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Lead‐free halide perovskites (LHP) have attracted extensive attention in the field of next‐generation solid‐state lighting. However, single perovskite phosphor with tunable white‐light emission and ultra‐high photoluminescence quantum yield (PLQY) are rare. Here, the tunable dual‐color emission LHP phosphor is developed with a near‐unity PLQY of 99.5%. The LHP phosphor comprises Cs2NaInCl6: Sb3+/Bi3+ and Cs2InCl5·H2O: Sb3+/Bi3+ crystals, with the transition between these two perovskite structures being adjustable by the concentration of Na+. The addition of NaCl inhibits the hydrolysis of the [Sb(H2O)Cl5]2− octahedron, resulting in 3D connected [SbCl6]3− octahedron with less Jahn‐Teller distortion, and the PLQY of LHP is greater than 90%. Finally, the white‐light diode device is fabricated by assembling the LHP with a ultraviolet light‐emitting diode  chip and the white light‐emitting diode device achieved Commission Internationale de l'Eclairage color coordinates of (0.34, 0.33), correlated color temperature of 4936 K, and a high color rendering index of 92.9. The LHP perovskite exhibited multimodal luminescence when excited by 365, 335, and 310 nm UV light, showing the multi‐mode anti‐counterfeiting capabilities of the LHP crystals. [ABSTRACT FROM AUTHOR]

Metal halide perovskite (MHP) single crystals (SCs) have been demonstrated to have significant potential in photodetectors and photovoltaic devices due to their exceptional optoelectronic properties. The most promising approach for large-scale fabrication of high-quality MHP SCs is the synthesis of MHP SCs in solution. To explain the mechanism and guide the crystal growth process, the classical nucleation-growth theory was established. However, it mainly focuses on zone melting systems and does not account for the interaction between perovskite and solvent. In this review, we specifically focus on the difference in the growth mechanism between MHP SCs in solution and traditional SCs synthesized by the melting method, which includes a discussion of the dissolution, nucleation, and growth processes. We then summarize recent advances in the preparation of MHP SCs based on the special growth mechanism of the perovskite system. The purpose of this review is to provide comprehensive information to offer targeted theoretical guidance as well as unified understanding for the preparation of high-quality MHP SCs in solution. [ABSTRACT FROM AUTHOR]

Glass scintillators have several benefits compared to the currently used single or polycrystalline scintillators, including non‐hygroscopicity, mechanical ruggedness, ease of producing customizable shapes, and low‐cost synthesis. The combination of the inert glass matrix and the embedded highly scintillating center render them significant materials for medical imaging and therapy, non‐destructive probing, nuclear monitoring, and high‐energy physics. Recently, great progress has been made in exploring new kinds of glass scintillator materials, improving imaging resolution for radiation detection, and developing an enormous range of commercial products. However, the majority of efforts have been devoted to the variation of materials, while rationally designing this new family of scintillators toward expected properties and applications is still lacking. In this review, the focus is specifically on advances in glass scintillators, including the scintillation fundamentals, material designing rule, and current application status, as well as future challenges and future directions. [ABSTRACT FROM AUTHOR]

Infrared evanescent wave sensing based on chalcogenide fiber is an emerging technology for qualitative and quantitative analysis of most organic compounds. Here, a tapered fiber sensor made from Ge10As30Se40Te20 glass fiber was reported. The fundamental modes and intensity of evanescent waves in fibers with different diameters were simulated with COMSOL. The 30 mm length tapered fiber sensors with different waist diameters, 110, 63, and 31 μm, were fabricated for ethanol detection. The sensor with a waist diameter of 31 μm has the highest sensitivity of 0.73 a.u./% and a limit of detection (LoD) of 0.195 vol.% for ethanol. Finally, this sensor has been used to analyze alcohols, including Chinese baijiu (Chinese distilled spirits), red wine, Shaoxing wine (Chinese rice wine), Rio cocktail, and Tsingtao beer. It is shown that the ethanol concentration is consistent with the nominal alcoholicity. Moreover, other components such as CO2 and maltose can be detected in Tsingtao beer, demonstrating the feasibility of its application in detecting food additives. [ABSTRACT FROM AUTHOR]

Sensitive and fast detection of neutrons and gamma rays is vital for homeland security, high‐energy physics, and proton therapy. Fast‐neutron detectors rely on light organic scintillators, and γ‐ray detectors use heavy inorganic scintillators and semiconductors. Efficient mixed‐field detection using a single material is highly challenging due to their contradictory requirements. Here we report hybrid perovskites (C8H12N)2Pb(Br1−xClx)4 that combine light organic cations and heavy inorganic skeletons at a molecular level to achieve unprecedented performance for mixed‐field radiation detection. High neutron absorption due to a high density of hydrogen, strong radiative recombination within the highly confined [PbX6]4− layer, and sub‐nanometer distance between absorption sites and radiative centers, enable a light yield of 41 000 photons/MeV, detection pulse width of 2.97 ns and extraordinary linearity response toward both fast neutrons and γ‐rays, outperforming commonly used fast‐neutron scintillators. Neutron energy spectrum, time‐of‐flight based fast‐neutron/γ‐ray discrimination and neutron yield monitoring were all successfully achieved using (C8H12N)2Pb(Br0.95Cl0.05)4 detectors. We further demonstrate the monitoring of reaction kinetics and total power of a nuclear fusion reaction. We envision that molecular hybridized scintillators open a new avenue for mixed‐field radiation detection and imaging. [ABSTRACT FROM AUTHOR]

Thanks to its strong X‐ray absorption and large carrier diffusion length, perovskites have demonstrated excellent performance for X‐ray detection. Combination of perovskite with thin‐film transistor (TFT) arrays to construct flat‐panel X‐ray imager (FPXI) is required for X‐ray imaging, yet this is rarely reported. Solution processing of perovskite thick film onto TFT can enable the electronic connection, however the amounts of pinholes inevitably form during the solvent evaporation and result in a porous film with deteriorated performance and stability. Here a novel strategy is raised to achieve high‐quality perovskite thick films for TFT integration via soft‐pressing and in situ polymerization of multi‐functional binder (TMTA). The combined process largely eliminates the pinholes, improves the surface smoothness, passivates grains boundaries, reduces ionic migration, and improves stability. Accordingly, a compact and smooth MAPbI3 thick film integrating with TFT arrays is prepared for flat‐panel X‐ray imaging. The largest film (28 × 28 cm2) is obtained with the state‐of‐the‐art performance (ratio of sensitivity to noise current: 1.41 × 1011 µC Gy−1 A−1) among polycrystalline films. It is hoped that the work provides guidance for fabricating compact perovskite thick films and push perovskite FPXI one step further for low‐dose X‐ray imaging. [ABSTRACT FROM AUTHOR]

Organic‐inorganic hybrid perovskites have demonstrated excellent performance in converting X‐ray photons to electrical signals with high detectivity and sensitivity. Solution‐processed large‐area perovskite polycrystalline thick film is promising for scalable X‐ray flat panel detection imaging. However, ionic migration is severe due to the numerous grain boundaries and pinholes in the thick films, resulting in a large dark current and serious baseline drift. Herein, a new strategy is proposed to suppress the ion migration by inserting 2D Ruddlesden–Popper layer into the 3D perovskite film. The quasi‐2D perovskite thick films exhibit lower defects density, suppressed ion migration, and higher thermal stability compared to their 3D counterpart. Based on these advantages, the quasi‐2D perovskite‐based X‐ray detector shows a sensitivity of 10 860 µC Gyair−1 cm−2 with a stable dark current and photocurrent response. Impressively, the extra‐low detection limit of 69 nGyair s−1 is the lowest in all those reported polycrystalline film‐based detectors. The quasi‐2D film is believed to be a very promising choice for digital flat detectors for sensitive radiation detection and low‐dose dosimeter. [ABSTRACT FROM AUTHOR]

The key features of lead halide perovskites, including short emission lifetime and excellent luminous efficiency in the green emission region, perfectly match the strict requirements of underwater wireless optical communication (UWOC). However, the poor stability of perovskite nanocrystals (NCs) restricts its application under water and no relevant application research has been reported. Here, extremely stable CsPbBr3 NCs in all‐inorganic amorphous glass synthesized by all‐solid reaction without any organic ligand are reported. The products achieve high photoluminescence quantum yield (70%) as well as excellent stability toward water, thermal treatment (200 °C in air) and intensive laser irradiation (3.6 kW cm−2). The authors also raise that the refraction index could strongly influence the lifetime values according to the oscillator strength of radiative transitions. The large refraction index of the glass matrix enhances the radiative transition rates of CsPbBr3 NCs (decay time 3.22 ns). At last, the first application of perovskite NCs for UWOC is demonstrated, achieving a bandwidth as high as 180 MHz and data rates of 185 Mbps. [ABSTRACT FROM AUTHOR]

Radiation detectors require scintillator materials combining high light yield, short light decay time and high stability. Metal halide perovskite nanocrystals (PNC) with heavy atoms have demonstrated excellent luminescent efficiency and short emission lifetime, which perfectly match the requirements of X-ray scintillators. However, the poor stability of PNC restricts its applications. Here we report stable CsPbBr3 NCs generated in an all-inorganic glass matrix by controlled crystallization. The transparent composite materials demonstrated good luminescence centered at ∼520 nm as well as excellent stability towards water and heat (250 °C in the air) due to the protection role of inorganic glass. The high refractive index of the inorganic glass matrix enhanced the radiative transition rates. With all these features, the PNC glass-ceramic demonstrated good X-ray response and fast decay. The emission intensity of PNC glass-ceramic was half that of the commercial scintillating material Bi4Ge3O12 (BGO) under X-ray irradiation (50 kV) and the decay time (15.2 ns) was one twentieth that of BGO. The excellent performance and the high stability as well as the easily processable nature of glass samples make these composite materials promising candidates for various X-ray detection scenarios such as remote X-ray detection using scintillating glass fibers. [ABSTRACT FROM AUTHOR]

Metal halide perovskites and derivatives exhibit a high sensitivity and low detection limit as direct X‐ray detectors. Inorganic 2D bismuth halide perovskites are promising for X‐ray detections, but have not been reported. Moreover, the quantitative relationship between the structural dimensionality of A3B2X9 perovskites and their compositions has never been investigated, and the underlying mechanism is unclear. Here, the key structural descriptors for 2D A3B2X9 perovskite derivatives are reported: i) octahedral factor μ, 0.377 < μ < 0895; ii) tolerance factor t, 0.8 < t < 1.06; iii) (rA‐0.55)/t < 1.48 Å. Accordingly, a new 2D A3B2X9 perovskite derivative, Rb3Bi2I9, with high X‐ray attenuation coefficients is found. The assembled X‐ray detector exhibits a high μτ product of 2.51 × 10−3 cm2 V−1, good sensitivity for 159.7 μC Gyair−1 cm−2, and a record low detection limit of 8.32 nGyair s−1 among all direct and indirect perovskite X‐ray detectors. The device also exhibits good stability toward external bias and continuous gamma ray radiations (480 000 Gy). This work provides crystal structural insights to rationally design 2D perovskites for new types of radiation detectors. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) organic–inorganic lead halide perovskites have attracted intensive attention for optoelectronic applications. Principally, strain-induced octahedral distortion in these materials may open up new application scope through modulation of carrier transport. However, they have never been explored as strain sensors. Moreover, traditional strain sensors are troubled by their limited sensitivity at a low strain ratio (<20%), which restricts their use to detect barely visible impact damage. Here, for the first time, we assembled a two-dimensional perovskite (C4H9NH3)2PbBr4 into a strain sensor, providing a high sensitivity (gauge factor ∼141) at an ultralow strain ratio of 0.16% and reversible stretchability. BA2PbBr4 has a positive Poisson's ratio, and its carrier mobilities monotonously decrease upon applying strains. As a prototype, we have integrated this BA2PbBr4 strain sensor into a wearable sensor and successfully detected the motion of finger bending and running. [ABSTRACT FROM AUTHOR]

Se2− color centers and CdSe/Cd1−xZnxSe quantum dots (QDs) were formed in silicate glasses, respectively, by carefully adjusting the content of Al2O3. The absorption coefficient and broad visible emission at 400‐700 nm of Se2− color centers increased firstly and then decreased upon increasing concentration of Al2O3 from 0 to 5 mol. %. With 2 mol. % Al2O3 adding, the band edge emission centered at 497 nm from CdSe QDs in glasses was observed after heat treatment. Raman spectra and TEM characterization confirmed the formation of CdSe/Cd1−xZnxSe QDs. The small amount addition of Al2O3 had a significant effect on the formation of Se2− color centers and precipitation of CdSe/Cd1−xZnxSe QDs in glasses due to its complicated effect on the network structure and optical basicity of the glasses. [ABSTRACT FROM AUTHOR]

Abstract: In order to alleviate the effect of the surface defects on the emission properties of quantum dots, copper ions‐doped ZnSe quantum dots (QDs) in the glasses are prepared using melt‐quenching and subsequent thermal annealing methods. For glasses without copper doping, tunable band‐edge emission from ZnSe QDs is achieved. For glasses with copper doping, efficient energy transfer from ZnSe QDs to copper ions is observed, and efficient broad band emission from copper ions is realized at the expense of the band‐edge emission of ZnSe QDs. Absorption spectra, size‐dependent broad‐band emission spectra and electron spin resonance spectra show the cupric ions are doped into the ZnSe QDs. Results reported here shows that doping of transition‐metal ions into semiconductor QDs in glasses is promising for development of high efficient luminescent glasses. [ABSTRACT FROM AUTHOR]

Background: Cigarette smoke is well known to worsen asthma symptoms in asthmatic patients and to make them refractory to treatment, but the underling molecular mechanism is unclear. We hypothesized that cigarette smoke can reduce the expression of HDAC2 in asthma and the process was achieved by activating the PI3K-δ/Akt signaling pathway.We further hypothesized that roxithromycin (RXM) can alleviate the impacts by cigarette smoke. Methods: A murine model of asthma induced by ovalbumin (OVA) and cigarette smoke has been established. The infiltration of inflammatory cells and inflammatory factors was examined in this model. Finally, we evaluated the expression of HDAC2, Akt phosphorylation levels and the effects of RXM treatment on the model described earlier. Results: Cigarette smoke exposure reduced HDAC2 protein expression by enhancing the phosphorylation of Akt in PI3K-δ/Akt signaling pathway. Furthermore, RMX reduced the airway inflammation and improved the level of expression of HDAC2 in the cigarette smoke-exposed asthma mice. Conclusions: This study provides a novel insight into the mechanism of cigarette smoke exposure in asthma and the effects of RXM treatment on this condition. These results may be helpful for treating refractory asthma and emphasizing the need for a smoke-free environment for asthmatic patients. [ABSTRACT FROM AUTHOR]

Background and Aim: Paraneoplastic syndrome is a disease or symptom that is the consequence of cancer in the body but, unlike mass effect, is not due to the local presence of cancer cells. An overlap of two paraneoplastic syndromes secondary to lung cancer in a patient is very rare. In order to improve the diagnosis of two paraneoplastic syndromes secondary to lung cancer, we reported an overlap of two paraneoplastic syndromes secondary to lung squamous carcinoma in a patient. Methods: We reported a case of a 60-year-old male smoker who presentedmultiple erythematous lesions for 6 months with progressive proximal muscular weakness, and developed to dysphonia in 2 months.His chest computed tomography showed a spiculate pulmonary nodule near the hilar in the right upper lobe and mediastinal lymph nodes enlargement. Lung biopsy showed squamous cell carcinoma. The patient's blood test revealed elevated creatine kinase levels. Electromyography results were consistent with moderate myopathy accompanied with a pattern suggestive of Lambert--Eaton myasthenic syndrome. Results: So we made the diagnosis of an overlap of two paraneoplastic syndromes (dermatomyositis and Lambert--Eaton myasthenic syndrome) secondary to lung squamous carcinoma. Conclusion: Recognition of paraneoplastic syndrome is crucial for early diagnosis of lung cancer because up to 80% of patients may present paraneoplastic syndromes before any other direct indication of malignancy. Early diagnosis and treatment of paraneoplastic syndrome is also important because delayed diagnosis may result in rapid disease progression and irreversible neurological damage. [ABSTRACT FROM AUTHOR]

Sensitive and fast detection of neutrons and gamma rays is vital for homeland security, high‐energy physics and proton therapy. However, efficient mixed‐field detection using a single material is highly challenging because fast‐neutron detectors rely on light organic scintillators, and γ‐ray detectors use heavy inorganic scintillators and semiconductors. In the cover, the authors (DOI: 10.1002/inf2.12325) illustrate organic‐inorganic hybrid perovskites that combine light organic cations and heavy inorganic skeletons at a molecular level to achieve unprecedented performance for mixed‐field radiation detection, so as to obtain the time information and energy information of the nuclear reaction process accurately. [ABSTRACT FROM AUTHOR]

Er3+ ions-doped germano-gallate oxyfluoride glass-ceramic containing BaF2 nanocrystals was prepared through conventional melt quenching and subsequent thermal treatment method. X-ray diffraction patterns and transmission electron microscope images confirmed the formation of BaF2 nanocrystals in glass-ceramics. Preferential incorporation of Er3+ ions into the BaF2 nanocrystals were confirmed by the absorption spectra and emission spectra, and enhanced upconversion emission and infrared emission were observed. Relatively high transmittance in the mid-infrared region indicated great potential of this germano-gallate oxyfluoride glass-ceramics as host materials for the efficient mid-infrared emission from rare-earth ions. [ABSTRACT FROM AUTHOR]

[Display omitted] Lung cancer is the primary cause of cancer-related mortality worldwide. The anticancer effect of stilbene has been noted in various tumor types. GMQ3, which has a stilbene-mimicking skeleton, is a novel small-molecule compound with promising antitumor activity. Our results revealed that GMQ3 not only suppressed cell proliferation and cell migration of lung cancer cells but also led to G1 phase cell cycle arrest and triggered caspase-dependent apoptosis. Furthermore, investigation of the molecular mechanism showed that GMQ3 could inhibited proliferation and induced apoptosis via the p38-MAPK/SIRT1 pathway both in vitro and in vivo. Xenograft tumor mouse models showed that GMQ3 significantly inhibited tumor growth in vivo without affecting body weight. Our findings indicated that GMQ3 exerts a strong anticancer action by suppressing cell proliferation, inhibiting cell migration and inducing cell apoptosis. Moreover, the efficacy of GMQ3 was enhanced in the presence of CDK4/6 inhibitor Abemaciclib. We conclude that GMQ3 is a promising agent with potential for lung cancer. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs)‐embedded inorganic glasses combine the outstanding luminescent properties of QDs with the chemical, mechanical, and thermal stability of glasses, overcoming the instability bottleneck of QDs and facilitating their wide and endurable applications such as nonlinear optical devices, light emission, and signal amplification in the fiber‐optic communication system. Typical QDs incorporated into glasses include IIB‐VIA (e.g., ZnO, CdSe), IVB‐VIA (e.g., PbS), and halide perovskite (CsPbBr3, et al.) QDs. Here, the preparation methods and growth kinetics of QDs in glasses are first discussed, followed by the summary of the optical properties and application explorations of IIB‐VIA, IVB‐VIA, and halide perovskite QDs‐embedded glasses. Finally, research directions to overcome the major challenges associated with these glasses for ultimate applications are proposed. [ABSTRACT FROM AUTHOR]

CdSe quantum dots (QDs) doped glasses have been widely investigated for optical filters, LED color converter and other optical emitters. Unlike CdSe QDs in solution, it is difficult to passivate the surface defects of CdSe QDs in glass matrix, which strongly suppress its intrinsic emission. In this study, surface passivation of CdSe quantum dots (QDs) by Cd1−xZnxSe shell in silicate glass was reported. An increase in the Se/Cd ratio can lead to the partial passivation of the surface states and appearance of the intrinsic emission of CdSe QDs. Optimizing the heat-treatment condition promotes the incorporation of Zn into CdSe QDs and results in the quenching of the defect emission. Formation of CdSe/Cd1−xZnxSe core/graded shell QDs is evidenced by the experimental results of TEM and Raman spectroscopy. Realization of the surface passivation and intrinsic emission of II-VI QDs may facilitate the wide applications of QDs doped all inorganic amorphous materials. [ABSTRACT FROM AUTHOR]

Background: Roxithromycin (RXM) has been widely used in asthma treatment; however, the mechanism has not been fully understood. The aim of our study was to investigate the underlying mechanism of RXM treatment in mediating the effect of transforming growth factor (TGF)-β1 on airway smooth muscle cells (ASMCs) proliferation and caveolinn-1 expression.Methods: Firstly, the rat ovalbumin (OVA) model was built according to the previous papers. Rat ASMCs were prepared and cultured, and then TGF-β1 production in ASMCs was measured by enzyme-linked immunosorbent assay (ELISA). Moreover, the proliferation of ASMCs was determined using cell counting kit (CCK-8) assay. Additionally, the expressions of caveolin-1, phosphorylated-ERK1/2 (p-ERK1/2) and phosphorylated-AKT (p-AKT) in ASMCs treated with or without PD98059 (an ERK1/2 inhibitor), wortannin (a PI3K inhibitor), β-cyclodextrin (β-CD) and RXM were measured by Western blot. Finally, data were evaluated using t-test or one-way ANOVA, and then a P value < 0.05 was set as a threshold.Results: Compared with normal control, TGF-β1 secretion was significantly increased in asthmatic ASMCs; meanwhile, TGF-β1 promoted ASMCs proliferation (P < 0.05). However, ASMCs proliferation was remarkably inhibited by RXM, β-CD, PD98059 and wortmannin (P < 0.05). Moreover, the expressions of p-ERK1/2 and p-AKT were increased and peaked at 20 min after TGF-β1 stimulation, and then suppressed by RXM. Further, caveolin-1 level was down-regulated by TGF-β1 and up-regulated by inhibitors and RXM.Conclusion: Our findings demonstrate that RXM treatment inhibits TGF-β1-induced activation of ERK and AKT and down-regulation of caveolin-1, which may be the potential mechanism of RXM protection from chronic inflammatory diseases, including bronchial asthma. [ABSTRACT FROM AUTHOR]

Ho 3+ /Y 3+ co-doped BaF 2 nanocrystals were precipitated in oxyfluoride glasses through conventional melt-quenching and subsequent thermal treatment. X-ray diffraction patterns, transmission electron microscope images and absorption spectra confirmed the incorporation of Ho 3+ /Y 3+ ions into BaF 2 nanocrystals in glass-ceramics. With the gradual substitution of Ho 3+ ions by Y 3+ ions, concentration dependent energy transfer between excited Ho 3+ ions were suppressed and relative emission intensity at 1.2 μm band was enhanced. The maximum emission cross-section calculated was 0.60 × 10 −20 cm 2 in BH1-GC specimen, indicating that Ho 3+ /Y 3+ co-doped glass-ceramics have a great potential for the development of 1.2 μm band gain medium. [ABSTRACT FROM AUTHOR]