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Here we present a highly enantioselective [2π + 2σ] photocycloaddition of bicyclo[1.1.0]butanes (BCBs). The reaction uses a variety of vinylazaarenes as partners and is catalyzed by a polycyclic aromatic hydrocarbon (PAH)-containing chiral phosphoric acid as a bifunctional chiral photosensitizer. A wide array of pharmaceutically important bicyclo[2.1.1]hexane (BCH) derivatives have been synthesized with high yields, enantioselectivity, and diastereoselectivity. In addition to the diverse 1-ketocarbonyl-3-substituted BCBs, α/ß-substituted vinylazaarenes are compatible with such an unprecedented photoredox catalytic pathway, resulting in the successful assembly of an all-carbon quaternary stereocenter or two adjacent tertiary stereocenters on the product.
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While photochemical deracemization significantly enhances atom economy by eliminating the necessity for additional oxidants or reductants, the laborious presynthesis of substrates from feedstock chemicals is often required, thereby compromising the practicality of this method. In this study, we propose a novel approach known as de novo deracemization synthesis, which involves direct utilization of simple substrates undergoing both photochemical transformation and reversible photochemical transformation. The efficient enantiocontrol of chiral catalysts in the latter process establishes an effective platform for deracemization. This alternative and practical approach to address the challenges of asymmetric photocatalysis has been successfully demonstrated in the photosensitized de novo deracemization synthesis of azaarene-functionalized cyclobutanes featuring three stereocenters, including an all-carbon quaternary center. By exclusively employing a suitable chiral catalyst to enable kinetically controlled [2 + 2] photocycloreversion, we pave a creative path toward achieving more cost-effective photochemical deracemization.
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Although electroacupuncture (EA) stimulation is a widely used therapy for chronic pain and comorbid psychiatric disorders, its long-term effects on chronic neuropathic pain-induced depression and the underlying mechanisms remain elusive. In the present study, we found that EA stimulation was able to restore adult neurogenesis in the ventral dentate gyrus (DG), by both increasing neuronal differentiation and restoring the normal morphology of newborn dendrites, in mice with spared nerve injury surgery. By ablating the Nestin+ neural stem cells (NSCs) via diphtheria toxin fragment A expression, we further proved that neurogenesis in the ventral DG was crucial to the long-term, but not the immediate antidepressant effect of EA, nor was it associated with nociception. Furthermore, we found that the restoration of neurogenesis was dependent on Tet1-mediated epigenetic modification upon EA treatment. Tet1 could bind to the promoter of the Prox1 gene, thus catalyzing its demethylation and facilitating its expression, which finally contributed to the restoration of neurogenesis and amelioration of depression-like behaviors induced by chronic neuropathic pain. Thus, we conclude that EA stimulation restores inhibited Tet1 expression in hippocampal NSCs of mice with chronic neuropathic pain, and increased Tet1 expression ameliorates hypermethylation of Prox1 and restores normal adult neurogenesis in the ventral DG, which contributes to the long-term antidepressant effect of EA.
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Eletroacupuntura , Neuralgia , Camundongos , Animais , Depressão/complicações , Depressão/terapia , Neurogênese , Hipocampo/metabolismo , Neuralgia/terapia , Neuralgia/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismoRESUMO
Hydroxylation of aryl sulfonium salts could be realized by utilizing acetohydroxamic acid and oxime as hydroxylative agents in the presence of cesium carbonate as a base, leading to a variety of structurally diverse hydroxylated arenes in 47-95% yields. In addition, the reaction exhibited broad functionality tolerance, and a range of important functional groups (e.g., cyano, nitro, sulfonyl, formyl, keto, and ester) could be well amenable to the mild reaction conditions.
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In this work, we introduce a novel multimode fiber (MMF) - seven core fiber (SCF) - MMF (MCM) optical fiber biosensor, also known as the WaveFlex biosensor (plasma wave assisted fiber biosensor), based on localized surface plasmon resonance (LSPR) for qualitative detection of xanthine. Xanthine is a purine base widely distributed in human blood and tissues, and commonly used as an indicator for various disease detections. The MCM sensor incorporates a tapered optical fiber structure, fabricated using the combiner manufacturing system (CMS), and is designed with SCF and MMF. By effectively harnessing LSPR, the sensor boosts the attachment points of biomolecules on the probe surface through immobilized tungsten disulfide (WS2)-thin layers, gold nanoparticles (AuNPs), and carbon nitride quantum dots (C3N-QDs). The functionalization of xanthine oxidase (XO) on the sensing probe further enhances the sensor's specificity. The proposed WaveFlex biosensor exhibits a remarkable sensitivity of 3.2â nm/mM and a low detection limit of 96.75 µM within the linear detection range of 100 - 900 µM. Moreover, the sensor probe demonstrates excellent reusability, reproducibility, stability, and selectivity. With its sensitivity, biocompatibility, and immense potential for detecting human serum and fish products, this WaveFlex biosensor presents a promising platform for future applications.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Animais , Humanos , Ouro/química , Xantina , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química , Ressonância de Plasmônio de SuperfícieRESUMO
In this work, the one-dimensional (1D) Ni-Co-Se nanowire arrays with rich grain-boundaries were prepared through the solvothermal method and gas-phase selenizaiton. The results showed that the structure and crystallization of the Ni-Co-Se nanowire arrays could be modulated through the optimization of selenizaiton time. The optimal Ni-Co-Se electrode sample displayed an area specific capacitance of 242.6µAh cm-2at 30 mA cm-2with a current retention rate of 68.34%. The assembled Ni-Co-Se/Active carbon (AC) electrode-based asymmetric supercapacitor (ASC) showed the area specific capacitances of 329.2µAh cm-2and 225.8µAh cm-2at 3 mA cm-2and 30 mA cm-2, respectively. A 73.33% retention rate of capacitance was observed after 8000 charge/discharge cycles. Besides, the further fabricated all-solid ASC delivered the power densities of 342.94 W kg-1and 3441.33 W kg-1at the energy densities of 37.62 Wh kg-1and 25.81 Wh kg-1, respectively. Those results suggested the potentials of the obtained Ni-Co-Se nanowire arrays as electrode material for the high-performance pseudocapacitors.
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Traditional thermochromic photonic crystal (PC) usually has a slow and reversible thermal response, which limits its application in thermal printing. Here, the authors develop a thermochromic "SiO2 -PC/PEG" double layer structure with a responding time of milliseconds for fast thermal printing. Controlled by the print-head, the polyethylene glycol (PEG) melts, infiltrates, and solidifies within the interparticle voids, which instantly and irreversibly changes the refractive index and produces the PC pattern. Multicolor printing can be realized by tuning the size and type of colloidal particles. Resolution as high as 300 DPI is achieved to print the high-resolution patterns and then the grayscale patterns based on the control of pixel densities. Different from fiber thermal paper, the "SiO2 -PC/PEG" film has no toxic bisphenol A and possesses superior light stability for keeping the images longer. It is fully compatible with the commercial printer, which provides a mature solution for fast and convenient preparation of PC patterns.
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Polietilenoglicóis , Dióxido de Silício , Óptica e Fotônica , Fótons , Impressão TridimensionalRESUMO
OBJECTIVES: To explore the efficacy of microwave ablation (MWA) in the treatment of benign thyroid nodules, and analyze related influencing factors. METHODS: The clinical and ultrasound data of 115 patients with 115 benign thyroid nodules treated with MWA were retrospectively analyzed. The volume of nodules at 1, 3, 6, and 12 months after the procedure was obtained, and the volume reduction rate (VRR) at each time point was calculated. With VRR > 90% as the criterion for nodule cure, binary logistic regression was employed to screen the factors that affect the efficacy. RESULTS: â At 1, 3, 6, and 12 months after the procedure, the volume of nodules continued to decrease, the VRR gradually increased, and the differences at each time point were statistically significant (p < 0.05). A total of 29 (25.21%) nodules disappeared completely at 12 months after the procedure; â¡ Multivariate stepwise logistic regression showed that there was a statistically significant difference for the internal component of nodules, enhancement mode, and immediate volume after the procedure in determining the ablation efficacy (p < 0.05); ⢠The ROC curve was plotted for predicting the efficacy of MWA, with the results showing that the AUC, sensitivity, specificity, and accuracy were 0.82, 67.50, 88.00, 79.10%, respectively; ⣠11 cases (9.56%) had side effects, 10 cases (8.70%) had minor complications, and three cases (2.61%) had major complications. CONCLUSION: MWA is safe and effective in the treatment of benign thyroid nodules. The internal component of nodules, enhancement mode, and immediate volume after the procedure are independent factors that affect the efficacy of ablation.
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Ablação por Radiofrequência , Nódulo da Glândula Tireoide , Humanos , Micro-Ondas , Estudos Retrospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Resultado do TratamentoRESUMO
Nitrogen adsorption-desorption for mesopore characterization requires the using of expensive instrumentation, time-consuming processes, and the consumption of liquid nitrogen. Herein, a new method is developed to measure the pore parameters through mixing a mesoporous substance with a supersaturated SiO2 colloidal solution at different temperatures, and subsequent rapid measurement of reflection changes of the precipitated liquid photonic crystals. The pore volumes and diameters of mesoporous silica were measured according to the positive correlation between unit mass reflection change (Δλ/m) and pore volume (V), and the negative correlation between average absorption temperature (T) and pore diameter (D). This new approach may provide an alternative method for fast, convenient and economical characterization of mesoporous materials.
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A test-paper-like photonic crystal (PC) viscometer is fabricated based on the positive correlation between viscosity and the infiltration time for viscous liquid to entirely soak the PC film. It can be broadly used in different occasions to quickly determine the viscosity for many liquids, considering its portable and disposable characteristics and the requirement of little samples.
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Introduction: The recognition of culture and context as pivotal influences on the developmental trajectory of young children has been underscored by numerous developmental theories. Localized knowledge is essential for comprehending cultural universality with specificity for early childhood development (ECD). Methods: Thirteen focus group discussions were conducted with professionals, caregivers, and teachers from four regions in China. Thematic content analysis was employed to identify patterns and themes, followed by coding to identify more conceptual units of meaning. Results: The findings reveal distinct culture-based skills across four domains of ECD in China. These highlight a local culture that embraces a comprehensive, dynamic, and staged perspective on the development of young children. This study elucidates the multidimensional impact of the environment on young children's development, with a focus on children's behavioral characteristics and temperament traits, ECEC practices, and ECEC beliefs that transcend identity, culture, and the economy. Discussion: This study contributes to the assessment of ECD for future cultural comparisons and enhances the scientific understanding of the interplay between developmental skills in young children and diverse cultural expectations and backgrounds.
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Multi-layered plasmonic nanostructures are able to highly promote the near-field confinement and effectively activate analytes, which are of predominate significance but are extremely challenging. Herein, the semi-open Au core@carved AuAg multi-shell superstructure nanoparticles (multi-Au@Ag-Au NPs, multi = mono, bi, tri, tetra, and penta) are reported with a high designability on electromagnetic field and capability of effectively capturing analytes. By controlling synthetic parameters such as the number of galvanic exchange and Ag growth, multi-Au@Ag-Au NPs are successfully obtained, with tunable layer numbers and asymmetric nanoholes. Due to collective plasmon oscillations of multi-layered built-in nanogaps, the electromagnetic field strength of a single penta-Au@Ag-Au entity reach 48841. More importantly, the penta-Au@Ag-Au NPs show a remarkable light-harvesting capability, which is adaptive to different Raman lasers, supporting high-diversity detection. Additionally, the structural specificity allows analytes to be sufficiently captured into interior hotspots, and further achieve highly sensitive detection with limit of detection down to 3.22 × 10-12 M. This study not only provides an effective pathway for integrating abundant hotspots and activating target molecules in single plasmonic superstructure, but stimulates advancements in SERS substrates for various applications.
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We report here a step-economic and cost-effective cross-electrophile coupling of aryl thianthrenium salts with widely available aryl bromides, which proceeded effectively via C-S bond activation at ambient temperature in THF in the presence of a palladium catalyst, magnesium turnings, and lithium chloride to enable the facile assembly of a wide array of structurally diverse biaryls in modest to good yields with good functional group compatibility. In addition, the gram-scale reaction could also be realized.
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Significance: This study innovates by systematically integrating the molecular mechanisms of iron death and its application in cancer therapy. By deeply analyzing the interaction between iron death and the tumor microenvironment, the study provides a new theoretical basis for cancer treatment and directions for developing more effective treatment strategies. In addition, the study points to critical issues and barriers that need to be addressed in future research, providing valuable insights into the use of iron death in clinical translation. Recent Advances: These findings are expected to drive further advances in cancer treatment, bringing patients more treatment options and hope. Through this paper, we see the great potential of iron death in cancer treatment and look forward to more research results being translated into clinical applications in the future to contribute to the fight against cancer. Critical Issues: In today's society, cancer is still one of the major diseases threatening human health. Despite advances in existing treatments, cancer recurrence and drug resistance remain a severe problem. These problems increase the difficulty of treatment and bring a substantial physical and mental burden to patients. Therefore, finding new treatment strategies to overcome these challenges has become significant. Future Directions: The study delved into the molecular basis of iron death in tumor biology. It proposed a conceptual framework to account for the interaction of iron death with the tumor immune microenvironment, guide treatment selection, predict efficacy, explore combination therapies, and identify new therapeutic targets to overcome cancer resistance to standard treatments, peeving a path for future research and clinical translation of ferroptosis as a potential strategy in cancer therapy. Antioxid. Redox Signal. 41, 616-636. [Figure: see text].
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Ferroptose , Neoplasias , Microambiente Tumoral , Ferroptose/efeitos dos fármacos , Humanos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/terapia , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Animais , Ferro/metabolismoRESUMO
Cancer of unknown primary (CUP) site poses diagnostic challenges due to its elusive nature. Many cases of CUP manifest as pleural and peritoneal serous effusions. Leveraging cytological images from 57,220 cases at four tertiary hospitals, we developed a deep-learning method for tumor origin differentiation using cytological histology (TORCH) that can identify malignancy and predict tumor origin in both hydrothorax and ascites. We examined its performance on three internal (n = 12,799) and two external (n = 14,538) testing sets. In both internal and external testing sets, TORCH achieved area under the receiver operating curve values ranging from 0.953 to 0.991 for cancer diagnosis and 0.953 to 0.979 for tumor origin localization. TORCH accurately predicted primary tumor origins, with a top-1 accuracy of 82.6% and top-3 accuracy of 98.9%. Compared with results derived from pathologists, TORCH showed better prediction efficacy (1.677 versus 1.265, P < 0.001), enhancing junior pathologists' diagnostic scores significantly (1.326 versus 1.101, P < 0.001). Patients with CUP whose initial treatment protocol was concordant with TORCH-predicted origins had better overall survival than those who were administrated discordant treatment (27 versus 17 months, P = 0.006). Our study underscores the potential of TORCH as a valuable ancillary tool in clinical practice, although further validation in randomized trials is warranted.
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Aprendizado Profundo , Neoplasias Primárias Desconhecidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ascite/patologia , Citodiagnóstico/métodos , Neoplasias Primárias Desconhecidas/patologia , Curva ROCRESUMO
Due to their low cost and excellent electrocatalytic performance, nickel-based hydroxides are widely used as hydrogen evolution catalysts for large-scale hydrogen production by water electrolysis. In this study, a heterostructured composite with improved electron transport and modulated electron surface density was prepared by combining Ni(OH)2 with two-dimensional layered Ti3C2Tx (Ti3C2Tx-MXene). Ni(OH)2 nanosheets were formed on nickel foam (NF) substrates using acid etching, followed by the longitudinal growth of negatively charged Ti3C2Tx-MXene on positively charged Ni(OH)2/NF via electrophoretic deposition. The resulting structure facilitates spontaneous electron transfer from Ti3C2Tx-MXene to Ni(OH)2/NF by means of the Mott-Schottky heterostructure effect and establishes a continuous electron transport path which effectively increases the concentration of active sites, improving hydrogen evolution during water electrolysis. The obtained electrode is characterized by an HER overpotential of 66 mV (vs. RHE) and a Tafel slope of +105 mV dec-1 at a current density of 10 mA cm-2, combined with good electrochemical stability.
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Cell's activities are highly dependent on signal molecules, of which reactive oxygen species of the superoxide anion (O2â¢-) and hydrogen peroxide (H2O2) are important ones that always work together to regulate biological processes such as apoptosis and oxidative stress. It is of significance to realize simultaneous qualification of O2â¢- and H2O2 but it still faces challenges particularly in live-cell assay with a complex environment. We report the design of a bifunctional sensing material by interfacially regulating ZIF-67 on bacteria Shewanella putrefaciens to generate cobalt nanoparticles/nitrogen-doped porous carbon nanorods (Co/N-doped CNRs) and its sensing chip for qualifying cell-released O2â¢- and H2O2. Co/N-doped CNRs exhibit unique properties including porous structure for significantly increased reaction surface area and coordinating Co nanoparticles for rich active sites. The bifunctional Co/N-doped CNRs is used to fabricate the electrochemical sensing chip, which achieves a fast response time (0.5 s for O2â¢-, 1.9 s for H2O2), a low detection limit (0.69 nM for O2â¢-, 2.25 µM for H2O2), and a remarkably high sensitivity (792.30 µA·µM-1·cm-2 for O2â¢-, 153.91 µA·mM-1·cm-2 for H2O2), among the best of reported bifunctional nanozymes.
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Peróxido de Hidrogênio , Nanopartículas Metálicas , Espécies Reativas de Oxigênio , Técnicas Eletroquímicas , Superóxidos , Nanopartículas Metálicas/químicaRESUMO
Hydrogen sulfide (H2S) has comprehensive contributions to maintaining the normal operation and stability of organisms, and it also occurs in the wastewater environment and is related to the deterioration of foodstuffs. Therefore, developing high-sensitive detection techniques for tracing H2S is promising and meaningful. Inspired by this, a novel nopinone-based fluorescent probe NPS for the recognition of H2S was designed and synthesized with excellent sensitivity, low limit of detection (79 nM), good selectivity, and wide pH range (5-9). NPS could emit strong yellow fluorescence and its emission intensity showed a remarkable augmentation at 520 nm upon the supplement of H2S. Furthermore, the recognition mechanism of NPS for H2S was verified by the HRMS analysis, 1H NMR spectra titration, and DFT computation. What is more, NPS also had broad applications in the monitoring of real water samples, red wine, beer, and eggs samples, which showed its development prospect and value in environmental pollution, foodstuffs quality analysis fields. NPS also was applied to monitor trace exogenous H2S and bioimaging in living cells and zebrafish.
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Corantes Fluorescentes , Sulfeto de Hidrogênio , Humanos , Animais , Corantes Fluorescentes/química , Peixe-Zebra , Células HeLa , Esqueleto/química , Sulfeto de Hidrogênio/química , ÁguaRESUMO
Currently, information on microplastics (MPs) weathering characteristics and ecological functions driven by MPs-associated microbes in mangrove ecosystems remains unclear, especially in the degraded areas. Herein, we compared the weathering characteristics of MPs in both undegraded and degraded mangrove sediments, and then explored the potential interactions between their weathering characteristics and microbially-driven functions. After 70 days of incubation, different MPs (including polyethylene PE, polystyrene PS, and polylactic acid PLA) were strongly weathered in mangrove sediments, with significant erosion features. Interestingly, more obvious weathering characteristics were found for MPs in the undegraded mangrove sediments. O/C ratio value of MPs in the undegraded sediments was 2.3-3.0 times greater than that in the degraded ones. Besides, mangrove degradation reduced network complexity among MPs-associated microorganisms and affected their metabolic activities. Bacteria involved in carbon cycle process enriched on nondegradable MPs, whereas abundant bacteria responsible for sulphur cycle were observed on PLA-MPs. Moreover, these relevant bacteria were more abundant on MPs in the undegraded mangrove sediments. Mangrove degradation could directly and indirectly affect MPs weathering process and microbially-driven functions through regulating sediment properties and MPs-associated microbes. During weathering, contact angle and roughness of MPs were key factors influencing the colonisation of hydrocarbon degradation bacteria on MPs.
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Microplásticos , Poluentes Químicos da Água , Plásticos , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Poliésteres , Bactérias , Sedimentos GeológicosRESUMO
Electrically responsive photonic crystals are promising materials for electrophoretic color displays with better brightness and color saturation. However, electric field must always be applied to maintain the specific colors, which brings concerns about the power consumption and signal stability and reversibility. Here, we show an electrically responsive photonic crystal with two stable states at 0 V, which are the colored state or the colorless state with ordered or disordered particle arrangement. The color state can be reversibly switched by applying a short-time electrical field, just like in the case of commercial electrophoretic ink. With optimized recipe and electric field, the photonic crystals encapsulated in the prototype display panel are proved to have potentials in high resolution, multi-color, and greyscale display, which lays down a firm basis for reflective displays with low power consumption and good visibility.