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Football has always been a traditional item in sports colleges and universities in China, and is loved by teachers and students, but the traditional teaching mode of football general course has failed to meet the requirements of contemporary high-quality teaching. The author introduces the "match lead-in training" mode into the general football course to carry out teaching experimental research. Through the comparative analysis of the statistics of technical data and the test of special skills in four-person and six-person matches, the author finds that this teaching mode is more conducive to the improvement of students' football technology, skill level and competition ability than that of the traditional football general course. [ABSTRACT FROM AUTHOR]

Power generation estimation is one of the key steps in wind farm micro-sitting, and its accuracy is related to the wake decay constant in the wake model. Considering the influence of wind resource distribution in different regions, this study carried out interval optimization for the wake decay constant of offshore wind farms in the Yellow Sea region of China. Given the very small length of the sea surface roughness, atmospheric stability is a critical factor influencing the wake extent and recovery speed of offshore wind farms. WAsP 10 (Wind Atlas Analysis and Application software) simulates the wake of various scenarios, and the selection range of wake attenuation constant is investigated by combining the cases of two offshore wind farms in the Yellow Sea region. The study found that the higher the atmospheric stability, the larger the wake and the lower the wake attenuation coefficient. The Yellow Sea wind farm's wake error system is between 0.03 and 0.04, and the forecast error can be controlled to within 3%. When simulating the wind farm at Yellow Sea offshore for improving power generation and economic evaluation, it is critical to select the correct value range of wake decay constant. [ABSTRACT FROM AUTHOR]

This paper discusses how the incorporation of high-resolution ground coverage dataset ESA WorldCover into a wind flow field and wake simulation calculation, as well as the use of the coupled wake model for wind farm output simulation, can improve the accuracy of wind resource assessment using engineering examples. In the actual case of grid-connected wind farms in central China, SCADA wind speed data is reconstructed to the free flow wind speed in front of the wind turbine impeller using the transfer function of the nacelle, and the wind farm is modeled using OpenWind software, simulating the wind speed at the height of each wind turbine hub and each wind turbine output. The results show that when other initial data are consistent, using ESA's high-precision land cover dataset WorldCover 10 m to make roughness lengths which improves the wind farm output simulation accuracy by 8.91%, showing that it is worth trying to apply WorldCover 10 m to the wind farm simulation design. At the same time, this case is used to compare and analyze the application of the Eddy-Viscosity wake model and the two coupled wake models based on the Eddy-Viscosity wake model. The results show that the coupled wake model will have higher accuracy than the Deep Array Eddy Viscosity wake model and it is 1.24% more accurate than the Eddy Viscosity wake model, and the ASM Eddy Viscosity wake model is 5.21% more accurate than the Eddy Viscosity wake model. [ABSTRACT FROM AUTHOR]

Highlights • A land-sea coordination system is constructed. • An initial indicator system is established based on analysis of influential factors using questionnaires. • Structural equation modeling is applied to screen the initial indicators. • Reliability and validity analysis of the screened indicator system is conducted to verify its feasibility. • The screened indicator system is suitable for evaluating standard ports. Abstract The evaluation of the development of a land-sea coordination system, including how to measure success, remains a significant subject for exploration among researchers and practitioners. The main challenge in this subject is to establish a suitable indicator system. In this paper, we propose a novel approach to construct an indicator system to evaluate the development of a land-sea coordination system. We take Lianyungang port as a case study. A land-sea coordination system is considered as composed by three sub-systems, i.e., a land-side sub-system, a sea-side sub-system, and a port sub-system. Based on analysis of influential factors using questionnaires for the development of a land-sea coordination system, an initial indicator system is established. We apply structural equation modeling to screen the indicators from the initial indicator system. Finally, we analyze the reliability and validity of the screened indicator system. The results show that a total of 26 indicators are generated and grouped into three major categories: (1) economic development; (2) service system; (3) resources and environment, and the screened indicator system is of suitable feasibility to be applied to evaluate the development of the considered land-sea coordination system. Additionally, the results provide a scientific reference and decision-making basis for policy formulation and development evaluation of standard ports. [ABSTRACT FROM AUTHOR]

The NaBaPO 4 :Eu 2+ ,Yb 3+ quantum-cutting (QC) phosphors were prepared by the solid-state reaction. We confirm the luminescence of Yb 3+ is mainly derived from QC rather than common down-conversion. The QC efficiency η QE calculated from the luminescence decay curves reached a maximum as high as 197.4%. Furthermore, the QC emission was enhanced by decorating with quasi-spherical and uniform (∼100 nm) Ag nano-particles, due to localized surface plasmon resonance. The enhancement factor reached a maximum as 1.2337. [ABSTRACT FROM AUTHOR]

The understanding of the local spatiotemporal characteristics of the relationships among ecosystem services provides an ecological basis for regional sustainable ecosystem management. However, the geographical factors that influence the different changing relationships among the ecosystem services remain unclear, especially for continent-scale future scenarios. In this study, five ecosystem services (ESs) (habitat quality (HQ), soil retention (SR), water yield (WY), crop production (CP) and carbon sequestration (CS)) were measured in the "Belt and Road" region from 2010 to 2030. We qualified the trade-off and synergy among the ESs using Pearson correlations in different ecoregions, at different altitudes and for different population levels. Our results showed that CP exhibited a trade-off with HQ and SR, whereas the relationships among the other ESs were synergistic. Under the RCP4.5 scenario, the synergies between CP and CS and between CP and WY were the strongest, while the trade-offs between CP and SR and between CP and HQ were the strongest under RCP8.5. The relationship of the ecosystem services corresponded well with the regional climate, altitude and population, and the responses of the relationships among ESs to population sizes were the most obvious. This study contributes to investigating the influence of the driving factors on the relationships among ESs under multiple scenarios at the continental scale and could provide credible associations for future land use management and economic development in various countries, as well as promoting construction of a "green Belt and Road". Image 1 • Five ecosystem services were predicted in 2030 under land use scenarios. • Three geographical factors that influence ecosystem service relationships were identified. • Crop production was positively correlated with carbon sequestration and water yield. • Population sizes influence the relationships among ecosystem services. [ABSTRACT FROM AUTHOR]

Cerebral ischemia is associated with a high burden of neurological disability. Recently, emerging evidence has demonstrated that long non-coding RNAs (lncRNAs) are crucial regulators in cerebral ischemia reperfusion (I/R) injury. Herein, we investigated the function and potential mechanism of long intergenic non-protein coding RNA 473 (LINC00473) in cerebral I/R injury. We established oxygen glucose deprivation/reperfusion (OGD/R) model in Neuro-2a (N2a) cells to mimic the cerebral I/R injury in vitro. RT-qPCR and Western blot assays were conducted to detect target gene expression. Functional assays measured the effects of LINC00473 on cell viability, apoptosis and reactive oxygen species (ROS) production. A series of mechanism assays were carried out to detect the potential mechanism of LINC00473 in cerebral I/R injury. LINC00473 was significantly down-regulated in OGD/R-induced injury model. LINC00473 overexpression reversed the reduced cell viability as well as the enhanced apoptosis and ROS level induced by OGD/R. Moreover, LINC00473 functioneds as a competing endogenous RNA (ceRNA) to sponge miR-15b-5p and miR-15a-5p and thereby regulated SRSF protein kinase 1 (SRPK1) expression. Our findings confirmed the protective role of LINC00473 in cerebral I/R injury, which might provide a novel target for treating ischemic brain injury. [ABSTRACT FROM AUTHOR]

Highlights: [•] Host is KYF4, which shows low phonon energy and excellent chemical stability. [•] Quantum-cutting of Tb3 +–Yb3+ occurs under different Tb3+ excitations. [•] Quantum-cutting is effective by exciting 5D3 level of Tb3+. [Copyright &y& Elsevier]

Oceanic glaciers are one of the most sensitive indicators of climate change. However, remotely sensed evidence of land cover change in the oceanic glacial region is still limited due to the cloudy weather during the growing season. In addition, the performance of common machine learning classification algorithms is also worth testing in this cloudy, frigid and mountainous region. In this study, three algorithms, namely, the random forest, back-propagation neural network (BPNN) and convolutional neural network algorithms, were compared in their interpretation of the land cover change in south-eastern Tibet and resulted in three findings. (1) The BPNN achieves the highest overall accuracy and Kappa coefficient compared with the other two algorithms. The overall accuracy was 97.82%, 98.07%, 98.92%, and 94.63% in 1990, 2000, 2007, and 2016, and the Kappa coefficient was 0.958, 0.959, 0.980, and 0.918 in these four years, respectively. (2) From 1990 to 2000, the dominant land cover was ice at the landscape level. The landscape fragmentation decreased and the landscape aggregation increased. From 2000 to 2016, the dominant land cover transformed from ice to vegetation. The vegetation aggregation increased, while the ice aggregation decreased. (3) When the elevation was less than 4 km, the vegetation was usually transformed into bare land; otherwise, the probability of direct transformation between vegetation and ice increased. The findings on the land cover transformation in the oceanic glacial region by multiple classification algorithms can provide both long-term evidence and methodological indications to understand the recent environmental change in the "third pole". [ABSTRACT FROM AUTHOR]