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Research on Risk Identification and Industrial Governance of Digital Education Products Based on Data Annotation Technology

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China Communications 2024年第3期21卷 273-282页

作者： Tong Lili Zeng jia Di ying Wang Nan Faculty of Education Beijing Normal University Beijing 100875China China Unicom Beijing 102211China

The social transformation brought aboutby digital technology is deeply impacting various industries.Digital education products, with core technologiessuch as 5G, AI, IoT (Internet of Things),etc., are continuously penetrating areas such as teaching,management, and evaluation. Apps, miniprograms,and emerging large-scale models are providingexcellent knowledge performance and flexiblecross-media output. However, they also exposerisks such as content discrimination and algorithmcommercialization. This paper conducts anevidence-based analysis of digital education productrisks from four dimensions: “digital resourcesinformationdissemination-algorithm design-cognitiveassessment”. It breaks through corresponding identificationtechnologies and, relying on the diverse characteristicsof governance systems, explores governancestrategies for digital education products from the threedomains of “regulators-developers-users”.

关键词： digital education products industry governance risk identification

Numerical Investigation on Heat Transfer Characteristics of Microencapsulated Phase Change Material Slurry in a Rectangular Minichannel

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Journal of Thermal Science 2024年第2期33卷 564-577页

作者： WANG Zhibin LI Zilong jia Lisi DING Bin CHEN ying School of Materials and Energy Guangdong University of TechnologyGuangzhou510006China Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter Guangzhou510006China College of New Energy China University of Petroleum(East China)Qingdao266580China

Microencapsulation phase change material slurry(MEPCMS) becomes a potential working fluid for cooling high energy density miniaturized components,thanks to the latent heat absorption of particles in the heat transfer process.In this work,the Discrete Phase Model(DPM) based on the Euler-Lagrangian method is used to numerically investigate the convective heat transfer characteristics of MEPCMS flowing through a rectangular minichannel with constant heat flux.The results show that particles of MEPCMS are mainly subjected to drag force during the flow.Even so,they can migrate from the high-temperature region to the low-temperature region driven by the thermophoretic force,affecting the particle distribution and phase change process.Moreover,the Nux of the MEPCMS fluctuates due to particle phase change with varying specific heat capacities.Specifically,the value increases first,then decreases,and eventually increases again until it approaches the fully developed value of the pure base fluid as the particles gradually melt.Furthermore,the heat transfer performance of the MEPCMS is influenced by the combination of fluid inlet temperature fluid inlet velocity(v),and mass concentration(c_(m)) of MEPCM particles.The result shows that the maximum reduction of the maximum bottom wall temperature difference(ΔT_(w)) is 23.98% at T_(in)=293.15 K,v=0.15 m·s^(-1),c_(m)=10%.

关键词： Microencapsulated Phase Change Material Slurry(MPCMS) Discrete Phase Model(DPM) particle-fluid interaction force minichannel heat sink thermophoresis

Postpartum quality of life and mental health in women with heart disease:Integrated clinical communication and treatment

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World Journal of Psychiatry 2024年第1期14卷 63-75页

作者： jia-Lin Liu Qi Wang Dong-ying Qu Department of Obstetrics and Gynecology China Medical UniversityShenyang 110122Liaoning ProvinceChina Department of Psychiatry General Hospital of Northern Theater CommandShenyang 110016Liaoning ProvinceChina Department of Obstetrics and Gynecology General Hospital of Northern Theater CommandShenyang 110016Liaoning ProvinceChina

BACKGROUND Postpartum quality of life(QoL)in women with heart disease has been neglected.AIM To improve clinical communication and treatment,we integrated medical data and subjective characteristics to study postpartum QoL concerns.METHODS The study assessed QoL 6 wk after birth using the 12-Item Short-Form Health Survey.The Edinburgh Postnatal Depression Scale,Cardiac Anxiety Questionnaire,European Heart Failure Self-Care Behavior Scale,and a self-designed questionnaire based on earlier research were also used to assess patient characteristics.Patient data were collected.Prediction models were created using multiple linear regression.RESULTS This retrospective study examined postpartum QoL in 105 cardiac patients.Postpartum QoL scores were lower(90.69±13.82)than those of women without heart disease,with physical component scores(41.09±9.91)lower than mental component scores(49.60±14.87).Postpartum depression(33.3%),moderate anxiety(37.14%),pregnancy concerns(57.14%),offspring heart problems(57.14%),and life expectancy worries(48.6%)were all prevalent.No previous cardiac surgery,multiparity,higher sadness and cardiac anxiety,and fear of unfavorable pregnancy outcomes were strongly related to lower QoL(R^(2)=0.525).CONCLUSION Postpartum QoL is linked to physical and mental health in women with heart disease.Our study emphasizes the need for healthcare workers to recognize the unique characteristics of these women while developing and implementing comprehensive management approaches during their maternity care.

关键词： Heart disease Pregnancy Postpartum Quality of life Mental health

Enhanced photocatalytic performance by regulating the Ce^(3+)/Ce^(4+)ratio in cerium dioxide

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 75-87页

作者： Zhi Li Dongsheng jia Wei Zhang ying Li Mitang Wang Dongliang Zhang School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai200093China

Cerium dioxide(CeO_(2))photocatalysts are used in treating environmental pollution and addressing the energy crisis due to their excellent oxygen storage capacities and abundant oxygen vacancies.In this paper,CeO_(2)precursors were synthesized with different water-alcohol ratios via a solvothermal method,and CeO_(2)photocatalysts with different Ce^(3+)/Ce^(4+)ratios were obtained by changing the precursor calcination atmospheres(air,Ar)as well as the calcination time.The effects of CeO_(2)with different Ce^(3+)/Ce^(4+)ratios in photocatalytic degradations of methylene blue under visible light were investigated.X-ray photoelectron spectroscopy results showed that the surfaces of the samples calcined under Ar had higher Ce^(3+)/Ce^(4+)ratios and oxygen vacancy concentrations,which reduced the band gaps of the catalysts and improved their utilization of visible light.In addition,the many Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies on the sample surfaces improved the separation and transfer efficiencies of the photogenerated carriers.The sample C2-Ar calcined under Ar showed a high adsorption capacity and excellent photocatalytic activity by removing 96%of the methylene blue within 120 min,which was more than twice the degradation rate of the sample(C2-air)prepared via calcination under air.Trapping experiments showed that photogenerated holes played a key role in the photocatalytic process.In addition,a synergistic photocatalytic mechanism for the Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies was elucidated in detail,and the sensitization of cerium dioxide by dyes aided the degradation of methylene blue.

关键词： CeO_(2) oxygen vacancies Ce^(3+)/Ce^(4+)ratios photocatalytic dye-sensitization

A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage Linear Feature Calibration

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： Yong-Chao Li Rui-Sheng jia ying-Xiang Hu Hong-Mei Sun the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation metrics.In this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised information.For this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the network.Specifically,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd images.In addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density estimation.The experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of Shanghai Tech Part A,ShanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

Effects of dietary intervention on human diseases:molecular mechanisms and therapeutic potential

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1389-1422页

作者： Yu-Ling Xiao Yue Gong ying-jia Qi Zhi-Ming Shao Yi-Zhou jiang Key Laboratory of Breast Cancer in Shanghai Department of Breast SurgeryFudan University Shanghai Cancer CenterShanghaiChina Department of Oncology Shanghai Medical CollegeFudanUniversityShanghai200032China

Diet,serving as a vital source of nutrients,exerts a profound influence on human health and disease progression.Recently,dietary interventions have emerged as promising adjunctive treatment strategies not only for cancer but also for neurodegenerative diseases,autoimmune diseases,cardiovascular diseases,and metabolic disorders.These interventions have demonstrated substantial potential in modulating metabolism,disease trajectory,and therapeutic responses.Metabolic reprogramming is a hallmark of malignant progression,and a deeper understanding of this phenomenon in tumors and its effects on immune regulation is a significant challenge that impedes cancer eradication.Dietary intake,as a key environmental factor,can influence tumor metabolism.Emerging evidence indicates that dietary interventions might affect the nutrient availability in tumors,thereby increasing the efficacy of cancer treatments.However,the intricate interplay between dietary interventions and the pathogenesis of cancer and other diseases is complex.Despite encouraging results,the mechanisms underlying diet-based therapeutic strategies remain largely unexplored,often resulting in underutilization in disease management.In this review,we aim to illuminate the potential effects of various dietary interventions,including calorie restriction,fasting-mimicking diet,ketogenic diet,protein restriction diet,high-salt diet,high-fat diet,and high-fiber diet,on cancer and the aforementioned diseases.We explore the multifaceted impacts of these dietary interventions,encompassing their immunomodulatory effects,other biological impacts,and underlying molecular mechanisms.This review offers valuable insights into the potential application of these dietary interventions as adjunctive therapies in disease management.

关键词： diseases metabolism potential

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 100-113页

作者： Chao Wang ying Liu Mingze Wu jia Li ying Feng Xianjin Ning Hong Li Ningfei Wang Baolu Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized propellants.The microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/mol.The laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and combustion.Moreover,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

关键词： Micro-aluminum powder(μAl) Nano-sized alloy coating Combustion catalyst Ammonium perchlorate Pyrolysis behavior Ignition and combustion

Remediation of di(2-ethylhexyl)phthalate(DEHP)contaminated black soil by freeze-thaw aging biochar

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Journal of Environmental Sciences 2024年第1期135卷 681-692页

作者： Lei Wang Zeyu Dou Chaoran Ma Xiaochen jia Hongye Wang Wenjing Bao Lei Wang jianhua Qu ying Zhang School of Resources and Environment Northeast Agricultural UniversityHarbin 150030China

Di(2-ethylhexyl)phthalate(DEHP),a complex structure with high toxicity,is a common organic pollutant.This study investigated the effects of fresh biochar(FBC),and freeze-thaw cycled aged biochar(FTC-BC)on DEHP-contaminated soils using a pot experiment.The specific surface area of FBC increased from 145.20 to 303.50 m~2/g,and oxygen-containing functional groups increased from 1.26 to 1.48 mol/g after freeze-thaw cycles,greatly enhancing the adsorption of DEHP by biochar in the soil.The comprehensive radar chart evaluation showed that FBC and FTC-BC reduced DEHP growth stress and improved the soil properties.Compared with FBC,FTC-BC performed better in protecting the normal growth of pakchoi and improving soil properties.In addition,the application of biochar increased the diversity and abundance of bacteria in the DEHP-contaminated soil and changed the composition of the soil bacterial community.The partial least squares path model(PLS-PM)showed that adding biochar as a soil remediation agent significantly positively impacted soil nutrients and indirectly reduced the DEHP levels in soil and plants by increasing soil microbial diversity.Compared with FBC,FTC-BC creates a more satisfactory living environment for microorganisms and has a better effect on the degradation of DEHP in the soil.This study provides a theoretical basis for future biochar remediation of DEHP-contaminated soils in cold high-latitude regions.

关键词： DEHP Freeze-thaw cycles Biochar Soil restoration

Surface-induced Microstructure and Performance Changes in P3HT Ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： Hong-Tao Shan jia-Xin He Bing-Yan Zhu Xue-Ting Cao ying-ying Yan jian-Jun Zhou Hong Huo Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68L)on glass,Si wafers and indium tin oxide(ITO)substrates.The electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was used.Moreover,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to ITO.Combining grazing-incidence wide-angle X-ray diffraction(GIXRD),UV-visible(UV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ITO.Finally,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different substrates.Our work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is chosen.These findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances