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1.
Nano Lett ; 24(20): 6084-6091, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717110

RESUMO

Chiral perovskites play a pivotal role in spintronics and optoelectronic systems attributed to their chiral-induced spin selectivity (CISS) effect. Specifically, they allow for spin-polarized charge transport in spin light-emitting diodes (LEDs), yielding circularly polarized electroluminescence at room temperature without external magnetic fields. However, chiral lead bromide-based perovskites have yet to achieve high-performance green emissive spin-LEDs, owing to limited CISS effects and charge transport. Herein, we employ dimensional regulation and Sn2+-doping to optimize chiral bromide-based perovskite architecture for green emissive spin-LEDs. The optimized (PEA)x(S/R-PRDA)2-xSn0.1Pb0.9Br4 chiral perovskite film exhibits an enhanced CISS effect, higher hole mobility, and better energy level alignment with the emissive layer. These improvements allow us to fabricate green emissive spin-LEDs with an external quantum efficiency (EQE) of 5.7% and an asymmetry factor |gCP-EL| of 1.1 × 10-3. This work highlights the importance of tailored perovskite architectures and doping strategies in advancing spintronics for optoelectronic applications.

2.
Sci Total Environ ; 926: 171739, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508259

RESUMO

BACKGROUND: Exposure to ambient ozone pollution causes health loss and even death, and both are the main risk factors for the disease burden worldwide. We comprehensively evaluated the ozone pollution-related disease burden. METHODS: First, numbers and age-standardized rates of deaths and disability-adjusted life years (DALYs) were assessed globally and by sub-types in 2019. Furthermore, the temporal trend of the disease burden was explored by the linear regression model from 1990 to 2019. The cluster analysis was used to evaluate the changing pattern of related disease burden across Global Burden of Disease Study (GBD) regions. Finally, the age-period-cohort (APC) model and the Bayesian age-period-cohort (BAPC) model were used to predict the future disease burden in the next 25 years. RESULT: Exposure to ozone pollution contributed to 365,222 deaths and 6,210,145 DALYs globally in 2019, which accounted for 0.65 % of deaths globally and 0.24 % of DALYs globally. The disease burden was consistently increasing with age. Males were high-risk populations and low-middle socio-demographic index (SDI) regions were high-risk areas. The disease burden of ozone pollution varied considerably across the GBD regions and the countries. In 2019, the number of deaths and DALYs cases increased by 76.11 % and 56.37 %, respectively compared to those in 1990. The predicted results showed that the number of deaths cases and DALYs cases for both genders would still increase from 2020 to 2044. CONCLUSION: In conclusion, ambient ozone pollution has threatened public health globally. More proactive and effective strategic measures should be developed after considering global-specific circumstances.


Assuntos
Carga Global da Doença , Ozônio , Humanos , Masculino , Feminino , Adulto , Anos de Vida Ajustados por Qualidade de Vida , Ozônio/efeitos adversos , Teorema de Bayes , Fatores de Risco , Efeitos Psicossociais da Doença
3.
Nanoscale ; 16(15): 7387-7395, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38545886

RESUMO

Inorganic cesium lead bromide nanocrystals (CsPbBr3 NCs) hold promising prospects for high performance green light-emitting diodes (LEDs) due to their exceptional color purity and high luminescence efficiency. However, the common ligands employed for passivating these indispensable NCs, such as long-chain organic ligands like oleic acid and oleylamine (OA/OAm), display highly dynamic binding and electronic insulating issues, thereby resulting in a low efficiency of the as-fabricated LEDs. Herein, we report a new zwitterionic short-branched alkyl sulfobetaine ligand, namely trioctyl(propyl-3-sulfonate) ammonium betaine (TOAB), to in situ passivate CsPbBr3 NCs via a feasible one-step solution synthesis, enabling efficiency improvement of CsPbBr3 NC-based LEDs. The zwitterionic TOAB ligand not only strengthened the surface passivation of CsPbBr3 NCs with a high photoluminescence quantum yield (PLQY) of 97%, but also enhanced the carrier transport in the fabricated CsPbBr3 NC thin films due to the short-branched alkyl design. Consequently, CsPbBr3 NCs passivated with TOAB achieved a green LED with an external quantum efficiency (EQE) of 7.3% and a maximum luminance of 5716 cd m-2, surpassing those of LEDs based on insulating long-chain ligand-passivated NCs. Our work provides an effective surface passivation ligand design to enhance the performance of CsPbBr3 NC-based LEDs.

4.
J Genet Genomics ; 51(1): 35-47, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37269980

RESUMO

In multicellular organisms, developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree (CLT). The reconstruction of the CLT has long been a major goal in developmental biology and other related fields. Recent technological advancements, especially those in editable genomic barcodes and single-cell high-throughput sequencing, have sparked a new wave of experimental methods for reconstructing CLTs. Here we review the existing experimental approaches to the reconstruction of CLT, which are broadly categorized as either image-based or DNA barcode-based methods. In addition, we present a summary of the related literature based on the biological insight provided by the obtained CLTs. Moreover, we discuss the challenges that will arise as more and better CLT data become available in the near future. Genomic barcoding-based CLT reconstructions and analyses, due to their wide applicability and high scalability, offer the potential for novel biological discoveries, especially those related to general and systemic properties of the developmental process.


Assuntos
Código de Barras de DNA Taxonômico , Genômica , Linhagem da Célula/genética , Genoma
5.
Nat Commun ; 14(1): 5853, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730811

RESUMO

The transcriptional intermediates of RNAs fold into secondary structures with multiple regulatory roles, yet the details of such cotranscriptional RNA folding are largely unresolved in eukaryotes. Here, we present eSPET-seq (Structural Probing of Elongating Transcripts in eukaryotes), a method to assess the cotranscriptional RNA folding in Saccharomyces cerevisiae. Our study reveals pervasive structural transitions during cotranscriptional folding and overall structural similarities between nascent and mature RNAs. Furthermore, a combined analysis with genome-wide R-loop and mutation rate approximations provides quantitative evidence for the antimutator effect of nascent RNA folding through competitive inhibition of the R-loops, known to facilitate transcription-associated mutagenesis. Taken together, we present an experimental evaluation of cotranscriptional folding in eukaryotes and demonstrate the antimutator effect of nascent RNA folding. These results suggest genome-wide coupling between the processing and transmission of genetic information through RNA folding.


Assuntos
Antimutagênicos , Células Eucarióticas , Mutagênese , RNA/genética , Saccharomyces cerevisiae/genética
6.
Chem Soc Rev ; 52(16): 5516-5540, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37482807

RESUMO

Lead halide perovskite nanocrystals are promising for next-generation high-definition displays, especially in light of their tunable bandgaps, high color purities, and high carrier mobility. Within the past few years, the external quantum efficiency of perovskite nanocrystal-based light-emitting diodes has progressed rapidly, reaching the standard for commercial applications. However, the low operational stability of these perovskite nanocrystal-based light-emitting diodes remains a crucial issue for their industrial development. Recent experimental evidence indicates that the migration of ionic species is the primary factor giving rise to the performance degradation of perovskite nanocrystal-based light-emitting diodes, and ion migration is closely related to the defects on the surface of perovskite nanocrystals and at the grain boundaries of their thin films. In this review, we focus on the central idea of surface reconstruction of perovskite nanocrystals, discuss the influence of surface defects on halide ion migration, and summarize recent advances in resurfacing perovskite nanocrystal strategies toward mitigating halide ion migration to improve the stability of the as-fabricated light-emitting diode devices. From the perspective of perovskite nanocrystal resurfacing, we set out a promising research direction for improving both the spectral and operational stability of perovskite nanocrystal-based light-emitting diodes.

7.
Mol Biol Evol ; 40(5)2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37183780

RESUMO

In the same way that a phylogeny summarizes the evolutionary history of species, a cell lineage tree describes the process of clonal expansion, in which gene expression differences between cells naturally accrue as a result of stochastic partitioning and imperfect expression control. How is functional homeostasis, a key factor in the biological function of any population of cells, maintained in the face of such continuous accumulation of transcriptomic heterogeneity remains largely unresolved. To answer this question, we experimentally determined the single-cell transcriptomes and lineage relationships of up to 50% cells in single-HEK293-seeded colonies. Phylogenetic comparative analyses of the single-cell transcriptomes on the cell lineage tree revealed three lines of evidence for the constrained accumulation of transcriptome heterogeneity among cells, including rapid saturation of transcriptomic heterogeneity upon four cell divisions, reduced expression differences within subtrees closer to expression boundaries, and cofluctuations among genes. Our analyses showcased the applicability of phylogenetic comparative methods in cell lineage trees, demonstrated the constrained accumulation of transcriptomic heterogeneity, and provided novel insight into the functional homeostasis of cell populations.


Assuntos
Evolução Biológica , Transcriptoma , Humanos , Filogenia , Células HEK293 , Perfilação da Expressão Gênica
8.
Nano Lett ; 23(8): 3385-3393, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37052258

RESUMO

Lead halide perovskite nanocrystals (LHP NCs) are regarded as promising emitters for next-generation ultrahigh-definition displays due to their high color purity and wide color gamut. Recently, the external quantum efficiency (EQE) of LHP NC based light-emitting diodes (PNC LEDs) has been rapidly improved to a level required by practical applications. However, the poor operational stability of the device, caused by halide ion migration at the grain boundary of LHP NC thin films, remains a great challenge. Herein, we report a resurfacing strategy via pseudohalogen ions to mitigate detrimental halide ion migration, aiming to stabilize PNC LEDs. We employ a thiocyanate solution processed post-treatment method to efficiently resurface CsPbBr3 NCs and demonstrate that the thiocyanate ions can effectively inhibit bromide ion migration in LHP NC thin films. Owing to thiocyanate resurfacing, we fabricated LEDs with a high EQE of 17.3%, a maximum brightness of 48000 cd m-2, and an excellent operation half-life time.

9.
Nature ; 616(7955): 77-83, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37020008

RESUMO

Inorganic superionic conductors possess high ionic conductivity and excellent thermal stability but their poor interfacial compatibility with lithium metal electrodes precludes application in all-solid-state lithium metal batteries1,2. Here we report a LaCl3-based lithium superionic conductor possessing excellent interfacial compatibility with lithium metal electrodes. In contrast to a Li3MCl6 (M = Y, In, Sc and Ho) electrolyte lattice3-6, the UCl3-type LaCl3 lattice has large, one-dimensional channels for rapid Li+ conduction, interconnected by La vacancies via Ta doping and resulting in a three-dimensional Li+ migration network. The optimized Li0.388Ta0.238La0.475Cl3 electrolyte exhibits Li+ conductivity of 3.02 mS cm-1 at 30 °C and a low activation energy of 0.197 eV. It also generates a gradient interfacial passivation layer to stabilize the Li metal electrode for long-term cycling of a Li-Li symmetric cell (1 mAh cm-2) for more than 5,000 h. When directly coupled with an uncoated LiNi0.5Co0.2Mn0.3O2 cathode and bare Li metal anode, the Li0.388Ta0.238La0.475Cl3 electrolyte enables a solid battery to run for more than 100 cycles with a cutoff voltage of 4.35 V and areal capacity of more than 1 mAh cm-2. We also demonstrate rapid Li+ conduction in lanthanide metal chlorides (LnCl3; Ln = La, Ce, Nd, Sm and Gd), suggesting that the LnCl3 solid electrolyte system could provide further developments in conductivity and utility.

10.
Food Funct ; 14(1): 160-170, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36477011

RESUMO

We identified novel antioxidant peptides from Pacific saury (Cololabis saira). Enzymatic hydrolysates were isolated, purified, and identified by ultrafiltration, gel chromatography, reverse phase high-performance liquid chromatography (RP-HPLC), and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS). Twenty putative peptides were identified from five components of HPLC, among which sixteen peptides were predicted to have good water solubility and non-toxicity by online tools. Fifteen peptides were successfully docked with myeloperoxidase, and we observed that Arg31, Arg323, and Lys505 played a key role in the antioxidant mechanism, with van der Waals forces and conventional hydrogen bonds as important interaction forces. Six identified peptides with lower CDOCKER energy values were synthesized to verify the antioxidant activity, and the results showed that the synthetic peptide QQAAGDKIMK displayed the strongest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging rate (31.05 ± 0.27%) and reducing power (0.29 ± 0.01). The synthetic peptide KDEPDQASSK at a concentration of 300 µg mL-1 exhibited the strongest protective effects on H2O2-induced oxidative damage of HEK-293 cells, with cell viability and ROS level of 0.38 ± 0.03 and 0.08 ± 0.01, respectively.


Assuntos
Antioxidantes , Peróxido de Hidrogênio , Humanos , Antioxidantes/química , Peróxido de Hidrogênio/toxicidade , Simulação de Acoplamento Molecular , Células HEK293 , Peptídeos/química , Estresse Oxidativo
11.
J Genet Genomics ; 50(5): 330-340, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36414223

RESUMO

Multiple primary lung cancer (MPLC) is an increasingly prevalent subtype of lung cancer. According to recent genomic studies, the different lesions of a single MPLC patient exhibit functional similarities that may reflect evolutionary convergence. We perform whole-exome sequencing for a unique cohort of MPLC patients with multiple samples from each lesion found. Using our own and other relevant public data, evolutionary tree reconstruction reveals that cancer driver gene mutations occurred at the early trunk, indicating evolutionary contingency rather than adaptive convergence. Additionally, tumors from the same MPLC patient are as genetically diverse as those from different patients, while within-tumor genetic heterogeneity is significantly lower. Furthermore, the aberrant molecular functions enriched in mutated genes for a sample show a strong overlap with other samples from the same tumor, but not with samples from other tumors or other patients. Overall, there is no evidence of adaptive convergence during the evolution of MPLC. Most importantly, the similar between-tumor diversity and between-patient diversity suggest that personalized therapies may not adequately account for the genetic diversity among different tumors in an MPLC patient. To fully exploit the strategic value of precision medicine, targeted therapies should be designed and delivered on a per-lesion basis.


Assuntos
Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Mutação
12.
Environ Pollut ; 316(Pt 2): 120604, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347414

RESUMO

The association between oxidative protein damage in early pregnant women and ambient fine particulate matter (PM2.5) is unknown. We estimated the effect of PM2.5 exposures within seven days before blood collection on serum 3-nitrotyrosine (3-NT) and advanced oxidation protein products (AOPP) in 100 women with normal early pregnancy (NEP) and 100 women with clinically recognized early pregnancy loss (CREPL). Temporally-adjusted land use regression model was applied for estimation of maternal daily PM2.5 exposure. Daily nitrogen dioxide (NO2) exposure of each participant was estimated using city-level concentrations of NO2. Single-day lag effect of PM2.5 was analyzed using multivariable linear regression model. Net cumulative effect and distributed lag effect of PM2.5 and NO2 within seven days were analyzed using distributed lag non-linear model. In all 200 subjects, the serum 3-NT were significantly increased with the single-day lag effects (4.72%-8.04% increased at lag 0-2), distributed lag effects (2.32%-3.49% increased at lag 0-2), and cumulative effect within seven days (16.91% increased). The single-day lag effects (7.41%-10.48% increased at lag 0-1), distributed lag effects (3.42%-5.52% increased at lag 0-2), and cumulative effect within seven days (24.51% increased) of PM2.5 significantly increased serum 3-NT in CREPL group but not in NEP group. The distributed lag effects (2.62%-4.54% increased at lag 0-2) and cumulative effect within seven days (20.25% increased) of PM2.5 significantly increased serum AOPP in early pregnant women before the coronavirus disease (COVID-19) pandemic but not after that, similarly to the effects of NO2 exposures. In conclusion, PM2.5 exposures were associated with oxidative stress to protein in pregnant women in the first trimester, especially in CREPL women. Analysis of NO2 exposures suggested that combustion PM2.5 was the crucial PM2.5 component. Wearing masks may be potentially preventive in PM2.5 exposure and its related oxidative protein damage.


Assuntos
Produtos da Oxidação Avançada de Proteínas , Poluentes Atmosféricos , Poluição do Ar , Material Particulado , Feminino , Humanos , Gravidez , Produtos da Oxidação Avançada de Proteínas/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Estresse Oxidativo , Material Particulado/efeitos adversos , Material Particulado/análise , Gestantes
13.
Sci Adv ; 8(45): eabq2321, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36367940

RESUMO

Solution-processable all-inorganic CsPbI3-xBrx perovskite holds great potential for pure red light-emitting diodes. However, the widely existing defects in this mixed halide perovskite markedly limit the efficiency and stability of present light-emitting diode devices. We here identify that intragrain Ruddlesden-Popper planar defects are primary forms of such defects in the CsPbI3-xBrx thin film owing to the lattice strain caused by inhomogeneous halogen ion distribution. To eliminate these defects, we develop a stepwise metastable phase crystallization strategy to minimize the CsPbI3-xBrx perovskite lattice strain, which brings planar defect-free CsPbI3-xBrx thin film with improved radiative recombination, narrowed emission band, and enhanced spectral stability. Using these high-quality thin films, we fabricate spectrally stable pure red perovskite light-emitting diodes, showing 17.8% external quantum efficiency and 9000 candela meter-2 brightness with color coordinates required by Rec. 2020.

14.
Environ Pollut ; 315: 120446, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36265729

RESUMO

The effect of fine particulate matter (PM2.5) on human early maternal-fetal interface is unknown. We explored the association between maternal exposure to ambient PM2.5 and inflammation in placental villus of 114 women with clinically recognized early pregnancy loss (CREPL) and 114 women with normal early pregnancy (NEP). Temporally-adjusted land use regression models were used to estimate maternal daily PM2.5 exposure during pregnancy. Villus interleukin-1beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were measured using multiplex cytokines detection platform. Single-day lag effect of PM2.5 exposure within ten days before early placental villus collection was estimated using multivariable linear regression model. Distributed lag and net cumulative effects of PM2.5 exposures within ten and 30 days before villus collection, as well as five single weeks during the periovulatory period, were estimated using distributed lag non-linear models. In all 228 subjects, after adjusting for group (CREPL or NEP), temporal confounders, and demographic characteristics, both single-day and distributed lag effects of PM2.5 exposure at lag 8 significantly increased villus IL-6; distributed lag effects of PM2.5 exposure in the first and second weeks before ovulation increased IL-1ß, and PM2.5 exposure in the third week after ovulation increased IL-6 and TNF-α. In CREPL, single-day lag effect significantly increased IL-1ß (at lag 1), IL-6 (at lag 8), and TNF-α (at lag 5); distributed lag effect increased IL-6 (at lag 4-lag 8) and TNF-α (at lag 4-lag 6); and cumulative effect within ten days before villus collection increased IL-6. There was no statistically significant cumulative effect in NEP. In summary, maternal PM2.5 exposure was associated with placental inflammation in human early pregnancy, particularly with increased villus IL-6 in CREPL. Whether maternal-fetal interface inflammation related to PM2.5 exposure during the periovulatory period or later contributes to CREPL or other adverse pregnancy outcomes requires further study.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Feminino , Gravidez , Material Particulado/toxicidade , Material Particulado/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Interleucina-6 , Fator de Necrose Tumoral alfa , Placenta/química , Exposição Materna/efeitos adversos , Inflamação/induzido quimicamente , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise
15.
Angew Chem Int Ed Engl ; 61(38): e202208960, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35861476

RESUMO

Thermochromic phosphors are intriguing materials for realizing thermochromic behaviors of light-emitting diodes. Here a highly luminescent and stable thermochromic phosphor based on one-dimensional Cu4 I6 (4-dimethylamino-1-ethylpyridinium)2 is reported. This unique ionic copper-iodine chain-based hybrid exhibits near-unity photoluminescence efficiency owing to the through-space charge-transfer character of relevant electronic transitions. More importantly, an alternative mechanism of thermochromic phosphorescence was unraveled, supported by a first principles simulation of concerted copper atom migration in the copper-iodine chain. Furthermore, we successfully fabricate a bright thermochromic light-emitting diode using this Cu4 I6 (4-dimethylamino-1-ethylpyridinium)2 thermochromic phosphor. Our reported flexible ionic copper-iodine chain-based thermochromic luminescent material represents a new type of cost-effective functional phosphor.

16.
J Am Chem Soc ; 144(18): 8162-8170, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35442667

RESUMO

All-inorganic CsPbI3 perovskite is attractive for deep-red light-emitting diodes (LEDs) because of its excellent carrier mobility, high color purity, and solution processability. However, the high phase transition energy barrier of optically active CsPbI3 black phase hinders the fabrication of efficient and bright LEDs. Here, we report a novel α-BaF2 nanoparticle substrate-promoted solution-processable heteroepitaxial growth to overcome this hindrance and obtain high-quality optically active γ-CsPbI3 thin films, achieving efficient and bright deep-red LEDs. We unravel that the highly exposed planes on the α-BaF2 nanoparticle-based heteroepitaxial growth substrate have a 99.5% lattice matching degree with the (110) planes of γ-CsPbI3. This ultrahigh lattice matching degree initiates solution-processed interfacial strain-free epitaxial growth of low-defect and highly oriented γ-CsPbI3 thin films on the substrate. The obtained γ-CsPbI3 thin films are uniform, smooth, and highly luminescent, based on which we fabricate efficient and bright deep-red LEDs with a high peak external quantum efficiency of 14.1% and a record luminance of 1325 cd m-2.

17.
Sci Total Environ ; 829: 154564, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35302014

RESUMO

The association between ambient fine particulate matter (PM2.5) and systemic inflammation in women with early pregnancy is unclear. This study estimated the effects of PM2.5 exposures on inflammatory biomarkers in women with normal early pregnancy (NEP) or clinically recognized early pregnancy loss (CREPL). Serum interleukin-1beta (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured in 228 early pregnant women recruited in Tianjin, China. Maternal PM2.5 exposures at lag 0 through lag 30 before blood collection were estimated using temporally-adjusted land use regression models. Daily exposures to ambient PM10, NO2, SO2, CO and 8-hours maximum ozone were estimated using city-level concentrations. Single-day lag effects at lag 0 through lag 7 were estimated using multivariable linear regression models. Distributed lag effects and cumulative effects over the preceding seven days and 30 days were estimated using distributed lag non-linear models. Serum IL-1ß (8.0% increase at lag 3), IL-6 (33.9% increase at lag 5) and TNF-α (12.7% increase at lag 5) in early pregnant women were significantly increased with an interquartile range increase in PM2.5 exposures adjusted for temporal confounders and demographic characteristics. These effects were robust in several two-pollutant models. Distributed lag effects over the preceding 30 days also showed that the three cytokines were significantly increased with PM2.5 on some lag days. Among all cumulative effects of PM2.5 on the three cytokines in all subjects or in the two groups, only IL-6 was significantly increased in CREPL women over the preceding seven days and 30 days. No significant cumulative effect of PM2.5 was observed in NEP women. In conclusion, exposure to ambient PM2.5 may induce systemic inflammation in women in the first trimester of pregnancy. Whether the PM2.5-related cumulative increase in maternal IL-6 is involved in the pathogenic mechanisms of early pregnancy loss needs to be identified in future research.


Assuntos
Aborto Espontâneo , Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Exposição Ambiental/análise , Feminino , Humanos , Inflamação , Interleucina-6 , Material Particulado/análise , Gravidez , Fator de Necrose Tumoral alfa
18.
J Am Chem Soc ; 143(47): 19928-19937, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34766754

RESUMO

Lead halide perovskite nanocrystals (PNCs) are emerging as promising light emitters to be actively explored for high color purity and efficient light-emitting diodes. However, the most reported lead halide perovskite nanocrystal light-emitting diodes (PNCLEDs) encountered issues of emission line width broadening and operation voltage elevating caused by the quantum confinement effect. Here, we report a new type of PNCLED using large-size CsPbBr3 PNCs overly exceeding the Bohr exciton diameter, achieving ultranarrow emission line width and rapid brightness rise around the turn-on voltage. We adopt calcium-tributylphosphine oxide hybrid ligand passivation to produce highly dispersed large-size colloidal CsPbBr3 PNCs with a weak size confinement effect and also high photoluminescence quantum yield (∼85%). Utilizing these large-size PNCs as emitters, we manifest that the detrimental effects caused by the quantum confinement effect can be avoided in the device, thereby realizing the highest color purity in green PNCLED, with a narrow full width at half-maximum of 16.4 nm and a high corrected maximum external quantum efficiency of 17.85%. Moreover, the operation half-life time of the large-size PNCLED is 5-fold of that based on smaller-size PNCs. Our work provides a new avenue for improving the performance of PNCLEDs based on unconventional large-size effects.

19.
Nano Lett ; 21(20): 8756-8763, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637318

RESUMO

Metal halide perovskites are promising semiconductors for next-generation light-emitting diodes (LEDs) due to their high luminance, excellent color purity, and handily tunable band gap. However, it remains a great challenge to develop perovskite LEDs (PeLEDs) with pure red emission at the wavelength of 630 nm. Herein, we report a spectrally stable and efficient pure red PeLED by employing sequential ligand post-treated CsPbI3 quantum dots (QDs). The synthesized CsPbI3 QDs with a size of ∼5 nm are treated in sequential steps using the ligands of 1-hydroxy-3-phenylpropan-2-aminium iodide (HPAI) and tributylsulfonium iodide (TBSI), respectively. The CsPbI3 QD films exhibit improved optoelectronic properties, which enables the fabrication of a pure red PeLED with a peak external quantum efficiency (EQE) of 6.4% and a stable EL emission centered at the wavelength of 630 nm. Our reported sequential ligand post-treatment strategy opens a new route to improve the stability and efficiency of PeLEDs based on QDs.

20.
J Am Chem Soc ; 143(29): 10860-10864, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34279083

RESUMO

Chiral chromophores and their ordered assemblies are intriguing for yielding circularly polarized luminescence (CPL) and exploring intrinsic structure-light emission relationships. With the extensively studied chiral organic molecules and inorganic nanoparticle assemblies for the amplified CPL, the assemblies of copper halide hybrid clusters have attracted intensive attention due to their potential efficient CPL. Here, we report robust chiral phosphine-copper iodide hybrid clusters and their layered assemblies in crystalline states for amplified CPL. We reveal that the intermolecular interactions endow the clusters with the capability of assembling into chiral crystalline CPL materials, including hexagonal platelet-shaped microcrystals (glum ≈ 9.5 × 10-3) and highly oriented crystalline films (glum ≈ 5 × 10-3). Owing to the high crystalline feature of the thin film, we demonstrate an electroluminescent device with bright electroluminescence (1200 cd m-2).

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