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1.
Food Chem ; 462: 140986, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208737

RESUMO

Harvest season exerts great influence on tea quality. Herein, the variations in non-volatile flavor substances in spring and summer fresh tea leaves of four varieties were comprehensively investigated by integrating UHPLC-Q-Exactive based lipidomics and metabolomics. A total of 327 lipids and 99 metabolites were detected, among which, 221 and 58 molecules were significantly differential. The molecular species of phospholipids, glycolipids and acylglycerolipids showed most prominent and structure-dependent seasonal changes, relating to polar head, unsaturation and total acyl length. Particularly, spring tea contained higher amount in aroma precursors of highly unsaturated glycolipids and phosphatidic acids. The contents of umami-enhancing amino acids and phenolic acids, e.g., theanine, theogallin and gallotannins, were increased in spring. Besides, catechins, theaflavins, theasinensins and flavone/flavonol glycosides showed diverse changes. These phytochemical differences covered key aroma precursors, tastants and colorants, and may confer superior flavor of black tea processed using spring leaves, which was verified by sensory evaluation.


Assuntos
Camellia sinensis , Aromatizantes , Lipidômica , Espectrometria de Massas , Metabolômica , Folhas de Planta , Estações do Ano , Camellia sinensis/química , Camellia sinensis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Cromatografia Líquida de Alta Pressão , Aromatizantes/química , Aromatizantes/metabolismo , Humanos , Paladar , Odorantes/análise , Lipídeos/análise , Lipídeos/química
2.
J Mater Chem B ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445792

RESUMO

Owing to their inherent flexibility and excellent biocompatibility, liquid metals (LMs) have been explored at the frontiers of clinical therapy. Herein, a LM and tanshinone IIA (TA) drugs were dispersed into sodium alginate (SA) solution by ultrasonication to prepare SA/LM/TA, which is an injectable biomaterial for stable drug release and intrapericardial injection for the treatment of myocardial infarction (MI). The SA/LM/TA has a low viscosity and can be injected smoothly using a syringe. In rat models of MI, we demonstrated that SA/LM/TA injection in the pericardial cavity is a biosafe and effective method to deliver a carrier containing LM particles and TA drugs for MI treatment. After injection, the drug release is slow and stable in the pericardial cavity, increasing the cardiac retention of drugs. After surgery and treatment for 7 days, the cardiac function of rats improved compared with the control group and the TA direct injection group. The intrapericardial injection of SA/LM/TA improves cardiac functions and mitigates cardiac remodeling post myocardial infarction of rats. Overall, the present study establishes a therapeutic strategy for treatment of myocardial infarction by intrapericardial injection of SA/LM/TA and expands the application categories of LM biomaterials in disease treatments.

3.
Small Methods ; : e2401103, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39436055

RESUMO

The construction of highly efficient and self-supported electrocatalysts with abundant active sites for pH-universal hydrogen evolution reaction (HER) and alkaline water splitting is significantly challenging. Herein, Co and MoC nanoparticles embedded in nitrogen-doped carbon nanofibers (Co-MoC/NCNFs) which display a bamboo-like morphology are prepared by electrospinning followed by the carbonization method. The electrospun MoC possesses an ultrasmall size (≈5 nm) which can provide more active sites during electrocatalysis, while the introduction of Co greatly optimizes the electronic structure of MoC. Both endow the Co-MoC/NCNFs with superior HER performances over a wide pH range, with low overpotentials of 86, 116, and 145 mV to achieve a current density of 10 mA cm-2 in alkaline, acidic, and neutral media, respectively. Additionally, the catalyst exhibits remarkable alkaline oxygen evolution reaction (OER) activity with an overpotential of 254 mV to reach 10 mA cm-2. Density functional theory calculations confirm that electron transfer from Co to MoC regulates the adsorption free energy for hydrogen, thereby promoting HER. Moreover, an electrolyzer assembled with Co-MoC/NCNFs requires only a cell voltage of 1.59 V at 10 mA cm-2 in 1 m KOH. This work opens new pathways for the design of high-efficiency electrocatalysts for energy conversion applications.

4.
bioRxiv ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39372771

RESUMO

Voltage-gated K+ channels play central roles in human physiology, both in health and disease. A repertoire of inhibitors that are both potent and specific would therefore be of great value, not only as pharmacological agents but also as research tools. The small molecule RY785 has been described as particularly promising in this regard, as it selectively inhibits channels in the Kv2 subfamily with high potency. Kv2 channels are expressed in multiple cell types in humans, and are of particular importance for neuronal function. The mechanism of action of RY785 has not yet been determined at the molecular level, but functional studies indicate it differs from that of less specific inhibitors, such as quaternary-ammonium compounds or aminopyridines; RY785 is distinct also in that it is electroneutral. To examine this mechanism at the single-molecule level, we have carried out a series of all-atom molecular dynamics simulations based on the experimental structure of the Kv2.1 channel in the activated, open state. First, we report a 25-microsecond trajectory calculated in the absence of any inhibitor, under an applied voltage of 100 mV, which demonstrates outward K+ flow under simulation conditions at rates comparable to experimental measurements. Additional simulations in which either RY785 or tetraethylammonium (TEA) is introduced in solution show both inhibitors spontaneously enter the channel through the cytoplasmic gate, with distinct effects. In agreement with prior structural studies, we observe that TEA binds to a site adjacent to the selectivity filter, on the pore axis, thereby blocking the flow of K+ ions. RY785, by contrast, binds to the channel walls, off-axis, and allows K+ flow while the cytoplasmic gate remains open. The observed mode of RY785 binding, however, indicates that its mechanism of action is to stabilize and occlude a semi-open state of the gate, by bridging hydrophobic protein-protein interactions therein; this hypothesis would explain the puzzling experimental observation that RY785 recognition influences the gating currents generated by the voltage sensors, 3 nm away.

5.
Heliyon ; 10(19): e38288, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39386881

RESUMO

Gout represents an autoinflammatory disorder instigated by monosodium urate crystals. Its primary manifestation involves the recruitment of diverse immune cell populations, including neutrophils and macrophages. Macrophages assume a pivotal role in the initiation of acute gouty inflammation and subsequent inflammatory cascades. However, recent investigations have revealed that the impact of macrophages on gout is nuanced, extending beyond a solely detrimental influence. Macrophages, characterized by different subtypes, exhibit distinct functionalities that either contribute to the progression or regression of gout. A strategy aimed at modulating macrophage polarization, rather than merely inhibiting inflammation, holds promise for enhancing the efficacy of acute gout treatment. This review centres on elucidating potential mechanisms underlying macrophage polarization in the onset and resolution of gouty inflammation, offering novel insights into the immune equilibrium of macrophages in the context of gout.

6.
Eur J Med Chem ; 280: 116945, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39388907

RESUMO

TLR4 signaling is instrumental in orchestrating multiple aspects of innate immunity. Developing small molecule inhibitors targeting the TLR4 pathway holds potential therapeutic promise for TLR4-related disorders. Herein, an artificial intelligence (AI)-powered next-generation screening approach, employing HelixVS and HelixDock, was utilized to focus on the TLR4-TLR4∗ (a second copy of TLR4) homodimerization surface, leading to the identification of a potent pyrazolo[1,5-a]pyrimidine derivative, designated as compound 1. An extensive structure-activity relationship (SAR) exploration culminated in the discovery of the lead compound TH023, which effectively blocked the LPS-stimulated NF-κB activation and nitric oxide overproduction in HEK-Blue hTLR4 and RAW264.7 cells, with IC50 values of 0.354 and 1.61 µM, respectively. Molecular dynamic (MD) simulations indicated that TH023 stabilized TLR4-MD-2 and disrupted its association with TLR4∗. Moreover, TH023 alleviated the lung injury and decreased pro-inflammatory cytokine levels in LPS-induced septic mice. These findings not only illuminated the strategic advantage of HelixDock in advancing the frontiers of AI-driven drug discovery, but also provided valuable structural insights for the rational design of TLR4-TLR4∗ protein-protein interaction (PPI) inhibitors based on the pyrazolo[1,5-a]pyrimidine scaffold. Overall, this study validated a new strategy for TLR4 signaling regulation by targeting its dimerization, thereby underscoring the therapeutic promise of TH023 in treating TLR4-mediated inflammatory diseases.

7.
J Glob Health ; 14: 04159, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39392073

RESUMO

Background: Global population ageing has brought about new challenges for elderly care. Exploring intrinsic capacity (IC) over time, which is designed as a composite measure of an individual's physical and mental capabilities, is essential for promoting healthy ageing and preventing dependency, such as that emerging from disability in activities of daily living (ADL). We aimed to identify and examine the differences between classes of IC trajectory and onset of ADL disability. Methods: We conducted an observational study using data from three waves (2011-15) of the China Health and Retirement Longitudinal Study, comprising 2609 participants with 6034 observations. IC was measured by five domains, including locomotion, cognition, psychological, sensory capacities, and vitality. We used joint latent class modelling to identify distinct classes with similar patterns of IC trajectory and onset of ADL disability, as well as to explore the variation in IC trajectory and predict five-year risks of ADL disability considering the heterogeneity in the elderly population. Results: The average baseline IC score was 7.15 (range: 0-15). We observed that IC scores slowly decreased with age, with 17.25% of participants developing ADL disability. We identified three classes of IC, which could be described as moderate health (class 1: n = 1634, 62.63%), at-risk (class 2: n = 716, 27.44%; had the highest risk of ADL disability), and optimal health (class 3: n = 259, 9.93%; had the lowest baseline risk of ADL disability). The probability of being in the moderate health class was decreased the most by emotional problems (odds ratio (OR) = 0.219; P < 0.001). Having a self-rated poor standard of living substantially reduced the chances of moderate (OR = 0.308; P = 0.001) and optimal health (OR = 0.110; P < 0.001). Conclusions: Observing IC trajectories and the onset of ADL disability can stratify the elderly into heterogeneous groups, as well as provide data for implementing person-centred care plans to reverse the trend and delay the adverse outcomes in clinical practice.


Assuntos
Atividades Cotidianas , Pessoas com Deficiência , Vida Independente , Humanos , Idoso , Masculino , Feminino , Pessoas com Deficiência/estatística & dados numéricos , Pessoas com Deficiência/psicologia , Estudos Longitudinais , China/epidemiologia , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Avaliação Geriátrica , Avaliação da Deficiência
8.
Nutr Diabetes ; 14(1): 83, 2024 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375333

RESUMO

OBJECTIVE: This study aims to conduct an unbiased assessment of the synergistic effects of non-pharmacological Interventions of intermittent fasting and pulsed radiofrequency energy (PRFE) combination therapy on the facilitation of diabetic wound healing, while also exploring the underlying mechanisms. The findings of this research will provide a theoretical framework and innovative strategy for unconventional therapeutic interventions aimed at enhancing the healing process of diabetes-related wounds. METHODS: In vivo experiments involved the induction of diabetic models in C57 mice through streptozotocin injection. To simulate a combined therapeutic approach, diabetic mice underwent fasting on days 2 and 6, accompanied by twice daily PRFE applications for 8 days. In vitro experiments were conducted using a serum-free culture medium to replicate fasting conditions. The investigation encompassed wound healing rate, proliferation, migration, angiogenesis, oxidative stress, fibrogenesis, and sensory nerve growth through histological analysis and functional assessments in vivo. Additionally, this study utilized quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blotting (WB), and immunofluorescence staining techniques to elucidate the potential mechanisms underlying the effects of intermittent Fasting and PRFE combination therapy in diabetic wound healing, both in vitro and in vivo. RESULTS: The intermittent fasting and PRFE combination therapy demonstrated superior efficacy in enhancing diabetic wound healing compared to either treatment alone. It harnessed the respective strengths of individual therapies, fostering migration, mitigating oxidative stress, and enhancing fibrogenesis. Furthermore, the combination therapy manifested a synergistic effect in promoting proliferation, tube formation, angiogenesis, and sensory nerve growth. CONCLUSION: This study demonstrates that intermittent fasting and PRFE combination therapy enhance diabetic wound healing, effectively leveraging the strengths of both therapies and even yielding synergistic benefits. Moreover, it indicates the potential engagement of the P75/HIF1A/VEGFA axis in mediating these effects.


Assuntos
Diabetes Mellitus Experimental , Jejum , Camundongos Endogâmicos C57BL , Tratamento por Radiofrequência Pulsada , Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Camundongos , Diabetes Mellitus Experimental/terapia , Tratamento por Radiofrequência Pulsada/métodos , Masculino , Terapia Combinada , Estresse Oxidativo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Jejum Intermitente
9.
J Psychiatr Res ; 180: 138-146, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39418882

RESUMO

BACKGROUND: Recent studies have suggested potential impairment of the blood-brain barrier (BBB) in depression. However, due to the limited research and variability in animal models, further investigation using diverse and stable models is necessary. METHODS: A male mouse model of depression was established using the chronic unpredictable mild stress (CUMS) protocol. Following model establishment, depression-like behaviors were assessed using the sucrose preference test, tail suspension test, and forced swimming test. Morphological changes in the hippocampus were examined through hematoxylin-eosin staining. BBB permeability was evaluated using the Evans blue leakage test, fluorescein sodium (NaF) leakage test, and serum S100B content assessment. Gene and protein expression levels of BBB-related proteins in the hippocampus were determined via real-time PCR, western blotting, and immunofluorescence assays. RESULTS: CUMS exposure induced depression-like behaviors, including reduced body weight gain, diminished sucrose preference, and prolonged immobility in both the tail suspension test and forced swimming test. While no significant pathological changes were observed in the hippocampus of either group, increased BBB permeability was noted in the CUMS group, as evidenced by enhanced NaF leakage into the brain parenchyma and elevated serum S100B levels. Gene expression analysis revealed downregulation of angiogenesis-related genes and tight junction proteins in the CUMS group. Additionally, protein levels of tight junction proteins Claudin-5 and ZO-1 were lower in the CUMS group compared to controls. LIMITATIONS: This study is limited to a male mouse model, and the BBB in females is worth exploring in the future. CONCLUSIONS: Increased BBB permeability and decreased expression of tight junction proteins Claudin5 and ZO-1 were observed in mice with CUMS-induced depression.

10.
Anal Chem ; 96(42): 16706-16714, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39387545

RESUMO

The tumor microenvironment (TME), especially with its complicated metabolic characteristics, will dynamically affect the proliferation, migration, and drug response of tumor cells. Rapid metabolic analysis brings out a deeper understanding of the TME, while the susceptibility and environmental dependence of metabolites extremely hinder real-time metabolic profiling since the TME is easily disrupted. Here, we directly integrated paper spray ionization mass spectrometry with a paper-based three-dimensional (3D) tumor model, realizing the rapid capture of metabolic gradients. The entire procedure, from sample preparation to mass spectrometry detection, took less than 4 min, which was able to provide metabolic results close to real time and contributed to understanding the real metabolic processes. At present, our method successfully detected 160 metabolites; notably, over 40 significantly gradient metabolites were revealed across the six layers of the paper-based 3D tumor model. At least 22 gradient metabolites were reported to be associated with cell viability. This strategy was powerful enough to rapidly profile metabolic gradients of a paper-based 3D tumor model for revealing cell viability changes from a metabolomics perspective.


Assuntos
Metabolômica , Papel , Microambiente Tumoral , Humanos , Metabolômica/métodos , Sobrevivência Celular , Espectrometria de Massas por Ionização por Electrospray/métodos , Linhagem Celular Tumoral , Neoplasias/metabolismo , Neoplasias/patologia
11.
Int J Biol Macromol ; 281(Pt 1): 136280, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39368588

RESUMO

Ginkgo biloba, a deciduous tree from the Ginkgoaceae family, is widely cultivated globally. In China, it predominantly grows in the eastern and southern regions. The leaves can be harvested multiple times throughout the growing season, presenting a significant resource potential. Ginkgo biloba leaves are considered as a living fossil with both medicinal and edible properties in traditional Chinese medicine. Polysaccharides, the primary bioactive compounds in these leaves, exhibit numerous biological activities, including antioxidant, antitumor, anti-inflammatory, immunoregulatory activity, antidepressant effects, hepatoprotective, hypoglycemic activity and hair-growth promoting effect. This review highlights the advancements in the extraction separation purification, structural elucidation, and functional analysis of polysaccharides derived from Ginkgo biloba leaves over the past decade, aiming to provide valuable insights for future development and commercialization of Ginkgo biloba leave polysaccharides.

12.
Foods ; 13(20)2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39456324

RESUMO

Rice bran oil is recommended by the World Health Organization as one of the three major healthy edible oils (along with corn and sesame oils), owing to its unique fatty acid composition and functional components. This study screened, organized, and analyzed a large number of studies retrieved through keyword searches, and investigated the nutritional value and safety of rice bran oil. It reviews the stability of raw rice bran materials and the extraction and refining process of rice bran oil and discusses food applications and sub-health regulations. Research has found that a delayed stabilization treatment of rice bran seriously affects the overall quality of rice bran oil. Compared with traditional solvent extraction, the new extraction technologies have improved the yield and nutritional value of rice bran oil, but most of them are still in the research stage. Owing to the lack of economical and applicable supporting production equipment, extraction is difficult to industrialize, which is a challenging research area for the future. Rice bran oil has stronger antioxidant stability than other edible oils and is more beneficial to human health; however, its application scope and consumption are limited owing to the product price and lack of understanding. Rice bran oil has significant antioxidant, anti-inflammatory, anti-cancer, hypoglycemic, lipid-lowering, and neuroprotective effects. Further exploratory research on other unknown functions is required to lay a scientific basis for the application and development of rice bran oil.

13.
Water Res ; 268(Pt A): 122645, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39461213

RESUMO

Phosphorus (P) is a limiting factor in fresh waters and is also the main cause of water eutrophication and deterioration, However, the practical effect of elevated P level on bacterioplankton is less evaluated. In this study, we investigated the bacterioplankton in a 96 hours microcosm experiment with P additions in two forms (organic/inorganic P, OP/IP) and three levels (final conc., 0.040, 0.065 and 0.125 g/L), aiming to find out the response pattern of bacterioplankton in coping with the increasing P levels. Results showed a more dramatic change of water properties and bacterioplankton between P forms (OP and IP) than among the addition levels, and a more remarkable effect of OP addition than the IP. Both OP and IP treatments significantly decreased the water pH, dissolved oxygen (DO), Electrical Conductivity (EC), Nitrate Nitrogen (NO3--N) and Total Organic Carbon (TOC), and reduced the α-diversity of bacterioplankton and relative abundance of Cyanobacteria, but increased the abundance of Proteobacteria. The IP addition decreased Actinobacteria abundance (especially for HgcI) and showed higher denitrification potentials, while the OP addition depressed the Bateroidota and exhibited lowed methylotrophic functions, but such trends decreased with increasing addition concentrations. The network analysis showed that both IP and OP additions increased the proportion of positively correlated edges and reduced the network complexity and stability, but the OP network was more stable than the IP network. The study clarifies the response pattern of bacterioplankton to the P input with different forms and levels, and deepens our understanding of the eutrophication process, which provides a scientific basis for the management and control of freshwater lakes facing eutrophication.

14.
Biochem Biophys Res Commun ; 734: 150737, 2024 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-39388734

RESUMO

Microproteins synthesized through non-canonical translation pathways are frequently found within mitochondria. However, the functional significance of these mitochondria-localized microproteins in energy-intensive organs such as the heart remains largely unexplored. In this study, we demonstrate that the long non-coding RNA CD63-AS1 encodes a mitochondrial microprotein. Notably, in ribosome profiling data of human hearts, there is a positive correlation between the expression of CD63-AS1 and genes associated with cardiomyopathy. We have termed this microprotein CEAM (CD63-AS1 encoded amyloid-like motif containing microprotein), reflecting its sequence characteristics. Our biochemical assays show that CEAM forms protease-resistant aggregates within mitochondria, whereas deletion of the amyloid-like motif transforms CEAM into a soluble cytosolic protein. Overexpression of CEAM triggers mitochondrial stress responses and adversely affect mitochondrial bioenergetics in cultured cardiomyocytes. In turn, the expression of CEAM is reciprocally inhibited by the activation of mitochondrial stresses induced by oligomycin. When expressed in mouse hearts via adeno-associated virus, CEAM impairs cardiac function. However, under conditions of pressure overload-induced cardiac hypertrophy, CEAM expression appears to offer a protective benefit and mitigates the expression of genes associated with cardiac remodeling, presumably through a mechanism that suppresses stress-induced translation reprogramming. Collectively, our study uncovers a hitherto unexplored amyloid-like microprotein expressed in the human cardiomyocytes, offering novel insights into myocardial hypertrophy pathophysiology.


Assuntos
Miócitos Cardíacos , Animais , Humanos , Masculino , Camundongos , Motivos de Aminoácidos , Amiloide/metabolismo , Amiloide/genética , Proteínas Amiloidogênicas/metabolismo , Proteínas Amiloidogênicas/genética , Células Cultivadas , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/genética , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/genética , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Tetraspanina 30/genética
15.
ACS Appl Mater Interfaces ; 16(43): 58872-58879, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39415430

RESUMO

High-power piezoelectric ceramics typically operate under severe conditions. This makes the accurate evaluation of their high-power performances through pure quasi-static parameters challenging. The 0.94PbZr0.5Ti0.5O3 - 0.06Pb(Mn1/3Nb2/3)O3 + 0.005Fe2O3 + 0.002Sc2O3 (PZT-1) ceramic exhibits exceptional and reliable high-power performances at elevated temperatures and under loading conditions. While numerous PZT-based ceramics demonstrate excellent quasi-static parameters, only the PZT-1 ceramic displays superior high-field parameters, such as a low tan δ of 0.97% at 566 V/mm (1 kHz) and a large Qm of 1164 at 50 V/mm (100 kHz). Therefore, the PZT-1 ceramic demonstrates remarkably slow heat generation and the highest surface temperatures are only 41.8 °C at 50 V/mm (100 kHz). Moreover, the PZT-1 ceramic shows a minimal resonance frequency variation of -0.04% in the temperature range of 25-120 °C at 50 V/mm. Consequently, the PZT-1 ceramic maintains a high and reliable vibration velocity of 0.90 m/s at 120 °C for 30 min, and the ceramic cantilever sustains a high amplitude of 7 µm, significantly outperforming other ceramics. This study conclusively demonstrates that high-field parameters, rather than quasi-static parameters, are more effective in accurately estimating the high-power performances of ceramics.

16.
Front Artif Intell ; 7: 1460364, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39474601

RESUMO

In recent years, large language models (LLMs) have seen rapid advancement and adoption, and are increasingly being used in educational contexts. In this perspective article, we explore the open challenge of leveraging LLMs to create personalized learning environments that support the "whole learner" by modeling and adapting to both cognitive and non-cognitive characteristics. We identify three key challenges toward this vision: (1) improving the interpretability of LLMs' representations of whole learners, (2) implementing adaptive technologies that can leverage such representations to provide tailored pedagogical support, and (3) authoring and evaluating LLM-based educational agents. For interpretability, we discuss approaches for explaining LLM behaviors in terms of their internal representations of learners; for adaptation, we examine how LLMs can be used to provide context-aware feedback and scaffold non-cognitive skills through natural language interactions; and for authoring, we highlight the opportunities and challenges involved in using natural language instructions to specify behaviors of educational agents. Addressing these challenges will enable personalized AI tutors that can enhance learning by accounting for each student's unique background, abilities, motivations, and socioemotional needs.

17.
Food Chem X ; 24: 101864, 2024 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-39403296

RESUMO

Chinese baijiu is highly regarded for its unique flavor, and a variety of crops can be utilized as raw materials in its production. Waxy crops are essential ingredients in the brewing of high-quality baijiu; however, there is currently no comprehensive identification of volatile organic compounds (VOCs) and non-volatile compounds (N-VOCs) in waxy wheat baijiu (WWB). This study aims to investigate the dynamic changes of VOCs and N-VOCs in WWB during several important time periods from new to aged. A total of 25 amino acids underwent changes in the samples, with numerous physiologically active beneficial amino acids showing significant accumulation after aging. Additionally, 517 VOCs changed after aging, predominantly comprising esters and terpenoids, with 72 major VOCs being identified. A total of 718 metabolites were identified in the metabolome, primarily comprising alterations in lipids, amino acids, phenolic acids, organic acids, and alkaloids. These metabolites significantly influenced the levels of amino acids and VOCs. Our study is the first to provide a comprehensive examination of these aspects of WWB, highlighting its unique advantages over other crops. We believe that this research will establish a theoretical foundation for the application of waxy wheat in the baijiu industry, improve baijiu quality, and promote the development of functional baijius.

18.
Sci Rep ; 14(1): 25448, 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39455808

RESUMO

The emergence of nanogenerators, which have the ability to capture mechanical energy from the environment and to collect and transmit tiny energy, is rapidly becoming a hot research topic. The performance of electrode materials is the key to the efficiency of nanogenerators. Covalent organic skeletons (COFs), a class of crystalline organic porous materials with the advantages of large specific surface area, high porosity, tunable structure, and flexible tailorability, have very significant advantages in being used as nanogenerator materials. In this paper, we synthesised two COF materials to investigate the effect of the introduction of active metals on the friction power generation performance of COFs without changing their topology, COF-2 containing zinc ions is capable of generating a short-circuit current of 107.5 µA during friction. The porous structure increases the effective contact area to form a larger charge density, and the introduction of metal ions can accelerate the charge separation and transport. The two bidirectional synergistic effects of the materials significantly improve the output performance of the nanogenerator, and a simple and efficient method is explored for the enhancement of the output performance of COF-based triboelectric nanogenerators.

19.
Nano Lett ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39475408

RESUMO

Contrary to oxide or polymeric glasses, metallic glasses are infamously known for their relatively limited thermal stability, which is often characterized by their narrow supercooled liquid regions. Nonetheless, we successfully fabricated metallic-glass based nanomembranes with an ultrahigh thermal ability by a polymer surface buckling enabled exfoliation technique. These nanomembranes exhibit a distinctive nanostructure with nanosized metallic-glasses encapsulated within an interconnected nanoamorphous-oxide network. Due to a pronounced nanoconfinement effect, crystallization is significantly suppressed. Consequently, these oxidized metallic-glass nanomembranes initiate a glass transition at 324 K at a heating rate of 10 K/min. Remarkably, they also showcase an expansive supercooled liquid region of 448 K, surpassing various metallic and oxide glasses reported. Furthermore, these nanomembranes not only exhibit a low elastic modulus but also achieve superplasticity even at room temperature. This unique blend of thermomechanical properties positions our metallic-glass based nanomembranes as an ideal candidate for nanofabrication processing, such as nanoimprinting, for the creation of next-generation nanodevices.

20.
Chem Commun (Camb) ; 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39470744

RESUMO

Charge-redistributed Co3O4/Fe0.3Co0.7P heterointerfaces are designed for effective electrocatalytic urea oxidation in alkaline medium, delivering excellent performance with only 1.41 V vs. RHE at 100 mA cm-2, low Tafel slope of 74 mV dec-1 and 36-h robust stability. The fine regulation of charge redistribution through heterointerfaces provides an effective strategy to design highly efficient electrocatalysts.

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