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1.
Brain Topogr ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042322

RESUMO

Functional near-infrared spectroscopy (fNIRS), a non-invasive optical neuroimaging technique that is portable and acoustically silent, has become a promising tool for evaluating auditory brain functions in hearing-vulnerable individuals. This study, for the first time, used fNIRS to evaluate neuroplasticity of speech-in-noise processing in older adults. Ten older adults, most of whom had moderate-to-mild hearing loss, participated in a 4-week speech-in-noise training. Their speech-in-noise performances and fNIRS brain responses to speech (auditory sentences in noise), non-speech (spectrally-rotated speech in noise) and visual (flashing chequerboards) stimuli were evaluated pre- (T0) and post-training (immediately after training, T1; and after a 4-week retention, T2). Behaviourally, speech-in-noise performances were improved after retention (T2 vs. T0) but not immediately after training (T1 vs. T0). Neurally, we intriguingly found brain responses to speech vs. non-speech decreased significantly in the left auditory cortex after retention (T2 vs. T0 and T2 vs. T1) for which we interpret as suppressed processing of background noise during speech listening alongside the significant behavioural improvements. Meanwhile, functional connectivity within and between multiple regions of temporal, parietal and frontal lobes was significantly enhanced in the speech condition after retention (T2 vs. T0). We also found neural changes before the emergence of significant behavioural improvements. Compared to pre-training, responses to speech vs. non-speech in the left frontal/prefrontal cortex were decreased significantly both immediately after training (T1 vs. T0) and retention (T2 vs. T0), reflecting possible alleviation of listening efforts. Finally, connectivity was significantly decreased between auditory and higher-level non-auditory (parietal and frontal) cortices in response to visual stimuli immediately after training (T1 vs. T0), indicating decreased cross-modal takeover of speech-related regions during visual processing. The results thus showed that neuroplasticity can be observed not only at the same time with, but also before, behavioural changes in speech-in-noise perception. To our knowledge, this is the first fNIRS study to evaluate speech-based auditory neuroplasticity in older adults. It thus provides important implications for current research by illustrating the promises of detecting neuroplasticity using fNIRS in hearing-vulnerable individuals.

2.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000154

RESUMO

Putatively, tooth agenesis was attributed to the initiation failure of tooth germs, though little is known about the histological and molecular alterations. To address if constitutively active FGF signaling is associated with tooth agenesis, we activated Fgf8 in dental mesenchyme with Osr-cre knock-in allele in mice (Osr2-creKI; Rosa26R-Fgf8) and found incisor agenesis and molar microdontia. The cell survival assay showed tremendous apoptosis in both the Osr2-creKI; Rosa26R-Fgf8 incisor epithelium and mesenchyme, which initiated incisor regression from cap stage. In situ hybridization displayed vanished Shh transcription, and immunostaining exhibited reduced Runx2 expression and enlarged mesenchymal Lef1 domain in Osr2-creKI; Rosa26R-Fgf8 incisors, both of which were suggested to enhance apoptosis. In contrast, Osr2-creKI; Rosa26R-Fgf8 molar germs displayed mildly suppressed Shh transcription, and the increased expression of Ectodin, Runx2 and Lef1. Although mildly smaller than WT controls prenatally, the Osr2-creKI; Rosa26R-Fgf8 molar germs produced a miniature tooth with impaired mineralization after a 6-week sub-renal culture. Intriguingly, the implanted Osr2-creKI; Rosa26R-Fgf8 molar germs exhibited delayed odontoblast differentiation and accelerated ameloblast maturation. Collectively, the ectopically activated Fgf8 in dental mesenchyme caused incisor agenesis by triggering incisor regression and postnatal molar microdontia. Our findings reported tooth agenesis resulting from the regression from the early bell stage and implicated a correlation between tooth agenesis and microdontia.


Assuntos
Fator 8 de Crescimento de Fibroblasto , Incisivo , Mesoderma , Dente Molar , Animais , Fator 8 de Crescimento de Fibroblasto/genética , Fator 8 de Crescimento de Fibroblasto/metabolismo , Camundongos , Incisivo/anormalidades , Incisivo/metabolismo , Mesoderma/metabolismo , Mesoderma/patologia , Dente Molar/anormalidades , Dente Molar/metabolismo , Anodontia/genética , Anodontia/metabolismo , Anodontia/patologia , Apoptose , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Fator 1 de Ligação ao Facilitador Linfoide/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Transdução de Sinais , Regulação da Expressão Gênica no Desenvolvimento , Odontogênese/genética , Camundongos Transgênicos
3.
Biophys Rep ; 10(3): 175-177, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39027319
4.
Medicine (Baltimore) ; 103(29): e38861, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39029026

RESUMO

Osteoporosis (OP) constitutes a notable public health concern that significantly impacts the skeletal health of the global aging population. Its prevalence is steadily escalating, yet the intricacies of its diagnosis and treatment remain challenging. Recent investigations have illuminated a profound interlink between gut microbiota (GM) and bone metabolism, thereby opening new avenues for probing the causal relationship between GM and OP. Employing Mendelian randomization (MR) as the investigative tool, this study delves into the causal rapport between 211 varieties of GM and OP. The data are culled from genome-wide association studies (GWAS) conducted by the MiBioGen consortium, in tandem with OP genetic data gleaned from the UK Biobank, BioBank Japan Project, and the FinnGen database. A comprehensive repertoire of statistical methodologies, encompassing inverse-variance weighting, weighted median, Simple mode, Weighted mode, and MR-Egger regression techniques, was adroitly harnessed for meticulous analysis. The discernment emerged that the genus Coprococcus3 is inversely associated with OP, potentially serving as a deterrent against its onset. Additionally, 21 other gut microbial species exhibited a positive correlation with OP, potentially accentuating its proclivity and progression. Subsequent to rigorous scrutiny via heterogeneity and sensitivity analyses, these findings corroborate the causal nexus between GM and OP. Facilitated by MR, this study successfully elucidates the causal underpinning binding GM and OP, thereby endowing invaluable insights for deeper exploration into the pivotal role of GM in the pathogenesis of OP.


Assuntos
Microbioma Gastrointestinal , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Osteoporose , Humanos , Análise da Randomização Mendeliana/métodos , Osteoporose/prevenção & controle , Osteoporose/genética , Osso e Ossos/metabolismo
5.
ACS Nano ; 18(27): 17570-17577, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934625

RESUMO

The coupling of mechanical deformation and electrical stimuli at the nanoscale has been the subject of intense investigation in the realm of materials science. Recently, twisted van der Waals (vdW) materials have emerged as a platform for exploring exotic quantum states. These states are intimately tied to the formation of moiré superlattices, which can be visualized by directly exploiting the electromechanical response. However, the origin of the response, even in twisted bilayer graphene (tBLG), remains unsettled. Here, employing lateral piezoresponse force microscopy (LPFM), we investigate the electromechanical responses of marginally twisted graphene moiré superlattices with different layer thicknesses. We observe distinct LPFM amplitudes and spatial profiles in tBLG and twisted monolayer-bilayer graphene (tMBG), exhibiting effective in-plane piezoelectric coefficients of 0.05 and 0.35 pm/V, respectively. Force tuning experiments further underscored a marked divergence in their responses. The contrasting behaviors suggest different electromechanical couplings in tBLG and tMBG. In tBLG, the response near the domain walls is attributed to the flexoelectric effect, while in tMBG, the behaviors can be comprehended within the context of the piezoelectric effect. Our results not only provide insights into electromechanical and corporative effects in twisted vdW materials with different stacking symmetries but may also offer a way to engineer them at the nanoscale.

6.
Histopathology ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747491

RESUMO

BACKGROUND AND AIMS: Evaluation of the programmed cell death ligand-1 (PD-L1) combined positive score (CPS) is vital to predict the efficacy of the immunotherapy in triple-negative breast cancer (TNBC), but pathologists show substantial variability in the consistency and accuracy of the interpretation. It is of great importance to establish an objective and effective method which is highly repeatable. METHODS: We proposed a model in a deep learning-based framework, which at the patch level incorporated cell analysis and tissue region analysis, followed by the whole-slide level fusion of patch results. Three rounds of ring studies (RSs) were conducted. Twenty-one pathologists of different levels from four institutions evaluated the PD-L1 CPS in TNBC specimens as continuous scores by visual assessment and our artificial intelligence (AI)-assisted method. RESULTS: In the visual assessment, the interpretation results of PD-L1 (Dako 22C3) CPS by different levels of pathologists have significant differences and showed weak consistency. Using AI-assisted interpretation, there were no significant differences between all pathologists (P = 0.43), and the intraclass correlation coefficient (ICC) value was increased from 0.618 [95% confidence interval (CI) = 0.524-0.719] to 0.931 (95% CI = 0.902-0.955). The accuracy of interpretation result is further improved to 0.919 (95% CI = 0.886-0.947). Acceptance of AI results by junior pathologists was the highest among all levels, and 80% of the AI results were accepted overall. CONCLUSION: With the help of the AI-assisted diagnostic method, different levels of pathologists achieved excellent consistency and repeatability in the interpretation of PD-L1 (Dako 22C3) CPS. Our AI-assisted diagnostic approach was proved to strengthen the consistency and repeatability in clinical practice.

7.
Nano Lett ; 24(23): 6931-6938, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38804717

RESUMO

Spin-orbit torque magnetic random access memory (SOT-MRAM) has great promise in high write speed and low power consumption. Mo can play a vital role in constructing a CoFeB/MgO-based MRAM cell because of its ability to enhance the perpendicular magnetic anisotropy (PMA), thermal tolerance, and tunneling magnetoresistance. However, Mo is often considered as a less favorable candidate among SOT materials because of its weak spin-orbit coupling. In this study, we experimentally investigate the SOT efficiencies in Mo/CoFeB/MgO heterostructures over a wide range of Mo thicknesses and temperature. Decent damping-like SOT efficiency |ξDL| = 0.015 ± 0.001 and field-like SOT efficiency |ξFL| = 0.050 ± 0.001 are found in amorphous Mo. The ξFL/ξDL ratio is greater than 3. Furthermore, efficient current-induced magnetization switching is demonstrated with the critical current density comparable with heavy metal Ir and W. Our work reveals new understanding and possibilities for Mo as both an SOT source component and PMA buffer layer in the implementation of SOT-MRAMs.

8.
medRxiv ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38699369

RESUMO

Multi-ancestry statistical fine-mapping of cis-molecular quantitative trait loci (cis-molQTL) aims to improve the precision of distinguishing causal cis-molQTLs from tagging variants. However, existing approaches fail to reflect shared genetic architectures. To solve this limitation, we present the Sum of Shared Single Effects (SuShiE) model, which leverages LD heterogeneity to improve fine-mapping precision, infer cross-ancestry effect size correlations, and estimate ancestry-specific expression prediction weights. We apply SuShiE to mRNA expression measured in PBMCs (n=956) and LCLs (n=814) together with plasma protein levels (n=854) from individuals of diverse ancestries in the TOPMed MESA and GENOA studies. We find SuShiE fine-maps cis-molQTLs for 16% more genes compared with baselines while prioritizing fewer variants with greater functional enrichment. SuShiE infers highly consistent cis-molQTL architectures across ancestries on average; however, we also find evidence of heterogeneity at genes with predicted loss-of-function intolerance, suggesting that environmental interactions may partially explain differences in cis-molQTL effect sizes across ancestries. Lastly, we leverage estimated cis-molQTL effect-sizes to perform individual-level TWAS and PWAS on six white blood cell-related traits in AOU Biobank individuals (n=86k), and identify 44 more genes compared with baselines, further highlighting its benefits in identifying genes relevant for complex disease risk. Overall, SuShiE provides new insights into the cis-genetic architecture of molecular traits.

9.
Sci Total Environ ; 933: 173057, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729372

RESUMO

Dimethylsulfoniopropionate (DMSP), a key organic sulfur compound in marine and subseafloor sediments, is degraded by phytoplankton and bacteria, resulting in the release of the climate-active volatile gas dimethylsulfide (DMS). However, it remains unclear if dominant eukaryotic fungi in subseafloor sediments possess specific abilities and metabolic mechanisms for DMSP degradation and DMS formation. Our study provides the first evidence that fungi from coal-bearing sediments ∼2 km below the seafloor, such as Aspergillus spp., Chaetomium globosum, Cladosporium sphaerospermum, and Penicillium funiculosum, can degrade DMSP and produce DMS. In Aspergillus sydowii 29R-4-F02, which exhibited the highest DMSP-dependent DMS production rate (16.95 pmol/µg protein/min), two DMSP lyase genes, dddP and dddW, were identified. Remarkably, the dddW gene, previously observed only in bacteria, was found to be crucial for fungal DMSP cleavage. These findings not only extend the list of fungi capable of degrading DMSP, but also enhance our understanding of DMSP lyase diversity and the role of fungi in DMSP decomposition in subseafloor sedimentary ecosystems.


Assuntos
Fungos , Compostos de Sulfônio , Compostos de Sulfônio/metabolismo , Fungos/metabolismo , Sedimentos Geológicos/microbiologia , Sulfetos/metabolismo , Biodegradação Ambiental , Liases de Carbono-Enxofre/metabolismo
10.
Small ; : e2403136, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770989

RESUMO

Hollandite-type manganese dioxide (α-MnO2) is recognized as a promising cathode material upon high-performance aqueous zinc-ion batteries (ZIBs) owing to the high theoretical capacities, high working potentials, unique Zn2+/H+ co-insertion chemistry, and environmental friendliness. However, its practical applications limited by Zn2+ accommodation, where the strong coulombic interaction and sluggish kinetics cause significant lattice deformation, fast capacity degradation, insufficient rate capability, and undesired interface degradation. It remains challenging to accurately modulate H+ intercalation while suppressing Zn2+ insertion for better lattice stability and electrochemical kinetics. Herein, proton Grotthuss transfer channels are first tunneled by shielding MnO2 with hydrophilic-zincophobic heterointerface, fulfilling the H+-dominating diffusion with the state-of-the-art ZIBs performance. Local atomic structure and theoretical simulation confirm that surface-engineered α-MnO2 affords to the synergy of Mn electron t2g-eg activation, oxygen vacancy enrichment, selective H+ Grotthuss transfer, and accelerated desolvation kinetics. Consequently, fortified α-MnO2 achieves prominent low current density cycle stability (≈100% capacity retention at 1 C after 400 cycles), remarkable long-lifespan cycling performance (98% capacity retention at 20 C after 12 000 cycles), and ultrafast rate performance (up to 30 C). The study exemplifies a new approach of heterointerface engineering for regulation of H+-dominating Grotthuss transfer and lattice stabilization in α-MnO2 toward reliable ZIBs.

11.
J Med Chem ; 67(10): 8201-8224, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38736187

RESUMO

Although vaccination remains the prevalent prophylactic means for controlling Influenza A virus (IAV) infections, novel structural antivirus small-molecule drugs with new mechanisms of action for treating IAV are highly desirable. Herein, we describe a modular biomimetic strategy to expeditiously achieve a new class of macrocycles featuring oxime, which might target the hemagglutinin (HA)-mediated IAV entry into the host cells. SAR analysis revealed that the size and linker of the macrocycles play an important role in improving potency. Particularly, as a 14-membered macrocyclic oxime, 37 exhibited potent inhibitory activity against IAV H1N1 with an EC50 value of 23 nM and low cytotoxicity, which alleviated cytopathic effects and protected cell survival obviously after H1N1 infection. Furthermore, 37 showed significant synergistic activity with neuraminidase inhibitor oseltamivir in vitro.


Assuntos
Antivirais , Vírus da Influenza A Subtipo H1N1 , Compostos Macrocíclicos , Oximas , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Oximas/farmacologia , Oximas/química , Oximas/síntese química , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Relação Estrutura-Atividade , Humanos , Cães , Compostos Macrocíclicos/farmacologia , Compostos Macrocíclicos/química , Compostos Macrocíclicos/síntese química , Animais , Células Madin Darby de Rim Canino , Descoberta de Drogas , Biomimética , Oseltamivir/farmacologia , Oseltamivir/química
12.
J Hazard Mater ; 473: 134681, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788580

RESUMO

Tetracyclines are widely used in Chinese apiculture. However, limited information is available on the presence of tetracycline residues in honey and the sources, degradation patterns, and associated health risks of these compounds. In this study, the presence of tetracyclines in honey samples across China was investigated over a four-year period. Additionally, the risks of dietary intake, as well as the sources and degradation patterns of tetracyclines in honey, were assessed. The three-dimensional spatial distributions (floral region, geographical region and entomological origin) of tetracyclines contamination varied significantly. Tetracycline residues in honey posed a moderate risk to children aged 3-10 years in Northwest China. Source analysis indicated that colony migration serves as the primary source of tetracyclines in honey. Based on the degradation patterns of tetracyclines in honey within colonies and during storage, oxytetracycline is more readily degraded than other tetracyclines. The main degradation products of tetracyclines are epimers and dehydration products, and the effects of these products on human health and the environment should be further evaluated in future studies. This comprehensive investigation provides valuable insights into the safe use and regulation of tetracyclines in Chinese apiculture.


Assuntos
Antibacterianos , Mel , Tetraciclinas , Mel/análise , China , Tetraciclinas/análise , Humanos , Antibacterianos/análise , Antibacterianos/toxicidade , Medição de Risco , Contaminação de Alimentos/análise , Criança , Pré-Escolar
13.
Int J Biol Macromol ; 270(Pt 2): 132262, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734356

RESUMO

Exopolysaccharide produced by lactic acid bacteria has various functions. In the present study, one anti-oxidant polysaccharide fraction, namely S1-EPS, was extracted and purified from Pediococcus acidilactici S1, and its structure and its potential effect on the gel properties of fat substitute meat mince were investigated. The results showed that S1-EPS, one of homogeneous polysaccharides, was mainly composed of Gal, Glc, and Man in molar ratio of 7.61: 15.25: 77.13 and molecular weight of 46.975 kDa. The backbone of EPS-S1 contained →2,6)-α-D-Manp-(1→,→2)-α-D-Manp-(1→,→3)-α-D-Glcp-(1 → and a small amount of→6)-ß-D-Manp-(1→. The linkages of branches in EPS-S1 were mainly composed of α-D-Manp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-2 or ß-D-Galp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-6. Furthermore, as S1-EPS increased, the meat minced gel pores decreased, and the surface became smooth. A remarkable inhibitory effect on the lipid oxidation of meat minced gel was found as S1-EPS concentration increased. Overall, S1-EPS was found to have substantial potential in low-fat meat products by serving as a natural, anti-oxidant, and functional additive.


Assuntos
Substitutos da Gordura , Pediococcus acidilactici , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Pediococcus acidilactici/metabolismo , Pediococcus acidilactici/química , Substitutos da Gordura/química , Peso Molecular , Antioxidantes/química , Antioxidantes/farmacologia , Géis/química , Produtos da Carne/microbiologia
14.
Nat Metab ; 6(5): 933-946, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609677

RESUMO

Streptomyces has the largest repertoire of natural product biosynthetic gene clusters (BGCs), yet developing a universal engineering strategy for each Streptomyces species is challenging. Given that some Streptomyces species have larger BGC repertoires than others, we proposed that a set of genes co-evolved with BGCs to support biosynthetic proficiency must exist in those strains, and that their identification may provide universal strategies to improve the productivity of other strains. We show here that genes co-evolved with natural product BGCs in Streptomyces can be identified by phylogenomics analysis. Among the 597 genes that co-evolved with polyketide BGCs, 11 genes in the 'coenzyme' category have been examined, including a gene cluster encoding for the cofactor pyrroloquinoline quinone. When the pqq gene cluster was engineered into 11 Streptomyces strains, it enhanced production of 16,385 metabolites, including 36 known natural products with up to 40-fold improvement and several activated silent gene clusters. This study provides an innovative engineering strategy for improving polyketide production and finding previously unidentified BGCs.


Assuntos
Produtos Biológicos , Família Multigênica , Streptomyces , Produtos Biológicos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Policetídeos/metabolismo , Evolução Molecular , Vias Biossintéticas/genética , Filogenia , Engenharia Metabólica/métodos
15.
Phytomedicine ; 129: 155650, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38669971

RESUMO

BACKGROUND: Disruption of stem cell and microbial homeostasis accelerates the aging process. Hence, maintaining these balances effectively delays aging and alleviates the symptoms of age-related diseases. Recent research indicates that targeting endoplasmic reticulum (ER) stress and immune deficiency (IMD) signalling may play a positive role in maintaining homeostasis in aging intestinal stem cells (ISC) and microbial equilibrium. Previous research has suggested that total ginsenosides (TG) derived from Panax ginseng C. A. Meyer may exhibit potential anti-aging properties by mitigating ER stress and mediating the IMD pathway. Nevertheless, it remains unclear whether TG improve ISC and microbial homeostasis by modulating ER stress and the IMD pathway to promote healthy aging. PURPOSE: To elucidate whether TG promotes healthspan in Drosophila and its underlying molecular mechanisms, focusing on its role in regulating ER stress and the IMD pathway to maintain ISC and intestinal microbiota homeostasis. METHODS: High performance liquid chromatography was performed to detect the main saponin monomer in TG. Survival rate, gut length, barrier function, and feeding/excretion behaviour assays were used to evaluate the effects of TG on the lifespan and gut health of Drosophila. At the stem cell level, "esg-luciferase" reporter system, esg-GFP/delta stem cell fluorescent labelling, and phospho-histone H3+ mitotic activity assays were employed to determine whether TG prevented natural aging or oxidative stress-associated ISC over-proliferation in Drosophila. Immunofluorescence staining was used to detect the effects of TG on ER stress during aging. Overexpression or interference of ER stress target genes and their related c-Jun N-terminal kinase (JNK) gene was manipulated using gene editing technology to verify the molecular mechanism by which TG maintains age-related ISC proliferation homeostasis. Molecular docking and isothermal titration calorimetry were used to verify the direct interactions between TG and ER stress target genes. In addition, at the intestinal flora level, 16S rDNA sequencing was used to analyse the effect of TG on the diversity and abundance of Drosophila intestinal flora and the possible functional pathways involved. RT-qPCR was performed to determine whether TG mediated the expression of target genes in the IMD pathway. A dominant bacterial species-specific mono-association analysis were performed to verify whether the effects of TG on IMD target genes and ISC proliferation depended on the direct control of the dominant bacterial species. RESULTS: Our results suggest that administration of TG delays the decline in gut morphology and function in aging Drosophila. TG prevents age-associated ISC hyperproliferation by inhibiting ER stress IRE1-mediated JNK signaling. Furthermore, oral TG prevented aging-associated ISC and gut microbiota dysbiosis by remodelling the gut microbiota and inhibiting Acetobacter-mediated activation of IMD target genes. CONCLUSION: TG promotes healthy aging by inhibiting the excessive proliferation of ISC and alleviating intestinal microbial imbalance, thereby providing new insights for the research and development of anti-aging TG products.


Assuntos
Estresse do Retículo Endoplasmático , Microbioma Gastrointestinal , Ginsenosídeos , Intestinos , Células-Tronco , Animais , Células-Tronco/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Ginsenosídeos/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Panax/química , Envelhecimento/efeitos dos fármacos , Drosophila melanogaster/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Drosophila/efeitos dos fármacos , Longevidade/efeitos dos fármacos
16.
Cyborg Bionic Syst ; 5: 0103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617112

RESUMO

Soft grippers due to their highly compliant material and self-adaptive structures attract more attention to safe and versatile grasping tasks compared to traditional rigid grippers. However, those flexible characteristics limit the strength and the manipulation capacity of soft grippers. In this paper, we introduce a hybrid-driven gripper design utilizing origami finger structures, to offer adjustable finger stiffness and variable grasping range. This gripper is actuated via pneumatic and cables, which allows the origami structure to be controlled precisely for contraction and extension, thus achieving different finger lengths and stiffness by adjusting the cable lengths and the input pressure. A kinematic model of the origami finger is further developed, enabling precise control of its bending angle for effective grasping of diverse objects and facilitating in-hand manipulation. Our proposed design method enriches the field of soft grippers, offering a simple yet effective approach to achieve safe, powerful, and highly adaptive grasping and in-hand manipulation capabilities.

17.
Comput Struct Biotechnol J ; 23: 1439-1449, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38623561

RESUMO

Artificial intelligence (AI) holds significant promise in transforming medical imaging, enhancing diagnostics, and refining treatment strategies. However, the reliance on extensive multicenter datasets for training AI models poses challenges due to privacy concerns. Federated learning provides a solution by facilitating collaborative model training across multiple centers without sharing raw data. This study introduces a federated attention-consistent learning (FACL) framework to address challenges associated with large-scale pathological images and data heterogeneity. FACL enhances model generalization by maximizing attention consistency between local clients and the server model. To ensure privacy and validate robustness, we incorporated differential privacy by introducing noise during parameter transfer. We assessed the effectiveness of FACL in cancer diagnosis and Gleason grading tasks using 19,461 whole-slide images of prostate cancer from multiple centers. In the diagnosis task, FACL achieved an area under the curve (AUC) of 0.9718, outperforming seven centers with an average AUC of 0.9499 when categories are relatively balanced. For the Gleason grading task, FACL attained a Kappa score of 0.8463, surpassing the average Kappa score of 0.7379 from six centers. In conclusion, FACL offers a robust, accurate, and cost-effective AI training model for prostate cancer pathology while maintaining effective data safeguards.

18.
Nat Commun ; 15(1): 2110, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454003

RESUMO

Pilot-diesel-ignition ammonia combustion engines have attracted widespread attentions from the maritime sector, but there are still bottleneck problems such as high unburned NH3 and N2O emissions as well as low thermal efficiency that need to be solved before further applications. In this study, a concept termed as in-cylinder reforming gas recirculation is initiated to simultaneously improve the thermal efficiency and reduce the unburned NH3, NOx, N2O and greenhouse gas emissions of pilot-diesel-ignition ammonia combustion engine. For this concept, one cylinder of the multi-cylinder engine operates rich of stoichiometric and the excess ammonia in the cylinder is partially decomposed into hydrogen, then the exhaust of this dedicated reforming cylinder is recirculated into the other cylinders and therefore the advantages of hydrogen-enriched combustion and exhaust gas recirculation can be combined. The results show that at 3% diesel energetic ratio and 1000 rpm, the engine can increase the indicated thermal efficiency by 15.8% and reduce the unburned NH3 by 89.3%, N2O by 91.2% compared to the base/traditional ammonia engine without the proposed method. At the same time, it is able to reduce carbon footprint by 97.0% and greenhouse gases by 94.0% compared to the traditional pure diesel mode.

19.
Sci Bull (Beijing) ; 69(10): 1427-1436, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38531717

RESUMO

Developing low-power FETs holds significant importance in advancing logic circuits, especially as the feature size of MOSFETs approaches sub-10 nanometers. However, this has been restricted by the thermionic limitation of SS, which is limited to 60 mV per decade at room temperature. Herein, we proposed a strategy that utilizes 2D semiconductors with an isolated-band feature as channels to realize sub-thermionic SS in MOSFETs. Through high-throughput calculations, we established a guiding principle that combines the atomic structure and orbital interaction to identify their sub-thermionic transport potential. This guides us to screen 192 candidates from the 2D material database comprising 1608 systems. Additionally, the physical relationship between the sub-thermionic transport performances and electronic structures is further revealed, which enables us to predict 15 systems with promising device performances for low-power applications with supply voltage below 0.5 V. This work opens a new way for the low-power electronics based on 2D materials and would inspire extensive interests in the experimental exploration of intrinsic steep-slope MOSFETs.

20.
Natl Sci Rev ; 11(3): nwae001, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38312376

RESUMO

This Perspective aims to provide a concise survey of current progress and outlook future directions in high-performance transistors and integrated circuits (ICs) based on 2D semiconductors.

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