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1.
ACS Nano ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950148

RESUMEN

Prevailing over the bottleneck of von Neumann computing has been significant attention due to the inevitableness of proceeding through enormous data volumes in current digital technologies. Inspired by the human brain's operational principle, the artificial synapse of neuromorphic computing has been explored as an emerging solution. Especially, the optoelectronic synapse is of growing interest as vision is an essential source of information in which dealing with optical stimuli is vital. Herein, flexible optoelectronic synaptic devices composed of centimeter-scale tellurium dioxide (TeO2) films detecting and exhibiting synaptic characteristics to broadband wavelengths are presented. The TeO2-based flexible devices demonstrate a comprehensive set of emulating basic optoelectronic synaptic characteristics; i.e., excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), conversion of short-term to long-term memory, and learning/forgetting. Furthermore, they feature linear and symmetric conductance synaptic weight updates at various wavelengths, which are applicable to broadband neuromorphic computations. Based on this large set of synaptic attributes, a variety of applications such as logistic functions or deep learning and image recognition as well as learning simulations are demonstrated. This work proposes a significant milestone of wafer-scale metal oxide semiconductor-based artificial synapses solely utilizing their optoelectronic features and mechanical flexibility, which is attractive toward scaled-up neuromorphic architectures.

2.
Polymers (Basel) ; 15(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36616592

RESUMEN

Microplastics have become a ubiquitous contaminant in the environment. The present study focuses on the identification, characterization, and quantification techniques for tracking microplastics. Due to their unique compositional structure, unambiguous identification of individual polymers in various plastic samples, usually comprised of mixtures of individual polymers, remains a challenge. Therefore, there is limited research on the pyrolysis characterization of mixed samples. In this study, two analytical methods, TG-FTIR and TED-GC-MS combined with thermogravimetric analysis were used to evaluate the thermal-degradation process of individual and mixed samples of polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). The primary interaction was the volatilization of terephthalic acid bound to chlorine molecules. The reduction of vinyl-ester functional groups and aromatic hydrocarbon intermediates related to olefin branching was confirmed. Char formation was increased, due to aromatic compounds from PET and PVC. All of the polymers used in the study may be underestimated in quantity, due to combined volatilizations during pyrolysis. TG-FTIR and TED-GC-MS showed forceful advantages in identifying mixed microplastics through different discrimination mechanisms. The study provides deep insight into pyrolysis behaviors and the interactions of mixed polymers, and the obtained results can help better comprehend the complex pyrolysis process.

3.
ACS Nano ; 16(12): 20057-20074, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36373736

RESUMEN

Although conventional topical approaches for treating psoriasis have been offered as an alternative, there are still unmet medical needs such as low skin-penetrating efficacy and off-target adverse effects. A hyaluronic acid nanoparticle (HA-NP) formed by self-assembly of HA-hydrophobic moiety conjugates has been broadly studied as a nanocarrier for long-term and target-specific delivery of drugs, owing to their excellent physicochemical and biological characteristics. Here, we identify HA-NPs as topical therapeutics for treating psoriasis using in vivo skin penetration studies and psoriasis animal models. Transcutaneously administered HA-NPs were found to be accumulated and associated with pro-inflammatory macrophages in the inflamed dermis of a psoriasis mouse model. Importantly, HA-NP exerted potent therapeutic efficacy against psoriasis-like skin dermatitis in a size-dependent manner by suppressing innate immune responses and restoring skin barrier function without overt toxicity signs. The therapeutic efficacy of HA-NPs on psoriasis-like skin dermatitis was due to the outermost hydrophilic HA shell layer of HA-NPs, independent of the molecular weight of HA and hydrophobic moiety, and comparable with that of other conventional psoriasis therapeutics widely used in the clinical settings. Overall, HA-NPs have the potential as a topical nanomedicine for treating psoriasis effectively and safely.


Asunto(s)
Dermatitis , Nanopartículas , Psoriasis , Ratones , Animales , Ácido Hialurónico/química , Psoriasis/tratamiento farmacológico , Piel , Nanopartículas/química
4.
J Int Med Res ; 50(4): 3000605221093308, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35481419

RESUMEN

OBJECTIVE: To investigate the effects of piperlongumine (PL) and vitamin C (VC) on signal transducer and activator of transcription 3 (STAT3) signalling in gastric cancer cell lines. METHODS: In vivo tumour xenograft anticancer assays were undertaken to confirm the anticancer activity of PL. Cell viability, flow cytometry and Western blot assays were undertaken to evaluate the anticancer effects of PL, VC and combinations of PL and VC in AGS and KATO III cells. RESULTS: Both PL and VC induced apoptosis and inhibited cell proliferation in AGS and KATO III cells. These effects were dependent on reactive oxygen species (ROS). PL effectively suppressed STAT3 activation while VC caused abnormal activation of STAT3. The combination of PL and VC exhibited a stronger apoptotic effect compared with either agent alone. PL reversed the abnormal activation of STAT3 by VC, which could be a key to their synergistic effect. CONCLUSIONS: PL combined with VC exhibited a stronger anticancer effect by regulating the ROS-STAT3 pathway, suggesting that this combination might be a potential adjuvant therapy for gastric cancer.


Asunto(s)
Factor de Transcripción STAT3 , Neoplasias Gástricas , Ácido Ascórbico/farmacología , Ácido Ascórbico/uso terapéutico , Línea Celular Tumoral , Quimioterapia Adyuvante , Dioxolanos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción STAT3/metabolismo , Neoplasias Gástricas/patología
5.
Animals (Basel) ; 11(4)2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33921530

RESUMEN

We performed an 8-week feeding trial to evaluate dietary soluble extract hydrolysates from fishery by-products, such as shrimp soluble extract (SSE) with or without inosine monophosphate (IMP), tilapia soluble extract (TSE) and squid soluble extract (SQSE), in juvenile Nile tilapia. A diet without feed additives was used as the control diet (CON); and five other experimental diets were formulated with 2% soluble extracts consisting of 100% SSE, 98% SSE + 2% IMP (SSEP2), 96% SSE + 4% IMP (SSEP4), 100% SQSE and 100% TSE. The diets were fed to 4.9 ± 0.07 g (mean ± SD) juvenile Nile tilapia in triplicate groups. The weight gain and specific growth rates of fish fed the SSE, SSEP2 and SSEP4 diets were significantly higher than those of fish fed the CON and SQSE diets. The superoxide dismutase activity levels of fish fed the SSE and SSEP4 diets were significantly higher than those of fish fed the CON, SSEP2, SQSE and TSE diets. Myeloperoxidase activity levels of fish fed the SSE and SSEP4 diets were significantly higher than those of fish fed the CON, SSEP2 and SQSE diets. Lysozyme activity levels of fish fed the SSEP4 and SQSE diets were significantly higher than those of fish fed the SSE and SSEP2 diets. Feed efficiency, protein efficiency ratio, survival rate, whole body proximate composition and hematological parameters were not significantly different among the groups. After ten days of challenge = against Aeromonas hydrophila, the cumulative survival rate of fish fed the SSE diet was significantly higher than those of fish fed the CON, SQSE and TSE diets. In conclusion, dietary shrimp soluble extract could improve the growth performance, non-specific immune responses and disease resistance in juvenile Nile tilapia, and inosine monophosphate did not add further benefits to this ingredient.

6.
Healthc Inform Res ; 24(1): 79-85, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29503756

RESUMEN

OBJECTIVES: Customer discovery (CD) is a method to determine if there are actual customers for a product/service and what they would want before actually developing the product/service. This concept, however, is rather new to health information technology (IT) systems. Therefore, the aim of this paper was to demonstrate how to use the CD method in developing a comprehensive health IT service for patients with knee/leg pain. METHODS: We participated in a 6-week I-Corps program to perform CD, in which we interviewed 55 people in person, by phone, or by video conference within 6 weeks: 4 weeks in the United States and 2 weeks in Korea. The interviewees included orthopedic doctors, physical therapists, physical trainers, physicians, researchers, pharmacists, vendors, and patients. By analyzing the interview data, the aim was to revise our business model accordingly. RESULTS: Using the CD approach enabled us to understand the customer segments and identify value propositions. We concluded that a facilitating tele-rehabilitation system is needed the most and that the most suitable customer segment is early stage arthritis patients. We identified a new design concept for the customer segment. Furthermore, CD is required to identify value propositions in detail. CONCLUSIONS: CD is crucial to determine a more desirable direction in developing health IT systems, and it can be a powerful tool to increase the potential for successful commercialization in the health IT field.

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