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1.
Langmuir ; 40(11): 5557-5570, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38465803

RESUMEN

Contact electrification (CE) is a common physical process by which triboelectric charges are generated through the mutual contact between two objects. Despite the ongoing debates on CE's mechanism, recent advancements in technology have elucidated the primary role of electron transfer in most CE processes. This discovery leads to the spawning of an emerging field, known as contact-electro-catalysis (CEC), which utilizes the electron transfer phenomenon during CE to initiate CEC. In this work, we provide the first comprehensive review of the recent progress of the solid-liquid interface-mediated CEC process, including its working principles, relationship with surface science, recent breakthroughs in applications, and future challenges. We aim to provide fundamental guidance for researchers to understand the reaction mechanism of the CEC process and to propose potential pathways to enhance CEC efficiency from a surface and interfacial science perspective. Later, recent application scenarios using the novel CEC techniques are summarized, including wastewater treatment, efficient generation of hydrogen peroxide (H2O2), lithium-ion battery recycling, and CO2 reduction. In general, CEC technology has opened a new avenue for catalysis, effectively expanding the range of catalyst options and holding promise as a solution to a variety of complex catalytic challenges in the future.

2.
Langmuir ; 39(45): 15950-15961, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37909422

RESUMEN

SiZrOC aerogels were synthesized through the pyrolysis of the zirconium source-doped SiOC system using zirconyl chloride octahydrate (ZrOCl2·8H2O) at temperatures ranging from 900 to 1300 °C. This study investigates the microstructure evolution and phase separation of SiOC and SiZrOC aerogels during the pyrolysis process. Upon pyrolysis, both aerogels exhibited a Si-O-C structure with a high thermal stability. The introduction of zirconium elements significantly enhanced the pore volume (3.20 cm3/g) and porosity (96.0%) and reduced the thermal conductivity (0.023 W·m-1·K-1) of the organic-inorganic precursor aerogel. Moreover, the three-dimensional pore structure was retained even under high-temperature pyrolysis conditions. SiZrOC-1100 displayed a high specific surface area of 273.52 m2/g, a high pore volume of 1.70 cm3/g, and a low thermal conductivity of 0.033 W·m-1·K-1. At high temperatures, the SiZrOC phase transformation produces tetragonal ZrO2, which inhibits the graphitization process of free carbon and the growth of SiC grains. Furthermore, the phase separation process of the SiOxCy matrix structure generated oxygen-rich SiOxC4-x units, while carbon-rich SiOxC4-x units were negligible below a pyrolysis temperature of 1200 °C. Between 900 and 1200 °C, SiZrOC is composed of amorphous SiOC, amorphous ZrO2, microcrystalline t-ZrO2, and free carbon phase. These findings provide valuable insights into the preparation of high-performance SiOC aerogels.

3.
Sensors (Basel) ; 22(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36502158

RESUMEN

Accurately forecasting the demand of urban online car-hailing is of great significance to improving operation efficiency, reducing traffic congestion and energy consumption. This paper takes 265-day order data from the Hefei urban online car-hailing platform from 2019 to 2021 as an example, and divides each day into 48 time units (30 min per unit) to form a data set. Taking the minimum average absolute error as the optimization objective, the historical data sets are classified, and the values of the state vector T and the parameter K of the K-nearest neighbor model are optimized, which solves the problem of prediction error caused by fixed values of T or K in traditional model. The conclusion shows that the forecasting accuracy of the K-nearest neighbor model can reach 93.62%, which is much higher than the exponential smoothing model (81.65%), KNN1 model (84.02%) and is similar to LSTM model (91.04%), meaning that it can adapt to the urban online car-hailing system and be valuable in terms of its potential application.


Asunto(s)
Análisis por Conglomerados , Predicción
4.
PLoS One ; 17(7): e0271615, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35839234

RESUMEN

A fault detection method using skeleton extraction based on orientation field consistency is proposed to improve the efficiency of fault detection, reduce the influence of transverse nonstructural factors on fault detection, and realize automatic fault extraction. In fingerprint image processing, the consistency of the orientation field reaches a maximum value when all orientations are parallel and takes a smaller value when not all orientations are parallel. The orientation field ceases to be parallel in the presence of a stratigraphic discontinuity, and the consistency of the orientation field in the corresponding region is lower than that in parallel regions. This characteristic can be exploited to extract discontinuous regions from seismic data. Then, binarization and closing operations are used to extract fault areas and increase fault continuity. Finally, a skeleton extraction method based on extracting the longitudinal center point is used to identify the fault lines. Compared with the classical ant tracking method, the proposed method requires the adjustment of fewer parameters, thus simplifying fault identification process to a certain extent. Moreover, the proposed method effectively suppresses transverse discontinuities, highlights the longitudinal fault characteristics, and strengthens fault continuity.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Esqueleto
5.
Materials (Basel) ; 15(12)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35744324

RESUMEN

In order to evaluate the homogeneity of asphalt mixture quantitatively, the distribution characteristic of internal phases of asphalt mixture were identified based on digital image processing technique and stereology theory, and the homogeneity coefficient (i.e., K) was proposed. At the same time, the trend of variation and reliability of homogeneity of asphalt mixture were analyzed by changing the nominal maximum aggregate size, aggregate gradation and asphalt content. The results suggest that the homogeneity of asphalt mixture could be comprehensively described using DIP technique combined with stereology theory. The smaller the K, the better the distribution homogeneity of the asphalt mixture. An improvement in the homogeneity of an asphalt mixture is achieved with the decrease of the nominal maximum aggregate size and a finer aggregate gradation. The asphalt content corresponding to the optimal homogeneity of the internal structure of asphalt mixture specimen is the optimum asphalt content. According to the experimental study, the suggested values of the homogeneity coefficient were given, which provides theoretical support to control the construction quality of the hot mixture asphalt.

6.
Neurol Res ; 44(8): 684-691, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35130819

RESUMEN

BACKGROUND: Few studies have examined the association between hemoglobin (Hb) levels and early neurological changes following acute ischemic stroke (AIS). The present research investigated whether higher or lower Hb level on admission was associated with early neurological deterioration (END) in AIS patients. Furthermore, we evaluated the predictive effect of Hb concentration on stable or improving outcome. METHODS: In this prospective cohort study, a total of 1330 patients admitted within 24 hours after AIS onset were finally involved in the analysis. We classified participants into four groups according to baseline Hb levels: ≤120, 121-140, 141-160, and >160 g/L. The risk of END was accessed by means of logistic regression analysis, and tendency of improvement and stability by multinomial logit analysis. We further evaluated the pattern and magnitude of association of Hb as a continuous variable and END by multivariate logistic regression analysis of restricted cubic spline. RESULTS: Compared with the reference group, hemoglobin >160 g/L was associated with END (OR, 95%CI; 2.149, 1.314-3.512) and severe END (OR, 95% CI as 2.317, 1.351-3.976 and 2.810,1.589-4.968, respectively). Comparatively, higher Hb level also independently predicted improving (OR, 95% CI; 0.322, 0.170-0.609) and stable (OR, 95% CI; 0.371, 0.205-0.673) outcome. Similar results were found when restricted to anterior circulation ischemic stroke after adjustment of variables including large vessel disease. CONCLUSIONS: We concluded that patients with higher baseline Hb level are at significantly higher risk for END, and less likely to reach stable or improving status at the early stage of stroke.


Asunto(s)
Isquemia Encefálica , Hemoglobinas , Accidente Cerebrovascular Isquémico , Isquemia Encefálica/complicaciones , Hemoglobinas/análisis , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Valor Predictivo de las Pruebas , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo
7.
PLoS One ; 15(9): e0238359, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32986731

RESUMEN

Based on the characteristics of expressway driving behavior, a punishment avoidance variable is introduced in this study to modify the theory of planned behavior (TPB), and the analysis model of expressway speeding behavior is improved and verified through survey data. The mechanism of the effects of attitude to behavior, subjective norm, perceived behavioral control, and punishment avoidance on expressway speeding behavior is analyzed. The results show that drivers lack a correct understanding of expressway speeding behavior and that punishment avoidance has a significant effect on expressway speeding behavior. Younger drivers (25-34), men, High income earners, and those who received more penalty points are considered prone to speeding. The study provides valuable contributions to the development of the Chinese version of the expressway speeding analysis model.


Asunto(s)
Aceleración , Conducción de Automóvil/psicología , Conducción de Automóvil/estadística & datos numéricos , Teoría Psicológica , Castigo , Adolescente , Adulto , Anciano , Actitud , China , Humanos , Intención , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sociológicos , Encuestas y Cuestionarios , Adulto Joven
8.
Int J Cardiol ; 130(2): 165-73, 2008 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-18585800

RESUMEN

BACKGROUND: Inflammation and oxidant stress have been suggested to be involved in the structural remodeling in atrial fibrillation (AF), and inducible nitric oxide synthase (iNOS) is associated with inflammation and oxidant stress. To study whether iNOS could contribute to atrial remodeling in AF, we investigated the relationship between inflammation, oxidant stress, nitric oxide (NO) and its synthase, and cardiomyocytic apoptosis in the right atrium in human AF. METHODS: Fifteen patients with permanent AF (PmAF) and 17 patients with sinus rhythm (SR), who underwent mitral valve replacement surgery were investigated. Western blotting and immunohistochemical staining were used to detect the expression of endothelial nitric oxide synthase (eNOS), iNOS and 3-nitrotyrosine (3NT; a biological marker of peroxynitrite) in the right atrium. The occurrence of cardiomyocytic apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). Caspase 3 staining for the activated, cleaved protease was also performed. In addition, concentrations of NO(2)(-)/NO(3)(-) (NO(X)) both in plasma and in the right atrium were measured by a NO(X) Detection Kit. Finally, plasma levels of high-sensitivity C-reactive protein (hs-CRP) were routinely measured. RESULTS AND CONCLUSIONS: Levels of hs-CRP were far more enhanced in patients with PmAF compared to the controls. Plasma levels of NO(X) were significantly lower in PmAF patients than SR patients, but the production of NO(X) in the local right atrium increased obviously. Furthermore, iNOS and 3NT expressions increased dramatically in the right atrium in PmAF patients, whereas the expression of eNOS did not change apparently. In addition, when patients were further divided into a higher hs-CRP group (> or =5 mg/L) and a lower hs-CRP group (<5 mg/L) according to the hs-CRP level, significant upregulation of iNOS was found in the higher hs-CRP group. Apoptosis index and caspase 3 staining were also prominently enhanced in PmAF patients compared with SR patients. More importantly, we demonstrated in this study that a higher expression of 3NT was associated with an increased expression of iNOS/eNOS (r=0.74, P<0.05) and an enhanced apoptosis index (r=0.69, P<0.05). In conclusion, the results presented novel evidence that imbalanced expression of iNOS/eNOS could contribute to protein nitration and cardiomyocyte apoptosis in human AF, in which condition inflammation may be an important participant.


Asunto(s)
Apoptosis/fisiología , Fibrilación Atrial/metabolismo , Miocitos Cardíacos/metabolismo , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Óxido Nítrico/biosíntesis , Fibrilación Atrial/enzimología , Fibrilación Atrial/patología , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Nitratos/metabolismo , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa de Tipo II/fisiología , Estrés Oxidativo/fisiología
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 33(5): 469-72, 2005 May.
Artículo en Chino | MEDLINE | ID: mdl-15932713

RESUMEN

OBJECTIVE: To investigate the effect of cilazapril on endothelial cell function and fibrinolysis system in the canine atrial fibrillation (AF) models. METHODS: All canines were divided into three groups: (1) Control group, without atrial pacing; (2) Atrial pacing group, in which atrial fibrillation was established by rapid atrial pacing at 400 bpm for 6 weeks; (3) Atrial pacing together with cilazapril group, in which cilazapril was given before and after atrial pacing. Nitric oxide (NO) of atrial endocardium was measured with NO-specific microelectrode. The expression of plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (tPA) protein in atrium was determined by Western Blot analysis and immunohistochemical staining. Plasma levels of von Willebrand Factor (vWF), PAI-1 and tPA were analyzed by enzyme-linked immunoadsorbent assay. RESULTS: NO production from atrial endocardium was significantly increased in atrial pacing together with cilazapril group than atrial pacing group [(42.6 +/- 9.9) nmol/L vs (23.4 +/- 5.8) nmol/L, P < 0.05], whereas the plasma levels of vWF were decreased [(75.4 +/- 12.8)% vs (125.9 +/- 20.6)%, P < 0.05]. Compared to controls, the expression of atrium tPA protein in atrial pacing together with cilazapril group was significantly upregulated (4052 +/- 857 vs 1936 +/- 421, P < 0.05) and PAI-1 protein was downregulated (2487 +/- 542 vs 3164 +/- 827, P < 0.05). Cilazapril also significantly increased tPA antigen and decreased PAI-1 antigen in plasma. CONCLUSION: Cilazapril can favorably improve endothelial function and resume the balance of fibrinolysis system in AF, which might be of beneficial to hypercoagulated state in AF.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Fibrilación Atrial/tratamiento farmacológico , Cilazapril/farmacología , Células Endoteliales/efectos de los fármacos , Fibrinólisis/efectos de los fármacos , Animales , Fibrilación Atrial/sangre , Fibrilación Atrial/fisiopatología , Modelos Animales de Enfermedad , Perros , Células Endoteliales/fisiología , Femenino , Inmunohistoquímica , Masculino , Inhibidor 1 de Activador Plasminogénico/análisis , Activador de Tejido Plasminógeno/análisis
10.
Photomed Laser Surg ; 22(6): 477-82, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15684746

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the in vitro effects of He-Ne laser irradiation on some rheological factors of human blood, such as blood viscosity, erythrocyte deformability, and sedimentation rate. BACKGROUND DATA: The intravascular irradiation of low power laser has been applied in pre-clinical and clinical to treat various pathological processes. However, the mechanism is not fully understood so far. Especially the interaction and related mechanism between the laser and blood are unclear. In this work, by measuring the change of the main rheological factors after laser irradiation, the interaction and mechanism were explored. METHODS: A30-mW He-Ne laser was used for irradiation with a 4-5-mm-diameter beam spot on blood samples, with a fluence rate of about 150 mW/cm.(2) The irradiation time was 60 min, so the total dose of irradiation was 540 J/cm.(2) The pathological samples of blood were obtained from patients (volunteers), and each sample was divided into two tubes for irradiation and control. The blood viscosity, erythrocyte deformability, and sedimentation rate were measured after laser irradiation and compared with un-irradiated control. The blood samples with poor erythrocyte deformability were prepared by adding Ca(2+) to the normal erythrocytes of a healthy person for investigating the laser effect on erythrocyte deformability further. RESULTS: Laser irradiation reduced the erythrocyte sedimentation rate of blood samples, which had a hyper-sedimentation rate originally. The blood viscosity of samples in hyper-values was lowered by laser irradiation in all shear rates measured (10-110 S(-1)), with a relative variation of approximately 10%. The deformability of erythrocytes from pathological samples and Ca(2+)-treated samples was improved after laser irradiation. CONCLUSIONS: The positive effects of laser irradiation on improving the rheological properties of blood were demonstrated in vitro.


Asunto(s)
Viscosidad Sanguínea/efectos de la radiación , Deformación Eritrocítica/efectos de la radiación , Hemorreología/efectos de la radiación , Rayos Láser , Sedimentación Sanguínea , Helio , Hematócrito , Humanos , Neón
11.
Artículo en Inglés | MEDLINE | ID: mdl-12136182

RESUMEN

Using radioimmunoassay and Northern blot, the differences in endothelin and its mRNA expression were studied for cultured cerebral micro-vascular endothelial cells (from WKY and SHR rats) which exposed to flow shear stress at 0, 0.5, 1, 2 Pa for 24 h. The results showed that the endothelin and its mRNA expression of endothelial cells from both WKY and SHR rats proportionally increased according to the shear stress values at 0, 0.5 and 1 Pa, at 2 Pa, however the endothelin and its mRNA expression did not increase further. When comparing both rat systems, the SHR's levels of endothelin and its mRNA expression were higher than WKY's. The results indicated that the levels of endothelin and its mRNA expression were proportional to shear stress in 0-1 Pa in WKY and SHR rat systems and the levels of endothelin and its mRNA of SHR system were higher than those of WKY's. Our results indicate that the vascular wall in SHR system may be more contractile, less relaxative, with lower remodeling ability and thus more easily to mediate atherosclerosis.

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