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Cross-Sectional Online Survey on Depression and Anxiety Among the Population Infected or Non-Infected with COVID-19——China,December 2022

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China CDC weekly 2023年第11期5卷 235-240页

作者： Tingting Qin Xingming Li Mingyu Gu Yao Wang Yutong Yang Xinyuan Bai Kun Qiao School of Public Health Capital Medical UniversityBeijingChina

Summary What is already known about this topic?The psychological impact of the large-scale infection of the population resulting from the end of lockdown measures in China during the coronavirus disease 2019(COVID-19)pandemic is unknown.What is added by this report?Among all participants,55.7%had depression symptoms,with a significant difference between the infected and non-infected groups,and 30.1%had anxiety.Those who were young,unvaccinated,had lower incomes,and experienced chronic diseases were more likely to experience negative emotions.What are the implications for public health practice?Government officials should take into account the effect of policies on public sentiment during similar public health events and implement tailored community interventions to address any negative sentiment.

关键词： Infect likely Population

Sea surface wind speed retrieval from Sentinel-1 HH polarization data using conventional and neural network methods

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Acta Oceanologica Sinica 2021年第1期40卷 13-21页

作者： Tingting Qin Tong Jia Qian Feng Xiaoming Li College of Surveying Mapping and GeoinformationGuilin University of TechnologyGuilin 541006China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Beijing 101408China Key Laboratory of Space Ocean Remote Sensing and Applications National Satellite Ocean Application ServiceBeijing 100081China

Conventional retrieval and neural network methods are used simultaneously to retrieve sea surface wind speed(SSWS)from HH-polarized Sentinel-1(S1)SAR images.The Polarization Ratio(PR)models combined with the CMOD5.N Geophysical Model Function(GMF)is used for SSWS retrieval from the HH-polarized SAR data.We compared different PR models developed based on previous C-band SAR data in HH-polarization for their applications to the S1 SAR data.The recently proposed CMODH,i.e.,retrieving SSWS directly from the HHpolarized S1 data is also validated.The results indicate that the CMODH model performs better than results achieved using the PR models.We proposed a neural network method based on the backward propagation(BP)neural network to retrieve SSWS from the S1 HH-polarized data.The SSWS retrieved using the BP neural network model agrees better with the buoy measurements and ASCAT dataset than the results achieved using the conventional methods.Compared to the buoy measurements,the bias,root mean square error(RMSE)and scatter index(SI)of wind speed retrieved by the BP neural network model are 0.10 m/s,1.38 m/s and 19.85%,respectively,while compared to the ASCAT dataset the three parameters of training set are–0.01 m/s,1.33 m/s and 15.10%,respectively.It is suggested that the BP neural network model has a potential application in retrieving SSWS from Sentinel-1 images acquired at HH-polarization.

关键词： Sentinel-1 HH-polarization sea surface wind speed retrieval methods

Molecular design for enhanced spin transport in molecular semiconductors

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Nano Research 2023年第12期16卷 13457-13473页

作者： tingting Yang Yang qin Xianrong Gu Xiangnan Sun Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Molecular semiconductors(MSCs),characterized by a longer spin lifetime than most of other materials due to their weak spin relaxation mechanisms,especially at room temperature,together with their abundant chemical tailorability and flexibility,are regarded as promising candidates for spintronic applications.Molecular spintronics,as an emerging subject that utilizes the unique properties of MSCs to study spin-dependent phenomena and properties,has attracted wide attention.In molecular spintronic devices,MSCs play the role as medium for information transport,process,and storage,in which the efficient spin inject–transport process is the prerequisite.Herein,we focus mainly on summarizing and discussing the recent advances in theoretical principles towards spin transport of MSCs in terms of the injection of spin-polarized carriers through the ferromagnetic metal/MSC interface and the subsequent transport within the MSC layer.Based on the theoretical progress,we cautiously present targeted design strategies of MSCs that contribute to the optimization of spin-transport efficiency and give favorable approaches to exploring accessional possibilities of spintronic materials.Finally,challenges and prospects regarding current spin transport are also presented,aiming to promote the development and application of the rosy and energetic field of molecular spintronics.

关键词： molecular spintronics molecular semiconductors spin transport spin injection molecular design

Exchanges,Mutual Learning and Looking Forward to the Future The Exhibition of Oil Paintings of China and Five Central Asian Countries

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China & The World Cultural Exchange 2024年第3期 28-33页

作者： qin tingting 不详

Exchanges and mutual learning between the Chinese and foreign civilizations are an important part of human cultural development.The Chinese civilization adopts an all-embracing,open and inclusive attitude to understand the different views of different civilizations on the connotation of values.The ancient Silk Road has opened a new window of friendship between countries and written a new chapter in the development of mankind.

关键词： Looking mutual civilization

Item-level Forecasting for E-commerce Demand with High-dimensional Data Using a Two-stage Feature Selection Algorithm

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Journal of Systems Science and Systems Engineering 2022年第2期31卷 247-264页

作者： Hongyan Dai qin Xiao Nina Yan Xun Xu tingting Tong Business School Central University of Finance and EconomicsBeijing 100081China Department of Management Operationsand MarketingCollege of Business AdministrationCalifornia State UniversityStanislausTurlockCA95382United States Institute of Supply Chain Analytics&International Business College Dongbei University of Finance and EconomicsDalian 116025China

With the rapid development of information technology and fast growth of Internet users,e-commerce nowadays is facing complex business environment and accumulating large-volume and highdimensional data.This brings two challenges for demand forecasting.First,e-merchants need to find appropriate approaches to leverage the large amount of data and extract forecast features to capture various factors affecting the demand.Second,they need to efficiently identify the most important features to improve the forecast accuracy and better understand the key drivers for demand changes.To solve these challenges,this study conducts a multi-dimensional feature engineering by constructing five feature categories including historical demand,price,page view,reviews,and competition for e-commerce demand forecasting on item-level.We then propose a two-stage random forest-based feature selection algorithm to effectively identify the important features from the high-dimensional feature set and avoid overfittlng.We test our proposed algorithm with a large-scale dataset from the largest e-commerce platform in China.The numerical results from 21,111 items and 109 million sales observations show that our proposed random forest-based forecasting framework with a two-stage feature selection algorithm delivers 11.58%,5.81%and 3.68%forecast accuracy improvement,compared with the Autoregressive Integrated Moving Average(ARIMA),Random Forecast,and Random Forecast with one-stage feature selection approach,respectively,which are widely used in literature and industry.This study provides a useful tool for the practitioners to forecast demands and sheds lights on the B2C e-commerce operations management.

关键词： Forecasting e-commerce high-dimensional feature feature selection

Non-layer-transformed Mn_(3)O_(4) cathode unlocks optimal aqueous magnesium-ion storage via synergizing amorphous ion channels and grain refinement

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Journal of Energy Chemistry 2022年第5期31卷 42-48页

作者： Zhongyu Pan Tingting Qin Wei Zhang Xianyu Chu Taowen Dong Nailin Yue Zizhun Wang Weitao Zheng State Key Laboratory of Automotive Simulation and Control School of Materials Science&EngineeringKey Laboratory of Mobile Materials MOEElectron Microscopy Centerand International Center of Future ScienceJilin UniversityChangchun 130012JilinChina

Aqueous rechargeable magnesium ion batteries(ARMBs) have obtained more attention due to the twoelectrons transfer nature, low cost and safety. However, the scarcity of cathode materials seriously hinders the development of ARMBs because of the unfavorable strong interaction between Mg^(2+) and cathode material. Herein, we choose a pre-treated spinel Mn_(3)O_(4) cathode for aqueous Mg^(2+) storage. The pretreatment in Na_(2)SO_(4) solution induces the grain refinement decorated with tortuous amorphous ion diffusion channels, facilitating the production of electrochemical reaction active sites and the diffusion of Mg^(2+), respectively, which achieve a(sub-)surface pseudocapacitance reaction between Mn(Ⅱ) and Mn(Ⅲ). As a result, the pre-treated Mn_(3)O_(4) cathode exhibits a package of optimal performances, i.e., a capacity of 98.9 m Ah g^(-1) and a high capacity retention rate of 99.4% after 2000 cycles. To the best of our knowledge, our work not only provides a new reaction mechanism of spinelMn_(3)O_(4) in aqueous batteries system,but also affords a high cycle stability electrode material for rechargeable Mg^(2+) energy storage.

关键词： Spinel Mn3O4 Grain refinement Amorphous ARMBs

Optimization of MAC algorithm based on IEEE 802.15.4 in indoor positioning system

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High Technology Letters 2021年第1期27卷 86-94页

作者：孙冠宇 qin Danyang Lan tingting Key Laboratory of Electronic and Communication Engineering Heilongjiang UniversityHarbin 150080P.R.China

The mobility of the targets asks for high requirements of the locating speed in indoor positioning systems.The standard medium access control(MAC)algorithm will often cause lots of packet conflicts and high transmission delay if multiple users communicate with one beacon at the same time,which will severely limit the speed of the system.Therefore,an optimized MAC algorithm is proposed based on channel reservation to enable users to reserve beacons.A frame threshold is set to ensure the users with shorter data frames do not depend on the reservation mechanism,and multiple users can achieve packets switching with relative beacon in a fixed sequence by using frequency division multiplexing technology.The simulation results show that the optimized MAC algorithm proposed in this paper can improve the positioning speed significantly while maintaining the positioning accuracy.Moreover,the positioning accuracy can be increased to a certain extent if more channel resources can be obtained,so as to provide effective technical support for the location and tracking applications of indoor moving targets.

关键词： medium access control(MAC)algorithm indoor positioning multi-channel fingerprint identification IEEE 802.15.4

Doping Gd^(3+)Ion in PDA-PHBV Coating on Ti6Al4V Alloy for Enhancing Corrosion Resistance and Proliferation of Human Gingival Fibroblasts and Human Umbilical Vein Endothelial Cells

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 812-824页

作者： Sijie qin Xiongcheng Xu Yanjin Lu Liu Li tingting Huang Jinxin Lin Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China College of Chemistry Fuzhou UniversityFuzhou350108China Research Center of Oral Tissue Engineering School and Hospital of StomatologyFujian Medical UniversityFuzhou350001China

In this study,we fabricated poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV)coatings doped with Gd^(3+)(1,5,and 10×10^(−4) mol/L)on Ti6Al4V alloy for the first time to promote soft tissue sealing around dental implants.The corrosion resistance of Gd^(3+)-modified PHBV-coated Ti6Al4V was studied by electrochemical and immersion tests,respectively,whereas CCK-8 and RT-PCR evaluated the biocompatibility to human gingival fibroblasts(HGFs)and human umbilical vein endothelial cells(HUVECs).It was found that the Gd^(3+)-modified PHBV coating could enhance the corrosion resistance of Ti6Al4V.In vitro cell tests showed that PHBV coatings with and without Gd^(3+) addition could promote adhesion and proliferation of HGFs and HUVECs,showing a Gd^(3+) content-dependent manner.Moreover,it was found that the PDA-PHBV@1Gd showed the best proliferation to HGFs by up-regulating gene expressions of VINCULIN,ITGB1,and ITGA3,whereas the best response to HUVECs with the highest gene expression of eNOS and HIF-1αgenes was found in the PDA-PHBV@5Gd-coated group.

关键词： Soft tissue sealing Poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV) Gd^(3+) Corrosion resistance Human gingival fibroblasts

Myosin regulates intracellular force and guides collective cancer cell migration via the FAK-Rho/ROCK feedback loop

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Genes & Diseases 2023年第6期10卷 2199-2201页

作者： Xiang qin Yuchen He Yixi Zhang Shun Li tingting Li Fengming You Yiyao Liu Department of Pharmacy Personalized Drug Therapy Key Laboratory of Sichuan ProvinceSichuan Provincial People's HospitalSchool of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengduSichuan 611731China TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province Hospital of Chengdu University of Traditional Chinese MedicineChengduSichuan 610072China

Breast cancerhas been one of the biggest killers of women due to its susceptibility and high metastasis.Pathological observations show that malignant cancer cells frequently invade the surrounding normal tissue in collective rather than individual cell migration.1,2 For individual cell migration,it has been found that the Rho/ROCK signaling is upregulated and correlates with disease progression.3 Meanwhile,Rho activates myosin-ll and the actomyosin-mediated contraction creates tension within the cells.4,5 However,the roles of the activation of the Rho/RoCK signal pathway in collective cell migration and the precise mechanisms by which myosin-ll fine-tunes the contractility of the cells to allow for the reorganization of the cytoskeleton that drives collective cell migration,remain unclear.This study investigated whether the high cellular contractility could activate the inside-out signal transductions and how did the intracellular force contribute to the collective cell migration.

关键词： cancer collective migration