507 research outputs found
Exploring learner factors in second language (L2) incidental vocabulary acquisition through reading
This study examined the predictive role of several learner factors in second language (L2) incidental vocabulary acquisition through reading, including: L2 proficiency, motivation, anxiety, and mastery of strategies. Participants were 129 English learners in a comprehensive university in China. Participants read two English texts and were given an unannounced vocabulary test to assess their incidental vocabulary acquisition. Their levels of motivation, anxiety, and mastery of strategies were measured by three specifically designed instruments that targeted incidental vocabulary acquisition. A multiple linear regression analysis revealed that L2 proficiency, anxiety, and mastery of strategies were positive and significant predictors of incidental vocabulary acquisition, although motivation was not. This confirms the role that learners’ linguistic, affective, and cognitive features play in L2 incidental vocabulary acquisition
Intermittent Prediction Method Based On Marcov Method And Grey Prediction Method
This paper concentrates on the intermittent demand for electric power supply and studies the method of demand prediction. This chapter first divides the demand for electric power supply into two statistical sequences: (1) sequence of demand occurrence, among which “1”stands for the occurrence of demand,“0”means that the demand fails to occur; (2) sequence of demand quantity. Next the author predicts the moment of time and the number of times n that demand occurs within a specific time interval in the future based on 0-1 sequence using Markov arrival process (MAP). Then the paper forecasts the demand quantity in subsequent n intervals using Grey prediction model GM (1, 1) based on the sequence of demand quantity. Finally, the author places the demand quantity in the n intervals in order at the moments where demand occurs to get the predicted result of demand for electric material with intermittent demand. According to instance analysis, the integrated approach mentioned in this paper surpasses existing methods in providing accurate prediction on data of product with intermittent demand
Antiperovskite Li3OCl Superionic Conductor Films for Solid-State Li-Ion Batteries.
Antiperovskite Li3OCl superionic conductor films are prepared via pulsed laser deposition using a composite target. A significantly enhanced ionic conductivity of 2.0 × 10-4 S cm-1 at room temperature is achieved, and this value is more than two orders of magnitude higher than that of its bulk counterpart. The applicability of Li3OCl as a solid electrolyte for Li-ion batteries is demonstrated
The Protective Effect of Yi Shen Juan Bi Pill in Arthritic Rats with Castration-Induced Kidney Deficiency
Androgens have been linked to the onset, severity, and progression of rheumatoid arthritis (RA). In traditional Chinese medicine (TCM), the most common pattern in RA is kidney deficiency, which partly corresponds to a low sex hormone state. In this study, TCM kidney deficiency was induced in male Sprague-Dawley rats with castration surgery, and a TCM preparation, Yi Shen Juan Bi Pill (YJB), was used to treat collagen induced arthritis (CIA) rats with castration. Metabolomic technique was used to evaluate the pharmacological mechanism in castrated CIA rats treated by YJB. The results showed that castration significantly increased the severity of the arthritis in rats but was ameliorated by YJB. Its pharmacological mechanism was partially associated with lipid metabolites involving free fatty acid (FFA) and lysophosphatidylcholine (LPC). In conclusion, the experimental results demonstrate the protective effect of YJB on the TCM kidney deficiency pattern induced by androgen deficiency in CIA rats and support that YJB should be used for the clinical treatment of RA with TCM kidney deficiency pattern
Effects of acute exercise fatigue on the spatiotemporal dynamics of resting-state large-scale brain networks
IntroductionVarious approaches have been used to explore different aspects of the regulation of brain activity by acute exercise, but few studies have been conducted on the effects of acute exercise fatigue on large-scale brain functional networks. Therefore, the present study aimed to explore the effects of acute exercise fatigue on resting-state electroencephalogram (EEG) microstates and large-scale brain network rhythm energy.MethodsThe Bruce protocol was used as the experimental exercise model with a self-controlled experimental design. Thirty males performed incremental load exercise tests on treadmill until exhaustion. EEG signal acquisition was completed before and after exercise. EEG microstates and resting-state cortical rhythm techniques were used to analyze the EEG signal.ResultsThe microstate results showed that the duration, occurrence, and contribution of Microstate C were significantly higher after exhaustive exercise (p’s < 0.01). There was a significantly lower contribution of Microstate D (p < 0.05), a significant increase in transition probabilities between Microstate A and C (p < 0.05), and a significant decrease in transition probabilities between Microstate B and D (p < 0.05). The results of EEG rhythm energy on the large-scale brain network showed that the energy in the high-frequency β band was significantly higher in the visual network (p < 0.05).DiscussionOur results suggest that frequently Microstate C associated with the convexity network are important for the organism to respond to internal and external information stimuli and thus regulate motor behavior in time to protect organism integrity. The decreases in Microstate D parameters, associated with the attentional network, are an important neural mechanism explaining the decrease in attention-related cognitive or behavioral performance due to acute exercise fatigue. The high energy in the high-frequency β band on the visual network can be explained in the sense of the neural efficiency hypothesis, which indicates a decrease in neural efficiency
NiO hollow microspheres interconnected by carbon nanotubes as an anode for lithium ion batteries
In this work, NiO hollow microspheres interconnected by multi-walled carbon nanotubes (MWCNTs) were prepared, characterized, and evaluated in terms of lithium ion storage properties. Characterization results showed that the NiO hollow microspheres were formed by self assembly of NiO nanoparticles promoted by MWCNTs, which connected the NiO microspheres to form a long-range network. Electrochemical measurement results showed a charge capacity as high as 597.2 mAh g when cycling at the rate 2 C and maintained 85.3% capacity of 0.1 C. After cycling for 100 times at 1 C, it maintained a capacity of 692.3 mAh g with retention 89.3% of the initial capacity. The observed excellent electrochemical performance is attributed to the presence of MWCNTs interconnecting the NiO microspheres of the composite material, of which electronic conductivity was improved, and the mesoporous hollow structure effectively alleviated the volume changes to maintain the structural stability during cycling
Le regole del gioco: Primo incontro con l'ingegneria strategica
Cu particles decorated carbon composite
microspheres (CCMs) with
a unique sesame ball structure have been prepared by combining the
mass-producible spray drying technique with calcinations. The conventional
cuprammonium cellulose complex solution obtained by dissolving cellulose
in a cuprammonia solution has been applied as raw materials for the
preparation of Cu(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup>/cellulose
complex microspheres via a spray drying process. The resulted Cu(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup>/cellulose complex microspheres
are then transformed into the Cu particles homogeneously decorated
porous carbon spheres <i>in situ</i> by calcinations at
450 or 550 °C. The coordination effect between the Cu(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup> species and the hydroxyl groups
of the cellulose macromolecules has been exploited for directing the
dispersion of the Cu particles in the resultant composite CCMs. The
antimicrobial effects of the CCMs are evaluated by determining the
minimum growth inhibitory concentrations using Staphylococcus
aureus and Escherichia coli as representatives, respectively. The CCMs show high efficiency
catalytic properties to the conversion of 4-nitrophenol to 4-aminophenol
using NaBH<sub>4</sub> as a reductant in a mild condition. The recyclability
and stability of the CCM catalysts have also been studied
The Th17/Treg Immune Imbalance in Ulcerative Colitis Disease in a Chinese Han Population
Objective. To investigate the Th17/Treg immune balance in the ulcerative colitis (UC) patients in a Chinese Han population. Methods. Ninety UC patients and 30 healthy subjects were enrolled. The serum IL-17 and TGF-β1 levels of these participants were measured with ELISA; the percentage of Th17 and Treg cells in peripheral blood was determined with flow cytometry. Results. In UC patients, the levels of IL-17 and Th17 were significantly higher compared with healthy subjects; the percentage of Th17 and IL-17 level in moderate and severe subgroup was significantly higher than in mild subgroup; a positive correlation existed between these two indexes and clinical activity index and endoscopic evaluation. TGF-β1 level and Treg cells in UC patients were lower than healthy subjects. TGF-β1 level in moderate and severe subgroup was lower than in mild subgroup. There was a negative linear correlation between Treg cells and clinical activity index, endoscopic evaluation. A positive correlation was detected between Treg cells and TGF-β1 level. Conclusions. Th17/Treg immune imbalance might play a crucial role in the development of UC. To induce the production of Treg cells and TGF-β1, inhibit the level of Th17 and IL-17, and thus recover the Th17/Treg immune balance might imply new therapeutic targets in UC management
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