How to optimize course learning resources and learning methods to promote higher-order learning is an important research topic in current teaching reform. Based on the background of the big data era, ...this paper uses the MOOC network to build an open-sharing platform for physical education teaching course resources. Firstly, the MOOC network classroom teaching model is summarized through the analysis paradigm of the MOOC platform analyzing indicators to deal with teaching big data. The third-order nonlinear model is used in the teaching model to dynamically express the physical education teaching resource-sharing design system and establish a physical education simulation model. In the simulation model, the search optimal solution is improved for resource platform search, and global search is performed when the inertia factor is large and local search is performed when it is small. The univariate validation test for group S students revealed that the mean value of the performance of the answers selected by group S students before the test compared to after the test changed from negative to positive, from -0.46 to 0.16, which was a significant improvement. It can be seen that the teaching model based on the MOOC web-supported open-sharing platform of physical education course resources has positively contributed to students’ learning performance, learning interest, and independent learning ability.
Background
To evaluate the association of preoperative clinical and sonographic features with central lymph node metastasis (CLNM) in patients with clinically node‐negative (cN0) papillary thyroid ...carcinoma (PTC) without capsule invasion.
Methods
Clinical and sonographic features of 635 cN0 PTC nodules without capsule invasion were retrospectively reviewed. CLNM was confirmed by pathology. Univariate and multivariate analyses were performed to analyze the predicting factors associated with CLNM in cN0 PTC without capsule invasion.
Results
In the 635 cN0 PTC nodules without capsule invasion, age ≤36 years, male, tumor size >8 mm, the distance between the tumor and the capsule ≤1.1 mm and calcification were independently associated with CLNM (P < .05).
Conclusions
CLNM was associated with age, sex, tumor size, the distance between the tumor and the capsule, and calcification in cN0 PTC without capsule invasion. Preoperative assessment of risk factors could help to select PTC patients who benefit from surgery.
A questionnaire was used to investigate the knowledge and experience of university students in Jilin Province regarding innovation and entrepreneurship. A non-parametric test was used to analyze ...whether there were significant differences in knowledge perception, and experience of innovation and entrepreneurship between paired samples and independent samples. The results showed significant disparities in students’ knowledge perception, and experience of innovation and entrepreneurship. No significant differences in knowledge perception, or experience of innovation and entrepreneurship were found between the male and female samples. Significant differences in both aspects were found between samples at different stages. All this suggests that as students grow in age and work experience, their knowledge perception, and experience of innovation and entrepreneurship are continuously enriched. To ease the pressure on employment, university students should be actively encouraged to innovate and start businesses.
The cathode materials for sodium‐sulfur batteries have attracted great attention since cathode is one of the important components of the sodium‐sulfur battery, and there are cathode materials that ...have high capacity, non‐toxicity, and cost‐efficiency. Nevertheless, due to their low Coulombic efficiency and proneness to cycling decay, the practical application of the sodium–sulfur battery has always been suppressed. In terms of the responsibility of these problems, the polysulfide shuttle and the sluggish kinetics are the main culprits. To address these issues, impeding the notorious reaction between polysulfide intermediates on the cathode and improve the kinetics reaction on the anode are extremely important. Herein, a comprehensive review is prepared of different approaches to increasing the electrochemical performance and strengthening the stability of cathodes. The influences of various choices and the consequent properties of the cathode in relation to the whole sodium–sulfur battery performance is investigated. Finally, the current research challenges related to cathodes for sodium–sulfur batteries and future perspectives are also discussed.
The shuttle effect and sluggish kinetics are critical challenges for the sulfur cathodes of room temperature sodium‐sulfur (RT Na‐S) batteries. To achieve excellent performance, many strategies have been implemented to address these challenges. In this review, the recent developments on sulfur cathodes is summarized and divide them into five types. Perspectives on sulfur cathodes for RT Na‐S batteries are provided for future improvements.
Layered transition metal oxide (NaxTMO2), being one of the most promising cathode candidates for sodium‐ion batteries (SIBs), have attracted intensive interest because of their nontoxicity, high ...theoretical capacities, and easy manufacturability. However, their physical and electrochemical properties of water sensitivity, sluggish Na+ transport kinetics, and irreversible multiple‐phase translations hinder the practical application. Here, a concept of surface lattice‐matched engineering is proposed based on in situ spinel interfacial reconstruction to design a spinel coating P2/P3 heterostructure cathode material with enhanced air stability, rate, and cycle performance. The novel structure and its formation process are verified by transmission electron microscopy and in situ high‐temperature X‐ray diffraction. The electrode exhibits an excellent rate performance with the highly reversible phase transformation demonstrated by in situ charging/discharging X‐ray diffraction. Additionally, even after a rigorous water sensitivity test, the electrode materials still retain almost the same superior electrochemical performance as the fresh sample. The results show that the surface spinel phase can play a vital role in preventing the ingress of water molecules, improving transport kinetics, and enhancing structural integrity for NaxTMO2 cathodes. The concept of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction will be helpful for designing new ultra‐stable cathode materials for high‐performance SIBs.
The formation process and function mechanism for inhibiting phase transformation and enhancing air stability of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction are studied. This strategy of designing heterostructure with in situ interfacial reconstruction will inspire the exploitation of new chemistries and materials.
Abstract
Autoimmune thyroid disease (AITD) is one of the most frequent autoimmune disorders. However, the pathogenesis of AITD has not been fully elucidated. Recently, accumulating evidence has ...demonstrated that abnormal expression of noncoding RNAs (ncRNAs) is closely related to the etiopathogenesis of AITD. microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) are 3 major groups of ncRNAs that are attracting increasing attention. Herein, we summarized our present knowledge on the role of miRNAs, lncRNAs, and circRNAs in AITD. This review focused on the importance of ncRNAs in development of the most prevalent AITD, such as Hashimoto disease and Graves’ diseases. Altogether, the main purpose of this review is to provide new insights in the pathogenesis of AITD and the possibility of developing novel potential therapeutic targets.
Mortality rates of coronavirus disease‐2019 (COVID‐19) continue to rise across the world. Information regarding the predictors of mortality in patients with COVID‐19 remains scarce. Herein, we ...performed a systematic review of published articles, from 1 January to 24 April 2020, to evaluate the risk factors associated with mortality in COVID‐19. Two investigators independently searched the articles and collected the data, in accordance with PRISMA guidelines. We looked for associations between mortality and patient characteristics, comorbidities, and laboratory abnormalities. A total of 14 studies documenting the outcomes of 4659 patients were included. The presence of comorbidities such as hypertension (odds ratio OR, 2.5; 95% confidence interval CI, 2.1‐3.1; P < .00001), coronary heart disease (OR, 3.8; 95% CI, 2.1‐6.9; P < .00001), and diabetes (OR, 2.0; 95% CI, 1.7‐2.3; P < .00001) were associated with significantly higher risk of death amongst patients with COVID‐19. Those who died, compared with those who survived, differed on multiple biomarkers on admission including elevated levels of cardiac troponin (+44.2 ng/L, 95% CI, 19.0‐69.4; P = .0006); C‐reactive protein (+66.3 µg/mL, 95% CI, 46.7‐85.9; P < .00001); interleukin‐6 (+4.6 ng/mL, 95% CI, 3.6‐5.6; P < .00001); D‐dimer (+4.6 µg/mL, 95% CI, 2.8‐6.4; P < .00001); creatinine (+15.3 µmol/L, 95% CI, 6.2‐24.3; P = .001); and alanine transaminase (+5.7 U/L, 95% CI, 2.6‐8.8; P = .0003); as well as decreased levels of albumin (−3.7 g/L, 95% CI, −5.3 to −2.1; P < .00001). Individuals with underlying cardiometabolic disease and that present with evidence for acute inflammation and end‐organ damage are at higher risk of mortality due to COVID‐19 infection and should be managed with greater intensity.
Highlights
This systematic review and meta‐analysis of 14 studies including a total of 4659 patients comprehensively identifies the risk factors associated with mortality in COVID‐19 included clinical comorbidities such as hypertension, coronary heart disease, and diabetes, as well as laboratory abnormalities including elevated levels of cardiac troponin, interleukin‐6, C‐reactive protein, D‐dimer and markers of liver and renal function.
Layered materials consist of molecular layers stacked together by weak interlayer interactions. They often crystallize to form atomically smooth thin films, nanotubes, and platelet or fullerene-like ...nanoparticles due to the anisotropic bonding. Structures that predominately expose edges of the layers exhibit high surface energy and are often considered unstable. In this communication, we present a synthesis process to grow MoS2 and MoSe2 thin films with vertically aligned layers, thereby maximally exposing the edges on the film surface. Such edge-terminated films are metastable structures of MoS2 and MoSe2, which may find applications in diverse catalytic reactions. We have confirmed their catalytic activity in a hydrogen evolution reaction (HER), in which the exchange current density correlates directly with the density of the exposed edge sites.
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