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1.
Sensors (Basel) ; 24(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39123989

RESUMO

In order to shorten detection times and improve average precision in embedded devices, a lightweight and high-accuracy model is proposed to detect passion fruit in complex environments (e.g., with backlighting, occlusion, overlap, sun, cloud, or rain). First, replacing the backbone network of YOLOv5 with a lightweight GhostNet model reduces the number of parameters and computational complexity while improving the detection speed. Second, a new feature branch is added to the backbone network and the feature fusion layer in the neck network is reconstructed to effectively combine the lower- and higher-level features, which improves the accuracy of the model while maintaining its lightweight nature. Finally, a knowledge distillation method is used to transfer knowledge from the more capable teacher model to the less capable student model, significantly improving the detection accuracy. The improved model is denoted as G-YOLO-NK. The average accuracy of the G-YOLO-NK network is 96.00%, which is 1.00% higher than that of the original YOLOv5s model. Furthermore, the model size is 7.14 MB, half that of the original model, and its real-time detection frame rate is 11.25 FPS when implemented on the Jetson Nano. The proposed model is found to outperform state-of-the-art models in terms of average precision and detection performance. The present work provides an effective model for real-time detection of passion fruit in complex orchard scenes, offering valuable technical support for the development of orchard picking robots and greatly improving the intelligence level of orchards.

2.
Adv Mater ; 34(39): e2203744, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35951671

RESUMO

Zinc-ion capacitors (ZICs) are promising technology for large-scale energy storage by integrating the attributes of supercapacitors and zinc-ion batteries. Unfortunately, the insufficient Zn2+ -storage active sites of carbonaceous cathode materials and the mismatch of pore sizes with charge carriers lead to unsatisfactory Zn2+ storage capability. Herein, new insights for boosting Zn2+ storage capability of activated nitrogen-doped hierarchical porous carbon materials (ANHPC-x) are reported by effectively eliminating the micropore confinement effect and synchronously elevating the utilization of active sites. Therefore, the best-performed ANHPC-2 delivers impressive electrochemical properties for ZICs in terms of excellent capacity (199.1 mAh g-1 ), energy density (155.2 Wh kg-1 ), and durability (65 000 cycles). Systematic ex situ characterizations together with in situ electrochemical quartz crystal microbalance and Raman spectra measurements reveal that the remarkable electrochemical performance is assigned to the synergism of the Zn2+ , H+ , and SO4 2- co-adsorption mechanism and reversible chemical adsorption. Furthermore, the ANHPC-2-based quasi-solid-state ZIC demonstrates excellent electrochemical capability with an ultralong lifespan of up to 100 000 cycles. This work not only provides a promising strategy to improve the Zn2+ storage capability of carbonaceous materials but also sheds lights on charge-storage mechanism and advanced electrode materials' design for ZICs toward practical applications.

3.
ACS Nano ; 16(2): 2877-2888, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35129326

RESUMO

Zinc ion capacitors (ZICs) hold great promise in large-scale energy storage by inheriting the superiorities of zinc ion batteries and supercapacitors. However, the mismatch of kinetics and capacity between a Zn anode and a capacitive-type cathode is still the Achilles' heel of this technology. Herein, porous carbons are fabricated by using tetra-alkali metal pyromellitic acid salts as precursors through a carbonization/self-activation procedure for enhancing zinc ion storage. The optimized rubidium-activated porous carbon (RbPC) is verified to hold immense surface area, suitable porosity structure, massive lattice defects, and luxuriant oxygen functional groups. These structural and compositional merits endow RbPC with the promoted zinc ion storage capability and more matchable kinetics and capacity with a Zn anode. Consequently, RbPC-based ZIC delivers a high specific energy of 178.2 W h kg-1 and a peak power density of 72.3 kW kg-1. A systematic ex situ characterization analysis coupled with in situ electrochemical quartz crystal microbalance tests reveal that the preeminent zinc ion storage properties are ascribed to the synergistic effect of the dual-ion adsorption and reversible chemical adsorption of RbPC. This work provides an efficient strategy to the rational design and construction of high-performance electrodes for ZICs and furthers the fundamental understanding of their charge storage mechanisms or extends the understanding toward other electrochemical energy storage devices.

4.
Int J Biol Macromol ; 178: 381-393, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662414

RESUMO

Alzheimer's disease is a neurodegenerative disease which severely impacts the health of the elderly. Current treatments are only able to alleviate symptoms, but not prevent or cure the disease. The neurofibrillary tangles formed by tau protein aggregation are one of the defining characteristics of Alzheimer's disease, so tau protein has become a key target for the drug design. In this study, we show that fisetin, a plant-derived polyphenol compound, can inhibit aggregation of the tau fragment, K18, and can disaggregate tau K18 filaments in vitro. Meanwhile it is able to prevent the formation of tau aggregates in cells. Both experimental and computational studies indicate that fisetin could directly interact with tau K18 protein. The binding is mainly created by hydrogen bond and van der Waal force, prevents the formation of ß-strands at the two hexapeptide motifs, and does not perturb the secondary structure or the tubulin binding ability of tau protein. In summary, fisetin might be a candidate for further development as a potential preventive or therapeutic drug for Alzheimer's disease.


Assuntos
Flavonóis/química , Agregados Proteicos/efeitos dos fármacos , Proteínas tau/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Motivos de Aminoácidos , Flavonóis/farmacologia , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas tau/metabolismo
5.
Nat Commun ; 11(1): 5196, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060592

RESUMO

Pericytes play essential roles in blood-brain barrier (BBB) integrity and dysfunction or degeneration of pericytes is implicated in a set of neurological disorders although the underlying mechanism remains largely unknown. However, the scarcity of material sources hinders the application of BBB models in vitro for pathophysiological studies. Additionally, whether pericytes can be used to treat neurological disorders remains to be elucidated. Here, we generate pericyte-like cells (PCs) from human pluripotent stem cells (hPSCs) through the intermediate stage of the cranial neural crest (CNC) and reveal that the cranial neural crest-derived pericyte-like cells (hPSC-CNC PCs) express typical pericyte markers including PDGFRß, CD146, NG2, CD13, Caldesmon, and Vimentin, and display distinct contractile properties, vasculogenic potential and endothelial barrier function. More importantly, when transplanted into a murine model of transient middle cerebral artery occlusion (tMCAO) with BBB disruption, hPSC-CNC PCs efficiently promote neurological functional recovery in tMCAO mice by reconstructing the BBB integrity and preventing of neuronal apoptosis. Our results indicate that hPSC-CNC PCs may represent an ideal cell source for the treatment of BBB dysfunction-related disorders and help to model the human BBB in vitro for the study of the pathogenesis of such neurological diseases.


Assuntos
Isquemia Encefálica/metabolismo , Pericitos/metabolismo , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Isquemia Encefálica/patologia , Diferenciação Celular/genética , Infarto da Artéria Cerebral Média , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Crista Neural/metabolismo , Células-Tronco Pluripotentes/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Recuperação de Função Fisiológica/genética , Acidente Vascular Cerebral/patologia , Transcriptoma
6.
ACS Chem Neurosci ; 9(7): 1560-1565, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29714059

RESUMO

Abnormal accumulation of tau protein into oligomers contributes to neuronal dysfunction. Reduction of tau level is potentially able to prevent its accumulation. Here we uncover a critical role of the free thiol at Cys-322 in determining tau stability. We found that the application of thiol-blocking agents like NEM or MMTS blocks this thiol, by which it destabilizes tau protein and prevents its oligomer formation. Furthermore, we identified a tau-interacting protein, selenoprotein W, which attenuates tau accumulation by forming disulfide linkage between SelW Cys-37 and tau Cys-322. These findings provide a promising strategy to prevent tau accumulation and oligomer formation.


Assuntos
Proteínas tau/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Apoptose , Encéfalo/metabolismo , Cisteína/metabolismo , Escherichia coli , Células HEK293 , Humanos , Peróxido de Hidrogênio , Camundongos Transgênicos , Agregação Patológica de Proteínas/tratamento farmacológico , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Proteínas Recombinantes/química , Selenoproteína W/metabolismo , Compostos de Sulfidrila/antagonistas & inibidores , Compostos de Sulfidrila/metabolismo , Proteínas tau/genética
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