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1Associations between parental support for physical activity and moderate-to-vigorous physical activity among Chinese school children: A cross-sectional study显示文摘Purpose: The objective of this study was to examine the associations between parental support for physical activity(PA) and levels of moderate-to-vigorous physical activity(MVPA) among Chinese school children.Methods: Study participants were 81,857 school-aged children(aged 9–17 years; mean age = 13 years; 49.0% boys) and their parents or guardians who took part in the 2016 Physical Activity and Fitness in China—The Youth Study project. The independent variables included various forms of parental support for PA ascertained through a survey completed by parents or guardians. The dependent variable was the children's average MVPA in minutes per day by self-report. Structure equation modeling was used to examine the associations between parental support for PA and children's MVPA minutes.Results: The overall mean for MVPA participation time for the child participants was 48.82 ± 28.71 min/day. Significant associations between various forms of parental support and MVPA among children were found. Parental encouragement, accompanying, financial support, involvement,and role modeling for PA were positively associated with a high level of student MVPA participation. Parental PA knowledge-sharing was not associated with MVPA. The patterns of the associations were similar across sex, residence locale(i.e., urban and rural), and school grades(primary,junior middle, and junior high schools).Conclusion: Findings from this study suggest that, among Chinese school children, parental support for PA is important in promoting and facilitating children's participation in MVPA.Yang Liu Yajun Zhang Sitong Chen Jialin Zhang Zongchen Guo Peijie Chen 2017Journal of Sport and Health Science2017,6,4:7
2Mathematical and computational approaches to epidemic modeling: a comprehensive review显示文摘Wei DUAN Zongchen FAN Peng ZHANG Gang GUO Xiaogang QIU 2015Frontiers of Computer Science2015,9,5:7
3The receptor—mediated accumulation of triglyceride in macrophage exposed to very low density lipoproteins显示文摘Feng Zongchen Sandra R. Bates Godfrey S. Getz Robert W. Wissler 1983Acta Academiae Medicinae Wuhan1983,,1:1
4Pathogenesis of early cardiac myocyte damage after severe burns显示文摘Huang Yuesheng Yang Zongchen Yan Baigang 1999J Trauma1999,25,:1
5Pathogenesis of early cardiac myocyte damage after severe burns显示文摘Huang Yuesheng Yang Zongchen Li Ao 1999J Traurna1999,46,:1
6How did the Tonga volcanic tsunami on January 15,2022,affect Chinese coasts?显示文摘At 12:15 on January 15,2022(Beijing time),a massive eruption of the Hunga Tonga-Hunga Ha'apai volcano produced violent atmospheric fluctuations,which in turn generated a global tsunami through an abrupt air pressure shock upon the sea surface.Two main components of tsunami waves,phase-locked waves and free gravity waves,were identified by significant differences in propagating speeds across the deep ocean.The phase-locked wave propagated through the ocean basin synchronously with the atmospheric Lamb wave at an average speed of approximately 306 m/s,followed by the free gravity wave at a slower speed.The locked wave reached the coast of eastern Taiwan Island at about 20:00 on January 15,in coincidence with the Lamb wave arrival.However,on the coast of Chinese mainland,tidal gauges did not record tsunami signals until at least 2 h after the Lamb wave arrivals.Theoretical analyses and numerical experiments both suggested that as a result of the incoming wave shoaling above the vast continental shelf of Chinese mainland,the locked wave was no longer trapped by the air pressure shock and gradually transformed into freely-propagating shallow water waves by slowing down its propagation.Due to the longlasting planetary atmospheric fluctuations circling the earth many times,the sea level oscillations continuously propagated onto the Chinese shelf,which resulted in the tsunami waves excited along the Chinese coasts for at least 36 h.The maximum wave amplitude recorded on the coast of eastern Taiwan Island was 44 cm at Wushi,while on the coasts of eastern and southern Chinese mainland,the maximum amplitudes were 22 cm at Shipu and 13 cm at Zhuhai.Fourier and wavelet analyses were performed to identify the major components of the tsunami waves on the Chinese coasts.The results indicated that eastern Taiwan Island was impacted mainly by the waves with periods of approximately 10-40 min.Chinese mainland was hit by the evolved shallow water waves and subsequent free waves,with periods of approximately 40-100 and 16-20 min,respectively.Zongchen WANG Zhiguo XU Ye YUAN Huaiwei YANG Lining SUN Peitao WANG Tingting FAN 2023Science China Earth Sciences2023,66,5:0
7Observations and modelling of the travel time delay and leading negative phase of the 16 September 2015 Illapel,Chile tsunami显示文摘The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics from the tsunami records at 21 Deep-ocean Assessment and Reporting of Tsunami(DART)sites and 29 coastal tide gauge stations.The results revealed systematic travel time delay of as much as 22 min(approximately 1.7%of the total travel time)relative to the simulated long waves from the 2015 Chilean tsunami.The delay discrepancy was found to increase with travel time.It was difficult to identify the LNP from the near-shore observation system due to the strong background noise,but the initial negative phase feature became more obvious as the tsunami propagated away from the source area in the deep ocean.We determined that the LNP for the Chilean tsunami had an average duration of 33 min,which was close to the dominant period of the tsunami source.Most of the amplitude ratios to the first elevation phase were approximately 40%,with the largest equivalent to the first positive phase amplitude.We performed numerical analyses by applying the corrected long wave model,which accounted for the effects of seawater density stratification due to compressibility,self-attraction and loading(SAL)of the earth,and wave dispersion compared with observed tsunami waveforms.We attempted to accurately calculate the arrival time and LNP,and to understand how much of a role the physical mechanism played in the discrepancies for the moderate transoceanic tsunami event.The mainly focus of the study is to quantitatively evaluate the contribution of each secondary physical effect to the systematic discrepancies using the corrected shallow water model.Taking all of these effects into consideration,our results demonstrated good agreement between the observed and simulated waveforms.We can conclude that the corrected shallow water model can reduce the tsunami propagation speed and reproduce the LNP,which is observed for tsunamis that have propagated over long distances frequently.The travel time delay between the observed and corrected simulated waveforms is reduced to<8 min and the amplitude discrepancy between them was also markedly diminished.The incorporated effects amounted to approximately 78%of the travel time delay correction,with seawater density stratification,SAL,and Boussinesq dispersion contributing approximately 39%,21%,and 18%,respectively.The simulated results showed that the elastic loading and Boussinesq dispersion not only affected travel time but also changed the simulated waveforms for this event.In contrast,the seawater stratification only reduced the tsunami speed,whereas the earth’s elasticity loading was responsible for LNP due to the depression of the seafloor surrounding additional tsunami loading at far-field stations.This study revealed that the traditional shallow water model has inherent defects in estimating tsunami arrival,and the leading negative phase of a tsunami is a typical recognizable feature of a moderately strong transoceanic tsunami.These results also support previous theory and can help to explain the observed discrepancies.Peitao Wang Zhiyuan Ren Lining Sun Jingming Hou Zongchen Wang Ye Yuan Fujiang Yu 2021Acta Oceanologica Sinica2021,40,11:0
8Hyperspectral remote sensing identification of marine oil emulsions based on the fusion of spatial and spectral features显示文摘Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine environments.However,the spectrum of oil emulsions changes due to different water content.Hyperspectral remote sensing and deep learning can use spectral and spatial information to identify different types of oil emulsions.Nonetheless,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning models.To address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information method.Using oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil emulsions.The results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and seawater.The number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion identification model has a certain degree of transferability and can effectively identify oil spill emulsions for AVIRIS data at different times and locations,with an overall accuracy of more than 80%,Kappa coefficient of more than 0.7,and F1 score of 0.75 or more for each category.(4)As the spectral resolution decreasing,the model yields different degrees of misclassification for areas with a mixed distribution of oil slick and seawater or mixed distribution of WO and OW.Based on the above experimental results,we demonstrate that the oil emulsion identification model with spatial–spectral feature fusion achieves a high accuracy rate in identifying oil emulsion using airborne hyperspectral data,and can be applied to images under different spatial and temporal conditions.Furthermore,we also elucidate the impact of factors such as spectral resolution and background water bodies on the identification process.These findings provide new reference for future endeavors in automated marine oil spill detection.Xinyue Huang Yi Ma Zongchen Jiang Junfang Yang 2024Acta Oceanologica Sinica2024,43,3:0
9Extraction Conditions of Essential Oil from Eucalyptus Leaves by Distillation显示文摘[Objectives]To explore the extraction conditions of essential oil from eucalyptus leaves.[Methods]The essential oil of eucalyptus leaves was extracted by steam distillation,and the yields of essential oil from eucalyptus leaves under different extraction times,soaking times and different solid-liquid ratios were analyzed through orthogonal test with three factors and three variables.[Results]The effects of various factors on extraction results were:distillation time>solid-liquid ratio>soaking time.When the extraction time and soaking time were 1.5 and 2 h,and the solid-liquid ratio of eucalyptus leaves to distilled water was 1:10,the yield of essential oil was the highest(0.8%).The yield of essential oil increased with the increase of extraction and soaking time,but when reaching the optimal value,the yield decreased with the extension of time.Increasing the solid-liquid ratio can improve the yield of essential oil,but beyond a certain value the yield increased gradually while the cost performance decreased.[Conclusions]The results will provide some reference for the recovery and utilization of eucalyptus leaves.Shengjie WANG Zongchen WEI Shiming QIU 2023Asian Agricultural Research2023,15,10:0
10Detection of oil spill based on CBF-CNN using HY-1C CZI multispectral images显示文摘Accurate detection of an oil spill is of great significance for rapid response to oil spill accidents.Multispectral images have the advantages of high spatial resolution,short revisit period,and wide imaging width,which is suitable for large-scale oil spill monitoring.However,in wide remote sensing images,the number of oil spill samples is generally far less than that of seawater samples.Moreover,the sea surface state tends to be heterogeneous over a large area,which makes the identification of oil spills more difficult because of various sea conditions and sunglint.To address this problem,we used the F-Score as a measure of the distance between forecast value and true value,proposed the Class-Balanced F loss function(CBF loss function)that comprehensively considers the precision and recall,and rebalances the loss according to the actual sample numbers of various classes.Using the CBF loss function,we constructed convolution neural networks(CBF-CNN)for oil spill detection.Based on the image acquired by the Coastal Zone Imager(CZI)of the Haiyang-1C(HY-1C)satellite in the Andaman Sea(study area 1),we carried out parameter adjustment experiments.In contrast to experiments of different loss functions,the F1-Score of the detection result of oil emulsions is 0.87,which is 0.03–0.07 higher than cross-entropy,hinge,and focal loss functions,and the F1-Score of the detection result of oil slicks is 0.94,which is 0.01–0.09 higher than those three loss functions.In comparison with the experiment of different methods,the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.05–0.12 higher than that of the deep neural networks,supports vector machine and random forests models,and the F1-Score of the detection result of oil slicks is 0.15–0.22 higher than that of the three methods.To verify the applicability of the CBF-CNN model in different observation scenes,we used the image obtained by HY-1C CZI in the Karimata Strait to carry out experiments,which include two studies areas(study area 2 and study area 3).The experimental results show that the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.88,which is 0.16–0.24 higher than that of other methods,and the F1-Score of the detection result of oil slicks is 0.96–0.97,which is 0.06–0.23 higher than that of other methods.Based on all the above experiments,we come to the conclusions that the CBF loss function can restrain the influence of oil spill and seawater sample imbalance on oil spill detection of CNN model thus improving the detection accuracy of oil spills,and our CBF-CNN model is suitable for the detection of oil spills in an area with weak sunglint and can be applied to different scenarios of CZI images.Kai Du Yi Ma Zongchen Jiang Xiaoqing Lu Junfang Yang 2022Acta Oceanologica Sinica2022,41,7:0
11Clavukoelloids A—M,Thirteen Rare N-Containing Nardosinane Type Sesquiterpenoids from the Soft Coral Clavularia koellikeri显示文摘Thirteen new nitrogen-containing nardosinane-type sesquiterpenoids,clavukoelloids A-M(1-13)with unique acrylamide fragments vs.the reported general nardosinane-type sesquiterpenoids containing lactone,were isolated from the soft coral Clavularia koellikeri collected from the South China Sea.The structures and absolute configurations of new compounds were unambiguously determined by analysis of spectroscopic data,CP3,DP4+,ECD spectra,and X-ray diffraction.Compound 6 showed anti-inflammatory activities and hepatoprotective activities in transgenic fluorescent zebrafish.Xiao Han Zhe Wang Anran Fu Kun Liu Zongchen Ma Xuli Tang Dahai Zhang Guoqiang Li 2023Chinese Journal of Chemistry2023,41,12:0
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