Relationships among Sedentary Time,Electronic Product Addiction,and Depression in Adolescents during the COVID-19 Epidemic:A Cross-Lagged Study

Objective:This study was conducted to explore the relationships among sedentary behavior(SB),electronic product addiction(EPA),and depression(D)in adolescents during the COVID-19 epidemic.Methods:A total of 604 adolescents(including 309 girls and 295 boys aged 12-18)were selected from Qufu City,Shandong Province,China for three rounds of investigation.The model was constructed using AMOS 23.0 software,and cross-lagged analysis was conducted.Results:SB at T1 can significantly positively predict SB and EPA at T2(p<0.05).EPA at T1 can significantly positively predict SB and D at T2(p<0.05).Physical activity level and SB at T2 can significantly predict SB and EPA at T3(p<0.05).EPA at T2 can significantly predict SB,EPA,and D at T3(p<0.05).Conclusions:SB and EPA are predictive factors for D.Moreover,SB can significantly positively predict D and indirectly predict D through the mediating effect of EPA.

Long-Term Extreme Wave Characteristics in the Water Adjacent to China Based on ERA5 Reanalysis Data

Extreme waves have a profound impact on coastal infrastructure;thus,understanding the variation law of risky analysis and disaster prevention in coastal zones is necessary.This paper analyzed the spatiotemporal characteristics of extreme wave heights adjacent to China from 1979 to 2018 based on the ERA5 datasets.Nonstationary extreme value analysis is undertaken in eight repre-sentative points to investigate the trends in the values of 50-and 100-year wave heights.Results show that the mean value of extreme waves is the largest in the eastern part of Taiwan Island and the smallest in the Bohai Sea from 1979 to 2018.Only the extreme wave height in the northeastern part of Taiwan Island shows a significant increase trend in the study area.Nonstationary analysis shows remarkable variations in the values of 50-and 100-year significant wave heights in eight points.Considering the annual mean change,E1,E2,S1,and S2 present an increasing trend,while S3 shows a decreasing trend.Most points for the seasonal mean change demon-strate an increasing trend in spring and winter,while other points show a decreasing trend in summer and autumn.Notably,the E1 point growth rate is large in autumn,which is related to the change in typhoon intensity and the northward movement of the typhoon path.

A Study on the Effectiveness of Autonomous-Cooperative Teaching and Learning Model Based on large -class English Teaching in Higher Vocational College

This paper just focuses on introducing the new model and testing its effectiveness in teaching English. Within this new model, both in-class learning and out-of-class learning are emphasized. In this paper, an experimental study is conducted upon non-English majors to test the effectiveness of autonomous-cooperative teaching and learning model for college English teaching (CET). The experimental study has lasted for half a year. Finally, from the experiment it can prove that the autonomous-cooperative teaching and learning model is feasible for English teaching and learning in large English classes in Higher Vocational College. It can improve English Teaching of Higher Vocational College and the students in the EG would surpass those in the CG in the performance of English learning.

Discussion on the Reform of Mixed-English Teaching Mode of Higher Vocational English Based on “Internet +”

In today’s society,English has become a core competency that everyone needs.How to use the development advantages of“Internet+”and to develop a hybrid teaching method is the main research content of this paper.Based on this,this paper firstly summarizes the problems existing in the mixed teaching mode of vocational English from the aspects of single multimedia teaching form and the utilization rate of modern information teaching tools.Subsequently,combining traditional classroom teaching with flipped classes based on microlecture,developing mixed-English teaching,establishing a self-learning environment for students under the network platform,and proposing suggestions are the guidance for students to use the online platform for independent learning,in order to be able to provides new ideas for higher vocational English mixed teaching reform.

Application Drama in English Teaching:A New Attempt in Theory

In the current English curriculum,there are quite a few practical examples of such lively teachings as games and scene. English teachers are also employing vital and interesting pedagogies to stimulate students' imagination and to improve their ability to communicate in English. However,there are scarce examples to report successful incorporation of drama into teaching. Hence,the goal of this paper is to integrate communicative pedagogy,multiple intelligence,and whole language teaching to drama teaching,so as to obtain the best complementary effects of both in theory.

BIFURCATION ANALYSIS IN A PREDATOR-PREY MODEL WITH AN ALLEE EFFECT AND A DELAYED MECHANISM

Regarding delay-induced predator-prey models, much research has been done on delayed destabilization, but whether delays are stabilizing or destabilizing is a subtle issue. In this study, we investigate predator-prey dynamics affected by both delays and the Allee effect. We analyze the consequences of delays in different feedback mechanisms. The existence of a Hopf bifurcation is studied, and we calculate the value of the delay that leads to the Hopf bifurcation. Furthermore, applying the normal form theory and a center manifold theorem, we consider the direction and stability of the Hopf bifurcation. Finally, we present numerical experiments that validate our theoretical analysis. Interestingly, depending on the chosen delay mechanism, we find that delays are not necessarily destabilizing. The Allee effect generally increases the stability of the equilibrium, and when the Allee effect involves a delay term, the stabilization effect is more pronounced.

Android Malware Detection Using ResNet-50 Stacking

There has been an increase in attacks on mobile devices,such as smartphones and tablets,due to their growing popularity.Mobile malware is one of the most dangerous threats,causing both security breaches and financial losses.Mobile malware is likely to continue to evolve and proliferate to carry out a variety of cybercrimes on mobile devices.Mobile malware specifically targets Android operating system as it has grown in popularity.The rapid proliferation of Android malware apps poses a significant security risk to users,making static and manual analysis of malicious files difficult.Therefore,efficient identification and classification of Androidmalicious files is crucial.Several ConvolutionalNeuralNetwork(CNN)basedmethods have been proposed in this regard;however,there is still room for performance improvement.In this work,we propose a transfer learning and stacking approach to efficiently detect the Android malware files by utilizing two wellknown machine learning models,ResNet-50 and Support Vector Machine(SVM).The proposed model is trained on the DREBIN dataset by transforming malicious APK files into grayscale images.Our model yields higher performance measures than state-of-the-art works on the DREBIN dataset,where the reported measures are accuracy,recall,precision,and F1 measures of 97.8%,95.8%,95.7%,and 95.7%,respectively.

Regulation of A 9-cis-epoxycarotenoid Dioxygenase(NCED)Gene from Raspberry on High Salinity and Cold Tolerance

Abscisic acid(ABA)is a plant hormone that plays an important role in plant development and abiotic stress.The 9-cis-epoxycarotenoid dioxygenase(NCED)is a key rate-limiting enzyme in the ABA biosynthetic pathway.The physiological and molecular mechanisms of NCED regulating plant development and abiotic stress tolerance have been reported in many plant species,but gene function of RiNCEDs in Rubus idaeus L.is rarely reported.In this study,the open reading frame(ORF)sequence of RiNCED2 in red raspberry fruit was isolated and the function of this gene under abiotic stress was investigated.While RiNCED2 was induced by cold,high salinity,drought and ABA,it was highly expressed in new leaves as measured by real-time qPCR.Overexpression of RiNCED2 in Arabidopsis under both high-salt and cold stress increased ABA content,demonstrating that RiNCED2 was involved in ABA biosynthesis.Meanwhile,the leaf wilting degree of transgenic Arabidopsis was less,while the content of malondialdehyde(MDA)was significantly reduced,and the chlorophyll content,proline content,peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)activities were significantly increased.These results indicated that overexpression of RiNCED2 enhanced the resistance of transgenic Arabidopsis to high salt and cold.

Intelligent Oxygen-Enriched and “Sterilized” Underground Gyms: Background, Dilemmas and Pathways

The in-depth integration of healthy China with national fitness and the hope to achieve the long-term goal of “leading Sports Nation” by 2035, can’t be realized without gyms where people do physical exercise. The international academic community recognizes that the 21st century is the golden time for sustainable and quality development. Taking a national perspective, authors of this paper studied the feasibility of building underground gyms in China through the approach of interdisciplinary research, as well as its dilemmas and pathways, and found out that quality development of underground space can effectively address challenges for large cities in China by increasing the resilience of urban area, and give full engage to underground capacity in striving for the goal of carbon peak and carbon neutrality. Underground gyms can also be incorporated into resident’s 15-min fitness circle, satisfying people’s needs of doing exercise at any time and in an easily-accessible place. However, China’s underground area development has been hindered by unclear property rights, chaotic action and utilization, and relatively backward laws and regulations. Moreover, building underground gyms still has to solve many problems such as poor air quality, severe sweat smell, and excessive bacteria and viruses. It is suggested that the capable authorities shall first clarify laws and regulations over place compound utilization, property rights and fire protection to facilitate the process of building underground gyms;encourage fitness practitioners to explore underground areas as gyms, and transfer their ground business to underground;then produce an intelligent and systematic solution of air quality improvement featuring oxygen-enrichment and “sterilization” with integration, a variety of instruments to monitor air quality of indoor gyms in real-time, to realize automatic control and management, and truly create worry-free and oxygen-enriched underground gyms with no sweat smell and no fear of bacteria and viruses.

Hepatic inflammatory myofibroblastic tumor: A case report

BACKGROUND Hepatic inflammatory myofibroblastic tumor(HIMT)is a rare type of hepatic tumor.It is always misdiagnosed and mistreated because it is primarily found with no obvious specific manifestation,and its imaging findings are diverse.CASE SUMMARY Here,we report a case of HIMT that was initially diagnosed as liver malignancy but was confirmed as HIMT by histopathology after hepatectomy.Mostly,HIMTs are infiltrated with plasma cells and stain positively for anaplastic lymphoma kinase on immunohistochemistry as well as for some other kinases.CONCLUSION HIMT can be treated with single nonsteroidal anti-inflammatory drugs and without surgery when it is diagnosed accurately.Because the etiology of HIMT is unknown and the diagnosis is difficult,the pathogenesis and clinical process need to be further studied.

Surface property variations in flotation performance of calcite particles under different grinding patterns

基于料层粉碎工作方式,高压辊磨制备的矿物颗粒具有区别于其他磨矿方式制备颗粒的表面特性,对矿物浮选会产生较大的影响。本文研究了高压辊磨、颚式破碎、干式球磨、湿式球磨及湿式棒磨下方解石纯矿物颗粒的浮选行为,并通过比表面积、粒径分布、原子力学显微镜、表面电子能谱及动电位等手段表征了不同磨矿方式制备颗粒的表面特性以揭示其浮选机理。结果表明:当磨矿细度较低时,相比于其他磨矿方式高压辊磨制备的方解石颗粒在油酸钠和十二胺体系均能够获得更好的浮选指标;由磨矿方式导致的矿物颗粒比表面积、粒度分布、表面粗糙度、Fe^(3+)沾染物、键合能及Zeta电位差异是其浮选行为差异化的主要原因。

高压辊磨终粉磨工艺制备颗粒的均匀性分析（英文）

针对高压辊磨终粉磨工艺中存在的过磨和粒度不均匀现象,本文采用高压辊磨终粉磨、阳离子反浮选以及准静态料层粉碎模拟等试验方法从评价指标、工艺条件参数的影响、颗粒均匀性对浮选的影响及颗粒均匀性强化机制等方面展开研究。理论分析表明,对颗粒均匀性分析的评价指标必须涵盖均匀性系数和平均粒径两个方面;试验结果表明,高压辊磨终粉磨工艺中选粉机循环风机转速对颗粒均匀性影响最为明显,其次是高压辊磨机工作压力和辊缝,辊面转速的影响最弱;颗粒平均粒径对方解石浮选精矿品位有较大影响而均匀性系数对精矿回收率有较大影响,综合考虑浮选精矿回收率和品位,终粉磨制备颗粒的平均粒径最佳值为50~55μm、均匀性系数为1.1~1.2;为了提高产品颗粒均匀性,高压辊磨终粉磨工艺中有利于料层屏蔽效应和密实效应的操作参数应该得到强化。

The Travelling Wave Solutions for （2＋1）-dimensional AKNS Equation

Based on the travelling wave method, a(2 + 1)-dimensional AKNS equation is considered. Elliptic solution and soliton solution are presented and it is shown that the soliton solution can be reduced from the elliptic solution. It also proves that the result is consistent with the soliton solution of simplify Hirota bilinear method by Wazwaz and illustrate the solution are right travelling wave solution.

教育精准扶贫:教育贫困循环累积因果效应破解路径

2020年全面建成小康社会是党的十八大报告中的重要内容,也是中国特色社会主义建设重要目标之一。教育贫困是居民贫困的核心原因,如何破解循环累积因果效应导致的教育贫困已成为当前国家和社会亟须解决的关键问题。全面小康社会建成的核心工作在于精准扶贫,其中,教育精准扶贫又是精准扶贫的重中之重。从循环累积因果效应的内涵出发,通过分析教育贫困循环累积因果效应的形成机制,有望探索出教育贫困循环累积因果效应的可能破解对策。

A preliminary study of neck-stomach syndrome

AIM: To determine the expression of c-Fos, caspase-3 and interleukin-1β (IL-1β) in the cervical cord and stomach of rats with cervical spondylosis, to analyze their relationship, and to offer an explanation of one possible cause for functional dyspepsia (FD) and irritable bowel syndrome (IBS) caused by cervical spondylosis. METHODS: The cervical spondylosis model in rats was established by destroying the stability of cervical posterior column. The cord segments C4-6 and gastric antrum were collected 3 mo and 5 mo after the operation. Rats with the sham operation were used as controls. The expressions of c-Fos, caspase-3 and IL-1β in the cervical cord and gastric antrum were determined by immunohistochemistry and/or Western blot. RESULTS: Immunohistochemical staining showed a few c-Fos, caspase-3 and IL-1β-positive cells in the cervical cord and antrum in the control. There was a significant increase in c-Fos, caspase-3 and IL-1β expression in model groups compared to the control groups at 3 mo and 5 mo after operation. More importantly, there was a significant (P < 0.05) increase in c-Fos, caspase-3 and IL-1β expression in the model group rats at 3 mo compared to those at 5 mo after the operation (c-Fos: 11.20 ± 2.26 vs 27.68 ± 4.36 in the cervical cord, 11.3 ± 2.3 vs 29.3 ± 4.6 in the gastric antrum; caspase-3: 33.83 ± 3.71 vs 36.32 ± 4.01 in the cervical cord, 13.23 ± 3.21 vs 26.32 ± 4.01 in the gastric antrum; IL-1β: 42.06 ± 2.95 vs 45.91 ± 3.98 in the cervical cord, 26.56 ± 2.65 vs 32.01 ± 2.98 in the gastric antrum). Western blotanalysis showed time-dependent changes of caspase-3 and IL-1β protein in the cervical cord and gastric antrum of rats with cervical spondylosis; there was no significant expression of caspase-3 and IL-1β protein in the control group at 3 mo and 5 mo after the sham operation, whereas there was a significant difference in caspase-3 and IL-1β protein levels between the model group rats followed up for 3 mo and those for 5 mo (P < 0.05). CONCLUSION: There is a significant association of c-Fos, caspase-3 and IL-1β expressions in the gastric antrum with that in the spinal cord in rats with cervical spondylosis, suggesting that the gastrointestinal function may be affected by cervical spondylosis.

Research on Data Extraction and Analysis of Software Defect in IoT Communication Software

Software defect feature selection has problems of feature space dimensionality reduction and large search space.This research proposes a defect prediction feature selection framework based on improved shuffled frog leaping algorithm(ISFLA).Using the two-level structure of the framework and the improved hybrid leapfrog algorithm's own advantages,the feature values are sorted,and some features with high correlation are selected to avoid other heuristic algorithms in the defect prediction that are easy to produce local The case where the convergence rate of the optimal or parameter optimization process is relatively slow.The framework improves generalization of predictions of unknown data samples and enhances the ability to search for features related to learning tasks.At the same time,this framework further reduces the dimension of the feature space.After the contrast simulation experiment with other common defect prediction methods,we used the actual test data set to verify the framework for multiple iterations on Internet of Things(IoT)system platform.The experimental results show that the software defect prediction feature selection framework based on ISFLA is very effective in defect prediction of IoT communication software.This framework can save the testing time of IoT communication software,effectively improve the performance of software defect prediction,and ensure the software quality.

Improvement of characteristics of an InGaN light-emitting diode by using a staggered AlGaN electron-blocking layer

The optical and physical properties of an InGaN light-emitting diode （LED） with a specific design of a staggered AlGaN electron-blocking layer （EBL） are investigated numerically in detail. The electrostatic field distribution, energy band, carrier concentration, electroluminescence （EL） intensity, internal quantum efficiency （IQE）, and the output power are simulated. The results reveal that this specific design has a remarkable improvement in optical performance compared with the design of a conventional LED. The lower electron leakage current, higher hole injection efficiency, and consequently mitigated efficiency droop are achieved. The significant decrease of electrostatic field at the interface between the last barrier and the EBL of the LED could be one of the main reasons for these improvements.

Transport of velocity alignment particles in random obstacles

We numerically investigate the trapping behaviors of aligning particles in two-dimensional （2D） random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, particles are in trapped state. In this paper, we examine how the system parameters affect the trapping behaviors. At the large self-propelled speed, the ability of nematic particles escape from trapping state is enhancing rapidly, in the meanwhile the polar and free particles are still in trapped state. For the small rotation diffusion coefficient, the polar particles circle around （like vortices） the obstacles and here particles are in trapped state. Interestingly, only the partial nematic particles are trapped in the confined direction and additional particles remain flowing. In the free case, the disorder particle-particle collisions impede the motion in each other＇s directions, leading the free particles to be trapped. At the large rotation diffusion coefficient, the ordered motion of aligning particles disappear, particles fill the sample evenly and are self-trapped around obstacles. As the particles approach the trapping density due to the crowding effect the particles become so dense that they impede each other＇s motion. With the increasing number of obstacles, the trajectories of particles are blocked by obstacles, which obstruct the movement of particles. It is worth noting that when the number of the obstacles are large enough, once the particles are trapped, the system is permanently absorbed into a trapped state.