amol/L. Moreover, this sensing system showed good analytical performance in the presence of interfering sequences and complex matrices, illuminating excellent selectivity and practical application potential of the hierarchical C@SnS2 NF sensing interface.

Platinum nanocrystals featuring a multiply twinned structure and uniform sizes below 5 nm are superb catalytic materials, but it is difficult to synthesize such particles owing to the high twin-boundary energy (166 mJ/m2) of Pt. Here, we report a simple route to the synthesis of such nanocrystals by selectively growing them from the vertices of Pd icosahedral seeds. The success of this synthesis critically depends on the introduction of Br- ions to slow the reduction kinetics of the Pt(II) precursor while limiting the surface diffusion of Pt adatoms by conducting the synthesis at 30 °C. Owing to the small size and multiply twinned structure of Pt dots, the as-obtained Pd-Pt nanocrystals show remarkably enhanced activity and durability toward oxygen reduction, with a mass activity of 1.23 A mg-1Pt and a specific activity of 0.99 mA cm-2Pt, which are 8.2 and 4.5 times as high as those of the commercial Pt/C.

Lithium–sulfur (Li–S) battery is one of the most promising next-generation energy storage systems. Nevertheless, owing to the high solubility of lithium polysulfides (LiPSs) in the ether-based electrolyte, plenty of LiPSs shuttle between cathode and anode under an electric field. This shuttle effect corrodes the lithium metal, and thus causes serious capacity fading, which is regarded as a major barrier to the commercial application of Li–S batteries. Engineering the surficial structure of nanomaterials can promote affinity between cathode and LiPSs, while simultaneously facilitating redox kinetics of LiPSs, leading to a low concentration of LiPSs in electrolyte for restraining the shuttle effect. Herein, we review recent progress in manipulating the electronic structure of nanomaterials featuring high conductivity, strong absorption and catalytic properties for Li–S batteries. We first discuss the mechanism of the conversion of LiPSs with different pathways. Moreover, we showcase the design strategies of nanomaterials with the modulated surface, including heterostructures, deficiency strategy, heteroatom-doping strategy and metal-single-atom catalyst. Future perspectives and challenges are also proposed for constructing stable Li–S batteries with high energy density.

Single-atom and double-atom catalysts have emerged as a new Frontier in many fields due to their high atom-utilization efficiency, excellent catalytic properties and good durability. In this decade, Fe-based atomic catalysts have exhibited great advantages toward the oxygen reduction reaction (ORR) owing to the high utilization efficiency of their single/dual atomic sites, well-defined active sites and high selectivity toward the four-electron (4e−) pathway. To explore their catalytic behavior, many efforts have been made to synthesize Fe-based atomic catalysts. In addition, the high performance of Fe-based single/dual atoms toward ORR is mainly attributed to the critical coordination condition and the corresponding electronic structures. Currently, it is a great challenge to achieve high activity and good stability with a high content of metal atoms, while maintaining their atomic dispersion. In this review, we begin with a systematic review about the influence of the coordination environment of Fe-based single/dual-atom catalysts on their electrocatalytic properties, followed by an overview of some new strategies to improve their coordination environment. Then, we present a comprehensive summary on the advantages of their unique structures, catalytic activity for the ORR and further applications. Finally, the remaining key challenges and future opportunities in this emerging field are concluded to provide more useful clues for the development of advanced catalysts.

The ability to restrict the shuttle of lithium polysulfide (LiPSn) and improve the utilization efficiency of sulfur represents an important endeavor toward practical application of lithium–sulfur (...

China is promoting the production and use of electric vehicles (EVs) to achieve carbon neutrality. However, the shift will drive higher demand and tighter supply of nickel in China. We develop a stock-driven bottom-up dynamic substance flow analysis (SFA) model to simulate the demand trends of various EVs under 3 scenarios, the flow of nickel under 9 scenarios and the amount of recoverable nickel under 27 scenarios in China's EV industry from 2010 to 2050. The results indicate that China's current production capacity and primary reserves of nickel cannot meet the growing nickel demand, especially under the High EVs-LNCT scenarios, and closed-loop nickel recovery from EV batteries can effectively alleviate the demand-supply contradiction. In different scenarios, the annual recycling nickel could cover between 67.7 % and 96.6 % of the demand for EV batteries in 2050, and between 37.9 % and 58.1 % in terms of the cumulative quantity by 2050. When the low nickel battery technology is adopted and the recovery efficiency is rapidly improved, the recovered nickel would meet the demand for EV batteries to the highest degree. Therefore, sufficient attention should be paid to low-nickel battery technology and efficient recycling of spent EV batteries, which is of great significance to ensure the development of EV industry and the availability of nickel in China.

Solar fuel generation from thermochemical H2O or CO2 splitting is a promising and attractive approach for harvesting fuel without CO2 emissions. Yet, low conversion and high reaction temperature restrict its application. One method of increasing conversion at a lower temperature is to implement oxygen permeable membranes (OPM) into a membrane reactor configuration. This allows for the selective separation of generated oxygen and causes a forward shift in the equilibrium of H2O or CO2 splitting reactions. In this research, solar-driven fuel production via H2O or CO2 splitting with an OPM reactor is modeled in isothermal operation, with an emphasis on the calculation of the theoretical thermodynamic efficiency of the system. In addition to the energy required for the high temperature of the reaction, the energy required for maintaining low oxygen permeate pressure for oxygen removal has a large influence on the overall thermodynamic efficiency. The theoretical first-law thermodynamic efficiency is calculated using separation exergy, an electrochemical O2 pump, and a vacuum pump, which shows a maximum efficiency of 63.8%, 61.7%, and 8.00% for H2O splitting, respectively, and 63.6%, 61.5%, and 16.7% for CO2 splitting, respectively, in a temperature range of 800 °C to 2000 °C. The theoretical second-law thermodynamic efficiency is 55.7% and 65.7% for both H2O splitting and CO2 splitting at 2000 °C. An efficient O2 separation method is extremely crucial to achieve high thermodynamic efficiency, especially in the separation efficiency range of 0–20% and in relatively low reaction temperatures. This research is also applicable in other isothermal H2O or CO2 splitting systems (e.g., chemical cycling) due to similar thermodynamics.

Polyhalogenated carbazoles (PHCZs), are considered as potential persistent organic pollutants (POPs), which have been frequently detected in the environment. However, the altitudinal distribution characteristics and possible sources of PHCZs in high mountain soils are still unknown. The present study was the first to analyze PHCZs in soil samples collected along the eastern slope of Mt. Qionglai (MQ), the east edge of the Tibetan Plateau. The concentration of ΣPHCZs (based on dry weight) ranges from 14.4 to 107 ng/g (median value of 40.9), which was at high end of the range reported in soils and sediments to date in the literature. The composition profiles of PHCZs in the soils of MQ were dominated by 3,6-dichlorocarbazole (36-CCZ), 3-chlorocarbazole (3-CCZ), and 2-bromocarbazole (2-BCZ). The mean TOC-normalized concentrations of ΣPHCZs in soil samples from below-treeline (2092 ng/g TOC) were higher than those from alpine meadow (1124 ng/g TOC), probably due to the forest filter effect. The decreasing trend of the PHCZs TOC-normalized concentrations with altitude shows that accumulation of PHCZs from the alpine meadow samples was not affected by the mountain cold-trapping effect. Significantly positive correlations were observed between the concentrations of more than half of detected PHCZ congeners and TOC. In addition, PHCZs show the potential to represent a class of POPs with the frequent occurrence and wide distribution, as the abundance and environmental behavior of PHCZs are similar to some POPs in MQ.

Practical applications of lithium–sulfur batteries have been impeded by their poor cycling stability that results from the “shuttling” of polysulfides. Herein, we demonstrate a new strategy for developing a hierarchical phosphorus-doped graphene/carbon nanofiber/sulfur aerogel (PGCNF/S) with “network” morphologies, in which sulfur spheres are wrapped with graphene sheets and carbon nanofibers (PGCNFs) with “net” structures and this carbon matrix has greatly improved the electrochemical performances of sulfur spheres. PGCNF nets ensure a uniform loading of sulfur spheres that leads to a high sulfur mass loading of 85 wt%. Also, the good porous structures achieved with this PGCNF/S cathode can provide sufficient space for volume expansion of active sulfur spheres. Due to its structural advantages, this binder-free PGCNF/S cathode exhibits a specific capacity of 1360 mA h g−1 at 0.1C, and a high areal capacity of 21.5 mA h cm−2 based on a high sulfur mass loading of 15.8 mg cm−2. Furthermore, a long term cycling stability of 600 cycles has been achieved by this PGCNF/S cathode with an average coulombic efficiency of ∼99.8%. This work highlights a broadly adaptable strategy of “network” structures for developing scalable and high-energy density electrode materials for energy storage devices.

The research status of wireless monitoring system for structural durability of industrial high-rise buildings is analysed. The factors affecting structural durability of industrial high-rise buildings, such as natural environment and industrial production environment, are deeply researched. The monitoring parameters of wireless monitoring system for structural durability of industrial high-rise buildings are determined. The design of the topology structure of the wireless monitoring network for structural durability of industrial buildings has been completed, and the design objectives of the topology control and power control of the wireless monitoring network for structural durability have been elaborated in depth. The system can realize visual analysis of durability data of industrial high-rise buildings and storage management of cloud servers.

This report outlines a versatile high-performance electrochemiluminescence (ECL) enzyme-linked immunosorbent assay (ELISA) platform, which combines the merits of high-quantum-yield Au nanocluster (AuNC) probe-based ECL technology, the efficient ECL-resonance energy-transfer (ECL-RET) strategy, and highly sensitive and specific ELISA technology. The ECL detection procedure was performed on a recyclable MnO2/AuNC-modified glassy carbon electrode interface by taking advantage of the ECL-RET between the AuNC probe and MnO2 nanomaterials (NMs) to quench the ECL intensity. The etching of MnO2 NMs by the product of ALP-based ELISA recovers the ECL signal. Notably, the ELISA process and the ECL detection procedure in this system are independent. Thus, the ECL-ELISA system can effectively avoid the influence of complex biological samples, and the ECL efficiency of the AuNC probe can be used readily. As demonstrated on TNF-α, because of the abovementioned characteristics, the ECL-ELISA platform presented an extremely wide dynamic range, with a detection limit of 2 orders lower than ELISA. Moreover, the system was also applicable for ultrahigh sensitive detection of various disease-related proteins and able to detect trace biomarkers in real serum samples. Therefore, this multifunctional ECL assay platform is versatile, facile, ultrasensitive, recyclable, and sufficiently straightforward for trace biomarker detection in complex biological samples. This approach not only enriches the foundational study of ECL devices but also greatly expands the potential application of ECL sensors in biological testing and clinical high-throughput diagnosis.

Nanotransfer printing (nTP) technology can generate highly functional three-dimensional (3D) nanostructures in a low-cost and high-throughput fashion. Nevertheless, the fabrication yield and quality of the transferred nanostructures are often limited by the merging of the surface patterns of replica stamps during transfer printing. Here, an nTP technology was developed to fabricate large-area and crack-free 3D multilayer nanostructures. Instead of directly depositing materials on the patterned flexible stamp in conventional nTPs, we transferred the nanostructures straightforwardly onto an attached polydimethylsiloxane slab by removing a sacrificial water-soluble poly(acrylic acid) film, which can avoid the cracking of metal film and the failures of printing nanostructures onto target substrates. Based on this approach, subwavelength-thick polarization rotators working at infrared wavelengths were fabricated. Excellent performance of linear polarization rotation over a broadband was realized. This nTP approach could complement existing fabrication techniques and benefit the development of various functional nanostructures with complex multilayer hierarchies.

Metasurfaces based on resonant subwavelength photonic structures enable novel ways of wavefront control and light focusing, underpinning a new generation of flat-optics devices1. Recently emerged all-dielectric asymmetric metasurfaces, composed of arrays of metaunits with broken in-plane inversion symmetry2–7, exhibit high-quality resonances originating from the intriguing physics of bound states in the continuum. Here, we combine dielectric metasurfaces and hyperspectral imaging to develop an ultrasensitive label-free analytical platform for biosensing. Our technique can acquire spatially resolved spectra from millions of image pixels and use smart data-processing tools to extract high-throughput digital sensing information at the unprecedented level of less than three molecules per μm2. We further show spectral data retrieval from a single image without using spectrometers, enabled by our unique sensor design, paving the way for portable diagnostic applications. This combination of nanophotonics and imaging optics extends the capabilities of dielectric metasurfaces to analyse biological entities and atomic-layer-thick two-dimensional materials over large areas. Spatially resolved spectra from millions of pixels and information extraction from three molecules per μm2 is now possible using dielectric metasurfaces.

Hydrogen production by methane reforming reaction in membrane reactors is a promising means of solar energy harvesting and storage. The integration of endothermic methane reforming with selective removal of H2 through hydrogen permeation membrane theoretically enables a near-complete conversion of methane at the temperature of 400 °C or above (normally 800–900 °C) by shifting the equilibrium of reforming reaction. Operation of methane membrane reforming reactors at lower temperatures offers a special advantage of possible combination with solar trough collector on a large scale. However, such advantages are not immediately apparent due to special characteristics of solar thermal technologies and lower conversion rates of methane, which needs further clarification from a thermodynamic perspective. In this work, a numerical model of solar-driven methane reforming reaction in a palladium (Pd) membrane reactor with vacuum pump and compressor is established. Methane reforming and H2 permeation processes are theoretically investigated in a temperature range of 300 °C to 700 °C. An optimal conversion rate range of methane for efficient solar methane membrane reforming is calculated, and the net solar-to-fuel efficiency can reach as high as 38.25% at 400 °C after taking real vacuum pump and compressor efficiencies into account. The findings of this work show feasibility of integrating methane reforming with mid- or low-temperature solar thermal technologies.

An ultrahigh temperature solar processing platform consisting of a High-Flux Solar Simulator (HFSS) and auxiliary equipments is developed to research high-temperature materials and processes. Refractory metals of zirconium (melting point of 1855 °C), niobium (2477 °C) and tantalum (3017 °C) were successfully melted by concentrated light from xenon lamps of the HFSS. The melting experiment was monitored by a charge-coupled device camera, and the temperature was recorded by a near-infrared multi-wavelength pyrometer. Then the processed metals were examined by SEM and EDS to compare the difference before and after the ultrahigh-temperature experiments. In addition, a numerical model combining Monte-Carlo ray-tracing method and finite-element method was established to simulate the melting process, the results of which agreed well with experimental results. Furthermore, melting temperatures measured by the well-calibrated near-infrared multi-wavelength pyrometer were close to the melting points of the refractory metals (i.e., ±2% relative error). The experimental platform also demonstrates the capability of providing high radiative flux and ultrahigh temperatures (>2000 °C) for the calibration of heat flux gauges and the testing of high-temperature properties of materials. The concentrated solar energy based ultrahigh temperature technology provides an innovative approach for processing refractory materials in general.