Although itch sensation is an important protective mechanism for animals, chronic itch remains a challenging clinical problem. Itch processing has been studied extensively at the spinal level. ...However, how itch information is transmitted to the brain and what central circuits underlie the itch-induced scratching behavior remain largely unknown. We found that the spinoparabrachial pathway was activated during itch processing and that optogenetic suppression of this pathway impaired itch-induced scratching behaviors. Itch-mediating spinal neurons, which express the gastrin-releasing peptide receptor, are disynaptically connected to the parabrachial nucleus via glutamatergic spinal projection neurons. Blockade of synaptic output of glutamatergic neurons in the parabrachial nucleus suppressed pruritogen-induced scratching behavior. Thus, our studies reveal a central neural circuit that is critical for itch signal processing.
Room temperature‐processed electron transport layers (RT‐ETLs) demonstrate vast potential to be used in fabricating high‐performance flexible perovskite solar cells (PSCs) in an energy‐saving manner. ...However, the RT‐ETL normally suffers from inferior crystallinity, mismatched energy level, and high surface trap‐state density, which would result in under‐optimized interfacial electron extraction and undesirable interfacial charge recombination at ETL/perovskite interface, thus limiting the device performance. Herein, a novel strategy is demonstrated to prepare annealing‐free RT‐ETL based on precrystalline metal ion‐modified SnO2 nanocrystals, which perfectly optimizes the interfacial energy level alignment between ETL and perovskite layer, achieving nearly zero‐barrier charge transfer at the interface. As a result, the charge extraction has been remarkably accelerated and the interfacial charge recombination has been largely suppressed, leading to a ≈26% enhancement in device efficiency. The best‐performing flexible PSCs achieve efficiencies up to 19.3%, accompanied by outstanding mechanical strength under repeated bending cycle tests, which, to the best of the knowledge, is one of the highest reported values for the flexible perovskite photovoltaics fabricated with RT‐ETLs.
A combined precrystallization and metal ion surface modification strategy has enabled the room temperature and cost‐effective fabrication of high‐quality SnO2 electron transport layer for effectively accelerating charge extraction and suppressing charge recombination in flexible perovskite photovoltaics, achieving improved efficiencies up to 19.3% and remarkable mechanical strength.
Semiconductor micro/nano‐cavities with high quality factor (Q) and small modal volume provide critical platforms for exploring strong light‐matter interactions and quantum optics, enabling further ...development of coherent and quantum photonic devices. Constrained by exciton binding energy and thermal fluctuation, only a handful of wide‐band semiconductors such as ZnO and GaN have stable excitons at room temperature. Metal halide perovskite with cubic lattice and well‐controlled exciton may provide solutions. In this work, high‐quality single‐crystalline cesium lead halide CsPbX3 (X = Cl, Br, I) whispering‐gallery‐mode (WGM) microcavities are synthesized by vapor‐phase van der Waals epitaxy method. The as‐grown perovskites show strong emission and stable exciton at room temperature over the whole visible spectra range. By varying the halide composition, multi‐color (400–700 nm).WGM excitonic lasing is achieved at room temperature with low threshold (~ 2.0 μJ cm−2) and high spectra coherence (~0.14–0.15 nm). The results advocate the promise of inorganic perovskites towards development of optoelectronic devices and strong light‐matter coupling in quantum optics.
High‐quality cesium lead halide nanoplatelets functioning as whispering‐gallery‐mode microcavities are synthesized by vapor‐phase van der Waals epitaxy method. Multicolor, low‐threshold excitonic lasing action with a high spectra coherence of 0.14–0.15 nm is realized at room temperature. The findings are not only important for developing on‐chip small lasers and high‐speed exciton devices but also promising for fundamental studies in cavity quantum electrodynamics.
Tin‐based perovskite solar cells (Sn‐PSCs) have emerged as promising environmentally viable photovoltaic technologies, but still suffer from severe non‐radiative recombination loss due to the ...presence of abundant deep‐level defects in the perovskite film and under‐optimized carrier dynamics throughout the device. Herein, we healed the structural imperfections of Sn perovskites in an “inside‐out” manner by incorporating a new class of biocompatible chelating agent with multidentate claws, namely, 2‐Guanidinoacetic acid (GAA), which passivated a variety of deep‐level Sn‐related and I‐related defects, cooperatively reinforced the passivation efficacy, released the lattice strain, improved the structural toughness, and promoted the carrier transport of Sn perovskites. Encouragingly, an efficiency of 13.7 % with a small voltage deficit of ≈0.47 V has been achieved for the GAA‐modified Sn‐PSCs. GAA modification also extended the lifespan of Sn‐PSCs over 1200 hours.
Chemical modification of tin perovskites by biocompatible multidentate chelators realized “inside‐out” healing of structural imperfections and manipulation of carrier dynamics, delivering an efficiency up to 13.70 % with enhanced long‐term stability over 1200 h.
Mixed‐cation, small band‐gap perovskites via rationally alloying formamidinium (FA) and methylammonium (MA) together have been widely employed for blade‐coated perovskite solar cells with satisfied ...efficiencies. One of the stringent challenges lies in difficult control of the nucleation and crystallization kinetics of the perovskites with mixed ingredients. Herein, a pre‐seeding strategy by mixing FAPbI3 solution with pre‐synthesized MAPbI3 microcrystals has been developed to smartly decouple the nucleation and crystallization process. As a result, the time window of initialized crystallization has been greatly extended by 3 folds (i.e. from 5 s to 20 s), which enables the formation of uniform and homogeneous alloyed‐FAMA perovskite films with designated stoichiometric ratios. The resultant blade‐coated solar cells achieved a champion efficiency of 24.31 % accompanied by outstanding reproducibility with more than 87 % of the devices showing efficiencies higher than 23 %.
Delaying initialized crystallization and manipulating crystal growth of mixed‐cation alloyed perovskites by pre‐seeding colloidal chemistry realized reproducible fabrication of high‐quality perovskite films with homogenized chemical compositions and improved optoelectronic properties, delivering a record efficiency up to 24.31 % for blade‐coated solar cells with minimized performance variation and extended lifespan.
Lead halide perovskites have emerged as excellent optical gain materials for solution-processable and flexible lasers. Recently, continuous-wave (CW) optically driven lasing was established in ...perovskite crystals; however, the mechanism of low-threshold operation is still disputed. In this study, CW-pumped lasing from one-dimensional CsPbBr3 nanoribbons (NBs) with a threshold of ∼130 W cm–2 is demonstrated, which can be ascribed to the large refractive index induced by the exciton–polariton (EP) effect. Increasing the temperature reduces the exciton fraction of EPs, which decreases the group and phase refractive indices and inhibits lasing above 100 K. Thermal management, including reducing the NB height to ∼120 ± 60 nm and adopting a high-thermal-conductivity sink, e.g., sapphire, is critical for CW-driven lasing, even at cryogenic temperatures. These results reveal the nature of ultralow-threshold lasing with CsPbBr3 and provide insights into the construction of room-temperature CW and electrically driven perovskite macro/microlasers.
Long noncoding RNAs (lncRNAs) have been investigated as novel regulatory molecules involved in diverse biological processes. Our previous study demonstrated that lncRNA‐ES3 is associated with the ...high glucose–induced calcification/senescence of human aortic vascular smooth muscle cells (HA‐VSMCs). However, the mechanism of lncRNA‐ES3 in vascular calcification/aging remained largely unknown. Here, we report that the expression of basic helix‐loop‐helix family member e40 (Bhlhe40) was decreased significantly in HA‐VSMCs treated with high glucose, whereas the expression of basic leucine zipper transcription factor (BATF) was increased. Overexpression of Bhlhe40 and inhibition of BATF alleviated calcification/senescence of HA‐VSMCs, as confirmed by Alizarin Red S staining and the presence of senescence‐associated β‐galactosidase–positive cells. Moreover, we identified that Bhlhe40 regulates lncRNA‐ES3 in HA‐VSMCs by binding to the promoter region of the lncRNA‐ES3 gene (LINC00458). Upregulation or inhibition of lncRNA‐ES3 expression significantly promoted or reduced calcification/senescence of HA‐VSMCs, respectively. Additionally, we identified that lncRNA‐ES3 functions in this process by suppressing the expression of miR‐95‐5p, miR‐6776‐5p, miR‐3620‐5p, and miR‐4747‐5p. The results demonstrate that lncRNA‐ES3 triggers gene silencing of multiple miRNAs by binding to Bhlhe40, leading to calcification/senescence of VSMCs. Our findings suggest that pharmacological interventions targeting lncRNA‐ES3 may be therapeutically beneficial in ameliorating vascular calcification/aging.
In the present study, we identified that long noncoding RNA ES3 (lncRNA‐ES3) binds directly to basic helix‐loop‐helix family member e40 (Bhlhe40), a transcription factor, to regulate calcification/senescence of vascular smooth muscle cells (VSMCs). Additionally, we found that expression of lncRNA‐ES3 in HG‐induced calcified/senescent human aortic VSMCs resulted in suppression of miR‐95‐5p, miR‐6776‐5p, miR‐3620‐5p, and miR‐4747‐5p. Our findings provide potential therapeutic targets for diabetic vascular aging.
Vascular calcification/aging can cause different kind of serious diabetic vascular complications. High glucose could induce vascular smooth muscle cells (VSMCs) calcification/aging and then lead to ...diabetes-related vascular calcification/aging. In this study, we investigated how information in the blood is transmitted to VSMCs and the mechanisms of VSMCs calcification/aging under hyperglycaemic conditions.
Transmission electron microscopy and molecular size analysis were used to assess the morphology and size of exosomes. Alizarin Red S staining and senescence-associated β galactosidase (SA-β-gal) staining were carried out to detect calcification and senescence in VSMCs, respectively. Proteomics analysis was carried out to detect the different expression of exosomal proteins. Protein levels were measured by western blot analysis.
The results show that exosomes isolated from high glucose stimulated human umbilical vein endothelial cell (HG-HUVEC-Exo) exhibited a bilayer structure morphology with a mean diameter of 63.63 ± 2.96 nm. The presence of exosome markers including CD9, CD63 and TSG101 were also detected in HG-HUVEC-Exo. High glucose could induce VSMCs calcification/aging by increasing the expression of osteocalcin (OC) and p21 as well as the formation of mineralised nodules and SA-β-gal positive cells. Fluorescence microscopy verified that the exosomes were taken up by VSMCs and Notch3 protein was enriched in HG-HUVEC-Exo. Most importantly, mTOR signalling was closely related to Notch3 protein and was involved in regulating HG-HUVEC-Exo-induced VSMCs calcification/aging.
The data demonstrate that Notch3 is required for HG-HUVEC-Exo promoted VSMCs calcification/aging and regulates VSMCs calcification/aging through the mTOR signalling pathway.
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Semiconductor nanowires have received considerable attention in the past decade driven by both unprecedented physics derived from the quantum size effect and strong isotropy and advanced applications ...as potential building blocks for nanoscale electronics and optoelectronic devices. Recently, organic–inorganic hybrid perovskites have been shown to exhibit high optical absorption coefficient, optimal direct band gap, and long electron/hole diffusion lengths, leading to high-performance photovoltaic devices. Herein, we present the vapor phase synthesis free-standing CH3NH3PbI3, CH3NH3PbBr3, and CH3NH3PbI x Cl3–x perovskite nanowires with high crystallinity. These rectangular cross-sectional perovskite nanowires have good optical properties and long electron hole diffusion length, which ensure adequate gain and efficient optical feedback. Indeed, we have demonstrated optical-pumped room-temperature CH3NH3PbI3 nanowire lasers with near-infrared wavelength of 777 nm, low threshold of 11 μJ/cm2, and a quality factor as high as 405. Our research advocates the promise of optoelectronic devices based on organic–inorganic perovskite nanowires.
A rapid and convenient homogeneous aptamer sensor with high sensitivity is highly desirable for the electrochemical detection of tumor biomarkers. In this work, a homogeneous electrochemical aptamer ...sensor is demonstrated based on a two-dimensional (2D) nanocomposite probe and nanochannel modified electrode, which can realize sensitive detection of carcinoembryonic antigen (CEA). Using π-π stacking and electrostatic interaction, CEA aptamer (Apt) and cationic redox probe (hexaammineruthenium(III), Ru(NH
)
) are co-loaded on graphite oxide (GO), leading to a 2D nanocomposite probe (Ru(NH
)
/Apt@GO). Vertically ordered mesoporous silica-nanochannel film (VMSF) is easily grown on the supporting indium tin oxide (ITO) electrode (VMSF/ITO) using the electrochemical assisted self-assembly (EASA) method within 10 s. The ultrasmall nanochannels of VMSF exhibits electrostatic enrichment towards Ru(NH
)
and size exclusion towards 2D material. When CEA is added in the Ru(NH
)
/Apt@GO solution, DNA aptamer recognizes and binds to CEA and Ru(NH
)
releases to the solution, which can be enriched and detected by VMSF/ITO electrodes. Based on this mechanism, CEA can be an electrochemical detection ranging from 60 fg/mL to 100 ng/mL with a limit of detection (LOD) of 14 fg/mL. Detection of CEA in human serum is also realized. The constructed homogeneous detection system does not require the fixation of a recognitive aptamer on the electrode surface or magnetic separation before detection, demonstrating potential applications in rapid, convenient and sensitive electrochemical sensing of tumor biomarkers.
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