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CD4+ T cells with latent HIV-1 infection persist despite treatment with antiretroviral agents and represent the main barrier to a cure of HIV-1 infection. Pharmacological disruption of viral latency may expose HIV-1-infected cells to host immune activity, but the clinical efficacy of latency-reversing agents for reducing HIV-1 persistence remains to be proven. Here, we show in a randomized-controlled human clinical trial that the histone deacetylase inhibitor panobinostat, when administered in combination with pegylated interferon-α2a, induces a structural transformation of the HIV-1 reservoir cell pool, characterized by a disproportionate overrepresentation of HIV-1 proviruses integrated in ZNF genes and in chromatin regions with reduced H3K27ac marks, the molecular target sites for panobinostat. By contrast, proviruses near H3K27ac marks were actively selected against, likely due to increased susceptibility to panobinostat. These data suggest that latency-reversing treatment can increase the immunological vulnerability of HIV-1 reservoir cells and accelerate the selection of epigenetically privileged HIV-1 proviruses.
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Infecções por HIV , HIV-1 , Inibidores de Histona Desacetilases , Interferon-alfa , Panobinostat , Provírus , Humanos , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Panobinostat/uso terapêutico , Provírus/efeitos dos fármacos , Latência Viral , Inibidores de Histona Desacetilases/uso terapêutico , Interferon-alfa/uso terapêuticoRESUMO
HIV-1-infected cells that persist despite antiretroviral therapy (ART) are frequently considered "transcriptionally silent," but active viral gene expression may occur in some cells, challenging the concept of viral latency. Applying an assay for profiling the transcriptional activity and the chromosomal locations of individual proviruses, we describe a global genomic and epigenetic map of transcriptionally active and silent proviral species and evaluate their longitudinal evolution in persons receiving suppressive ART. Using genome-wide epigenetic reference data, we show that proviral transcriptional activity is associated with activating epigenetic chromatin features in linear proximity of integration sites and in their inter- and intrachromosomal contact regions. Transcriptionally active proviruses were actively selected against during prolonged ART; however, this pattern was violated by large clones of virally infected cells that may outcompete negative selection forces through elevated intrinsic proliferative activity. Our results suggest that transcriptionally active proviruses are dynamically evolving under selection pressure by host factors.
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HIV-1/genética , Provírus/genética , Transcrição Gênica , Idoso , Sequência de Bases , Evolução Biológica , Cromatina/metabolismo , Células Clonais , DNA Viral/genética , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Ionomicina/farmacologia , Masculino , Pessoa de Meia-Idade , Filogenia , Provírus/efeitos dos fármacos , RNA Viral/genética , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos , Integração Viral/genética , Latência Viral/efeitos dos fármacos , Latência Viral/genéticaRESUMO
Humoral responses in coronavirus disease 2019 (COVID-19) are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined post mortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers and a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+ TFH cell differentiation together with an increase in T-bet+ TH1 cells and aberrant extra-follicular TNF-α accumulation. Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+ TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections, and suggest that achieving herd immunity through natural infection may be difficult.
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Infecções por Coronavirus/imunologia , Centro Germinativo/imunologia , Pneumonia Viral/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/imunologia , COVID-19 , Feminino , Centro Germinativo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Baço/imunologia , Baço/patologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Human immunodeficiency virus 1 (HIV-1) reservoir cells persist lifelong despite antiretroviral treatment1,2 but may be vulnerable to host immune responses that could be exploited in strategies to cure HIV-1. Here we used a single-cell, next-generation sequencing approach for the direct ex vivo phenotypic profiling of individual HIV-1-infected memory CD4+ T cells from peripheral blood and lymph nodes of people living with HIV-1 and receiving antiretroviral treatment for approximately 10 years. We demonstrate that in peripheral blood, cells harbouring genome-intact proviruses and large clones of virally infected cells frequently express ensemble signatures of surface markers conferring increased resistance to immune-mediated killing by cytotoxic T and natural killer cells, paired with elevated levels of expression of immune checkpoint markers likely to limit proviral gene transcription; this phenotypic profile might reduce HIV-1 reservoir cell exposure to and killing by cellular host immune responses. Viral reservoir cells harbouring intact HIV-1 from lymph nodes exhibited a phenotypic signature primarily characterized by upregulation of surface markers promoting cell survival, including CD44, CD28, CD127 and the IL-21 receptor. Together, these results suggest compartmentalized phenotypic signatures of immune selection in HIV-1 reservoir cells, implying that only small subsets of infected cells with optimal adaptation to their anatomical immune microenvironment are able to survive during long-term antiretroviral treatment. The identification of phenotypic markers distinguishing viral reservoir cells may inform future approaches for strategies to cure and eradicate HIV-1.
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Linfócitos T CD4-Positivos , Infecções por HIV , HIV-1 , Fenótipo , Latência Viral , Humanos , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/imunologia , HIV-1/isolamento & purificação , Provírus/efeitos dos fármacos , Provírus/genética , Provírus/isolamento & purificação , Carga Viral , Latência Viral/efeitos dos fármacos , Memória Imunológica , Linfonodos/citologia , Linfonodos/imunologia , Sobrevivência Celular , Antígenos CD28 , Receptores de Interleucina-21RESUMO
The development of many quantum optical technologies depends on the availability of single quantum emitters with near-perfect coherence. Systematic improvement is limited by a lack of understanding of the microscopic energy flow at the single-emitter level and ultrafast timescales. Here we utilize a combination of fluorescence correlation spectroscopy and ultrafast spectroscopy to capture the sample-averaged dynamics of defects with single-particle sensitivity. We employ this approach to study heterogeneous emitters in two-dimensional hexagonal boron nitride. From milliseconds to nanoseconds, the translational, shelving, rotational and antibunching features are disentangled in time, which quantifies the normalized two-photon emission quantum yield. Leveraging the femtosecond resolution of this technique, we visualize electron-phonon coupling and discover the acceleration of polaronic formation on multi-electron excitation. Corroborated with theory, this translates to the photon fidelity characterization of cascaded emission efficiency and decoherence time. Our work provides a framework for ultrafast spectroscopy in heterogeneous emitters, opening new avenues of extreme-scale characterization for quantum applications.
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Breast cancer susceptibility 1/2 (BRCA1/2) genes play a crucial role in DNA damage repair, yet mutations in these genes increase the susceptibility to tumorigenesis. Exploiting the synthetic lethality mechanism between BRCA1/2 mutations and poly(ADP-ribose) polymerase (PARP) inhibition has led to the development and clinical approval of PARP inhibitor (PARPi), representing a milestone in targeted therapy for BRCA1/2 mutant tumors. This approach has paved the way for leveraging synthetic lethality in tumor treatment strategies. Despite the initial success of PARPis, resistance to these agents diminishes their efficacy in BRCA1/2-mutant tumors. Investigations into PARPi resistance have identified replication fork stability and homologous recombination repair as key factors sensitive to PARPis. Additionally, studies suggest that replication gaps may also confer sensitivity to PARPis. Moreover, emerging evidence indicates a correlation between PARPi resistance and cisplatin resistance, suggesting a potential overlap in the mechanisms underlying resistance to both agents. Given these findings, it is imperative to explore the interplay between replication gaps and PARPi resistance, particularly in the context of platinum resistance. Understanding the impact of replication gaps on PARPi resistance may offer insights into novel therapeutic strategies to overcome resistance mechanisms and enhance the efficacy of targeted therapies in BRCA1/2-mutant tumors.
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Proteína BRCA1 , Proteína BRCA2 , Resistencia a Medicamentos Antineoplásicos , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína BRCA2/genética , Proteína BRCA1/genética , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Neoplasias/genética , Neoplasias/tratamento farmacológicoRESUMO
Formamidinium lead iodide (FAPbI3) perovskite has lately surfaced as the preferred contender for highly proficient and robust perovskite solar cells (PSCs), owing to its favorable bandgap and superior thermal stability. Nevertheless, volatilization and migration of iodide ions (I-) result in non-radiating recombination centers, and the presence of large formamidine (FA) cations tends to cause lattice strain, thereby reducing the power conversion efficiency (PCE) and stability of PSCs. To solve these problems, the lead formate (PbFa) is added into the perovskite solution, which effectively mitigates the halogen vacancy and provides tensile strain outside the perovskite lattice, thereby enhancing its properties. The strong coordination between the CâO of HCOO- and Pb-I backbones effectively immobilizes anions, significantly increases the energy barrier for anion vacancy formation and migration, and reduces the risk of lead ion (Pb2+) leakage, thereby improving the operation and environmental safety of the device. Consequently, the champion PCE of devices with Ag electrodes can be increased from 22.15% to 24.32%. The unencapsulated PSCs can still maintain 90% of the original PCE even be stored in an N2 atmosphere for 1440 h. Moreover, the target devices have significantly improved performance in terms of light exposure, heat, or humidity.
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High voltage cobalt-free spinel LiNi0.5Mn1.5O4 (LNMO) is well organized as a high-power cathode material for lithium (Li)-ion batteries, however, the weak interaction between the 3d orbital of the transition metal (TM) ions and the 2p orbital of oxygen (O) leads to the instability of crystal structural, hindering the long-term stable cycling of LNMO cathode especially at high temperatures. Here, a design strategy of orbital interaction is initiated to strengthen TM 3d-O 2p framework in P-doped LNMO (P-LNMO) by choosing phytic acid as P dopant, which can realize more uniform doping compared to regular phosphate. The results show that the enhancement of TM 3d-O 2p orbital interaction in P-LNMO can suppress the Jahn-Teller effect and subsequent dissolution of Mn, as well as lowers the energy barrier for Li ion insertion/extraction kinetics. As a result, superior electrochemical performances including high discharge capacity, stable cycling behavior and enhanced rate capability of P-LNMO are obtained. Significantly, the P-LNMO pouch cell shows great cycling stability with 97.4% capacity retention after 100 cycles.
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Solar-driven interfacial evaporation (SDIE) is a highly promising approach to achieve sustainable desalination and tackle the global freshwater crisis. Despite advancements in this field, achieving balanced thermal localization and salt resistance remains a challenge. Herein, the study presents a 3D hierarchical porous ceramic platform for SDIE applications. The utilized alumina foam ceramics (AFCs) exhibit remarkable corrosion resistance and chemical stability, ensuring a prolonged operational lifespan in seawater or brines. The millimeter-scale air-filled pores in AFCs prevent thermal losses through conduction with bulk water, resulting in heat-localized interfaces. The hydrophilic nature of macroporous AFC skeletons facilitates rapid water replenishment on the evaporating surface for effective salt-resistant desalination. Benefiting from its self-radiation adsorption and side-assisted evaporation capabilities, the AFC-based evaporators exhibit high indoor evaporation rates of 2.99 and 3.54 kg m-2 h-1 under one-sided and three-sided illumination under 1.0 sun, respectively. The AFC-based evaporator maintains a high evaporation rate of ≈2.77 kg m-2 h-1 throughout the 21-day long-term test. Furthermore, it achieves a daily water productivity of ≈10.44 kg m-2 in outdoor operations. This work demonstrates the potential of 3D hierarchical porous ceramics in addressing the trade-off between heat localization and salt resistance, and contributes to the development of durable solar steam generators.
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Bone marrow mesenchymal stem cells (BMSCs) are indispensable cells constituting the bone marrow microenvironment that are generally recognized as being involved in the development and progression of osteosarcoma (OS). To explore whether mTORC2 signaling inhibition in BMSCs suppressed OS growth and tumor-caused bone destruction, 3-month-old littermates genotyped Rictorflox/flox or Prx1-cre; Rictorflox/flox (with same gender) were injected with K7M2 cells in the proximal tibia. After 40 days, bone destruction was alleviated in Prx1-cre; Rictorflox/flox mice, as observed on X-ray and micro-CT. This was accompanied by decreased serum N-terminal propeptide of procollagen type I (PINP) levels and reduced tumor bone formation in vivo. Interactions between K7M2 and BMSCs were studied in vitro. Rictor-deficient BMSCs, which were cultured in tumor-conditioned medium (TCM), caused reduced bone proliferation and suppressed osteogenic differentiation. Moreover, compared with the control group, K7M2 cells cultured in BCM (culture medium extracted from Rictor-deficient BMSCs) displayed less proliferation, migration, and invasion, and attenuated osteogenic activity. Forty types of cytokines were then analyzed by mouse cytokine array and decreased levels CCL2/3/5 and interleukin-16 were detected in Rictor-deficient BMSCs. These results suggested that inhibition of mTORC2 (Rictor) signaling pathway in BMSCs exerted anti-OS effects through 2 mechanisms: (1) by suppressing the proliferation and osteogenic differentiation of BMSCs induced by OS to alleviate bone destruction; (2) by reducing the secretion of cytokines by BMSCs, which are closely related to OS cell growth, migration, invasion, and tumorigenic osteogenesis.
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Neoplasias Ósseas , Células-Tronco Mesenquimais , Osteossarcoma , Camundongos , Animais , Osteogênese , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular , Células da Medula Óssea , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Citocinas/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Células Cultivadas , Osteossarcoma/metabolismo , Microambiente TumoralRESUMO
Two-dimensional (2D) MBenes have enormous potential in energy applications. Vanadium metal, with its versatile and tunable electronic states, can further enhance the electrochemical performance of MBenes. However, most MBenes are composed of a few atomic layers as the metal boron (MB) block, e.g., M2B2, which might lead to instability and poor mechanical response. Herein, we designed and predicted 2D V4B6 associated with different terminations (T = Cl, O, S) using a top-down method and global search for parental V4AB6. Among the A element candidates, the P-glued MAB phase exhibited high stability and easy synthesizability. Moreover, 2D V4B6 was feasibly formed and easily exfoliated owing to its weak V-P bonding. Most of the surface functionalization could improve both the mechanical and electrochemical properties of the V4B6 monolayer. In particular, 2D V4B6S2 exhibited a high potential as an anode material for lithium-ion batteries (LIBs) with high theoretical capacity (297 mA h g-1), low diffusion barrier (0.166 eV), and low open circuit voltage (0.136 V), outperforming a majority of MXenes and transition metal sulfide layers. This work offers a new strategy for designing desirable 2D layers from parental materials, and tuning their properties via composition and surface functionalization, which could shed light on the development of other 2D metal-ion anodes.
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In Dermanyssus gallinae, a hematophagous mite, the initiation of vitellogenesis induced by blood feeding is essential for its reproduction. However, the precise gene structures and physiological functions of Vg in D. gallinae and its upstream gene, Target of Rapamycin (TOR), have not been fully understood. This study revealed the presence of four homologous genes within D. gallinae, named Dg-Vg1, Dg-Vg1-like, Dg-Vg2, and Dg-Vg2-like, especially, Dg-Vg2-like was firstly identified in the mites. The expression levels of all these Vg genes were significantly higher in adult females than other stages. Following blood feeding, the expression levels of these genes increased significantly, followed by a subsequent decrease, aligning with egg production. Silencing Dg-Vgs by RNA interference (RNAi) led to decreased fecundity and egg hatching rates, as well as abnormal embryonic development, suggesting a vital role for Dg-Vgs in both egg formation and embryonic development. Furthermore, the knockdown of Dg-TOR significantly reduced the expression of Dg-Vgs and negatively impacted the reproductive capabilities of PRMs, indicating that TOR influences PRM reproduction by regulating the expression of Dg-Vgs. In summary, these findings demonstrated the crucial roles of Dg-Vgs and Dg-TOR in PRM reproduction, highlighting their potential as targets for pest control.
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Ácaros , Interferência de RNA , Reprodução , Serina-Treonina Quinases TOR , Vitelogeninas , Animais , Vitelogeninas/genética , Vitelogeninas/metabolismo , Feminino , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Ácaros/genética , Ácaros/fisiologia , Masculino , Sequência de Aminoácidos , Filogenia , Fertilidade/genética , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Vitelogênese/genéticaRESUMO
Dermanyssus gallinae, a worldwide pest in birds, has developed varying degrees of resistance to insecticides. The ATP-binding cassette (ABC) transporters are essential for the removal of xenobiotics from arthropods. However, our knowledge about ABC transporter proteins in D. gallinae is limited. Forty ABC transporters were identified in the transcriptome and genome of D. gallinae. The resistant population displayed an augmented metabolic rate for beta-cypermethrin compared to the susceptible group, with a remarkable increase in the content of ABC transporters. Verapamil was found able to increase the toxicity of beta-cypermethrin in the resistant population. Results from qRT-PCR analysis showed that eleven ABC transcripts were more highly expressed in the resistant population than the susceptible group at all stages of development, and beta-cypermethrin was observed to be able to induce the expression of DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 in D. gallinae. RNAi-mediated knockdown of the five genes was observed to increase the susceptibility of resistant mites to beta-cypermethrin. These results suggest that ABC transporters, DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 genes, may be related to beta-cypermethrin resistance in D. gallinae. This research will serve as a foundation for further studies on mechanism of insecticide resistance, which could be beneficial for controlling D. gallinae.
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Transportadores de Cassetes de Ligação de ATP , Ácaros , Piretrinas , Animais , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Piretrinas/farmacologia , Piretrinas/toxicidade , Ácaros/efeitos dos fármacos , Ácaros/genética , Inseticidas/farmacologia , Inseticidas/toxicidade , Aves Domésticas , Resistência a Inseticidas/genéticaRESUMO
OBJECTIVE: This study aims to investigate and analyze the risk factors of convulsions in children with rotavirus gastroenteritis and to construct a nomogram prediction model. METHODS: A retrospective analysis was performed on 940 cases of pediatric patients with rotavirus gastroenteritis treated in our hospital from December 2017 to December 2022. Based on whether convulsions occurred during hospitalization, patients were divided into the convulsion group (n = 135) and the convulsion-free group (n = 805). Clinical information of patients in both groups was collected, logistic regression analysis was carried out to analyze the convulsion risk factors pertaining to children with rotavirus gastroenteritis, and a nomogram prediction model was constructed. RESULTS: The univariate analysis revealed that fever, frequency of diarrhea, white blood cell count, blood calcium level, blood glucose level, CO 2 CP, creatine kinase myocardial band (CK-MB), and blood pH value were all factors that display statistically significant differences at the level of P = 0.05. Then, logistic regression analysis was carried out, taking the occurrence of such convulsions as the dependent variable and the aforementioned factors as independent variables. The results show that fever, frequency of diarrhea, blood calcium, CO 2 CP, and CK-MB were the independent risk factors ( P < 0.05), whereas the area under the receiver operating characteristic curve (area under the curve) of the constructed nomogram prediction model based on these factors was 0.842 (95% confidence interval, 0.821-0.914). CONCLUSIONS: Frequency of diarrhea, blood calcium, CO 2 CP, and CK-MB are independent risk factors for the occurrence of convulsions in children with rotavirus gastroenteritis. The nomogram prediction model constructed based on these risk factors provides guidance and value in effectively preventing and controlling convulsions in children with rotavirus gastroenteritis.
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Gastroenterite , Nomogramas , Infecções por Rotavirus , Convulsões , Humanos , Estudos Retrospectivos , Masculino , Fatores de Risco , Feminino , Infecções por Rotavirus/complicações , Infecções por Rotavirus/epidemiologia , Convulsões/epidemiologia , Convulsões/etiologia , Gastroenterite/virologia , Gastroenterite/epidemiologia , Gastroenterite/complicações , Pré-Escolar , Lactente , Modelos Logísticos , Curva ROC , Criança , RotavirusRESUMO
Cesium lead halide perovskite nanocrystals (PNCs) have emerged as a potential next-generation single quantum emitter (QE) material for quantum optics and quantum information science. Optical dephasing processes at cryogenic temperatures are critical to the quality of a QE, making a mechanistic understanding of coherence losses of fundamental interest. We use photon-correlation Fourier spectroscopy (PCFS) to obtain a lower bound to the optical coherence times of single PNCs as a function of temperature. We find that 20 nm CsPbBr3 PNCs emit nearly exclusively into a narrow zero-phonon line from 4 to 13 K. Remarkably, no spectral diffusion is observed at time scales of 10 µs to 5 ms. Our results suggest that exciton dephasing in this temperature range is dominated by elastic scattering from phonon modes with characteristic frequencies of 1-3 meV, while inelastic scattering is minimal due to weak exciton-phonon coupling.
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Lead halide perovskite nanocrystals (LHP NCs) are an emerging materials system with broad potential applications, including as emitters of quantum light. We apply design principles aimed at the structural optimization of surface ligand species for CsPbBr3 NCs, leading us to the study of LHP NCs with dicationic quaternary ammonium bromide ligands. Through the selection of linking groups and aliphatic backbones guided by experiments and computational support, we demonstrate consistently narrow photoluminescence line shapes with a full-width-at-half-maximum below 70 meV. We observe bulk-like Stokes shifts throughout our range of particle sizes, from 7 to 16 nm. At cryogenic temperatures, we find sub-200 ps lifetimes, significant photon coherence, and the fraction of photons emitted into the coherent channel increasing markedly to 86%. A 4-fold reduction in inhomogeneous broadening from previous work paves the way for the integration of LHP NC emitters into nanophotonic architectures to enable advanced quantum optical investigation.
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Green organic materials composed of C, H, O, and N elements are receiving more and more attention worldwide. However, the high solubility, poor electrical conductivity, and long activation time limit the development of organic materials in practice. Herein, two stable covalent organic materials with alkynyl linkage between benzene rings and benzothiadiazole groups with different amounts of fluorine atoms modification (defined as BOP-0F and BOP-2F), are designed for lithium-ion batteries. Both BOP-0F and BOP-2F can achieve superior reversible capacities of ≈719.8 and 713.5â mAh g-1 over 100â cycles on account of the redox activity of alkynyl (two-electron involved) and benzothiadiazole units (five-electron involved) in these organic materials. While BOP-2F electrodes exhibit much more stable cycling performance than BOP-0F electrodes, especially without pronounced capacity ascending during initial cycling. It can be assigned to the synergy effect of alkynyl linkage and fluorine atom modification in BOP-2F. The lithium storage and activation mechanism of alkynyl, benzothiadiazole, and fluorine groups have also been deeply probed by a series of material characterizations and theoretical simulations. This work could be noteworthy in providing novel tactics for the molecular design and investigation of high-efficiency organic electrodes for energy storage.
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Fatal issues in lithium metal anodes (LMA), such as detrimental lithium dendrites growth and fragile solid-electrolyte interphase (SEI) during the Li plating/stripping process, often hinder the practical application of Li metal batteries (LMBs). Herein, cobalt-coordinated sp-carbon-conjugated organic polymer (Co-spc-COP) is constructed as the protective layer for regulating the interface stability of LMA. The unique synergistic beneficial effect of organic functional groups (C≡C linkage, C=N units and aromatic rings) and Co sites not only regulate the Li+ coordination environment and rearrange Li+ concentration to facilitate its transport by optimizing the electronic density, enhancing the compatibility with electrolyte interface and supplying "external magnetic driving strategy", but also strengthens the interfacial stiffness with high Young's modulus to better withstand the mechanical stress. These beneficial effects and relative underlying working mode and mechanism of uniform Li plating and rapid Li+ migration on the Co-spc-COP are also revealed by various in situ/ex situ experimental technologies and theory calculation. The Co-spc-COP-based cell delivers an extraordinary lifespan of 6600â h and ultrahigh capacity retention of 78.3 % (111.9â mAh g-1) after 1000â cycles at 1â C. This demonstrated synergistic strategy in Co-coordinated organic polymer may gain new insights to regulate the uniform and non-dendritic deposition/dissolution behaviors for highly stable LMBs.
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The appearance of disordered lithium dendrites and fragile solid electrolyte interfaces (SEI) significantly hinder the serviceability of lithium metal batteries. Herein, guided by theoretical predictions, a multi-component covalent triazine framework with partially electronegative channels (4C-TA0.5TF0.5-CTF) is incorporated as a protective layer to modulate the interface stability of the lithium metal batteries. Notably, the 4C-TA0.5TF0.5-CTF with optimized electronic structure at the molecular level by fine-tuning the local acceptor-donor functionalities not only enhances the intermolecular interaction thereby providing larger dipole moment and improved crystallinity and mechanical stress, but also facilitates the beneficial effect of lithiophilic sites (C-F bonds, triazine cores, C=N linkages and aromatic rings) to further regulate the migration of Li+ and achieve a uniform lithium deposition behavior as determined by various in-depth in/ex situ characterizations. Due to the synergistic effect of multi-component organic functionalities, the 4C-TA0.5TF0.5-CTF modified full cells perform significantly better than the common two/three-component 2C-TA-CTF and 3C-TF-CTF electrodes, delivering an excellent capacity of 116.3 mAh g-1 (capacity retention ratio: 86.8%) after 1000 cycles at 5 C and improved rate capability. This work lays a platform for the prospective molecular design of improved organic framework relative artificial SEI for highly stable lithium metal batteries.
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INTRODUCTION: This study aimed to investigate the possible role of galectin-3 in epilepsy and further explore its underlying mechanisms. METHODS: Sprague-Dawley rats were intraperitoneally injected with 30 mg/kg pilocarpine to induce an animal model of epilepsy. To inhibit galectin-3, the epilepsy model of rats was intraperitoneally injected with TD139. The severity of the seizure was graded according to the Racine score. The pathological changes in hippocampal CA1 regions were observed by hematoxylin and eosin and Nissl staining. Enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, and Western blot were used to detect the levels of cytokines and pyroptosis-related factors. The in vitro effects of galectin-3 were confirmed on BV2 cells and rat primary microglia by transfection with lentivirus vectors carrying Lgals3 shRNA or by treatment with TD139. RESULTS: A higher expression of galectin-3 was observed in the hippocampal CA1 regions of epilepsy rats than in sham rats. Inhibition of galectin-3 by administration of TD139 improved the severity of the seizure, hippocampal damage, and neuron loss. TD139 administration suppressed the expression of NLRP3, ASC, c-caspase-1, and GSDMD-N, and reduced the levels of cytokines. In kainic acid-treated microglia, Lgals3 shRNA or TD139 significantly inhibited Iba1 expression and limited NLRP3/pyroptosis-triggered inflammation. CONCLUSION: Galectin-3 activates the NLRP3/pyroptosis signaling pathway to promote microglial activation and neuroinflammation during epilepsy disease progression.