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1.
Environ Sci Technol ; 58(19): 8404-8416, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38698567

RESUMO

In densely populated urban areas, PM2.5 has a direct impact on the health and quality of residents' life. Thus, understanding the disparities of PM2.5 is crucial for ensuring urban sustainability and public health. Traditional prediction models often overlook the spillover effects within urban areas and the complexity of the data, leading to inaccurate spatial predictions of PM2.5. We propose Deep Support Vector Regression (DSVR) that models the urban areas as a graph, with grid center points as the nodes and the connections between grids as the edges. Nature and human activity features of each grid are initialized as the representation of each node. Based on the graph, DSVR uses random diffusion-based deep learning to quantify the spillover effects of PM2.5. It leverages random walk to uncover more extensive spillover relationships between nodes, thereby capturing both the local and nonlocal spillover effects of PM2.5. And then it engages in predictive learning using the feature vectors that encapsulate spillover effects, enhancing the understanding of PM2.5 disparities and connections across different regions. By applying our proposed model in the northern region of New York for predictive performance analysis, we found that DSVR consistently outperforms other models. During periods of PM2.5 surges, the R-square of DSVR reaches as high as 0.729, outperforming non-spillover models by 2.5 to 5.7 times and traditional spatial metric models by 2.2 to 4.6 times. Therefore, our proposed model holds significant importance for understanding disparities of PM2.5 air pollution in urban areas, taking the first steps toward a new method that considers both the spillover effects and nonlinear feature of data for prediction.


Assuntos
Poluição do Ar , Material Particulado , Máquina de Vetores de Suporte , Humanos , Poluentes Atmosféricos/análise , Cidades , Monitoramento Ambiental
2.
Sensors (Basel) ; 24(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38610323

RESUMO

The mature processes of metal oxide semiconductors (MOS) have attracted considerable interest. However, the low sensitivity of metal oxide semiconductor gas sensors is still challenging, and constrains its practical applications. Bimetallic nanoparticles are of interest owing to their excellent catalytic properties. This excellent feature of bimetallic nanoparticles can solve the problems existing in MOS gas sensors, such as the low response, high operating temperature and slow response time. To enhance acetone sensing performance, we successfully synthesized Au-Pd/ZnO nanorods. In this work, we discovered that Au-Pd nanoparticles modified on ZnO nanorods can remarkably enhance sensor response. The Au-Pd/ZnO gas sensor has long-term stability and an excellent response/recovery process. This excellent sensing performance is attributed to the synergistic catalytic effect of bimetallic AuPd nanoparticles. Moreover, the electronic and chemical sensitization of noble metals also makes a great contribution. This work presents a simple method for preparing Au-Pd/ZnO nanorods and provides a new solution for the detection of acetone based on metal oxide semiconductor.

3.
Nat Nanotechnol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649747

RESUMO

Perovskite quantum dots (QDs) are promising for various photonic applications due to their high colour purity, tunable optoelectronic properties and excellent solution processability. Surface features impact their optoelectronic properties, and surface defects remain a major obstacle to progress. Here we develop a strategy utilizing diisooctylphosphinic acid-mediated synthesis combined with hydriodic acid-etching-driven nanosurface reconstruction to stabilize CsPbI3 QDs. Diisooctylphosphinic acid strongly adsorbs to the QDs and increases the formation energy of halide vacancies, enabling nanosurface reconstruction. The QD film with nanosurface reconstruction shows enhanced phase stability, improved photoluminescence endurance under thermal stress and electric field conditions, and a higher activation energy for ion migration. Consequently, we demonstrate perovskite light-emitting diodes (LEDs) that feature an electroluminescence peak at 644 nm. These LEDs achieve an external quantum efficiency of 28.5% and an operational half-lifetime surpassing 30 h at an initial luminance of 100 cd m-2, marking a tenfold improvement over previously published studies. The integration of these high-performance LEDs with specifically designed thin-film transistor circuits enables the demonstration of solution-processed active-matrix perovskite displays that show a peak external quantum efficiency of 23.6% at a display brightness of 300 cd m-2. This work showcases nanosurface reconstruction as a pivotal pathway towards high-performance QD-based optoelectronic devices.

4.
Sheng Wu Gong Cheng Xue Bao ; 40(4): 1102-1119, 2024 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-38658152

RESUMO

HSP70 protein, as an important member of the heat shock protein (HSP) family, plays an important role in plant growth, development, and response to biotic and abiotic stresses. In order to explore the role of HSP70 gene family members in Litchi chinensis under low temperature, high temperature, drought, and salt stress, bioinformatics methods were used to identify the HSP70 gene family members within the entire L. chinensis genome. The expression of these genes under various abiotic stresses was then detected using quantitative real-time PCR (qRT-PCR). The results showed that the LcHSP70 gene family consisted of 18 members, which were unevenly distributed across ten L. chinensis chromosomes. The LcHSP70 protein contained 479-851 amino acids, with isoelectric points ranging from 5.07 to 6.95, and molecular weights from 52.44 kDa to 94.07 kDa. The predicted subcellular localization showed that LcHSP70 protein was present in the nucleus, cytoplasm, endoplasmic reticulum, mitochondria, and chloroplast. Phylogenetic analysis divided the LcHSP70 proteins into five subgroups, namely Ⅰ, Ⅱ, Ⅲ, Ⅳ, and Ⅵ. The promoter regions of the LcHSP70 genes contained various cis-acting elements related to plant growth, development, hormone response, and stress response. Moreover, the expression of LcHSP70 genes displayed distint tissue-specific expression level, categorized into universal expression and specific expression. From the selected 6 LcHSP70 genes (i.e., LcHSP70-1, LcHSP70-5, LcHSP70-10, LcHSP70-14, LcHSP70-16, and LcHSP70-18), their relative expression levels were assessed under different abiotic stresses using qRT-PCR. The results indicated that the gene family members exhibited diverse responses to low temperature, high temperature, drought, and salt stress, with significant variations in their expression levels across different time periods. These results provide a foundation for further exploration of the function of the LcHSP70 gene family.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico HSP70 , Litchi , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Litchi/genética , Litchi/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/biossíntese , Família Multigênica , Estresse Salino/genética
5.
ACS Appl Mater Interfaces ; 16(15): 19742-19750, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563423

RESUMO

Perovskites have great potential for optoelectronic applications due to their high photoluminescence quantum yield, large absorption coefficient, great defect tolerance, and adjustable band gap. Perovskite heterostructures may further enhance the performance of optoelectronic devices. So far, however, most of perovskite heterostructures are fabricated by mechanical stacking or spin coating, which could introduce a large number of defects or impurities at the heterointerface owing to the random stacking process. Herein, we report the epitaxial growth of CsPbBr3 pyramids/CdS nanobelt heterostructures via a 2-step vapor deposition route. The CsPbBr3 triangular pyramids are well aligned on the surface of CdS nanobelts with the epitaxial relationships of (0-22)CsPbBr3||(1-20)CdS and (-211)CsPbBr3||(002)CdS. Time-resolved photoluminescence results reveal that effective charge transfer occurred at the heterointerface, which can be attributed to the type-II band arrangement. Theoretical simulations reveal that the unique CsPbBr3 pyramids/CdS nanobelt structure facilitates diminishing the reflection losses and enhancing the light absorption. The photodetector based on these CsPbBr3 pyramids/CdS nanobelt heterostructures exhibited an ultrahigh photoswitching ratio of 2.14 × 105, a high responsivity up to 4.07 × 104 A/W, a high detectivity reaching 1.36 × 1013 Jones, fast photoresponses (τrise = 472 µs and τdecay = 894 µs), low dark current, and suppressed hysteresis.

6.
ACS Nano ; 18(15): 10609-10617, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38569090

RESUMO

Controlling interfacial reactions is critical for zinc oxide (ZnO)-based inverted perovskite light-emitting diodes (PeLEDs), boosting the external quantum efficiency (EQE) of the near-infrared device to above 20%. However, violent interfacial reactions between the bromine-based perovskites and ZnO-based films severely limit the performance of inverted green PeLEDs, whose efficiency and stability lag far behind those of their near-infrared counterparts. Here, a controllable interfacial amidation between the bromine-based perovskites and magnesium-doped ZnO (ZnMgO) film utilizing caprylyl sulfobetaine (SFB) is realized. The SFB molecules strongly interact with formamidinium bromide, decelerating the amidation reaction between formamidinium and carboxylate groups on the ZnMgO film, thus regulating the crystallization of FAPbBr3. Combined with the passivation of benzylamine, a FAPbBr3 bulk film directly deposited on a ZnMgO substrate with single-crystal characteristics is obtained, exhibiting a high photoluminescence quantum yield of above 80%. The resultant PeLEDs demonstrate a peak EQE of exceeding 20% at a high luminance of 120,000 cd m-2 and a half lifetime of 26 min at 11,000 cd m-2, representing the state-of-the-art inverted green electroluminescence. This work resolves the crucial issues of violent interfacial reactions and provides a strategy toward inverted green PeLEDs with outstanding performance.

7.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1310-1317, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621978

RESUMO

This study investigated the effect of Erchen Decoction(ECD) on the prevention of non-alcoholic steatohepatitis(NASH) in mice and explored its possible mechanism, so as to provide scientific data for the clinical application of ECD in the prevention of NASH. C57BL/6 male mice were randomly divided into normal group(methionine and choline supplement, MCS), model group(methionine and choline deficient, MCD), low-dose ECD group(ECD_L, 6 g·kg~(-1)), medium-dose ECD group(ECD_M, 12 g·kg~(-1)), and high-dose ECD group(ECD_H, 24 g·kg~(-1)), with eight mice in each group. The MCS group was fed with an MCS diet, and the other groups were fed with an MCD diet. The mice in each group were given corresponding diets, but the drug intervention group was given low-, medium-, and high-dose ECD(10 mL·kg~(-1)·d~(-1)) by intragastric administration for six weeks on the basis of MCD diet feeding, and the mice could eat and drink freely during the whole experiment. At the end of the experiment, mice were fasted overnight(12 h) and were anesthetized with 20% urethane. Thereafter, the blood and liver tissue were collected. The serum was used to detect the levels of alanine aminotransferase(ALT), aspartate aminotransaminase(AST), interleukin-1ß(IL-1ß), interleukin-6(IL-6), interleukin-10(IL-10), and tumor necrosis factor-α(TNF-α). Liver tissue was processed by hematoxylin-eosin(HE) staining and used for hepatic histological analysis and detection of the expression levels of genes and proteins related to nuclear factor erythroid 2-related factor 2/glutathione peroxidase 4(Nrf2/GPX4) pathway by real-time quantitative reverse transcriptase-polymerase chain reaction(RT-qPCR) and Western blot analysis, respectively. The results showed that compared with the MCS group, the MCD group showed higher serum ALT and AST levels; the HE staining exhibited fat vacuoles and obvious inflammatory cell infiltration in liver tissue; serum IL-1ß, IL-6, and TNF-α levels were significantly increased, and the serum IL-10 level was significantly decreased. The mRNA expressions of fatty acid synthase(FASN), monocyte chemoattractant protein-1(MCP-1), and IL-1ß in liver tissue were significantly up-regulated, while those of GPX4, Nrf2, and NAD(P)H:quinine oxidoreductase(NQO1) were significantly down-regulated. Compared with the MCD group, the serum ALT and AST levels of ECD_M and ECD_H groups were significantly decreased, and the AST level in the ECD_L group was significantly decreased. The number of fat vacuoles and the degree of inflammatory cell infiltration in liver tissue were improved; serum IL-1ß, IL-6, and TNF-α levels were significantly decreased, but the serum IL-10 level was significantly increased only in the ECD_H group. The mRNA expressions of FASN, MCP-1, and IL-1ß in liver tissue were significantly down-regulated, and those of GPX4 and NQO1 were significantly up-regulated. The mRNA expressions of Nrf2 in ECD_M and ECD_H groups were significantly up-regulated. Western blot results showed that compared with the MCD group, the protein expression levels of Nrf2 and GPX4 in each group were significantly increased after ECD administration, and the protein expression level of FASN was significantly decreased; the protein expression of NQO1 was increased in ECD_M and ECD_H groups. In summary, ECD can reduce hepatic lipid accumulation, oxidative stress, liver inflammation, and liver injury in NASH mice, which may be related to the activation of the Nrf2/GPX4 pathway.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Masculino , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Metionina/metabolismo , Metionina/farmacologia , Interleucina-10/genética , Colina/metabolismo , Colina/farmacologia , Colina/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Camundongos Endogâmicos C57BL , Fígado , Racemetionina/metabolismo , Racemetionina/farmacologia , Dieta , RNA Mensageiro/metabolismo
8.
Biomolecules ; 14(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38672421

RESUMO

Captivity is an important and efficient technique for rescuing endangered species. However, it induces infertility, and the underlying mechanism remains obscure. This study used the plateau pika (Ochotona curzoniae) as a model to integrate physiological, metagenomic, metabolomic, and transcriptome analyses and explore whether dysbiosis of the gut microbiota induced by artificial food exacerbates infertility in captive wild animals. Results revealed that captivity significantly decreased testosterone levels and the testicle weight/body weight ratio. RNA sequencing revealed abnormal gene expression profiles in the testicles of captive animals. The microbial α-diversity and Firmicutes/Bacteroidetes ratio were drastically decreased in the captivity group. Bacteroidetes and Muribaculaceae abundance notably increased in captive pikas. Metagenomic analysis revealed that the alteration of flora increased the capacity for carbohydrate degradation in captivity. The levels of microbe metabolites' short-chain fatty acids (SCFAs) were significantly high in the captive group. Increasing SCFAs influenced the immune response of captivity plateau pikas; pro-inflammatory cytokines were upregulated in captivity. The inflammation ultimately contributed to male infertility. In addition, a positive correlation was observed between Gastranaerophilales family abundance and testosterone concentration. Our results provide evidence for the interactions between artificial food, the gut microbiota, and male infertility in pikas and benefit the application of gut microbiota interference in threatened and endangered species.


Assuntos
Disbiose , Microbioma Gastrointestinal , Infertilidade Masculina , Lagomorpha , Testosterona , Animais , Masculino , Disbiose/microbiologia , Disbiose/metabolismo , Infertilidade Masculina/microbiologia , Infertilidade Masculina/metabolismo , Testosterona/metabolismo , Lagomorpha/microbiologia , Testículo/microbiologia , Testículo/metabolismo , Ácidos Graxos Voláteis/metabolismo
9.
Angew Chem Int Ed Engl ; : e202406767, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682392

RESUMO

Cyclic sulfones have demonstrated important applications in drug discovery. However, the catalytic and enantioselective synthesis of chiral cyclic sulfones remains challenging. Herein, we develop nickel-catalyzed regiodivergent and enantioselective hydroalkylation of sulfolenes to streamline the synthesis of chiral alkyl cyclic sulfones. The method has broad scope and high functional group tolerance. The regioselectivity can be controlled by ligands only. A neutral PYROX ligand favors C3-alkylation whereas an anionic BOX ligand favors C2-alkylation. This control is kinetic in origin as the C2-bound Ni intermediates are always thermodynamically more stable. Reactivity study of a wide range of relevant Ni intermediates reveal a NiI/NiIII catalytic cycle with a NiII-H species as the resting state. The regio- and enantio-determining step is the insertion of this NiII-H species into 2-sulfolene. This work provides an efficient catalytic method for the synthesis of an important class of organic compounds and enhances the mechanistic understanding of Ni-catalyzed stereoselective hydroalkylation.

10.
Sci Total Environ ; 928: 172461, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38615767

RESUMO

Wildfire smoke greatly impacts regional atmospheric systems, causing changes in the behavior of pollution. However, the impacts of wildfire smoke on pollution behavior are not easily quantifiable due to the complex nature of atmospheric systems. Air pollution correlation networks have been used to quantify air pollution behavior during ambient conditions. However, it is unknown how extreme pollution events impact these networks. Therefore, we propose a multidimensional air pollution correlation network framework to quantify the impacts of wildfires on air pollution behavior. The impacts are quantified by comparing two time periods, one during the 2023 Canadian wildfires and one during normal conditions with two complex network types for each period. In this study, the value network represents PM2.5 concentrations and the rate network represents the rate of change of PM2.5 concentrations. Wildfires' impacts on air pollution behavior are captured by structural changes in the networks. The wildfires caused a discontinuous phase transition during percolation in both network types which represents non-random organization of the most significant spatiotemporal correlations. Additionally, wildfires caused changes to the connectivity of stations leading to more interconnected networks with different influential stations. During the wildfire period, highly polluted areas are more likely to form connections in the network, quantified by an 86 % and 19 % increase in the connectivity of the value and rate networks respectively compared to the normal period. In this study, we create novel understandings of the impacts of wildfires on air pollution correlation networks, show how our method can create important insights into air pollution patterns, and discuss potential applications of our methodologies. This study aims to enhance capabilities for wildfire smoke exposure mitigation and response strategies.

11.
Sci Rep ; 14(1): 8106, 2024 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582913

RESUMO

Wheat head detection and counting using deep learning techniques has gained considerable attention in precision agriculture applications such as wheat growth monitoring, yield estimation, and resource allocation. However, the accurate detection of small and dense wheat heads remains challenging due to the inherent variations in their size, orientation, appearance, aspect ratios, density, and the complexity of imaging conditions. To address these challenges, we propose a novel approach called the Oriented Feature Pyramid Network (OFPN) that focuses on detecting rotated wheat heads by utilizing oriented bounding boxes. In order to facilitate the development and evaluation of our proposed method, we introduce a novel dataset named the Rotated Global Wheat Head Dataset (RGWHD). This dataset is constructed by manually annotating images from the Global Wheat Head Detection (GWHD) dataset with oriented bounding boxes. Furthermore, we incorporate a Path-aggregation and Balanced Feature Pyramid Network into our architecture to effectively extract both semantic and positional information from the input images. This is achieved by leveraging feature fusion techniques at multiple scales, enhancing the detection capabilities for small wheat heads. To improve the localization and detection accuracy of dense and overlapping wheat heads, we employ the Soft-NMS algorithm to filter the proposed bounding boxes. Experimental results indicate the superior performance of the OFPN model, achieving a remarkable mean average precision of 85.77% in oriented wheat head detection, surpassing six other state-of-the-art models. Moreover, we observe a substantial improvement in the accuracy of wheat head counting, with an accuracy of 93.97%. This represents an increase of 3.12% compared to the Faster R-CNN method. Both qualitative and quantitative results demonstrate the effectiveness of the proposed OFPN model in accurately localizing and counting wheat heads within various challenging scenarios.


Assuntos
Agricultura , Triticum , Algoritmos , Tratos Piramidais , Alocação de Recursos
12.
NPJ Regen Med ; 9(1): 13, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519518

RESUMO

Neural progenitor cells (NPCs) derived from human pluripotent stem cells(hPSCs) provide major cell sources for repairing damaged neural circuitry and enabling axonal regeneration after spinal cord injury (SCI). However, the injury niche and inadequate intrinsic factors in the adult spinal cord restrict the therapeutic potential of transplanted NPCs. The Sonic Hedgehog protein (Shh) has crucial roles in neurodevelopment by promoting the formation of motorneurons and oligodendrocytes as well as its recently described neuroprotective features in response to the injury, indicating its essential role in neural homeostasis and tissue repair. In this study, we demonstrate that elevated SHH signaling in hNPCs by inhibiting its negative regulator, SUFU, enhanced cell survival and promoted robust neuronal differentiation with extensive axonal outgrowth, counteracting the harmful effects of the injured niche. Importantly, SUFU inhibition in NPCs exert non-cell autonomous effects on promoting survival and neurogenesis of endogenous cells and modulating the microenvironment by reducing suppressive barriers around lesion sites. The combined beneficial effects of SUFU inhibition in hNPCs resulted in the effective reconstruction of neuronal connectivity with the host and corticospinal regeneration, significantly improving neurobehavioral recovery in recipient animals. These results demonstrate that SUFU inhibition confers hNPCs with potent therapeutic potential to overcome extrinsic and intrinsic barriers in transplantation treatments for SCI.

13.
J Neurotrauma ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38425191

RESUMO

Severe traumatic brain injury (sTBI) is a prominent contributor to both morbidity and mortality in the elderly population. The monitoring of intracranial pressure (ICP) is crucial in the management of sTBI patients. Nevertheless, the appropriate timing for the placement of ICP monitor in elderly sTBI patients remains uncertain. To determine the optimal timing for the placement of ICP monitor in elderly sTBI patients, in this retrospective cohort study, we collected data from elderly patients (> 65 years) who suffered sTBI and received ICP monitors at Tangdu Hospital, The Fourth Military Medical University, between January 2011 and December 2021. To examine the relationship between the time of ICP monitor placement and in-hospital mortality, we conducted a multi-variate-adjusted restricted cubic spline (RCS) analysis. Additionally, logistic regression analysis was applied to further analyze the influencing factors contributing to early or late ICP monitor placements. A total of 283 eligible elderly TBI patients were included in the current analysis. The in-hospital mortality rate was 73 out of 283 (26%). The RCS analysis demonstrated an inverted U-shaped curve in the relationship between the timing of ICP monitor placement and in-hospital mortality. For the elderly sTBI patient cohort, 6 h was identified as the crucial moment for the treatment strategy. In addition, the protective time window for ICP placement was less than 4.92 h for the GCS 3-5 group, and less than 8.26 h for the GCS 6-8 group. However, the clinical benefit of ICP placement decreased gradually over time. The relationship between ICP placement and in-hospital mortality was non-linear, exhibiting an inverted U-shaped curve in elderly patients with sTBI. For elderly patients with sTBI, early (≤ 6 h) ICP placement was associated with reduced in-hospital mortality. The clinical benefit of ICP placement decreased beyond the optimal time window.

14.
Nano Lett ; 24(12): 3750-3758, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38488747

RESUMO

Semiconductor planar nanowire arrays (PNAs) are essential for achieving large-scale device integration. Direct heteroepitaxy of PNAs on a flat substrate is constrained by the mismatch in crystalline symmetry and lattice parameters between the substrate and epitaxial nanowires. This study presents a novel approach termed "self-competitive growth" for heteroepitaxy of CsPbBr3 PNAs on mica. The key to inducing the self-competitive growth of CsPbBr3 PNAs on mica involves restricting the nucleation of CsPbBr3 nanowires in a high-adsorption region, which is accomplished by overlaying graphite sheets on the mica surface. Theoretical calculations and experimental results demonstrate that CsPbBr3 nanowires oriented perpendicular to the boundary of the high-adsorption area exhibit greater competitiveness in intercepting the growth of nanowires in the other two directions, resulting in PNAs with a consistent orientation. Moreover, these PNAs exhibit low-threshold and stable amplified spontaneous emission under one-, two-, and three-photon excitation, indicating their potential for an integrated laser array.

15.
J Colloid Interface Sci ; 663: 157-166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38401437

RESUMO

Perovskite nanoplatelets (NPLs), as a promising material to achieve pure blue emission, have attracted significant attention in high gamut displays. However, the high surface-to-volume ratio and the loosely connected ligands of NPLs make them susceptible to degradation from light, air and heat. As a result, NPLs often exhibit low photoluminescence (PL) intensity and instability. Here, an Mn-ligand passivation strategy is proposed, in which Mn-doped DMAPbBr3 is used as a precursor. During the perovskite transformation, Mn2+ ions migrate from the lattice of DMAPbBr3 to the surface of CsPbBr3 NPLs, which have strong binding forces with ligands. The final products Mn-CsPbBr3 (M-CPB) NPLs are then acquired by the ligand-induced ripening growth process, which not only exhibit pure blue emission with narrow full width at half maximum (FWHM), but also possess near-unity PL quantum yields (QYs). Besides, M-CPB NPLs show excellent stability due to the strong Mn-ligand passivation layer. Based on the new growth mechanism discovery, the reaction time can be shortened to several minutes by heating. The innovative growth model proposed in this work will provide a paradigm for designing and optimizing future synthesis schemes.

16.
Angew Chem Int Ed Engl ; 63(17): e202401575, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38357753

RESUMO

A general approach to the direct deoxygenative transformation of primary, secondary, and tertiary alcohols has been developed. It undergoes through phosphoranyl radical intermediates generated by the addition of exogenous iodine radical to trivalent alkoxylphosphanes. Since these alkoxylphosphanes are readily in situ obtained from alcohols and commercially available, inexpensive chlorodiphenylphosphine, a diverse range of alcohols with various functional groups can be utilized to proceed deoxygenative cross-couplings with alkenes or aryl iodides. The selective transformation of polyhydroxy substrates and the rapid synthesis of complex organic molecules are also demonstrated with this method.

17.
Dig Liver Dis ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38320913

RESUMO

BACKGROUND AND AIMS: Giant esophageal leiomyoma usually requires a thoracotomy or thoracoscopic surgery, which is more invasive than an endoscopic treatment. The purpose of this study is to evaluate the efficacy and safety of piecemeal submucosal tunneling endoscopic resection (P-STER) for giant leiomyoma originating from the muscularis propria (MP) layer of the esophagus. METHODS: This is a retrospective study. Patients with giant esophageal leiomyoma (transverse diameter ≥ 3 cm) who underwent P-STER were enrolled from November 2012 to May 2023. Clinical data and results were investigated. RESULTS: A total of 16 patients were enrolled for analysis. The lesion mean transverse diameter and longitudinal diameter were 4.22 ± 1.20 cm and 6.20 ± 1.57 cm, respectively. Our mean operation time was 195.38 ± 84.99 min. The mean number of piecemeal resected was 4.31 ± 2.36. An adverse event noted was an esophageal fistula that occurred in one case (6.25%) and was treated conservatively. The mean length of hospital stay was around 11.81 ± 7.30 days. The mean total hospitalization cost was U.S. dollars (USD) $5976.50 ± 2866.39. No recurrence or metastasis was found during the follow-up period. CONCLUSIONS: P-STER can be an effective and safe treatment for giant leiomyoma originating from the MP layer of the esophagus.

18.
ACS Sens ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38401047

RESUMO

Rapid and ultrasensitive detection of toxic gases at room temperature is highly desired in health protection but presents grand challenges in the sensing materials reported so far. Here, we present a gas sensor based on novel zero dimensional (0D)/two dimensional (2D) indium oxide (In2O3)/titanium carbide (Ti3C2Tx) Schottky heterostructures with a high surface area and rich oxygen vacancies for parts per billion (ppb) level nitrogen dioxide (NO2) detection at room temperature. The In2O3/Ti3C2Tx gas sensor exhibits a fast response time (4 s), good response (193.45% to 250 ppb NO2), high selectivity, and excellent cycling stability. The rich surface oxygen vacancies play the role of active sites for the adsorption of NO2 molecules, and the Schottky junctions effectively adjust the charge-transfer behavior through the conduction tunnel in the sensing material. Furthermore, In2O3 nanoparticles almost fully cover the Ti3C2Tx nanosheets which can avoid the oxidation of Ti3C2Tx, thus contributing to the good cycling stability of the sensing materials. This work sheds light on the sensing mechanism of heterojunction nanostructures and provides an efficient pathway to construct high-performance gas sensors through the rational design of active sites.

19.
Int J Mol Sci ; 25(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339030

RESUMO

The MADS-box protein is an important transcription factor in plants and plays an important role in regulating the plant abiotic stress response. In this study, a total of 94 MADS-box genes were predicted in the litchi genome, and these genes were widely distributed on all the chromosomes. The LcMADS-box gene family was divided into six subgroups (Mα, Mß, Mγ, Mδ, MIKC, and UN) based on their phylogenetical relationships with Arabidopsis, and the closely linked subgroups exhibited more similarity in terms of motif distribution and intron/exon numbers. Transcriptome analysis indicated that LcMADS-box gene expression varied in different tissues, which can be divided into universal expression and specific expression. Furthermore, we further validated that LcMADS-box genes can exhibit different responses to various stresses using quantitative real-time PCR (qRT-PCR). Moreover, physicochemical properties, subcellular localization, collinearity, and cis-acting elements were also analyzed. The findings of this study provide valuable insights into the MADS-box gene family in litchi, specifically in relation to stress response. The identification of hormone-related and stress-responsive cis-acting elements in the MADS-box gene promoters suggests their involvement in stress signaling pathways. This study contributes to the understanding of stress tolerance mechanisms in litchi and highlights potential regulatory mechanisms underlying stress responses.


Assuntos
Arabidopsis , Litchi , Genoma de Planta , Litchi/genética , Litchi/metabolismo , Proteínas de Domínio MADS/metabolismo , Família Multigênica , Filogenia , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
20.
J Mol Endocrinol ; 72(3)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38261314

RESUMO

Follicle-stimulating hormone (FSH) accelerates osteoporosis in postmenopausal women, while the underlying mechanism remains uncharacterized. N6-methyladenosine (m6A) is one of the most important regulations in the development of osteoporosis. In this study, we aimed to investigate the role of FSH in m6A modification and osteoclast function. Here, we showed that FSH upregulated m6A levels in osteoclasts via stimulating methyltransferase-like 3 (METTL3) protein expression. FSH enhanced osteoclast migration, while the knockdown of METTL3 eliminated this enhancement. Both MeRIP-seq and RNA sequencing identified that cathepsin K (CTSK) is the potential downstream target of METTL3. Knockdown of CTSK reduced FSH-upregulated osteoclast migration. Furthermore, silencing METTL3 decreased CTSK mRNA stability. Finally, FSH induced phosphorylation of cyclic-AMP response element-binding protein (CREB), while silencing of CREB attenuated the effects of FSH on the promoter transcriptional activity of Mettl3 and CTSK/METTL3 protein. Taken together, these findings indicate that FSH promotes osteoclast migration via the CREB/METTL3/CTSK signaling pathway, which may provide a potential target for suppressing osteoclast mobility and postmenopausal osteoporosis therapy.


Assuntos
Adenina/análogos & derivados , Osteoclastos , Osteoporose , Humanos , Feminino , Osteoclastos/metabolismo , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/metabolismo , Catepsina K/genética , Catepsina K/metabolismo , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo
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