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1.
ACS Appl Mater Interfaces ; 16(38): 50887-50896, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39262274

RESUMO

In the quest for sustainable and renewable energy sources, researchers and engineers have explored innovative technologies to harvest energy from various environmental sources. Dielectric elastomer generators (DEGs) with high energy harvesting performance have been proven to be promising energy collectors, but achieving a high dielectric constant (ε') and low electrical conductivity (EC) under high electric fields of dielectric elastomer (DE) simultaneously is a struggle, which poses significant challenges. In this study, high-content carboxyl group-grafted liquid polybutadiene (HCPB) is synthesized and then adopted as an organic dielectric filler to blend and cocross-link with a butadiene rubber (BR) matrix to prepare DE composites with high energy harvesting performance. The introduction of carboxyl groups enhances polarization while trapping free Al3+ in the matrix, which revolutionarily achieves a significant increase in ε' under extremely low EC. Ultimately, the contradiction between increased ε' and decreased EC under high electric fields is reconciled, resulting in a 30 HCPB/BR composite with high energy density (w = 91.9 mJ/cm3) and fine power conversion efficiency (PCE = 24.1%). This advancement paves the way for the development of HCPB/BR composite-based DEGs with enhanced ε' and energy harvesting performance.

2.
J Gen Psychol ; : 1-29, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39340430

RESUMO

Making judgments of learning (JOLs) can directly influence memory, a phenomenon termed the reactivity effect of JOLs. However, controversy surrounds the mechanism behind JOL reactivity. This study employs related and unrelated word pairs as learning materials to compare memory outcomes across different JOL conditions. We contrasted the traditional JOL reactivity paradigm with a covert retrieval induction paradigm to explore whether JOLs impact memory through covert retrieval. In Experiment 1, data from 40 participants (18 females, 22 males) were analyzed, revealed distinct patterns between the two paradigms. When word pairs are presented entirely, the JOL group outperforms the no-JOL group in memorizing related pairs, aligning with traditional JOL reactivity. Conversely, when target words are omitted, the JOL group's memory resembles that of the no-JOL group. This comparison suggested that JOLs may prompt covert retrieval. In Experiment 2, which involved manipulating the retrieval strength, data from 52 participants (46 females, 6 males) were analyzed, yielded results consistent with those of Experiment 1. We conclude that covert retrieval significantly contributes to the JOL reactivity effect, enhancing memory through JOL-induced covert retrieval.

4.
Int Microbiol ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129035

RESUMO

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts that engage in crucial interactions with plants, playing a vital role in grassland ecology. Our study focuses on the pioneer plant Agropyron cristatum, and we collected soil samples from four degraded grasslands in Yudaokou to investigate the response of community composition to the succession of degraded grasslands. We measured the vegetation status, soil physical and chemical properties, AMF colonization, and spore density in different degraded grasslands. High-throughput sequencing was employed to analyze AMF in soil samples. Correlations among community composition, soil characteristics, and plant factors were studied using principal component and regression analyses. The distribution of AMF in grasslands exhibited variation with different degrees of degradation, with Glomus, Scutellospora, and Diversispora being the dominant genera. The abundance of dominant genera in AMF also varied, showing a gradual increase in the relative abundance of the genus Diversispora with higher degradation levels. AMF diversity decreased from 27.7% to 12.4% throughout the degradation process. Among 180 samples of Agropyron cristatum plants, AMF hyphae and vesicles displayed the highest infection status in non-degraded grasslands and the lowest in severely degraded ones. Peak AMF spore production occurred in August, with maximum values in the 0-10-cm soil layer, and the highest spore densities were found in lightly degraded grasslands. Apart from pH, soil factors exhibited a positive correlation with AMF infection during grassland degradation. Furthermore, changes in AMF community composition were jointly driven by vegetation and soil characteristics, with vegetation coverage and soil organic carbon significantly impacting AMF distribution. Significant differences in AMF variables (spore number and diversity index) were also observed at different soil depths. Grassland successional degradation significantly influences AMF community structure and composition. Our future focus will be on understanding response mechanisms and implementing improvement methods for AMF during grassland degradation and subsequent restoration efforts.

5.
Int J Biol Macromol ; 278(Pt 4): 135072, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39191341

RESUMO

Cancer, caused by uncontrolled proliferation of abnormal cells, has long been a global public health issue. For decades, natural products have been proven to be an essential source for novel anticancer drug discovery. But their instability, low solubility and bioavailability, poor targeting impede therapeutic efficacy. With the development of nanotechnology, nanomedicine delivery systems have emerged as promising strategies to improve bioavailability and enhance the therapeutic efficacy of drugs. However, constructing suitable nanocarrier is still a major challenge. Polysaccharides are extensively employed as carrier materials in nanomedicine delivery systems, owing to their unique physicochemical properties, biocompatibility and low immunogenicity. Polysaccharide-based nanomedicine delivery systems show high drug delivery efficiency, controlled drug release, and precise tumor targeting. This paper reviews influencing factors in the construction of polysaccharide-based nanocarriers and the application of polysaccharide-based nanocarriers for the delivery of natural products in treating various cancers. It focuses on their in vitro and in vivo anticancer efficacy and mechanisms. Furthermore, the review contrasts the capabilities and limitations of polysaccharide-based nanocarriers with traditional delivery methods, underlining their potential to enable targeted, reduced toxicity and excellent cancer treatment modalities. Finally, we discuss the current research limitations and future prospects in this emerging field.


Assuntos
Antineoplásicos , Produtos Biológicos , Portadores de Fármacos , Neoplasias , Polissacarídeos , Humanos , Polissacarídeos/química , Neoplasias/tratamento farmacológico , Portadores de Fármacos/química , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Nanomedicina/métodos
6.
ACS Appl Mater Interfaces ; 16(26): 33169-33181, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38915234

RESUMO

Inducing immunogenic cell death (ICD) is a promising strategy for cancer immunotherapy. Shikonin (SHK), a naphthoquinone compound from Lithospermum erythrorhizon, can stimulate antitumor immunity by inducing ICD. Nevertheless, the immunogenicity of tumor cells killed by SHK is weak. Endoplasmic reticulum (ER) stress is an important intracellular pathway of the ICD effect. Curcumin (CUR) can directly induce ER stress by disrupting Ca2+ homeostasis, which might enhance SHK-induced ICD effect. A self-delivery ICD effect nanobooster (CS-PEG NPs) was developed by the self-assembly of SHK (ICD inducer) and CUR (ICD enhancer) with the assistance of DSPE-PEG2K for cancer chemoimmunotherapy. CS-PEG NPs possessed effective CT26 tumor cell cellular uptake and tumor accumulation ability. Moreover, enhanced cytotoxicity against tumor cells and apoptosis promotion were achieved due to the synergistic effect of CUR and SHK. Notably, CS-PEG NPs induced obvious Ca2+ homeostasis disruption, ER stress, and ICD effect. Subsequently, the neoantigens produced by the robust ICD effect in vivo promoted dendritic cell maturation, which further recruited and activated cytotoxic T lymphocytes. Superior antitumor efficacy and systemic antitumor immunity were observed in the CT26-bearing BALB/c mouse model without side effects in major organs. This study offers a promising self-delivery nanobooster to induce strong ICD effect and antitumor immunity for cancer chemoimmunotherapy.


Assuntos
Curcumina , Estresse do Retículo Endoplasmático , Morte Celular Imunogênica , Imunoterapia , Camundongos Endogâmicos BALB C , Naftoquinonas , Animais , Naftoquinonas/química , Naftoquinonas/farmacologia , Morte Celular Imunogênica/efeitos dos fármacos , Camundongos , Curcumina/química , Curcumina/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Linhagem Celular Tumoral , Nanopartículas/química , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias/patologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Feminino
7.
Opt Lett ; 49(9): 2305-2308, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691705

RESUMO

Symbol-level fiber-longitudinal power profile estimation (PPE) greatly reduces the implementation complexity compared with the waveform-level PPE using oversampled data. However, symbol-rate data cannot account for the inter-sample interaction, which leads to inaccuracy of the absolute power estimation. To realize an accurate symbol-level PPE, we provide an in-depth analysis of the differences between symbol-level and waveform-level perturbation matrices and propose a power calibration method based on the trace of the inverse matrix. Evaluated in the probabilistic constellation shaping (PCS) 64QAM 130 Gbaud 5 × 50 km optical links, the root mean squared error (RMSE) of the symbol-level PPE decreases by 0.98 and 0.62 dB at erbium-doped fiber amplifier (EDFA) positions and all estimated positions with the aid of matrix calibration.

8.
Sci Rep ; 14(1): 11380, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762635

RESUMO

Metacognitive systematic bias impairs human learning efficiency, which is characterized by the inconsistency between predicted and actual memory performance. However, the underlying mechanism of metacognitive systematic bias remains unclear in existing studies. In this study, we utilized judgments of learning task in human participants to compare the neural mechanism difference in metacognitive systematic bias. Participants encoded words in fMRI sessions that would be tested later. Immediately after encoding each item, participants predicted how likely they would remember it. Multivariate analyses on fMRI data demonstrated that working memory and uncertainty decisions are represented in patterns of neural activity in metacognitive systematic bias. The available information participants used led to overestimated bias and underestimated bias. Effective connectivity analyses further indicate that information about the metacognitive systematic bias is represented in the dorsolateral prefrontal cortex and inferior parietal cortex. Different neural patterns were found underlying overestimated bias and underestimated bias. Specifically, connectivity regions with the dorsolateral prefrontal cortex, anterior cingulate cortex, and supramarginal gyrus form overestimated bias, while less regional connectivity forms underestimated bias. These findings provide a mechanistic account for the construction of metacognitive systematic bias.


Assuntos
Córtex Pré-Frontal Dorsolateral , Imageamento por Ressonância Magnética , Metacognição , Lobo Parietal , Humanos , Lobo Parietal/fisiologia , Lobo Parietal/diagnóstico por imagem , Masculino , Córtex Pré-Frontal Dorsolateral/fisiologia , Córtex Pré-Frontal Dorsolateral/diagnóstico por imagem , Feminino , Metacognição/fisiologia , Adulto Jovem , Adulto , Mapeamento Encefálico , Memória de Curto Prazo/fisiologia , Aprendizagem/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Julgamento/fisiologia
9.
Int Wound J ; 21(4): e14856, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531532

RESUMO

The aim of this research is to explore the therapeutic efficacy of platelet-rich plasma (PRP) on the cutaneous ulceration of diabetes mellitus (DM). From the beginning of the database until January 2024, we looked through several databases to obtain randomised, controlled PRP studies to treat the wound healing of DM in adult patients. The Cochrane Collaboration's Risk-Of-Bias Instrument was used to evaluate the risk of bias in randomised, controlled studies. Funnel plots, sensitivity analyses and Egger regression tests were employed to determine the reliability and effectiveness of the meta-analyses. Depending on the degree of heterogeneity, a fixed or random effect model has been used. The statistical significance was determined to be below 0.05. Altogether 281 trials were collected from the database and entered into Endnote Software for screening, and 15 trials were analysed. It was found that PRP was associated with a higher rate of wound healing (OR, 3.23; 95% CI, 2.42, 4.31 p < 0.0001). PRP was associated with a reduction in the risk of post-operative wound infection (OR, 0.46; 95% CI, 0.21, 0.99 p = 0.05). PRP was associated with a reduction in the risk of amputations amongst those with DM (OR, 0.50; 95% CI, 0.30, 0.84 p = 0.009). Overall, PRP treatment for DM is expected to improve the rate of wound healing, decrease the risk of wound infection and decrease the risk of amputations.


Assuntos
Diabetes Mellitus , Pé Diabético , Plasma Rico em Plaquetas , Úlcera Cutânea , Infecção dos Ferimentos , Adulto , Humanos , Reprodutibilidade dos Testes , Cicatrização , Extremidade Inferior , Pé Diabético/terapia
10.
ACS Appl Mater Interfaces ; 16(9): 11595-11604, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381554

RESUMO

Dielectric elastomer generator (DEG), which consists of a dielectric elastomer (DE) film sandwiched between two flexible electrodes (FEs), has the advantages of lightweight, high energy density, and high energy conversion efficiency, providing a simple and feasible solution for harvesting energy from human motion or nature. As crucial constituents of DEG, FEs are expected to possess excellent conductivity and compliance. Nevertheless, there is currently no quantitative characterization method for FE compliance. In addition, the impact mechanism of FE compliance on the energy harvesting performance and fatigue life of the DEG remains unclear. In this study, the dynamic mechanical property (DMP) was used to assess the compliance of FEs, and the quantitative characterization method of FE compliance was proposed. A series of silicone rubber electrodes (SREs) with different DMPs and compliance were designed and prepared, and the impact mechanism of FE compliance on the energy harvesting stability and fatigue life of the DEG was investigated. The results indicate that the key to achieving excellent FE compliance lies in reducing the difference in the magnitude of the complex modulus and phase angle between the FEs and DE, which can significantly reduce interfacial friction and extend the fatigue life of DEG. Benefiting from the enhanced FE compliance, the fatigue life and full-life energy density of the DEG device increase by 20.3 times and 26.4 times, respectively, compared with those of the commonly used carbon-based electrodes.

11.
Memory ; 32(3): 308-319, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335303

RESUMO

The recognition of associative memory can be significantly influenced by the use of an encoding strategy known as unitisation, which has been implemented through various manipulations. However, [Shao, H., Opitz, B., Yang, J., & Weng, X. (2016). Recollection reduces unitised familiarity effect. Memory (Hove, England), 24(4), 535-547. https://doi.org/10.1080/09658211.2015.1021258] found intriguing distinctions between two common manipulations, the compound task and the imagery task, leading to a dispute. We propose that differences in levels of processing in the imagery task may account for these discrepancies. This study tested our hypothesis using two approaches. The first two experiments utilised the R/K paradigm to investigate the effects of these methods on familiarity-based and recollection-based recognition. The results demonstrated that familiarity was increased in the compound task, while recollection was increased in the imagery task. In the subsequent two experiments, an interference paradigm was employed to examine differences in semantic processing within the two tasks. The results showed that the compound task did not impact participants' inclination towards lures, while the imagery task led to a bias towards semantic lures over episodic lures, suggesting that the two encodings in the imagery task involve different levels of semantic processing. These results support our hypothesis and underscore the importance of carefully choosing comparisons that account for other variables in the study of unitisation.


Assuntos
Rememoração Mental , Semântica , Humanos , Reconhecimento Psicológico , Imagens, Psicoterapia
12.
Plant Cell Rep ; 43(3): 66, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341387

RESUMO

KEY MESSAGE: We used transcriptomic and proteomic association analysis to reveal the critical genes/proteins at three key flower bud differentiation stages and overexpression of CpFPA1 in Arabidopsis resulted in earlier flowering. Wintersweet (Chimonanthus praecox), a rare winter-flowering woody plant, is well known for its unique blooming time, fragrance and long flowering period. However, the molecular mechanism of flowering in C. praecox remains poorly unclear. In this study, we used transcriptomic and proteomic association analysis to reveal the critical genes/proteins at three key flower bud (FB) differentiation stages (FB.Apr, FB.May and FB.Nov) in C. praecox. The results showed that a total of 952 differential expressed genes (DEGs) and 40 differential expressed proteins (DEPs) were identified. Gene ontology (GO) enrichment revealed that DEGs in FB.Apr/FB.May comparison group were mainly involved in metabolic of biological process, cell and cell part of cellular component and catalytic activity of molecular function. In the EuKaryotic Orthologous Groups (KOG) functional classification, DEPs were predicted mainly in the function of general function prediction only (KOG0118), post-translational modification, protein turnover and chaperones. The autonomous pathway genes play an essential role in the floral induction. Based on transcriptome and proteome correlation analysis, six candidate genes associated with the autonomous pathway were identified, including FPA1, FPA2a, FPA2b, FCA, FLK, FY. Furthermore, CpFPA1 was isolated and functionally characterized, and ectopic expression of CpFPA1 in Arabidopsis Columbia (Col-0) resulted in earlier flowering. These data could contribute to understand the function of CpFPA1 for floral induction and provide information for further research on the molecular mechanisms of flowering in wintersweet.


Assuntos
Arabidopsis , Transcriptoma , Transcriptoma/genética , Proteoma/genética , Proteoma/metabolismo , Flores/genética , Flores/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteômica , Regulação da Expressão Gênica de Plantas
13.
Cancer ; 130(S8): 1424-1434, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38217532

RESUMO

BACKGROUND: Immunohistochemistry (IHC) is an essential technique in surgical and clinical pathology for detecting diagnostic, prognostic, and predictive biomarkers for personalized cancer therapy. However, the lack of standardization and reference controls results in poor reproducibility, and a reliable tool for IHC quantification is urgently required. The objective of this study was to describe a novel approach in which H3F3B (histone H3, family 3B) can be used as an internal reference standard to quantify protein expression levels using IHC. METHODS: The authors enrolled 89 patients who had human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). They used a novel IHC-based assay to measure protein expression using H3F3B as the internal reference standard. H3F3B was uniformly expressed at the protein level in all tumor regions in cancer tissues. HER2 expression levels were measured with the H-score using HALO software. RESULTS: Kaplan-Meier analysis indicated that, among patients who had HER2-positive BC in The Cancer Genome Atlas data set and the authors' data set, the subgroup with low HER2 expression had a significantly better prognosis than the subgroup with high HER2 expression. Furthermore, the authors observed that HER2 expression levels were precisely evaluated using the proposed method, which can classify patients who are at higher risk of HER2-positive BC to receive trastuzumab-based adjuvant therapy. Dual-color IHC with H3F3B is an excellent tool for internal and external quality control of HER2 expression assays. CONCLUSIONS: The proposed IHC-based quantification method accurately assesses HER2 expression levels and provides insights for predicting clinical prognosis in patients with HER2-positive BC who receive trastuzumab-based adjuvant therapy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Histonas , Imuno-Histoquímica , Reprodutibilidade dos Testes , Receptor ErbB-2/genética , Trastuzumab/uso terapêutico , Padrões de Referência , Biomarcadores Tumorais/metabolismo
14.
ACS Nano ; 18(1): 1226-1236, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38153997

RESUMO

Dielectric elastomer transducers (DETs), with a dielectric elastomer (DE) film sandwiched between two compliant electrodes, are highly sought after in the fields of soft robotics, energy harvesting, and human-machine interaction. To achieve a high-performance DET, it is essential to develop electrodes with high conductivity, strain-insensitive resistance, and adaptability. Herein, we design an electrode (Supra-LMNs) based on multiple dynamic bond cross-linked supramolecular networks (Ns) and liquid metal (LM), which realizes high conductivity (up to 16,000 S cm-1), negligible resistance changes at high strain (1.3-fold increase at 1000% strain), instantaneous self-healability at ambient temperature, and rapid recycling. The conductive pathway can be activated through simple friction by transmitting stress through the silver nanowires (AgNWs) and cross-linking sites of LM particles. This method is especially attractive for printing circuits on flexible substrates, especially DE films. Utilized as dielectric elastomer generator (DEG) electrodes, it reduces the charge loss by 3 orders of magnitude and achieves high generating energy density and energy conversion efficiency on a low-resistance load. Additionally, serving as sensor (DES) and actuator (DEA) electrodes, it enables a highly sensitive sensing capability and complex interaction.

15.
Zookeys ; 1176: 37-53, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654980

RESUMO

Accurate taxonomical identification is an extremely important basis for stick insect research, including evolutionary biology but also applied biology such as pest control. In addition, genetic methods are a valuable identification auxiliary technology at present. Therefore, this paper used morphological and molecular data to investigate five stick insect specimens from the genus Cnipsomorpha in Yunnan, successfully identifying two new species: Cnipsomorphayunnanensis Xu, Jiang & Yang, sp. nov. and C.yuxiensis Xu, Jiang & Yang, sp. nov. A phylogenetic tree was constructed through their 28S and COI genes in order to infer the phylogenetic position of the two new species. Photographs of the new species and a key to all known Cnipsomorpha species are provided.

16.
Psychol Res Behav Manag ; 16: 3717-3726, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37700881

RESUMO

Introduction: Interpersonal relationship serve as crucial of social support and a sense of security for left-behind children, playing a compensatory role in mitigating the absence of familial affection. Interpersonal distress can significantly impact their mental well-being. Although previous research has established a connection between empathy and interpersonal distress, the mechanisms by which empathy triggers interpersonal distress, as well as potential gender-based variations in this relationship, remain elusive. To bridge this gap in knowledge, this study investigates the mediating influence of emotion regulation and the moderating impact of gender in the relationship between empathy and interpersonal distress. Methods: A total of 713 rural left-behind children completed the Interpersonal Reactivity Index scale, Emotion Regulation Competence Scale, and Interpersonal Relationship Assessment Scale. Results: Pearson correlation analyses suggested strong significant correlations among empathy, emotion regulation ability, and interpersonal distress. Path analyses indicated that emotion regulation ability mediated the relationship between empathy and interpersonal distress. Furthermore, hierarchical regression analyses suggest a moderating effect of gender in the relationship between empathy and emotion regulation ability. Discussion: The present study reveals the role of emotion regulation ability and gender in the relationship between empathy and interpersonal distress, which has important theoretical and practical implications for the prevention and intervention of interpersonal distress in left-behind children. Moreover, it may strengthen the relationship between peer and teacher at school, and improve the quality of parent-child communication at home.

17.
J Nat Prod ; 86(10): 2348-2359, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37737089

RESUMO

Eleven diterpenoids, wulfenioidins D-N (1-11), classified into five distinct carbon skeletons with one unreported framework, and four modified abietane diterpenoids were isolated from the whole plant of Orthosiphon wulfenioides. The structures and absolute configurations were characterized by spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism analyses. Compounds 3 and 5 exhibited activity against Zika virus (ZIKV) with EC50 values of 8.07 and 8.50 µM, respectively, and showed no significant cytotoxicity toward Vero cells at 100 µM. Western blot and immunofluorescence experiments showed that compounds 3 and 5 interfered with the replication of the ZIKV by inhibiting the expression of the ZIKV envelope (E) protein.


Assuntos
Diterpenos , Orthosiphon , Infecção por Zika virus , Zika virus , Animais , Chlorocebus aethiops , Células Vero , Diterpenos/química , Estrutura Molecular
18.
Nano Lett ; 23(16): 7599-7606, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37531458

RESUMO

Zero-dimensional organic-inorganic metal halide hybrids provide ideal bulk-crystal platforms for exploring the pressure engineering of electron-phonon coupling (EPC) and self-trapped exciton (STE) emission at the molecular level. However, the low stiffness of inorganic clusters hinders the reversible tuning of these physical properties. Herein, we designed a Sb3+-doped metal halide with a high emission yield (89.4%) and high bulk modulus (35 GPa) that enables reversible and enhanced STE emission (20-fold) under pressure. The high lattice rigidity originates from the corner-shared cage-structured inorganic tetramers and ring-shaped organic ligands. Further, we reveal that the pressure-enhanced emission regime below 4.5 GPa is owing to the lattice hardening and preferably EPC strength reducing, while the pressure-insensitive emission regime within 4.5-8.5 GPa results from the enhanced intercluster Coulombic attraction force that resists intracluster compression. These results provide insights into the structure-property relation and molecular engineering of zero-dimensional metal halides toward wide-band and pressure-sensitive light sources.

19.
Fitoterapia ; 169: 105614, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37463646

RESUMO

Four new diterpenoids (1-4) and sixteen known diterpenoids (5-20) were purified from the whole plant of Euphorbia helioscopia L. Compounds 1 and 2 were rhamofolane diterpenoids with a 5/7/6 tricyclic systems, compound 3 was a lathyranes diterpenoid, and compound 4 was a jathophanes diterpenoid. The isolated compounds were tested for their cytotoxicity and anti-Zika virus properties, and compounds 9 and 15 showed low cytotoxicity and strong anti-Zika virus properties with EC50 2.63 and 5.94 µM, respectively. Further, the inhibitory effects of compounds on protein levels were determined using Western blotting and immunofluorescence assays.


Assuntos
Diterpenos , Euphorbia , Estrutura Molecular , Diterpenos/farmacologia
20.
Nano Lett ; 23(8): 3493-3500, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37023469

RESUMO

Indium selenide (InSe) exhibits high lattice compressibility and an extraordinary capability of tailoring the optical band gap under pressure beyond other 2D materials. Herein, by applying hydrostatic pressure via a diamond anvil cell, we revealed an anisotropic deformation dynamic and efficient manipulation of near-infrared light emission in thin-layered InSe strongly correlated to layer numbers (N = 5-30). As N > 20, the InSe lattice is compressed in all directions, and the intralayer compression leads to widening of the band gap, resulting in an emission blue shift (∼120 meV at 1.5 GPa). In contrast, as N ≤ 15, an efficient emission red shift is observed from band gap shrinkage (rate of 100 meV GPa-1), which is attributed to the predominant uniaxial interlayer compression because of the high strain resistance along the InSe-diamond interface. These findings advance the understanding of pressure-induced lattice deformation and optical transition evolution in InSe and could be applied to other 2D materials.

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