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1.
ACS Nano ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950148

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-36616592

RESUMO

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.
J Food Biochem ; 43(7): e12862, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31353698

RESUMO

In this study, a novel method of continuous coupling of immobilized enzymatic hydrolysis reactor and membrane separation (CIEH-MS) was used to isolate the immunomodulatory peptides from type II collagen (CII) in chick sternal cartilage. The immobilized neutral protease was successfully prepared with an activity of 400.5 U/g. The CIEH-MS system loaded with immobilized neutral protease had high operational stability with enzyme decay constant of 0.0077 and half-life of 89.61 hr. Using a CIEH-MS system, the immunomodulatory peptides were obtained with lymphocyte proliferation of 66.23%, peptide yield of 23.43%, degree of hydrolysis (DH) of 22.41%, and permeate flux of 6.17 L/m2 h. The peptide fractions were further purified and the P3-2-4 fraction (RGQLGPM) with 760.4 Da molecular weights exhibited the highest lymphocyte proliferation activity (85.54%) and binding ability to human leukocyte antigen-DRB1 (HLA-DRB1) molecules (133.2 ng/ml). The results demonstrated that CIEH-MS system is an effective way to obtain immunomodulatory peptides from CII. PRACTICAL APPLICATIONS: Chick sternal cartilage is one of the by-products of meat processing, and it is often discarded as waste or used for low-value purposes. CII is the most abundant collagen in chick sternal cartilage, and recently studies have demonstrated that CII peptides possess the ability to induce immunologic tolerance for the treatment of chronic disease. In order to find potential applications for this by-product, immunomodulatory peptides from CII hydrolysates in chick sternal cartilage were isolated using a novel CIEH-MS system. The result showed that CII peptides exhibited a high immunomodulatory activity, and had a potential application in functional foods and medical fields.


Assuntos
Colágeno Tipo II/imunologia , Fatores Imunológicos/isolamento & purificação , Animais , Galinhas , Colágeno Tipo II/análise , Colágeno Tipo II/química , Ensaios Enzimáticos/métodos , Enzimas Imobilizadas/isolamento & purificação , Osteocondrodisplasias/imunologia , Peptídeos/isolamento & purificação
4.
Oncol Lett ; 13(3): 1767-1774, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28454322

RESUMO

BIX01294 (Bix) is known to be a euchromatic histone-lysine N-methyltransferase 2 inhibitor and treatment with Bix suppresses cancer cell survival and proliferation. In the present study, it was observed that sequential treatment with low-dose Bix notably increases glioblastoma cell migration and metastasis. It was demonstrated that U251 cells sequentially treated with low-dose Bix exhibited induced characteristic changes in critical epithelial-mesenchymal transition (EMT) markers, including E-cadherin, N-cadherin, ß-catenin and zinc finger protein SNAI2. Notably, sequential treatment with Bix also increased the expression of cancer stem cell-associated markers, including sex determining region Y-box 2, octamer-binding transcription factor 4 and cluster of differentiation 133. Neurosphere formation was significantly enhanced in cells sequentially treated with Bix, compared with control cells (control: P=0.011; single treatment of Bix, P=0.045). The results of the present study suggest that accumulation of low-dose Bix enhanced the migration and metastatic potential of glioblastoma cells by regulating EMT-associated gene expression, which may be the cause of the altered properties of glioblastoma stem cells.

5.
J Clin Nurs ; 21(13-14): 1840-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22672452

RESUMO

AIMS AND OBJECTIVES: To investigate how many critically ill patients developed deep vein thrombosis (DVT) during their admission to intensive care units (ICU) and to compare the characteristics of patients with and without deep vein thrombosis. BACKGROUND: Critically ill patients are a high-risk group for deep vein thrombosis because they typically have multiple risk factors, such as prolonged immobility, mechanical ventilation and old age. DESIGN: A prospective observational study was employed. METHODS: The subjects were 90 patients who were older than 18 years of age, who were admitted to an intensive care unit for more than five days and were not provided any prophylactic measures. Data were collected at a university hospital for five months. A duplex scan was performed on day 2.4 on average and repeated between days 5-7 to diagnose deep vein thrombosis. The iliac, femoral, popliteal and tibial veins were examined by compression and colour Doppler methods of the duplex scan by one technician. RESULTS: Age, gender and body mass index were significant factors for deep vein thrombosis development (p < 0.05). Ten patients (11.1%) developed deep vein thrombosis during their stay in the intensive care units. CONCLUSIONS: The incidence was lower than in Western studies in which patients were not provided prophylaxis, but may increase with an extended observation period as in previous studies. RELEVANCE TO CLINICAL PRACTICE: The results of this study could allow ICU nurses to recognise the DVT incidence in critically ill patients. This result could lead to more active prevention and monitoring of DVT by ICU nurses, especially for high-risk patients, such as older or obese patients.


Assuntos
Estado Terminal , Perna (Membro)/irrigação sanguínea , Trombose Venosa/epidemiologia , Adulto , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
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