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Organic molecules have been regarded as ideal candidates for near-infrared (NIR) optoelectronic active materials due to their customizability and ease of large-scale production. However, constrained by the intricate molecular design and severe energy gap law, the realization of optoelectronic devices in the second near-infrared (NIR (II)) region with required narrow band gaps presents more challenges. Herein, we have originally proposed a cocrystal strategy that utilizes intermolecular charge-transfer interaction to drive the redshift of absorption and emission spectra of a series BFXTQ (X = 0, 1, 2, 4) cocrystals, resulting in the spectra located at NIR (II) window and reducing the optical bandgap to â¼0.98 eV. Significantly, these BFXTQ-based optoelectronic devices can exhibit dual-mode optoelectronic characteristics. An investigation of a series of BFXTQ-based photodetectors exhibits detectivity (D*) surpassing 1013 Jones at 375 to 1064 nm with a maximum of 1.76 × 1014 Jones at 1064 nm. Moreover, the radiative transition of CT excitons within the cocrystals triggers NIR emission over 1000 nm with a photoluminescence quantum yield (PLQY) of â¼4.6% as well as optical waveguide behavior with a low optical-loss coefficient of 0.0097 dB/µm at 950 nm. These results promote the advancement of an emerging cocrystal approach in micro/nanoscale NIR multifunctional optoelectronics.
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Multicolor luminescence of organic fluorescent materials is an essential part of lighting and optical communication. However, the conventional construction of a multicolor luminescence system based on integrating multiple organic fluorescent materials of a single emission band remains complicated and to be improved. Herein, organic alloys (OAs) capable of full-color emission are synthesized based on charge transfer (CT) cocrystals. By adjusting the molar ratio of electron donors, the emission color of the OAs can be conveniently and continuously regulated in a wide visible range from blue (CIE: 0.187, 0.277), to green (CIE: 0.301, 0.550), and to red (CIE: 0.561, 0.435). The OAs show analogous 1D morphology with smooth surface, allowing for full-color waveguides with low optical-loss coefficient. Impressively, full-color optical displays are easily achieved through the OAs system with continuous emission, which shows promising applications in the field of optical display and promotes the development of organic photonics.
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Organic luminescent materials are indispensable in optoelectronic displays and solid-state luminescence applications. Compared with single-component, multi-component crystalline materials can improve optoelectronic characteristics. This work forms a series of full-spectrum tunable luminescent charge-transfer (CT) cocrystals ranging from 400 to 800 nm through intermolecular collaborative self-assembly. What is even more interesting is that o-TCP-Cor(x)-Pe(1-x), p-TCP-Cor(x)-Pe(1-x), and o-TCP-AN(x)-TP(1-x) alloys are prepared based on cocrystals by doping strategies, which correspondingly achieve the stepless color change from blue (CIE [0.22, 0.44]) to green (CIE [0.16, 0.14]), from green (CIE [0.27, 0.56]) to orange (CIE [0.58, 0.42]), from yellow (CIE [0.40, 0.57]) to red (CIE [0.65, 0.35]). The work provides an efficient method for precisely synthesizing new luminescent organic semiconductor materials and lays a solid foundation for developing advanced organic solid-state displays.
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In this work, a highly sensitive and selective method for detecting folic acid (FA) was developed using D-penicillamine (DPA) stabilized Ag/Cu alloy nanoclusters (DPA@Ag/Cu NCs). The yellow emission of DPA@Ag/Cu NCs was found to be quenched upon the addition of FA to the system. The fluorescence intensity quenching value demonstrated a linear relationship with FA concentrations ranging from 0.01 to 1200â µM, with a limit of detection (LOD) of 5.3â nM. Furthermore, the detection mechanism was investigated through various characterization analyses, including high resolution transmission electron microscopy, fluorescence spectra, ultraviolet-visible absorption spectra, and fluorescence lifetime. The results indicated that the fluorescence quenching induced by FA was a result of electron transfer from FA to the ligands of DPA@Ag/Cu NCs. The selectivity of the FA sensor was also evaluated, showing that common amino acids and inorganic ions had minimal impact on the detection of FA. Moreover, the standard addition method was successfully applied to detect FA in human serum, chewable tablets and FA tablets with promising results. The use of DPA@Ag/Cu NCs demonstrates significant potential for detecting FA in complex biological samples.
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Ligas , Cobre , Corantes Fluorescentes , Ácido Fólico , Penicilamina , Prata , Espectrometria de Fluorescência , Penicilamina/análise , Penicilamina/química , Penicilamina/sangue , Cobre/química , Ácido Fólico/análise , Ácido Fólico/química , Ácido Fólico/sangue , Prata/química , Humanos , Ligas/química , Corantes Fluorescentes/química , Limite de Detecção , Nanopartículas Metálicas/química , Comprimidos/análiseRESUMO
BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a progressive manifestation of nonalcoholic fatty liver disease (NAFLD) that can lead to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Despite the growing knowledge of NASH and HCC, the association between the two conditions remains to be fully explored. Bioinformatics has emerged as a valuable approach for identifying disease-specific feature genes, enabling advancements in disease prediction, prevention, and personalized treatment strategies. MATERIALS AND METHODS: In this study, we utilized CellChat, copy number karyotyping of aneuploid tumors (CopyKAT), consensus Non-negative Matrix factorization (cNMF), Gene set enrichment analysis (GSEA), Gene set variation analysis (GSVA), Monocle, spatial co-localization, single sample gene set enrichment analysis (ssGSEA), Slingshot, and the Scissor algorithm to analyze the cellular and immune landscape of NASH and HCC. Through the Scissor algorithm, we identified three cell types correlating with disease phenotypic features and subsequently developed a novel clinical prediction model using univariate, LASSO, and multifactor Cox regression. RESULTS: Our results revealed that macrophages are a significant pathological factor in the development of NASH and HCC and that the macrophage migration inhibitory factor (MIF) signaling pathway plays a crucial role in cellular crosstalk at the molecular level. We deduced three prognostic genes (YBX1, MED8, and KPNA2), demonstrating a strong diagnostic capability in both NASH and HCC. CONCLUSION: These findings shed light on the pathological mechanisms shared between NASH and HCC, providing valuable insights for the development of novel clinical strategies.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Neoplasias Hepáticas/patologia , Modelos Estatísticos , Prognóstico , Progressão da Doença , FibroseRESUMO
Nickel-catalyzed hydrocyanation of 1,3-butadiene with hydrogen cyanide gas is the predominant method for the synthesis of adiponitrile, which is an important precursor for polymer production. However, the use of fossil-derived alkenes raises environmental concerns, and hydrogen cyanide is highly volatile and extremely toxic. Herein, we report the use of biomass-derived 1,4-butanediol, as well as other primary alcohols, for photochemical synthesis of linear and branched nitriles and dinitriles, including adiponitrile, with 1,4-dicyanobenzene as the CN source. This mild, sustainable method does not require hydrogen cyanide gas or an air- or moisture-sensitive metal catalyst and is applicable for the production of dinitriles as precursors of diamines, which have potential utility for the development of novel polyamides.
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Saturated N-heterocycles are found in numerous bioactive natural products and are prevalent in pharmaceuticals and agrochemicals. While there are many methods for their synthesis, each has its limitations, such as scope and functional group tolerance. Herein, we describe a rhodium-catalyzed transfer hydrogenation of pyridinium salts to access N-(hetero)aryl piperidines. The reaction proceeds via a reductive transamination process, involving the initial formation of a dihydropyridine intermediate via reduction of the pyridinium ion with HCOOH, which is intercepted by water and then hydrolyzed. Subsequent reductive amination with an exogenous (hetero)aryl amine affords an N-(hetero)aryl piperidine. This reductive transamination method thus allows for access of N-(hetero)aryl piperidines from readily available pyridine derivatives, expanding the toolbox of dearomatization and skeletal editing.
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Guaianolide dimers represent a unique class of natural products with anticancer activities, but their low content in plants has limited in-depth pharmacological studies. Lavandiolide I is a guaianolide dimer isolated from Artemisia species, and had been synthesized on a ten-gram scale in four steps with 60 % overall yield, which showed potent antihepatoma activity on the HepG2, Huh7, and SK-Hep-1 cell lines with IC50 values of 12.1, 18.4, and 17.6 µM, respectively. To explore more active dimers, 33 lavandiolide I derivatives were designed, synthesized, and evaluated for their inhibitory activity on human hepatoma cell lines. Among them, 10 derivatives were more active than lavandiolide I and sorafenib on the three cell lines. The primary structure-activity relationship concluded that the introduction of aldehyde, ester, azide, amide, carbamate and urea functional groups at C-14' of the guaianolide dimer significantly enhanced the antihepatoma activity. Among these compounds, derivatives 25, 27, and 33 enhanced antihepatoma activity more than 1.2-5.8 folds than that of lavandiolide I, and demonstrated low toxicity to the human liver cell lines (THLE-2) and good safety profiles with selective index ranging from 1.3 to 3.4, while lavandiolide I was more toxic to THLE-2 cells. This work provides new insights into enhancing the antihepatoma efficacy and reducing the toxicity of sesquiterpenoid dimers.
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Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Sesquiterpenos de Guaiano , Humanos , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células , Neoplasias Hepáticas/tratamento farmacológico , Estrutura Molecular , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Sesquiterpenos de Guaiano/síntese química , Sesquiterpenos de Guaiano/química , Sesquiterpenos de Guaiano/farmacologiaRESUMO
The efficient single-step purification of ethylene from ternary C2 mixtures containing ethane and acetylene is challenging and demanding. Herein, we introduce a novel cerium-based metal-organic framework (MOF) of Ce-NTB-rtk synthesized via a ligand-conformer strategy. The Ce-NTB-rtk features a rare tetranuclear cerium cluster and 2D kgd layers pillared by a 3D rtl framework concomitant with an extraordinary (3,3,12)-c network. The compound encompasses microporous cavities replete with a nonpolar microenvironment. Gas sorption and breakthrough experiments demonstrate its superior affinity for C2H6 and C2H2 over C2H4, enabling effective single-step ethylene purification. Computational simulations reveal that preferential adsorptions are facilitated by different interaction strengths of C-H···O hydrogen bonds. The performance of Ce-NTB-rtk in separation selectivity and regeneration capacity makes it a promising candidate for sustainable and cost-effective ethylene purification, showcasing the potential of MOFs in advanced gas separation applications.
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Recently, ezetimibe (EZM) has been suggested to be a potent Nrf2 activator that is important for preventing oxidative stress. Interestingly, we found that its metabolite ezetimibe ketone (EZM-K) also has antioxidant effects. Thus, we investigated the role of EZM-K in preventing renal ischemiaâreperfusion injury (RIRI). Cultured NRK-52E cells were subjected to simulated IR with or without EZM-K. Rats were used to simulate in vivo experiments. EZM-K alleviated H2O2-induced apoptosis and reactive oxygen species (ROS) and upregulated Nrf2 and HO-1 levels in NRK-52E cells. A HO-1 and a Nrf2 inhibitor reversed the protective effects of EZM-K. In the rat RIRI model, pretreatment with EZM-K activated the Nrf2/HO-1 signaling pathway, suppressed tubular injury and inflammation, and improved renal function. EZM-K significantly prevented renal injury caused by ischemiaâreperfusion via the Nrf2/HO-1 signaling axis both in vivo and in vitro. The other metabolite of EZM, ezetimibe glucuronide (EZM-G) had no protective effects against ROS in RIRI. EZM-G also had no antioxidant effects and could not activate Nrf2/HO-1 signal pathway. Our findings also indicated the therapeutic potential of EZM-K in preventing RIRI.
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Ezetimiba , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Transdução de Sinais , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/tratamento farmacológico , Ratos , Transdução de Sinais/efeitos dos fármacos , Ezetimiba/farmacologia , Masculino , Rim/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Linhagem Celular , Heme Oxigenase (Desciclizante)/metabolismoRESUMO
The use of gaseous CO in Pd-catalyzed carbonylative quinolone synthesis presents challenges related to safety and precise pressure control. In response, a streamlined non-gaseous synthesis of 4-quinolone compounds has been developed. This study introduces a tunable CO-releasing system utilizing Fe(CO)5 activated by a dual-base system of piperazine and triethylamine. This alternative liquid CO resource facilitates the palladium-catalyzed carbonylative C-C coupling and subsequent intramolecular cyclization. By tuning the tandem kinetics of carbonylation and cyclization, this non-gaseous method achieves the successful synthesis of 22 distinct 4-quinolones with excellent yields. This is achieved through the three-component condensation of sub-stoichiometric amounts of Fe(CO)5 with 2-iodoaniline and terminal alkynes. Operando mechanistic studies have revealed a novel CO transfer mechanism that facilitates homogeneous carbonylative cyclization, distinguishing this method from traditional techniques. In addition to addressing safety concerns, this approach also provides precise control over selectivity, with significant implications for pharmaceutical research and the efficient synthesis of pharmaceutical and bioactive compounds.
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OBJECTIVE: The objective is to develop a natural and stable anti-oxidative stress and anti-ageing ingredient. In this study, we evaluated the changes in white tea leaves fermented with Eurotium cristatum PLT-PE and Saccharomyces boulardii PLT-HZ and their efficacy against skin oxidative stress. METHODS: We employed untargeted metabolomics technology to analyse the differential metabolites between tea extract (TE) and fermented tea extract (FTE). In vitro, using H2O2-induced HaCaT cells, we evaluated cell vitality, ROS, and inflammatory factors (TNF-α, IL-1ß, and IL-6). Additionally, we verified the effects on the extracellular matrix and nuclear DNA using fibroblasts or reconstructed skin models. We measured skin hydration, elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio in volunteers after using an emulsion containing 3% FTE for 28 and 56 days. RESULTS: Targeted metabolomics analysis of white tea leaves yielded more than 20 differential metabolites with antioxidant and anti-inflammatory activities, including amino acids, polypeptides, quercetin, and liquiritin post-fermentation. FTE, compared to TE, can significantly reduce reactive oxygen species (ROS) and protect against oxidative stress-induced skin damage in H2O2-induced HaCaT cells. FTE can inhibit H2O2-induced collagen degradation by suppressing the MAPK/c-Jun signalling pathway and can also mitigate the reactive oxygen species damage to nuclear DNA. Clinical studies showed that the volunteers' stratum corneum water content, skin elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio significantly improved from the baseline after 28 and 56 days of FTE use. CONCLUSION: This study contributes to the growing body of literature supporting the protective effects against skin oxidative stress and ageing from fermented plant extracts. Moreover, our findings might inspire multidisciplinary efforts to investigate new fermentation techniques that could produce even more potent anti-ageing solutions.
OBJECTIF: L'objectif est de développer un ingrédient naturel et stable contre le stress oxydatif et antiâge. Dans cette étude, nous avons évalué les modifications dans les feuilles de thé blanc fermentées avec la PLTPE Eurotium cristatum et la PLTHZ Saccharomyces boulardii et leur efficacité contre le stress oxydatif cutané. MÉTHODES: Nous avons utilisé une technologie de métabolomique non ciblée pour analyser les métabolites différentiels entre l'extrait de thé (ET) et l'extrait de thé fermenté (ETF). In vitro, à l'aide de cellules HaCaT induites par l'H2O2, nous avons évalué la vitalité cellulaire, les ERO et les facteurs inflammatoires (TNFα, IL1ß, and IL6). Nous avons également vérifié les effets sur la matrice extracellulaire et l'ADN nucléaire à l'aide de fibroblastes ou de modèles cutanés reconstruits. Nous avons mesuré l'hydratation de la peau, l'élasticité, la surface de rides, le rapport des surfaces de rides, la surface d'érythème, et le rapport des surfaces d'érythème chez des volontaires ayant utilisé une émulsion contenant 3% d'ETF pendant 28 et 56 jours. RÉSULTATS: L'analyse métabolomique ciblée des feuilles de thé blanc a révélé plus de 20 métabolites différentiels ayant des activités antioxydantes et antiinflammatoires, notamment des acides aminés, des polypeptides, de la quercétine et de la liquiritine après fermentation. Par rapport à l'ET, l'ETF peut réduire significativement les espèces réactives de l'oxygène (ERO) et protéger contre les lésions cutanées induites par le stress oxydatif dans les cellules HaCaT induites par l'H2O2. L'ETF peut inhiber la dégradation du collagène induite par l'H2O2 en supprimant la voie de signalization MAPK/cJun et peut également atténuer les dommages causés par les espèces réactives de l'oxygène à l'ADN nucléaire. Les études cliniques ont montré que la teneur en eau de la couche cornée des volontaires, l'élasticité de la peau, la surface de rides, le rapport des surfaces de rides, la surface d'érythème et le rapport des surfaces d'érythème se sont significativement améliorés par rapport à la référence après 28 et 56 jours d'utilisation d'ETF. CONCLUSION: Cette étude contribue au corpus croissant de littérature soutenant les effets protecteurs des extraits de plantes fermentées contre le stress oxydatif cutané et le vieillissement. En outre, nos résultats pourraient inspirer des efforts pluridisciplinaires pour étudier de nouvelles techniques de fermentation susceptibles de produire des solutions antiâge encore plus puissantes.
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Malignant adenomyoepithelioma(MAME)of the breast is a rare tumor with an incidence less than 1% of primary breast cancer.The low incidence and diverse histomorphology pose challenges to the accurate diagnosis and clinical management of MAME.This paper reports a case of MAME of the breast with an intraductal papillary growth pattern and summarizes the clinical features,pathological features,diagnosis,treatment,and prognosis of MAME of the breast in the last 5 years.
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Adenomioepitelioma , Neoplasias da Mama , Humanos , Adenomioepitelioma/patologia , Feminino , Neoplasias da Mama/patologia , Pessoa de Meia-IdadeRESUMO
This study aimed to systematically evaluate the effectiveness and safety of Tanreqing Injection in the treatment of severe pneumonia in the elderly. Eighteen randomized controlled trials(RCTs) involving 1 457 elderly patients with severe pneumonia were included in the study after conducting searches in both Chinese and English databases as well as clinical trial registration platforms. The quality of the included studies was assessed using the Cochrane risk of bias assessment tool. Meta-analysis were conducted using RevMan 5.4 and Stata 17 software, and trial sequential analysis(TSA) was performed using TSA 0.9.5.10 beta software. Meta-analysis results showed that compared with conventional western medicine treatment, Tanreqing Injection + conventional western medical significantly improved the clinical effectiveness in elderly patients with severe pneumonia(RR=1.26, 95%CI[1.20, 1.32], P<0.000 01), arterial oxygen partial pressure(SMD=6.23, 95%CI[3.29, 9.18], P<0.000 1), oxygenation index(SMD=11.72, 95%CI[4.41, 19.04], P=0.002), reduce procalcitonin(SMD=-6.16, 95%CI[-8.10,-4.21], P<0.000 01), C-reactive protein(SMD=-8.50, 95%CI[-11.05,-5.96], P<0.000 01), white blood cell count(SMD=-4.56, 95%CI[-5.73,-3.39], P<0.000 01), and shortened the duration of fever(SMD=-3.12, 95%CI[-4.61,-1.63], P<0.000 1), cough(SMD=-4.84, 95%CI[-6.90,-2.79], P<0.000 01), lung rales(SMD=-0.99, 95%CI[-1.54,-0.44], P=0.000 4), and mechanical ventilation time(SMD=-3.26, 95%CI[-5.03,-1.50], P=0.000 3), increase CD4~+ T-cell levels(SMD=6.73, 95%CI[5.23, 8.23], P<0.000 01) and CD8~+ T-cell levels(SMD=7.47, 95% CI[5.32, 9.61], P<0.000 01) with no significant adverse reactions. TSA confirmed the stability and reliability of the results related to clinical effectiveness. This study suggests that Tanreqing Injection, as a Chinese medicinal preparation, has a significant therapeutic effect and good safety profile in the treatment of severe pneumonia in elderly patients. Due to the limited quality of the included studies, high-quality RCT is still needed to provide evidence support for the above conclusions.
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Medicamentos de Ervas Chinesas , Pneumonia , Idoso , Humanos , Tosse/induzido quimicamente , Medicamentos de Ervas Chinesas/efeitos adversos , Pneumonia/tratamento farmacológico , Reprodutibilidade dos Testes , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Background: Lymphoepithelioma-like carcinoma of the liver is a rare primary malignancy of the liver. The identification of lymphoepithelioma-like cholangiocarcinoma is very limited as there are currently very few reports of such cases. Although previous studies have reported the lymphoepithelioma-like cholangiocarcinoma pathologic features, few studies have revealed the clinic features, imaging characteristics, and clinical course and outcomes. This study was analyzed from multiple aspects such as contrast-enhanced ultrasound, magnetic resonance imaging, and pathological characteristics, aiming to improve the comprehensive understanding of this rare subtype of disease. Case Presentation: A 43-year-old female with a history of hepatitis B for over 20 years presented with a lesion found in the right lobe of her liver. After discussion by a multidisciplinary team (MDT), malignant tumors cannot be excluded based on contrast-enhanced ultrasound and MRI. Thus, we decided to perform surgery for the patient. Postoperative pathology confirmed lymphoepithelioma-like intrahepatic cholangiocarcinoma. After 3 months of follow-up, the patient was still alive and no recurrence was observed. Conclusion: The purpose of this article is to describe a rare case of lymphoepithelioma-like intrahepatic cholangiocarcinoma and analyze its contrast-enhanced ultrasound and contrast-enhanced MRI features, which will be helpful for physicians in diagnosing this disease. From the perspective of CEUS, the wedge-shaped highly enhanced area around the lesion in the arterial phase appears to be inflammatory but looks malignant based on the extremely fast washout. The lesion showed a low signal on T1WI, a high signal on T2WI and DWI, and an abnormal perfusion shadow can be seen behind the lesion. In particular, this subtype of cholangiocarcinoma has a good prognosis, the clinician should improve the recognition of the disease to strive for early diagnosis and therapy.
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The role of noncovalent bonding, including multiatomic interactions (van der Waals-like forces) and ionic characteristics, in the intermetallic clathrate A x Si136 (A = Na, K, Rb; 0 < x ≤ 24) is qualitatively discussed. Using the local density approximation (LDA) to density functional theory (DFT), we investigated the effect of different guest filling and pressure parameters on the structural and electronic properties of these materials. In the context of the rigid-band model, we first noted that the competition between van der Waals-like multiatomic interactions and ionicity due to the extent of charge transfer responsible for guest-framework complexes accounts for the nonmonotonic structural response upon guest filling in A x Si136 (0 ≤ x ≤ 8), which is in good agreement with previous experimental findings as well as theoretical predictions. In comparison with computational work initiated under zero temperature and pressure conditions, the DFT calculations at high pressure (P = 3 GPa) show no apparent variation with respect to the electronic structure. Regarding the A16Si136 compound, the encapsulated sodium atoms residing in the 20-atom cage cavity act as centers of somewhat localized electrons compared with the alkaline metal sites inside Si28 cage voids. Moreover, the substitution of heavier guest atoms (e.g., Rb) for all the Na atoms in Na8Si136 yields less significant charge transfer between the guest and framework constituents. The net effect of quickly increasing multiatomic interactions and slowly decreasing ionic bonding between the encapsulated atom and Si28 cage may prevent the entire lattice configuration from contracting in a more rapid way when guest species are tuned from Na to Rb in A x Si136 (A = Na, Rb; 0 < x ≤ 8) with increased composition x. In other words, the coulombic attraction due to ionic bonding slightly outweighs the repulsive interaction between the Rb atom and Si28 cage. In addition, the determined formation energy per conventional unit cell in K8Si136, Rb8Si136 and Na12Si136 attains a minimum value, demonstrating the stabilizing effect of guests incorporated into "oversized" cage cavities.
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The educational burden from extracurricular tutoring class has become a pressing social issue in China. This study used data from the China family panel studies (CFPS) in 2014, 2016, and 2018 to empirically analyze the impact of Internet usage on children's participation in extracurricular tutoring class. There are many factors that influence parents' decisions to enroll their children in extracurricular tutoring class. These factors include family income status, the level of importance parents place on their children's education, the marginal returns on educational investment, academic pressure, etc. However, in today's digitalized society, the widespread use of the internet will also become an important influencing factor in parents' decisions regarding educational investment. The study finds that, parents by using the Internet significantly increase the probability of enrolling their children in extracurricular tutoring class. Through mechanism regression analysis, it is concluded that internet usage has a positive influence on parents enrolling their children in extracurricular tutoring class by increasing the frequency of social interaction and raising parents' educational expectations for their children. Based on the empirical results, the following policy suggestions were proposed: 1. Schools should establish a more comprehensive after-school education service system to improve the engagement of students in compulsory education; 2. The government can enhance the accessibility and optimization of educational resources by increasing investment in education, improving the quality of in-school education, and optimizing the management and supervision of extracurricular tutoring class. This ensures that students can access high-quality educational services.
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Uso da Internet , Pais , Estudantes , Humanos , Criança , China , Masculino , Feminino , Uso da Internet/estatística & dados numéricos , Instituições Acadêmicas , Adulto , Adolescente , Internet/estatística & dados numéricosRESUMO
To better understand the secret of natural flying vertebrates such as how humming-birds twist their wings to achieve superb flight ability, we presented a numerical investigation of dynamic twisting based on a hummingbird-like flapping wing model. Computational fluid dynamic simulations were performed to examine the effects of dynamic twisting on the unsteady flow field, the generation of instantaneous aerodynamic forces, and the time-averaged aerodynamic performance. This research reveals the details of leading-edge vortices (LEVs) and the underlying mechanisms behind the positive effects of wing torsion. The results demonstrated that wing torsion can effectively maintain the favorable distribution of effective angle of attack along the wing spanwise, resulting in a higher time-averaged thrust and vertical force. Further, the proper parameters of dynamic twisting can also improve the propulsive efficiency in forward flight. Dynamic twisting also showed a superior ability in controlling the airflow separation over the wing surface and maintaining the stability of the LEV. The amplitudes of effective angle of attack associated with the highest peak thrust and the maximum thrust-to-power at different advanced ratios were also explored, and it was found that the amplitudes decrease with increasing advanced ratio. To improve the efficiency during larger advanced ratio, specific modifications to the pitching of the wing were proposed in this work. The research in this paper has promising implications for the bio-inspired flapping wing.
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Voo Animal , Modelos Biológicos , Animais , Fenômenos Biomecânicos , Fenômenos Mecânicos , Asas de Animais , AvesRESUMO
Bladder cancer (BC), a highly prevalent malignancy of the urinary system, necessitates further investigation into its progression mechanisms. N6-methyladenosine (m6A) RNA methylation, a prevalent modification in cellular RNA, has been implicated in the tumorigenesis and metastasis of various cancers. In this study, the upregulation of FTO in human BC samples and its association with poor prognosis were demonstrated using immunohistochemistry (IHC) on tissue sections collected from BC patients. The functional role of FTO in promoting the proliferation and metastasis abilities of BC cells was determined using a combination of in vitro and in vivo assays. In vitro, we conducted cell proliferation assays, such as the Cell Counting Kit-8 (CCK-8) assay, and metastasis assays, including the wound healing assay and transwell invasion assay. In vivo, we employed xenograft models to assess tumor growth and metastasis. Furthermore, our investigation into potential FTO targets in BC cells revealed that FTO modifies PTPN6 mRNA, leading to increased stability and expression of PTPN6, thereby enhancing proliferation and metastasis abilities. In conclusion, our findings indicate that FTO serves as an oncogenic factor in BC, suggesting its potential utility as a diagnostic or prognostic biomarker for bladder cancer.
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Ischemia-reperfusion injury (IRI) is a significant contributor to acute kidney injury (AKI) and is associated with substantial morbidity and mortality rates. In this study, we aimed to investigate the role of NAT10 and its ac4C RNA modification in IRI-induced renal injury. Our findings revealed that both the expression level of NAT10 and the RNA ac4C level in the kidneys were elevated in the IRI group compared to the sham group. Functionally, we observed that inhibition of NAT10 activity with Remodelin or the specific knockout of NAT10 in the kidney led to a significant attenuation of IRI-induced renal injury. Furthermore, in vitro experiments demonstrated that NAT10 inhibition and specific knockout of NAT10 in the kidney markedly suppressed global ac4C RNA modification, providing protection against hypoxia/reoxygenation-induced tubular epithelial cell injury and ferroptosis. Mechanistically, our study uncovered that NAT10 promoted ac4C RNA modification of NCOA4 mRNA, thereby enhancing its stability and contributing to IRI-induced ferroptosis in tubular epithelial cells (TECs). These findings underscore the potential of NAT10 and ac4C RNA modification as promising therapeutic targets for the treatment of AKI. Overall, our study sheds light on the critical involvement of NAT10 and ac4C RNA modification in the pathogenesis of IRI-induced renal injury, offering valuable insights for the development of novel AKI treatment strategies.