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1.
J Am Chem Soc ; 145(27): 14903-14911, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37312284

RESUMEN

The interfacial structure of heterogeneous catalysts determines the reaction rate by adjusting the adsorption behavior of reaction intermediates. Unfortunately, the catalytic performance of conventionally static active sites has always been limited by the adsorbate linear scaling relationship. Herein, we develop a triazole-modified Ag crystal (Ag crystal-triazole) with dynamic and reversible interfacial structures to break such a relationship for boosting the catalytic activity of CO2 electroreduction into CO. On the basis of surface science measurements and theoretical calculations, we demonstrated the dynamic transformation between adsorbed triazole and adsorbed triazolyl on the Ag(111) facet induced by metal-ligand conjugation. During CO2 electroreduction, Ag crystal-triazole with the dynamically reversible transformation of ligands exhibited a faradic efficiency for CO of 98% with a partial current density for CO as high as -802.5 mA cm-2. The dynamic metal-ligand coordination not only reduced the activation barriers of CO2 protonation but also switched the rate-determining step from CO2 protonation to the breakage of C-OH in the adsorbed COOH intermediate. This work provided an atomic-level insight into the interfacial engineering of the heterogeneous catalysts toward highly efficient CO2 electroreduction.

2.
Front Psychol ; 14: 1110798, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36993881

RESUMEN

Introduction: College students have become a high prevalence group and vulnerable group of depression. The present study aims to explore the effect of perceived stress on depression in a sample of Chinese college students and proposes that both emotion regulation and positive psychological capital play a moderating role between the two, so as to provide rational intervention for the prevention of potential depression among college students. Method: In this study, 1,267 college students (46.4% female) from a university in western China were selected for the study using a whole-group convenience sampling method. Results: After controlling for gender, this study found that both cognitive reappraisal and positive psychological capital positively moderated the relationship between perceived stress and depression, and both significantly inhibited depression in high and low stress perceivers, and the inhibitory effect was more pronounced in high stress perceivers, but expression inhibition did not moderate the relationship between perceived stress and depression. Discussion: The results suggest that college students can be helped to cope with the negative effects of perceived stress on depression by increasing the frequency of their use of cognitive reappraisal strategies and encouraging the accumulation of positive psychological capital. This study provides theoretical and practical implications for rational interventions for depression among college students.

3.
Molecules ; 27(9)2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35566346

RESUMEN

Psoriasis is reported to be a common chronic immune-mediated skin disease characterized by abnormal keratinocytes and cell proliferation. Perilla leaves are rich in essential oils, fatty acids, and flavonoids, which are recognized for their antioxidant and anti-inflammatory effects. In this study, the alleviating effect of essential oil (PO) extracted from Perilla frutescens stems and leaves on imiquimod (IMQ) -induced psoriasis-like lesions in BALB/c mice were investigated. Results showed that PO ameliorated psoriasis-like lesions in vivo, reduced the expression of lymphocyte antigen 6 complex locus G6D (Ly-6G), which is a marker of neutrophil activation, and inhibited the expression of inflammatory factors interleukin 1 (IL-1), interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX2). In addition, PO significantly decreased the expression of cytokines such as IL-6, IL-1, interleukin 23 (IL-23), interleukin 17 (IL-17), and nuclear factor kappa-B (NF-κB). Furthermore, the down-regulation of mRNA levels of psoriasis-related pro-inflammatory cytokines, such as IL-17, interleukin 22 (IL-22), IL-23, interferon-α (IFN-α), and Interferon-γ (IFN-γ) was observed with the treatment of PO. All results show a concentration dependence of PO, with low concentrations showing the best results. These results suggest that PO effectively alleviated psoriasis-like skin lesions and down-regulated inflammatory responses, which indicates that PO could potentially be used for further studies on inflammation-related skin diseases such as psoriasis and for the treatment of psoriasis such as psoriasis natural plant essential oil resources.


Asunto(s)
Dermatitis , Aceites Volátiles , Perilla frutescens , Psoriasis , Animales , Citocinas/metabolismo , Dermatitis/patología , Modelos Animales de Enfermedad , Imiquimod/efectos adversos , Interleucina-1 , Interleucina-17 , Interleucina-23 , Interleucina-6/farmacología , Queratinocitos , Ratones , Ratones Endogámicos BALB C , Aceites Volátiles/efectos adversos , Perilla frutescens/metabolismo , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Piel/metabolismo
4.
Front Psychol ; 13: 835171, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35265020

RESUMEN

Based on Embodied Cognition Theory, Inhibitory Decline Theory, and Risk Protective Factors Model, this study verified that body mass index (BMI) affects secondary school students' academic performance through the mechanism of inhibitory control. In addition, it was verified that the strength of this mechanism depends on the teacher, parent, and peer support received by secondary school students. By using height and weight measurements, the classic stroop task, and the social support scale, 264 secondary school students in Shanxi Province, China, were surveyed and their academic performance was collected. The results showed that students with high BMI had poorer academic performance, and inhibitory control partially mediated the effect between BMI and academic performance, with the inhibitory control mediated effect accounting for 36.68% of the total effect. Support from teachers, parents, and peers can ameliorate the negative effects of BMI on academic performance, with teacher support and parental support also ameliorating the negative effects of BMI on inhibitory control. Thus, high BMI impairs inhibitory control and thus has a negative impact on academic performance, which can be buffered by social support.

5.
Front Psychol ; 13: 1087668, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36619035

RESUMEN

Purpose: The objective of this study is to investigate the relationship between meaning in life and adolescent self-control, as well as the role of perceived social support and gender in this pathway. Methods: For this purpose, a total of 936 adolescents from two high schools were selected as subjects in this study. The Meaning in Life Scale, the Self-Control Scale, and the Perceived Social Support Scale were used for the research. Results: The results obtained in this study have shown that meaning in life is a significant positive predictor of adolescent self-control and perceived social support. In addition, perceived social support partially mediates the relationship between meaning in life and self-control. Further, it has been found that gender moderates the second half of the pathway of the mediation model of meaning in life on self-control, specifically, perceived social support is a stronger predictor of self-control for females than for males. Conclusion: The results of this study suggest that enhancing perceived social support promotes self-control in adolescents with lower meaning in life, and this process is more pronounced in females.

6.
Front Neurosci ; 15: 689791, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335165

RESUMEN

Recently, emotion classification from electroencephalogram (EEG) data has attracted much attention. As EEG is an unsteady and rapidly changing voltage signal, the features extracted from EEG usually change dramatically, whereas emotion states change gradually. Most existing feature extraction approaches do not consider these differences between EEG and emotion. Microstate analysis could capture important spatio-temporal properties of EEG signals. At the same time, it could reduce the fast-changing EEG signals to a sequence of prototypical topographical maps. While microstate analysis has been widely used to study brain function, few studies have used this method to analyze how brain responds to emotional auditory stimuli. In this study, the authors proposed a novel feature extraction method based on EEG microstates for emotion recognition. Determining the optimal number of microstates automatically is a challenge for applying microstate analysis to emotion. This research proposed dual-threshold-based atomize and agglomerate hierarchical clustering (DTAAHC) to determine the optimal number of microstate classes automatically. By using the proposed method to model the temporal dynamics of auditory emotion process, we extracted microstate characteristics as novel temporospatial features to improve the performance of emotion recognition from EEG signals. We evaluated the proposed method on two datasets. For public music-evoked EEG Dataset for Emotion Analysis using Physiological signals, the microstate analysis identified 10 microstates which together explained around 86% of the data in global field power peaks. The accuracy of emotion recognition achieved 75.8% in valence and 77.1% in arousal using microstate sequence characteristics as features. Compared to previous studies, the proposed method outperformed the current feature sets. For the speech-evoked EEG dataset, the microstate analysis identified nine microstates which together explained around 85% of the data. The accuracy of emotion recognition achieved 74.2% in valence and 72.3% in arousal using microstate sequence characteristics as features. The experimental results indicated that microstate characteristics can effectively improve the performance of emotion recognition from EEG signals.

7.
Nat Prod Res ; 35(24): 5977-5980, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32856487

RESUMEN

Blumea balsamifera essential oils (BBEOs) and Magnolia sieboldii essential oils (MSEOs) have exhibited outstanding antioxidant, anti-bacterial and anti-inflammatory activities. However, their anti-photoaging ability is still unclear. In this study, the chemical compositions of BBEOs and MSEOs are firstly determined by GC-MS analysis, and then their anti-photoaging is evaluated via an ultraviolet radiation (UV-B) induced mice skin-injury model. A total of 35 and 33 components are identified from BBEOs and MSEOs, and their dominant compositions are caryophyllene (18.54%) and borneol (18.33%) in BBEOs, and ß-elemene (29.10%), γ-terpinene (17.01%) and (E)-ß-ocymene (11.69%) in MSEOs. According to the skin injury model, the application of BBEOs and MSEOs to mice skin can effectively inhibit skin photoaging by down-regulating the expression of inflammatory factors including TNF-α, IL-6 and IL-10. Clearly, both essential oils reveal the potential as additives in cosmetics for anti-photoaging.


Asunto(s)
Asteraceae , Magnolia , Aceites Volátiles , Envejecimiento de la Piel , Animales , Ratones , Aceites Volátiles/farmacología , Rayos Ultravioleta
8.
Int J Biometeorol ; 62(2): 141-151, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28864884

RESUMEN

Precipitation is a primary environmental factor in the semiarid grasslands of northern China. With increased concentrations of atmospheric greenhouse gases, precipitation regimes will change, and high-impact weather events may be more common. Currently, many ecophysiological indicators are known to reflect drought conditions, but these indicators vary greatly among species, and few studies focus on the applicability of these drought indicators under high CO2 conditions. In this study, five precipitation levels (- 30%, - 15%, control, + 15%, and + 30%) were used to simulate the effects of precipitation change on 18 ecophysiological characteristics in Stipa bungeana, including leaf area, plant height, leaf nitrogen (N), and chlorophyll content, among others. Two levels of CO2 concentration (ambient, 390 ppm; 550 ppm) were used to simulate the effects of elevated CO2 on these drought indicators. Using gray relational analysis and phenotypic plasticity analysis, we found that total leaf area or leaf number (morphology), leaf water potential or leaf water content (physiology), and aboveground biomass better reflected the water status of S. bungeana under ambient and elevated CO2 than the 13 other analyzed variables. The sensitivity of drought indicators changed under the elevated CO2 condition. By quantifying the relationship between precipitation and the five most sensitive indicators, we found that the thresholds of precipitation decreased under elevated CO2 concentration. These results will be useful for objective monitoring and assessment of the occurrence and development of drought events in S. bungeana grasslands.


Asunto(s)
Dióxido de Carbono/farmacología , Poaceae/efectos de los fármacos , Lluvia , Biomasa , Sequías , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Poaceae/crecimiento & desarrollo
9.
Artículo en Chino | MEDLINE | ID: mdl-26653238

RESUMEN

OBJECTIVE: To determine the tricuspid annular plane systolic excursion (TAPSE) using M-mode echocardiography, and to evaluate the right ventricular systolic function in patients with pneumoconiosis. METHODS: One hundred and eighty-three patients with pneumoconiosis were enrolled as subjects, and one hundred and ninety-nine healthy volunteers were used as controls. According to the types of ventilation dysfunction, patients were divided into four groups: normal type, obstructive type, restrictive type, and mixed type. In the apex four-chamber sections, the displacement of tricuspid annular plane on the right ventricular free wall side was measured from end-diastole to end-systole using M-mode echocardiography. RESULTS: The average TAPSE in the pneumoconiosis group was significantly lower than that in the control group (18.61 ± 3.08 vs 22.38 ± 3.03 mm, P < 0.01). Along with the progression of pneumoconiosis, the TAPSE values in patients with stage I, II, and III pneumoconiosis were significantly decreased compared with those in the control group (P < 0.01). The TAPSE values in patients diagnosed with normal, obstructive, restrictive, and mixed types of pneumoconiosis in pulmonary function tests were all significantly lower than those in the control group (P < 0.01). Among all patients, patients with mixed type of pneumoconiosis had the most significant reduction in the TAPSE. CONCLUSION: The TAPSE is substantially decreased in patients with pneumoconiosis and further decreased along with the progression of pneumoconiosis. Measurement of the TAPSE is an easy way to evaluate the right ventricular systolic function in patients with pneumoconiosis.


Asunto(s)
Neumoconiosis/fisiopatología , Válvula Tricúspide/fisiopatología , Función Ventricular Derecha , Estudios de Casos y Controles , Ecocardiografía , Humanos , Sístole
10.
Ecol Evol ; 5(14): 2956-65, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26306179

RESUMEN

Nitrogen (N) serves as an important mineral element affecting plant productivity and nutritional quality. However, few studies have addressed the interactive effects of elevated CO2 and precipitation change on leaf N of dominant grassland genera such as Stipa L. This has restricted our understanding of the responses of grassland to climate change. We simulated the interactive effects of elevated CO2 concentration and varied precipitation on leaf N concentration (Nmass) of four Stipa species (Stipa baicalensis, Stipa bungeana, Stipa grandis, and Stipa breviflora; the most dominant species in arid and semiarid grassland) using open-top chambers (OTCs). The relationship between the Nmass of these four Stipa species and precipitation well fits a logarithmic function. The sensitivity of these four species to precipitation change was ranked as follows: S. bungeana > S. breviflora > S. baicalensis > S. grandis. The Nmass of S. bungeana was the most sensitive to precipitation change, while S. grandis was the least sensitive among these Stipa species. Elevated CO2 exacerbated the effect of precipitation on Nmass. Nmass decreased under elevated CO2 due to growth dilution and a direct negative effect on N assimilation. Elevated CO2 reduced Nmass only in a certain precipitation range for S. baicalensis (163-343 mm), S. bungeana (164-355 mm), S. grandis (148-286 mm), and S. breviflora (130-316 mm); severe drought or excessive rainfall would be expected to result in a reduced impact of elevated CO2. Elevated CO2 affected the Nmass of S. grandis only in a narrow precipitation range. The effect of elevated CO2 reached a maximum when the amount of precipitation was 253, 260, 217, and 222 mm for S. baicalensis, S. bungeana, S. grandis, and S. breviflora, respectively. The Nmass of S. grandis was the least sensitive to elevated CO2. The Nmass of S. breviflora was more sensitive to elevated CO2 under a drought condition compared with the other Stipa species.

11.
Pharm Biol ; 49(9): 900-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21591990

RESUMEN

CONTEXT: Panax ginseng C. A. Mey (Araliaceae) has been widely used in clinic for treatment of cardiovascular diseases in China. Ginsenoside Rb3 is the main chemical component of Panax ginseng. OBJECTIVE: The aim of this study was to evaluate the effect of ginsenoside Rb3 on myocardial ischemia-reperfusion injury in rats. METHODS: Sprague--Dawley rats were orally treated with Rb3 (5, 10 or 20 mg/kg) daily for 3 days followed by subjecting to left anterior descending coronary artery ligation for 30 min and reperfusion for 24 h. RESULTS: This study showed that ginsenoside Rb3 treatment resulted in a reduction in myocardial infarct size. Ginsenoside Rb3 significantly attenuated the changes of creatine kinase activity and lactate dehydrogenase activity. The cardioprotective effect of ginsenoside Rb3 was further confirmed by histopathological examination. Ginsenoside Rb3 alleviated the increase of malondialdehyde content and the decrease of superoxide dismutase activity in left ventricle. Treatment with ginsenoside Rb3 also decreased plasma endothelin and angiotensin II levels. CONCLUSION: These findings suggested that ginsenoside Rb3 possesses the effect against myocardial IR injury and the underlying mechanism is related to its antioxidant activity and microcirculatory improvement.


Asunto(s)
Cardiotónicos/uso terapéutico , Ginsenósidos/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Angiotensina II/sangre , Animales , Antioxidantes/química , Antioxidantes/farmacología , Cardiotónicos/química , Cardiotónicos/farmacología , China , Creatina Quinasa/sangre , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Endotelinas/sangre , Ginsenósidos/química , Ginsenósidos/farmacología , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , L-Lactato Deshidrogenasa/sangre , Malondialdehído/análisis , Infarto del Miocardio/patología , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/prevención & control , Panax , Extractos Vegetales/química , Extractos Vegetales/farmacología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Método Simple Ciego , Superóxido Dismutasa/análisis , Superóxido Dismutasa/biosíntesis
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