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1.
Macromol Rapid Commun ; : e2400336, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38924226

RESUMEN

Poly(ethylene glycol) (PEG) or oligo (ethylene glycol) (OEG) grafted anion exchange membranes (AEMs) exhibit improved ionic conductivity, high alkaline stability, and subsequent boosted AEM fuel cell performance, but too much PEG/OEG side chains may can result in a reduction in the ion exchange capacity (IEC), which can have adverse effects on ion transport. Here, a series of partially PEG-grafted poly(terphenyl piperidinium) with different side chain length are synthesized using simple postpolymerization modification to produce AEMs with balanced properties. The polar and flexible PEG side chains are responsible for the controlled water uptake and swelling, superior hydroxide conductivity (122 mS cm-1 at 80 °C with an IEC of 1.99 mmol g-1), and enhanced alkaline stability compared to the reference sample without PEG grafts (PTP). More importantly, the performance of AEM fuel cell (AEMFC) with the membrane containing partial PEG side chains surpasses that with PTP membrane, demonstrating a highest peak power density of 1110 mW cm-2 at 80 °C under optimized conditions. This work provides a novel approach to the fabrication of high-performance AEM materials with balanced properties for alkaline fuel cell application.

2.
Polymers (Basel) ; 15(12)2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37376285

RESUMEN

The application of flexible indium tin oxide (ITO-free) electrochromic devices has steadily attracted widespread attention in wearable devices. Recently, silver nanowire/poly(dimethylsiloxane) (AgNW/PDMS)-based stretchable conductive films have raised great interest as ITO-free substrate for flexible electrochromic devices. However, it is still difficult to achieve high transparency with low resistance due to the weak binding force between AgNW and PDMS with low surface energy because of the possibility of detaching and sliding occurring at the interface. Herein, we propose a method to pattern the pre-cured PDMS (PT-PDMS) by stainless steel film as a template through constructed micron grooves and embedded structure, to prepare a stretchable AgNW/PT-PDMS electrode with high transparency and high conductivity. The stretchable AgNW/PT-PDMS electrode can be stretched (5000 cycles), twisted, and surface friction (3M tape for 500 cycles) without significant loss of conductivity (ΔR/R ≈ 16% and 27%). In addition, with the increase of stretch (stretching to 10-80%), the AgNW/PT-PDMS electrode transmittance increased, and the conductivity increased at first and then decreased. It is possible that the AgNWs in the micron grooves are spread during PDMS stretching, resulting in a larger spreading area and higher transmittance of the AgNWs film; at the same time, the nanowires between the grooves come into contact, thus increasing conductivity. An electrochromic electrode constructed with the stretchable AgNW/PT-PDMS exhibited excellent electrochromic behavior (transmittance contrast from ~61% to ~57%) even after 10,000 bending cycles or 500 stretching cycles, indicating high stability and mechanical robustness. Notably, this method of preparing transparent stretch electrodes based on patterned PDMS provides a promising solution for developing electronic devices with unique structures and high performance.

3.
Front Plant Sci ; 13: 863211, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35665192

RESUMEN

Nitrogen (N) is the most limiting nutrient for turfgrass growth. Few tools or soil tests exist to help managers guide N fertilizer decisions. Turf growth prediction models have the potential to be useful, but the lone turfgrass growth prediction model only takes into account temperature, limiting its accuracy. This study investigated the ability of a machine learning (ML)-based turf growth model using the random forest (RF) algorithm (ML-RF model) to improve creeping bentgrass (Agrostis stolonifera) putting green management by estimating short-term clipping yield. This method was compared against three alternative N application strategies including (1) PACE Turf growth potential (GP) model, (2) an experience-based method for applying N fertilizer (experience-based method), and (3) the experience-based method guided by a vegetative index, normalized difference red edge (NDRE)-based method. The ML-RF model was built based on a set of variables including 7-day weather, evapotranspiration (ET), traffic intensity, soil moisture content, N fertilization rate, NDRE, and root zone type. The field experiment was conducted on two sand-based research greens in 2020 and 2021. The cumulative applied N fertilizer was 281 kg ha-1 for the PACE Turf GP model, 190 kg ha-1 for the experience-based method, 140 kg ha-1 for the ML-RF model, and around 75 kg ha-1 NDRE-based method. ML-RF model and NDRE-based method were able to provide customized N fertilization recommendations on different root zones. The methods resulted in different mean turfgrass qualities and NDRE. From highest to lowest, they were PACE Turf GP model, experience-based, ML-RF model, and NDRE-based method, and the first three methods produced turfgrass quality over 7 (on a scale from 1 to 9) and NDRE value over 0.30. N fertilization guided by the ML-RF model resulted in a moderate amount of fertilizer applied and acceptable turfgrass performance characteristics. This application strategy is based on the N cycle and has the potential to assist turfgrass managers in making N fertilization decisions for creeping bentgrass putting greens.

4.
Pak J Pharm Sci ; 34(5(Special)): 2035-2040, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34862870

RESUMEN

This study aimed to investigate the effect of the therapy of amiodarone combined with atorvastatin on cardiac function of patients with acute myocardial infarction after percutaneous coronary intervention (PCI). A total of 90 patients with acute myocardial infarction who underwent PCI in the tertiary care hospital from January 2019 to January 2020 were selected as the subjects and randomly assigned into the control group and the study group, with 45 cases in each group. All the subjects had undergone PCI. The control group received amiodarone while those the study group received atorvastatin additionally. Comparison was done on the clinical efficacy, cardiac function, myocardial injury indicator and inflammatory factor between the two groups. The overall response rate (ORR) in the study group was significantly higher than that in the control group (P<0.05); patients in the study group had markedly better cardiac function compared with those in the control group (P<0.001); patients in the study group had considerably lower creatine kinase (CK) index, creatine kinase-MB (CK-MB) index, tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) as opposed to those in the control group (P<0.001). It was observed that the therapy of amiodarone combined with atorvastatin could effectively improve the clinical indicators and cardiac function of patients with acute myocardial infarction after PCI. It is effective and worthy of wide promotion and application.


Asunto(s)
Amiodarona/uso terapéutico , Atorvastatina/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Intervención Coronaria Percutánea , Amiodarona/efectos adversos , Atorvastatina/efectos adversos , Fármacos Cardiovasculares/efectos adversos , Estudios de Casos y Controles , China , Forma MB de la Creatina-Quinasa/sangre , Quimioterapia Combinada , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Mediadores de Inflamación/sangre , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/fisiopatología , Intervención Coronaria Percutánea/efectos adversos , Distribución Aleatoria , Factores de Tiempo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/sangre
5.
Front Plant Sci ; 12: 749854, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34804091

RESUMEN

Nitrogen is the most limiting nutrient for turfgrass growth. Instead of pursuing the maximum yield, most turfgrass managers use nitrogen (N) to maintain a sub-maximal growth rate. Few tools or soil tests exist to help managers guide N fertilizer decisions. Turf growth prediction models have the potential to be useful, but the currently existing turf growth prediction model only takes temperature into account, limiting its accuracy. This study developed machine-learning-based turf growth models using the random forest (RF) algorithm to estimate short-term turfgrass clipping yield. To build the RF model, a large set of variables were extracted as predictors including the 7-day weather, traffic intensity, soil moisture content, N fertilization rate, and the normalized difference red edge (NDRE) vegetation index. In this study, the data were collected from two putting greens where the turfgrass received 0 to 1,800 round/week traffic rates, various irrigation rates to maintain the soil moisture content between 9 and 29%, and N fertilization rates of 0 to 17.5 kg ha-1 applied biweekly. The RF model agreed with the actual clipping yield collected from the experimental results. The temperature and relative humidity were the most important weather factors. Including NDRE improved the prediction accuracy of the model. The highest coefficient of determination (R2) of the RF model was 0.64 for the training dataset and was 0.47 for the testing data set upon the evaluation of the model. This represented a large improvement over the existing growth prediction model (R 2 = 0.01). However, the machine-learning models created were not able to accurately predict the clipping production at other locations. Individual golf courses can create customized growth prediction models using clipping volume to eliminate the deviation caused by temporal and spatial variability. Overall, this study demonstrated the feasibility of creating machine-learning-based yield prediction models that may be able to guide N fertilization decisions on golf course putting greens and presumably other turfgrass areas.

6.
Front Plant Sci ; 12: 829508, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35126438

RESUMEN

[This corrects the article DOI: 10.3389/fpls.2021.749854.].

7.
Cell Cycle ; 19(10): 1158-1171, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32308102

RESUMEN

Objective: Long noncoding RNAs (lncRNAs) have already been proposed to function in Parkinson's disease (PD). However, the role of lncRNA BACE1-AS in PD has never been discussed. This study aims to examine the mechanism of BACE1-AS on oxidative stress injury of dopaminergic neurons in PD rats.Methods: Rat models of PD were established through the injection of 6-hydroxydopamine. The rotation of rats was induced by intraperitoneal injection of apomorphine, and number of rotations per minute was detected. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), glutamic acid (Glu), dopamine (DA), tyrosine hydroxylase (TH), α-synuclein and inducible nitric oxide synthase (iNOS) in the substantia nigra of rats in each group were detected. Apoptosis and pathological changes in the substantia nigra were also observed. BACE1-AS, miR-34b-5p, BACE1, Bax and Bcl-2 expression in the substantia nigra were detected. The binding of BACE1-AS and miR-34b-5p and the targeting relationship of miR-34b-5p and BACE1 were further determined.Results: Downregulated BACE1-AS reduced iNOS, α-synuclein and Glu levels and elevated DA and TH levels in the substantia nigra of PD rats. Downregulated BACE1-AS repressed apoptosis and oxidative stress injury in the substantia nigra neurons of PD rats. BACE1-AS specifically bound to miR-34b-5p. BACE1 was a direct target gene of miR-34b-5p.Conclusion: Collectively, our study reveals that downregulation of lncRNA BACE1-AS inhibits iNOS activation in the substantial nigra and improve oxidative stress injury in PD rats by upregulating miR-34b-5p and downregulating BACE1.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/genética , Ácido Aspártico Endopeptidasas/genética , Regulación hacia Abajo/genética , Hidroxidopaminas/administración & dosificación , MicroARNs/metabolismo , Estrés Oxidativo/efectos de los fármacos , Enfermedad de Parkinson Secundaria/metabolismo , ARN sin Sentido/genética , ARN Largo no Codificante/genética , Regulación hacia Arriba/genética , Animales , Apoptosis/genética , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Vectores Genéticos/administración & dosificación , Hidroxidopaminas/efectos adversos , Masculino , Óxido Nítrico Sintasa de Tipo II/metabolismo , Enfermedad de Parkinson Secundaria/inducido químicamente , Ratas , Transducción de Señal/genética , Sustancia Negra/metabolismo
8.
Med Sci Monit ; 25: 6034-6042, 2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31407674

RESUMEN

BACKGROUND This study aimed to determine the association between CD4-positive T-helper (Th) cell subsets, T-helper 1 (Th1) and T-helper 2 (Th2) in patients with acute myocardial infarction (AMI) and the severity of coronary artery disease (CAD) determined by coronary artery angiography. MATERIAL AND METHODS Three groups of patients with AMI who underwent coronary angiography and percutaneous coronary intervention (PCI) included patients with stable CAD (n=35), ST-segment elevation myocardial infarction (STEMI) (n=30), and non-STEMI (NSTEMI) (n=35), and controls (n=33). Measurement of high-sensitivity cardiac troponin T (hs-cTnT) was performed. The numbers of circulating CD4-positive Th1 and Th2 cells were measured using flow cytometry. Plasma levels of interferon-γ (IFN-γ) and interleukin-4 (IL-4) were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS An increase in the Th1 lymphocyte population was associated with more CAD, and an increased Th1/Th2 ratio was found in patients with NSTEMI and STEMI (controls 7.27±2.98; stable CAD 7.58±2.52; NSTEMI 16.62±2.74; and STEMI 22.32±7.35) (P<0.001). The proportion of Th1 cells and the Th1/Th2 ratio increased as the number of affected arteries, the degree of stenosis, and the lesion length increased. At a median follow-up of 18.2 months, patients with CAD and an increased Th1/Th2 ratio had a significant increase in adverse cardiac events compared with patients with a reduced Th1/Th2 ratio (log-rank, P=0.042). CONCLUSIONS An increased ratio of circulating Th1 to Th2 cells in patients with AMI was associated with the severity of CAD determined by angiography.


Asunto(s)
Enfermedad de la Arteria Coronaria/inmunología , Infarto del Miocardio/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Anciano , China , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/sangre , Vasos Coronarios/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Intervención Coronaria Percutánea , Estudios Prospectivos , Infarto del Miocardio con Elevación del ST , Índice de Severidad de la Enfermedad , Células TH1/inmunología , Células Th2/inmunología
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