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Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X-ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79â nGy â s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.
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OBJECTIVE: To investigate the effect of Notch2 gene knockout in Treg cells on head and neck squamous cell carcinoma (HNSCC) in mice. METHODS: A mouse model of HNSCC was constructed. Flow cytometry and immunofluorescence were used to examine the numbers of related immune cells and programmed cell death in tumor cells in the spleen and tumor microenvironment of mice. Western blotting was used to measure the expression of related proteins in tumor tissues. RESULTS: The tumor volume of regulatory T (Treg) cell-specific Notch2-knockout mice (experimental group) was significantly smaller than that of control mice (control group) (P < 0.05). Compared with those in the control group, the number of Treg cells and the expression of Ki67 in Treg cells in the spleen and tumor tissue were significantly decreased in the experimental group, while the numbers of CD45+ hematopoietic cells, CD4+ T cells, CD8+ T cells, T helper 1 (Th1) cells, CD11b+ cells (macrophages), and CD11b+CD11c+ cells (dendritic cells) and the expression of Ki67 in CD4+ T cells and CD8+ T cells were significantly increased (P < 0.05). There was no significant difference in the number of Th2 cells between the two groups (P > 0.05). Immunofluorescence analysis showed that the numbers of CD4+ T cells and CD8+ T cells in the tumor tissue in the experimental group were significantly higher than those in the control group (P < 0.05). Compared with that in the control group, programmed cell death in the experimental group was significantly increased (P < 0.05). Moreover, the expression levels of NLRP3, Caspase-1 and GSDMD in the tumor tissues of the experimental group were higher than those in the control group (P < 0.01), while the expression levels of BCL2, Bax, ATG5, LC3 and p62 were not significantly different (P > 0.05). CONCLUSIONS: Specific knockout of the Notch2 gene in Treg cells significantly decreases the function of Treg cells, inhibits the growth of HNSCC and improves the immune microenvironment in mice, thus effectively treating HNSCC.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Receptor Notch2 , Animales , Ratones , Carcinoma de Células Escamosas/metabolismo , Proliferación Celular , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/metabolismo , Antígeno Ki-67/metabolismo , Ratones Noqueados , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Linfocitos T Reguladores , Microambiente Tumoral , Receptor Notch2/genética , Receptor Notch2/metabolismoRESUMEN
OBJECTIVES: This study aimed to explore the relationship between social isolation and sleep in later life and the role of loneliness in this relationship. METHODS: In Study 1, we conducted a cross-sectional analysis of the correlation between social isolation and sleep in community-dwelling older adults (N = 108). This relationship was assessed using subjective and objective measures. Moreover, we examined the mediating role of loneliness cross-sectionally (Study 1) and longitudinally (Study 2). Longitudinal study was based on three waves of data from the National Scale Life, Health, and Aging Project (N = 1, 554). RESULTS: The results showed that social isolation was robustly associated with sleep in the general population of older adults. Specifically, subjective social isolation was associated with subjective sleep, and objective social isolation was associated with objective sleep. The results of the longitudinal study showed that loneliness mediated the reciprocal link between social isolation and sleep across time after controlling for autoregressive effects and basic demographics. CONCLUSIONS: These findings address the gap in the literature on the link between social isolation and sleep in older adults, extending the understanding of improvement in older adults' social networks, sleep quality, and psychological well-being.
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Soledad , Aislamiento Social , Humanos , Anciano , Estudios Transversales , Estudios Longitudinales , Aislamiento Social/psicología , Soledad/psicología , SueñoRESUMEN
Glass is a group of materials with appealing qualities, including simplicity in fabrication, durability, and high transparency, and they play a crucial role in the optics field. In this paper, a new organic-inorganic metal halide luminescent glass exhibiting >78 % transmittance at 506-800â nm range together with a high photoluminescence quantum yield (PLQY) of 28.5 % is reported through a low-temperature melt-quenching approach of pre-synthesized (HTPP)2 MnBr4 (HTPP=hexyltriphenylphosphonium) single crystal. Temperature-dependent X-ray diffraction, polarizing microscopy, and molecular dynamics simulations were combined to investigate the glass-crystal interconversion process, revealing the disordered nature of the glassy state. Benefiting from the transparent nature, (HTPP)2 MnBr4 glass yields an outstanding spatial resolution of 10â lp mm-1 for X-ray imaging. The superb optical properties and facility of large-scale fabrication distinguish the organic-inorganic metal halide glass as a highly promising class of materials for optical devices.
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Current X-ray imaging scintillators are dominated by inorganic scintillators grown through a high-temperature process. Exploring new types of scintillators with mild growth conditions, high light yields, and eco-friendly chemical compositions is essential and challenging. Herein, the zero-dimensional large-area laminar organic-inorganic hybrid metal halide TEA2MnI4 (TEA = tetraethylammonium) single crystal with dimensions of 50 mm × 60 mm × 0.82 mm is grown via a local-heating solvent evaporation method. Compared with its Cl- and Br-based counterparts, the incorporation of the iodine component enhances the X-ray attenuation ability and significantly accelerates the decay of the photoluminescence of TEA2MnI4. Interestingly, the prepared TEA2MnI4 exhibits a high transmittance of >90% over the range of 515-765 nm and exhibits a high light yield of 26288 photons/MeV, which provides the prerequisite for high-resolution X-ray imaging. The TEA2MnI4 single-crystal scintillator displays an astonishing spatial resolution exceeding 25 line pairs per millimeter, which provides a design concept for a Mn-I-based single crystal for high-performance scintillator applications.
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Though fluorescence-tag-based anti-counterfeiting technology has distinguished itself with cost-effective features and huge information loading capacity, the clonable decryption process of spatial-resolved anti-counterfeiting cannot meet the requirements for high-security-level anti-counterfeiting. Herein, we demonstrate a spatial-time-dual-resolved anti-counterfeiting system based on new organic-inorganic hybrid halides BAPPZn2 (Cly Br1-y )8 (BAPP=1,4-bis(3-ammoniopropyl)piperazinium, y=0-1) with ultra-long room-temperature phosphorescence (RTP). Remarkably, the afterglow lifetime can be facilely tuned by regulating the halide-induced heavy-atom effect and can be identified by the naked eyes or with the help of a simple machine vision system. Therefore, the short-lived unicolor fluorescence and lasting-time-tunable RTP provide the prerequisites for unicolor-time-resolved anti-counterfeiting, which lowers the decryption-device requirements and further provides the design strategy of advanced portable anti-counterfeiting technology.
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Low-dimensional organic-inorganic metal halides have recently emerged as a class of promising luminescent materials. However, the intrinsic toxicity of lead would strongly hamper future application. Herein, we synthesized a new type of lead-free zero-dimensional (0D) antimony-based organic-inorganic metal halide single crystals, (PPZ)2SbCl7·5H2O (PPZ = 1-phenylpiperazine), which features a broadband emission at 720 nm. Ultrafast transient absorption and temperature-dependent photoluminescence (PL) spectra are combined to investigate the PL mechanism, revealing that self-trapped exciton recombination was involved. Furthermore, it is interesting that (PPZ)2SbCl7·5H2O material shows reversible PL emission transformation between red light (720 nm) and yellow light (590 nm) as water molecules are inserted or removed from the lattice. Such reversible emission transformation phenomenon renders the (PPZ)2SbCl7·5H2O as a potential low-cost water sensing material.
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Although single-source white emissive perovskite has emerged as a class of encouraging light-emitting material, the synthesis of lead-free halide perovskite materials with high luminous efficiency is still challenging. Here, we report a series of zero-dimensional indium-antimony (In/Sb) alloyed halide single crystals, BAPPIn2-2x Sb2x Cl10 (BAPP = C10H28N4, x = 0 to 1), with tunable emission. In BAPPIn1.996Sb0.004Cl10, bright yellow emission with near 100% photoluminescence quantum yield (PLQY) is yielded when it was excited at 320 nm, which turns into bright white-light emission with a PLQY of 44.0% when excited at 365 nm. Combined spectroscopy and theoretical studies reveal that the BAPP4+-associated blue emission and inorganic polyhedron-afforded orange emission function as a perfect pair of complementary colors affording white light in BAPPIn1.996Sb0.004Cl10 Moreover, the interesting afterglow behavior, together with excitation-dependent emission property, makes BAPPIn2-2x Sb2x Cl10 as high-performance anti-counterfeiting/information storage materials.
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Low-dimensional lead halide perovskite materials recently have drawn much attention owing to the intriguing broadband emissions; however, the toxicity of lead will hinder their future development. Now, a lead-free (C4 H14 N2 )2 In2 Br10 single crystal with a unique zero-dimensional (0D) structure constituted by [InBr6 ]3- octahedral and [InBr4 ]- tetrahedral units is described. The single crystal exhibits broadband photoluminescence (PL) that spans almost the whole visible spectrum with a lifetime of 3.2â µs. Computational and experimental studies unveil that an excited-state structural distortion in [InBr6 ]3- octahedral units enables the formation of intrinsic self-trapped excitons (STEs) and thus contributing the broad emission. Furthermore, femtosecond transient absorption (fs-TA) measurement reveals that the ultrafast STEs formation together with an efficient intersystem crossing has made a significant contribution to the long-lived and broad STE-based emission behavior.
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Exploring high-performance metal-organic frameworks (MOFs) for pseudocapacitors is quite meaningful for energy storage. Herein a bimetal NiCo-MOF with ultrathin thickness was prepared via a simple hydrothermal method, which shows excellent electrochemical performance with specific capacitances of 1945.83 and 1700.40 F/g at current densities of 0.5 and 1 A/g, respectively, while maintaining good stability. X-ray photoelectron spectroscopy and X-ray absorption near-edge spectroscopy spectra unravel that the strong coupling between Ni and Co species enhances the valence state of Ni2+ in the ultrathin nanosheets, which facilitates the charge transfer during the electrochemical reaction and results in greatly improved pseudocapacitive reactivity. This work provides guidance on the promising prospect of MOF materials for pseudocapacitor applications.
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Effective detection of organic/inorganic pollutants, such as antibiotics, nitro-compounds, excessive Fe3+ and MnO4 - , is crucial for human health and environmental protection. Here, a new terbium(III)-organic framework, namely [Tb(TATAB)(H2 O)]â 2H2 O (Tb-MOF, H3 TATAB=4,4',4''-s-triazine-1,3,5-triyltri-m-aminobenzoic acid), was assembled and characterized. The Tb-MOF exhibits a water-stable 3D bnn framework. Due to the existence of competitive absorption, Tb-MOF has a high selectivity for detecting Fe3+ , MnO4 - , 4-nirophenol and nitroimidazole (ronidazole, metronidazole, dimetridazole, ornidazole) in aqueous through luminescent quenching. The results suggest that Tb-MOF is a simple and reliable reagent with multiple sensor responses in practical applications. To the best of our knowledge, this work represents the first TbIII -based MOF as an efficient fluorescent sensor for detecting metal ions, inorganic anions, nitro-compounds, and antibiotics simultaneously.
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The development of efficient MOF-based electrocatalysts with good stability to produce hydrogen is a great challenge in the field of sustainable energy conversion. Herein, we introduced a controlled in-situ sulfurization strategy to generate a highly active and stable hybrid catalyst containing good conductive Fe3S4 ultrasmall nanosheets attached on the surface of 3D MIL-53(Fe) for the hydrogen evolution reaction in acidic solutions.
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Developing high-efficiency and cost-effective electrocatalytic oxygen evolution reaction (OER) catalysts would determine the future distributions of energy conversion technologies. Metal-organic frameworks (MOFs), with unsaturated active metal sites, functionalized organic linkers, and large surface areas, are emerging heterogeneous electrocatalysts for the water oxidation process. Herein, we report an oxygen-evolving microporous (3,10)-connected Co6-based MOF (denoted as CTGU-14) for the electrocatalytic OER. Moreover, the integration of Co-MOF and SnO2, SnO2 (15%) & CTGU-14 composite attains remarkable electrochemical OER performance with a small Tafel slope of 68 mV·dec-1, a positive overpotential of 388 mV at 10 mA·cm-2, and overall durability in an alkali medium. The superior OER activities might be ascribed to more convenient electron transfer from the SnO2 additive to the electrode medium, effective surface area and unsaturated active cobalt centers, and more beneficial delivery for hydroxy radicals in the microporous Co-MOF skeleton in the process of the OER.
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Low-dimensional luminescent lead halide perovskites have attracted tremendous attention for their fascinating optoelectronic properties, while the toxicity of lead is still considered a drawback. Herein, we report a novel lead-free zero-dimensional (0D) indium-based perovskite (Cs2 InBr5 â H2 O) single crystal that is red-luminescent with a high photoluminescence quantum yield (PLQY) of 33 %. Experimental and computational studies reveal that the strong PL emission might originate from self-trapping excitons (STEs) that result from an excited-state structural deformation. More importantly, the inâ situ transformation between hydrated Cs2 InBr5 â H2 O and the dehydrated form is accompanied with a switchable dual emission, which enables it to act as a PL water-sensor in humidity detection or the detection of traces of water in organic solvents.
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Based on the best available activity data at a city level from top down and bottom up methods, a 2013-based emission inventory of NH3 was established for the Henan Province using an emission factors method. The 3 km×3 km spatial gridded distribution was carried out by using GIS technology. The results showed that the total amount of atmospheric NH3 emission in Henan Province in 2013 was 1035.3 kt, and the average emission intensity reached levels of 6.4 t/km2. Livestock and nitrogen fertilizer applications were the top two emission sources, accounting for 52.71% and 31.53% of the total emissions, respectively. Beef, laying hen, and goats were the main contributors in the livestock category, accounting for 34.98%, 16.63%, and 14.02% of the total emissions, respectively. There were different characteristics between emission source contributions and emission intensities in each city. Nanyang, Zhoukou, Shangqiu, and Zhumadian were the prefecture-level cities with large emissions, accounting for 11.53%, 9.84%, 9.62%, and 9.57% of the total amount in Henan Province, respectively. The NH3 emission intensities of Puyang and Louhe were larger than those of other cities, reaching up to 10.7 t·km-2 and 10.2 t·km-2, respectively. The spatial distribution revealed that emissions in the middle eastern region were relatively higher; whereas, the western region emissions were relatively low. The areas with high emissions were concentrated in the plains and densely populated areas.
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Contaminantes Atmosféricos/análisis , Amoníaco/análisis , Animales , Atmósfera , Bovinos , Pollos , China , Ciudades , Femenino , Sistemas de Información Geográfica , Ganado , Análisis EspacialRESUMEN
Two new pyripyropenes, 13-dehydroxy-1,11-deacetylpyripyropene A (1) and 1-deacetylpyripyropene A (2), together with six known compounds, were isolated from a marine fungus Fusarium lateritium 2016F18-1 which was associated with the sponge Phyllospongia foliascens. Their structures were established mainly based on NMR and MS data. Their cytotoxic activities against human cancer cells CNE1, CNE2, HONE1, SUNE1, GLC82, and HL7702 were evaluated.
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Fusarium/química , Piridinas/química , Sesquiterpenos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fusarium/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Conformación Molecular , Piridinas/toxicidad , Sesquiterpenos/toxicidadRESUMEN
OBJECTIVE: To prepare ligustrazine (TMPZ) ocular sustained-release implant, and investigate its in vitro drug release, pharmacokinetics in rabbit vitreum and in vitro correlation. METHOD: Ligustrazine ocular sustained-release implants were prepared by micro-twin conical screw mixers with hot-melting extrusion method, with polyactic-co-glycolic acid (PLGA) as the matrix. HPLC was adopted to determine the concentration in vitreum after ligustrazine was implanted in rabbit eyes, in order to examine its in vivo sustained-release behavior, and study the correlation between in vitro and in vivo. RESULT: Ligustrazine implants were prepared with a drug-loading rate between 10% and 30%, which was in conformity to the pharmacopoeia in terms of the content uniformity. Its in vitro release was in conformity to the zero-order release model. With PLGA 5050, 2. 5A as a vector, ligustrazine implants with a drug-loading rate of 30% could slowly release drug for more than 3 weeks, indicating a good correlation between in vitro and in vivo release. CONCLUSION: Ligustrazine ocular implants prepared with hot-melting extrusion method is practicable. Ligustrazine ocular implants release drug smoothly in rabbit vitreous vitreums, suggesting good sustained-release effect.