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Copper-based halides have been found to be a new family of lead-free materials with high stability and superior optoelectrical properties. In this work, we report the photoluminescence of the known (C8H14N2)CuBr3and the discovery of three new compounds, (C8H14N2)CuCl3, (C8H14N2)CuCl3·H2O, and (C8H14N2)CuI3, which all exhibit efficient light emissions. All these compounds have monoclinic structures with the same space group (P21/c) and zero-dimensional (0D) structures, which can be viewed as the assembly of promising aromatic molecules and different copper halide tetrahedrons. Upon the irradiation of deep ultraviolet light, (C8H14N2)CuCl3, (C8H14N2)CuBr3,,and (C8H14N2)CuI3show green emission peaking at ∼520 nm with a photoluminescent quantum yield (PLQY) of 3.38, 35.19, and 17.81%, while (C8H14N2)CuCl3·H2O displays yellow emission centered at ∼532 nm with a PLQY of 2.88%. A white light-emitting diode (WLED) was successfully fabricated by employing (C8H14N2)CuBr3as a green emitter, demonstrating the potential of copper halides for applications in the green lighting field.

Recently, much effort has gone into developing travel technology aids in indoor scenes, intending to increase the autonomy and quality of life of partially sighted or visually impaired (PSVI) people. However, existing indoor navigation methods require accurate prior maps. Yet, such maps are not always available and often difficult for people, especially the PSVI, to acquire or construct on site in real-time. To tackle such important issue, this work proposes a topological semantic mapping method for the PSVI such that they can well navigate such indoor environment as hospitals. The distinctive feature of this approach is its utilization of nonstandard floor plans, which can be easily obtained from real-world settings, as the primary data source. The proposed method that generating a sparse topological semantic map (TSM) from a floor plan includes: 1) preprocessing of captured floor plan images to extract a map area and correct a map view; 2) segmentation of an accessible area through a proposed text-based unsupervised image segmentation (TUIS) network; and 3) node calculation and semantic matching. Experimental results demonstrate the validity of the constructed TSM as well as TUIS’s superiority to existing methods.

The simultaneous analysis of diversified biomarkers with high sensitivity and in a point-of-care (POC) manner is of great significance for facile and early cancer diagnosis. Herein, we develop a target amplification-assisted ratiometric fluorescence assay (TARFA) platform integrating the dual-amplification strategy and colorimetric readout technology for sensitive and specific detection of two malignancy-associated biomarkers. Meanwhile, the NIR-excited alkaline-earth sulfide nanodots (ASNDs) with an ultrasmall (<10 nm) diameter and tunable emission wavelength are employed to replace commonly UV/visible light-excited fluorescent labels to minimize background interference from the sample matrix. Unique advantages of the ASNDs, together with superiority of consecutive signal amplification of enzymatic target recycling (ETR) and hybridization chain reaction (HCR), realize the pg/mL-range detection limit in specifically recognizing the vascular endothelial growth factor (VEGF) and soluble interleukin-6 receptors (sIL-6R). The combination detection of the dual analyte exhibits an improved sensitivity for cancer diagnosis. The addition of the target biomarkers leads to an increasingly ratiometric RGB signal, and quantification based on the ratio-dependent signal is more reliable rather than measuring the absolute RGB signals. Moreover, perceptible color transformation makes the TARFA platform competent for visual analysis of the target analytes as convenient as reading the pH indicator strip, and hue-based image analysis also improves the method with fine precision by quantitatively identifying the visual color. This work provides a new kind of NIR-excited aptasensing platform with a low detection limit, high throughput, and great portability, which also highlights the potential of the ASNDs in biomolecular fluorescent labeling.

This paper presents a detailed study of the influence of yttrium (Y) concentration on thermally stimulated luminescence (TSL) of LYSO:Ce crystals and establishes the relationship between electron traps and scintillation properties. With the increase of Y concentration, the glow curve shifts toward higher temperatures and the trap depth increases gradually. Our results revealed two groups of electron traps with one shallow (Et≈ 0.10–0.26 eV) and one deep (Et≈ 1.00–1.21 eV). Our TSL results suggest that the amount of shallow traps varied with Y content has a positive correlation with energy resolution, while the amount of deep traps is inversely proportional to light output. In order to analyze the variation trend of trap depths and their mechanism in detail, we calculated the band gap with the PBE functional and VUV excitation spectra. The results show that the increase of band gap possibly leads to the increase of deep electron trap depth.

Succinonitrile (SN)-based polymer plastic crystal electrolytes (PPCEs) have attracted considerable attention as solid-state electrolytes owing to their high ionic conductivities similar to those of liquid electrolytes, excellent contacts with the electrodes, and good mechanic properties. As a crucial property of a solid-state electrolyte, the ionic conductivity of the PPCE directly depends on the interactions between the constituent parts including the polymer, lithium salt, and SN. A few studies have focused on the effects of polymer–lithium–salt and polymer–SN interactions on the PPCE ionic conductivity. Nevertheless, the impact of the lithium–salt–SN combination on the PPCE ionic conductivity has not been analyzed. In particular, tuning of the lithium-salt–SN interaction to fabricate a subzero PPCE with a high low-temperature ionic conductivity has not been reported. In this study, we design and fabricate five PPCE membranes with different weight ratios of LiN(SO2CF3)2(LiTFSI) and SN to investigate the effect of the LiTFSI–SN interaction on the PPCE ionic conductivity. The ionic conductivities of the five PPCEs are investigated in the temperature range of –20 to 60 °C by electro-chemical impedance spectroscopy. The interaction is analyzed by Fourier-transform infrared spectroscopy, Raman spectroscopy, and differential scanning calorimetry. The LiTFSI–SN interaction significantly influences the melting point of the PPCE, dissociation of the LiTFSI salt, and thus the PPCE ionic conductivity. By tuning the LiTFSI–SN interaction, a subzero workable PPCE membrane having an excellent low-temperature ionic conductivity (6 × 10−4 S cm–1at 0 °C) is obtained. The electro-chemical performance of the optimal PPCE is evaluated by using a LiCoO2/PPCE/Li4Ti5O12cell, which confirms the application feasibility of the proposed quasi-solid-state electrolyte in subzero workable lithium-ion batteries.

High-energy density solid-state lithium metal batteries are expected to become the next generation of energy storage devices. Polymeric ionic liquid-based solid polymer electrolytes (PIL-based SPEs) are an attractive choice among electrolytes, but their ionic conductivities are generally insufficient due to numerous crystallized polymer regions. To achieve higher conductivity, we use facile copolymerization of an ionic liquid (IL) monomer and poly(ethylene glycol) diacrylate monomer to obtain in situ plasticized polymer chains. The resultant PIL-based SPE exhibits decreased crystallinity, a lower glass-transition temperature, and improved ionic conductivity (1.4 × 10–4S cm–1at 30 °C). A solid-state LiFePO4(LFP)|Li battery based on the SPE displays a high reversible specific capacity of 140 mA h g–1at 0.2C at 25 °C and excellent cycling stability, accompanying high Coulombic efficiency of approximately 100%. The in situ plasticized PIL-based SPE is significant in developing solid-state Li metal battery systems.

Hepatocellular carcinoma (HCC) is a highly malignant tumor that is resistant to chemotherapy and immunotherapy. Icaritin (ICT), a traditional Chinese medicine, has been reported as an immunoregulatory agent for treating advanced unresectable HCC. ICT induces mitophagy to cause immunogenic cell death (ICD); however, the poor bioavailability of ICT limits its therapeutic efficacy and clinical use. Therefore, this study aimed to assess the effect of using the poly(2-(N-oxide-N,N-diethylamino) ethyl methacrylate)-b-poly(ε-caprolactone) copolymer (OPDEA-PCL) to encapsulate ICT into nanoparticles (ICT NPs). OPDEA-PCL/ICT NPs colocalized with the mitochondria, promoting the ICD induction effect of ICT in mouse HCC H22 cells. In the H22 subcutaneous tumor model, intravenously injected OPDEA-PCL/ICT NPs quickly accumulated in the tumor and efficiently activated systemic anticancer immunogenicity through their effects on mitophagy. The resulting tumor suppression rate was 60%, which was significantly higher than that of free ICT and poly(ethylene glycol) (PEG)-PCL/ICT NPs. Furthermore, mouse survival was also prolonged by nearly 2-fold with OPDEA-PCL/ICT NPs compared with PBS. In summary, this approach provides valuable insights into improving the immunotherapeutic efficacy of ICT for HCC.

Efficient catalysts with minimal content of catalytically active noble metals are essential for the transition to the clean hydrogen economy. Catalyst supports that can immobilize and stabilize catalytic nanoparticles and facilitate the supply of electrons and reactants to the catalysts are needed. Being hydrophilic and more conductive compared with carbons, MXenes have shown promise as catalyst supports. However, the controlled assembly of their 2D sheets creates a challenge. This study established a lattice engineering approach to regulate the assembly of exfoliated Ti3C2TxMXene nanosheets with guest cations of various sizes. The enlargement of guest cations led to a decreased interlayer interaction of MXene lamellae and increased surface accessibility, allowing intercalation of Pd nanoparticles. Stabilization of Pd nanoparticles between interlayer-expanded MXene nanosheets improved their electrocatalytic activity. The Pd-immobilized K+-intercalated MXene nanosheets (PdKMX) demonstrated exceptional electrocatalytic performance for the hydrogen evolution reaction with the lowest overpotential of 72 mV (@10 mA cm–2) and the highest turnover frequency of 1.122 s–1(@ an overpotential of 100 mV), which were superior to those of the state-of-the-art Pd nanoparticle-based electrocatalysts. Weakening of the interlayer interaction during self-assembly with K+ions led to fewer layers in lamellae and expansion of the MXene in the cdirection during Pd anchoring, providing numerous surface-active sites and promoting mass transport. In situspectroscopic analysis suggests that the effective interfacial electron injection from the Pd nanoparticles strongly immobilized on interlayer-expanded PdKMX may be responsible for the improved electrocatalytic performance.

Lincomycin (LCM) has low ultraviolet (UV) absorption and thus, its determination requires complex instrumentation. Herein, a novel fluorometric probe based on an europium metal–organic framework coated with molecularly imprinted polymers (Eu(BTC)-MIP) was fabricated for the selective determination of LCM. First, highly luminescent Eu(BTC) was synthesized at room temperature. Then, through a simple co-polymerization process, MIPs were formed on the Eu(BTC) surface in the presence of LCM as template molecules to obtain Eu(BTC)-MIP. Eu(BTC) acted as a supporting substrate and antenna, and the MIP layer provided specific binding sites for LCM. Due to the advantages of both Eu(BTC) and MIPs, the probe had a long emission lifetime, strong fluorescence and specific recognition. Under the optimized conditions, the probe achieved the selective determination of LCM in the concentration range of 10 to 100 μg L−1with a detection limit (LOD) of 7.18 μg L−1(S/N = 3). This method is attractive because of its low cost, good selectivity, ready availability and simple manipulation without the need for complex instrumentation. Furthermore, the probe was successfully employed to detect LCM in egg samples with a recovery in the range of 88.02% to 97.29% and a relative standard deviation (RSD) of less than 3.46%. The satisfactory results demonstrate that the proposed probe based on Eu(BTC)-MIP can be used for the quantitative analysis of LCM and exhibits great potential for LCM determination in food samples. Also this study provides a new perspective for the determination of weak ultraviolet absorption or non-fluorescent substances without conjugated groups.

Donor and acceptor ions serving as extrinsic defects in piezoelectrics are mostly used to improve the performance merits to satisfy the industrial application. However, the conventional doping strategy is unable to overcome the inherent trade-off between the piezoelectric coefficient (d33) and mechanical quality factor (Qm). Herein, inspired by the valence state variation observed in manganese oxides during sintering, this study focuses on manipulating intrinsic oxygen vacancies and extrinsic manganese defects in potassium sodium niobate (KNN) ceramics via heat treatment. The annealing process results in a simultaneous improvement in both d33(20%) and Qm(80%), leading to comparable performance with commercial PZT-5A ceramics and enabling their application in atomizer components. Moreover, the mechanism of manganese occupation and diffusion is proposed by an extended X-ray absorption fine structure and density functional theory analysis. The improved electromechanical performance in the annealed KNN ceramic is associated with the optimized redistribution of acceptor and donor manganese defects, which is facilitated by the recombination of oxygen vacancies. This work breaks longstanding obstacles in comprehending the existing forms of manganese in KNN and offers potential in popularizing KNN-based piezoceramics to replace traditional PZT lead-based counterparts in the industrial market.

SOX2 is a key regulator of multiple types of stem cells, especially embryonic stem cells (ESCs) and neural progenitor cells (NPCs). Understanding the mechanism underlying the function of SOX2 is of great importance for realizing the full potential of ESCs and NPCs. Here, through genome-wide comparative studies, we show that SOX2 executes its distinct functions in human ESCs (hESCs) and hESC-derived NPCs (hNPCs) through cell type- and stage-dependent transcription programs. Importantly, SOX2 suppresses non-neural lineages in hESCs and regulates neurogenesis from hNPCs by inhibiting canonical Wnt signaling. In hESCs, SOX2 achieves such inhibition by direct transcriptional regulation of important Wnt signaling modulators, WLS and SFRP2. Moreover, SOX2 ensures pluripotent epigenetic landscapes via interacting with histone variant H2A.Z and recruiting polycomb repressor complex 2 to poise developmental genes in hESCs. Together, our results advance our understanding of the mechanism by which cell type-specific transcription factors control lineage-specific gene expression programs and specify cell fate.

ABSTRACTβ-Lactamase production is one of the most important strategies for Gram-negative bacteria to combat β-lactam antibiotics. Studies of the regulation of β-lactamase expression have largely been focused on the class C β-lactamase AmpC, whose induction by β-lactams requires LysR-type regulator AmpR and permease AmpG-dependent peptidoglycan recycling intermediates. In Shewanella, which is ubiquitous in aquatic environments and is a reservoir for antibiotic resistance, production of the class D β-lactamase BlaA confers bacteria with natural resistance to many β-lactams. Expression of the blaAgene in the genus representative Shewanella oneidensisis distinct from the AmpC paradigm because of the lack of an AmpR homologue and the presence of an additional AmpG-independent regulatory pathway. In this study, using transposon mutagenesis, we identify proteins that are involved in blaAregulation. Inactivation of mrcAand lpoA, which encode penicillin binding protein 1a (PBP1a) and its lipoprotein cofactor, LpoA, respectively, drastically enhances blaAexpression in the absence of β-lactams. Although PBP1b and its cognate, LpoB, also exist in S. oneidensis, their roles in blaAinduction are dispensable. We further show that the mrcA-mediated blaAexpression is independent of AmpG.

ABSTRACTβ-Lactam antibiotics were the earliest discovered and are the most widely used group of antibiotics that work by inactivating penicillin-binding proteins to inhibit peptidoglycan biosynthesis. As one of the most efficient defense strategies, many bacteria produce β-lactam-degrading enzymes, β-lactamases, whose biochemical functions and regulation have been extensively studied. A signal transduction pathway for β-lactamase induction by β-lactam antibiotics, consisting of the major peptidoglycan recycling enzymes and the LysR-type transcriptional regulator, AmpR, has been recently unveiled in some bacteria. Because inactivation of some of these proteins, especially the permease AmpG and the β-hexosaminidase NagZ, results in substantially elevated susceptibility to the antibiotics, these have been recognized as potential therapeutic targets. Here, we show a contrasting scenario in Shewanella oneidensis, in which the homologue of AmpR is absent. Loss of AmpG or NagZ enhances β-lactam resistance drastically, whereas other identified major peptidoglycan recycling enzymes are dispensable. Moreover, our data indicate that there exists a parallel signal transduction pathway for β-lactamase induction, which is independent of either AmpG or NagZ.

Chemical reactions involve competing pathways. Here, two pathways for H desorption from MgH2are identified by first-principles calculations: One involves H diffusion in bulk Mg, while the other involves H vacancy diffusion at the MgH2surface. The latter is sensitive to the size of the reactant MgH2and self-terminates in bulk material as dehydrogenation eventually eliminates exposed MgH2. However, this surface vacancy pathway can maximize the catalyst effect of Pd by decoupling the kinetics of H desorption from that of H diffusion. When the surface-to-bulk ratio is large as in the case of MgH2nanostructures, H desorption will take place primarily via the low-barrier surface vacancy pathway. Our picture attributes the experimentally observed size effect of MgH2on H desorption, beyond the quantum size regime, to a synergy between the nanosize of the reactant and the catalyst.

Effective treatments to prevent recurrence or progression of non-muscle-invasive bladder cancer, or to inhibit metastasis of muscle-invasive forms of the disease, would deliver significant patient benefit. Here the involvement of STAT signalling and the chemopreventive potential of diindolylmethane (DIM) in human bladder cancer were investigated. Muscle-invasive bladder cancer tissues were characterised by nuclear expression of phosphorylated STAT1, 3 and 5. In E-cadherin positive tumour cell lines (RT112, RT4, HT1376), STAT5 was constitutively phosphorylated, while E-cadherin negative lines (J82, T24, UMUC3) contained phosphoSTAT3. Knockdown of STAT3 induced G0/G1 arrest and inhibited adhesion in J82 cells. Knockdown of STAT1inhibited migration in J82 and RT112 lines. No significant increase in apoptosis was observed. In response to the Janus kinase inhibitor, AG490, RT112 and J82 cells initially underwent G0/G1 arrest, with RT112 cells subsequently exhibiting S phase arrest. Phosphorylation of STAT1Tyr701, STAT3Tyr705 and Ser727 and STAT5Tyr694 was inhibited by DIM, as was adhesion of J82 cells to collagen, an effect that was enhanced when STAT1 or 3 was reduced by siRNA. However, over-expression of STAT3C partially rescued the DIM inhibitory effect on collagen-mediated adhesion. Migration of both lines was inhibited by DIM, while transfection of constitutively active STAT3C enhanced migration of RT112 cells. DIM induced cell cycle arrest and apoptosis in three cell lines with different degrees of radioresistance. Taken together, these results suggest that inhibition of STAT signalling and/or treatment with DIM may decrease invasiveness of bladder cancer. DIM can induce apoptosis in cell lines which are radioresistant, so in combination with radiotherapy may be useful in overcoming such resistance.

Sub-10 nm monodisperse alkaline-earth sulfide nanodots (ASNDs) with bright near-infrared (NIR)-excitation fluorescence and adjustable emission wavelength were prepared by a thermal decomposition method for the first time. The ASNDs exhibited high NIR-to-vis conversion efficiency and served as multicolor fluorescent labels in the proposed miR-224 assay. Targeted detection of the miR-224 level and single-nucleotide variation in miR-224 was carried out on a smartphone-based platform using a hybridization chain reaction (HCR) amplification strategy. In the presence of miR-224, the ASND-labeled HCR probes self-assembled on the surface of the diagnosis kits, generating strong fluorescent signals linearly proportional to miR-224 contents in the range of 10–2000 fM. Significantly, mutations in miR-224 led to the variation in the fluorescence intensity ratio in RGB channels. Simultaneously, evident changes of fluorescent brightness and color were easily visualized by the naked eye, which enabled on-site discrimination of miR-224 with different mutant loci. This work provides a novel preparation approach for ultrasmall NIR excitation sulfide nanodots and reveals the potential of the as-synthesized ASNDs in point-of-care (POC) nucleic acid testing. Further, it may provide a handheld platform for miRNA single-nucleotide polymorphism analysis.

The one-dimensional (1D) form of van der Waals (vdW) layered compounds attracts growing interest due to their unusual physical properties and potential for nanoelectronic devices. However, the natural domain structure of vdW layered compounds is generally in a 2D form (nanosheets). Here, we report the high-quality 1D growth of vdW layered SnSe nanoribbons (NRs) via vapor deposition. The morphology evolution of SnSe products was systematically investigated. Angle-resolved polarized Raman spectroscopy and transmission electron microscopy analyses showed that the SnSe NRs are oriented along the [010] (zigzag, ZZ) direction. The intact morphology and good crystallinity suggest that the growth of SnSe NRs obeys a catalysis-free vapor–solid mechanism. Density functional theory calculations unveiled that the minimal migration barrier (0.33 eV) along the ZZ direction and the ZZ-oriented in-plane quasi-1D nature of SnSe are the main driving force of the 1D growth of vdW layered SnSe.