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Data-Driven Method for Predicting Remaining Useful Life of Bearings Based on Multi-Layer Perception Neural Network and Bidirectional Long Short-Term Memory Network
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作者 Yongfeng Tai Xingyu Yan +3 位作者 Xiangyi Geng Lin Mu Mingshun Jiang Faye Zhang 《Structural Durability & Health Monitoring》 2025年第2期365-383,共19页
The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee.In engineering scenarios,only a small amount of bearing performance degradation data can be obtained through acceler... The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee.In engineering scenarios,only a small amount of bearing performance degradation data can be obtained through accelerated life testing.In the absence of lifetime data,the hidden long-term correlation between performance degradation data is challenging to mine effectively,which is the main factor that restricts the prediction precision and engineering application of the residual life prediction method.To address this problem,a novel method based on the multi-layer perception neural network and bidirectional long short-term memory network is proposed.Firstly,a nonlinear health indicator(HI)calculation method based on kernel principal component analysis(KPCA)and exponential weighted moving average(EWMA)is designed.Then,using the raw vibration data and HI,a multi-layer perceptron(MLP)neural network is trained to further calculate the HI of the online bearing in real time.Furthermore,The bidirectional long short-term memory model(BiLSTM)optimized by particle swarm optimization(PSO)is used to mine the time series features of HI and predict the remaining service life.Performance verification experiments and comparative experiments are carried out on the XJTU-SY bearing open dataset.The research results indicate that this method has an excellent ability to predict future HI and remaining life. 展开更多
关键词 Remaining useful life prediction rolling bearing health indicator construction multilayer perceptron bidirectional long short-term memory network
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Short-Term Household Load Forecasting Based on Attention Mechanism and CNN-ICPSO-LSTM 被引量:1
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作者 Lin Ma Liyong Wang +5 位作者 Shuang Zeng Yutong Zhao Chang Liu Heng Zhang Qiong Wu Hongbo Ren 《Energy Engineering》 EI 2024年第6期1473-1493,共21页
Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a s... Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a single prediction model is hard to capture temporal features effectively, resulting in diminished predictionaccuracy. In this study, a hybrid deep learning framework that integrates attention mechanism, convolution neuralnetwork (CNN), improved chaotic particle swarm optimization (ICPSO), and long short-term memory (LSTM), isproposed for short-term household load forecasting. Firstly, the CNN model is employed to extract features fromthe original data, enhancing the quality of data features. Subsequently, the moving average method is used for datapreprocessing, followed by the application of the LSTM network to predict the processed data. Moreover, the ICPSOalgorithm is introduced to optimize the parameters of LSTM, aimed at boosting the model’s running speed andaccuracy. Finally, the attention mechanism is employed to optimize the output value of LSTM, effectively addressinginformation loss in LSTM induced by lengthy sequences and further elevating prediction accuracy. According tothe numerical analysis, the accuracy and effectiveness of the proposed hybrid model have been verified. It canexplore data features adeptly, achieving superior prediction accuracy compared to other forecasting methods forthe household load exhibiting significant fluctuations across different seasons. 展开更多
关键词 short-term household load forecasting long short-term memory network attention mechanism hybrid deep learning framework
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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Exploring the Interplay of Land Use Transformation and Its Environmental Impacts:A Case Study of Sonipat District,Haryana 被引量:1
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作者 Niraj Kumar Tejbir Singh Rana Subhash Anand 《Journal of Environmental & Earth Sciences》 2025年第2期76-88,共13页
Land use transformations in Sonipat District,Haryana,driven by urbanization,industrialization,and land acquisitions,have posed significant ecological and socio-economic challenges,particularly concerning food security... Land use transformations in Sonipat District,Haryana,driven by urbanization,industrialization,and land acquisitions,have posed significant ecological and socio-economic challenges,particularly concerning food security.This study investigates the interplay between these land use changes and their environmental implications at macro(district)and micro(village)levels,focusing on agricultural productivity and resource sustainability.The study employs a mixed-method approach,integrating secondary data from official datasets and primary data gathered through structured household surveys,focus group discussions,and visual analysis techniques.Data from 20 villages,selected based on predominant land use characteristics,were analysed using statistical and geospatial tools,including ArcGIS and STATA,to quantify food grain losses and evaluate environmental degradation.Findings of this study reveal a 19%reduction in agricultural land over two decades(2000-2024),correlating with increased residential and industrial areas.Groundwater resources face severe overexploitation,with pollution from industrial clusters further degrading water and soil quality.The study estimates a total food grain loss of 1.5 million kilograms across surveyed villages due to land acquisitions.A strong positive correlation(R^(2)=0.98)between land acquisition and food loss underscores the direct impact of urbanization on agricultural output.The research underscores the urgency of sustainable land management practices,including preserving agricultural lands,optimizing groundwater usage,and enhancing community involvement in planning.By addressing these challenges,the study advocates for balanced urban expansion and food security to ensure ecological and economic resilience in the region. 展开更多
关键词 Environmental Impacts Food Security Land Acquisition Land use URBANIZATION
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Split nitrogen application increases maize root growth,yield,and nitrogen use efficiency under soil warming conditions 被引量:2
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作者 Zhenqing Xia Yuxiang Gong +3 位作者 Xiangyue Lyu Junchen Lin Yi Yang Haidong Lu 《The Crop Journal》 2025年第2期565-575,共11页
The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e... The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress. 展开更多
关键词 Maize(Zea mays L.) Soil warming Split nitrogen application Root growth Nitrogen use efficiency Grain yield
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Research on Short-Term Electric Load Forecasting Using IWOA CNN-BiLSTM-TPA Model
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作者 MEI Tong-da SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 北大核心 2025年第1期179-187,共9页
Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devi... Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devices have made power load data increasingly complex and volatile.This places higher demands on the prediction and analysis of power loads.In order to improve the prediction accuracy of short-term power load,a CNN-BiLSTMTPA short-term power prediction model based on the Improved Whale Optimization Algorithm(IWOA)with mixed strategies was proposed.Firstly,the model combined the Convolutional Neural Network(CNN)with the Bidirectional Long Short-Term Memory Network(BiLSTM)to fully extract the spatio-temporal characteristics of the load data itself.Then,the Temporal Pattern Attention(TPA)mechanism was introduced into the CNN-BiLSTM model to automatically assign corresponding weights to the hidden states of the BiLSTM.This allowed the model to differentiate the importance of load sequences at different time intervals.At the same time,in order to solve the problem of the difficulties of selecting the parameters of the temporal model,and the poor global search ability of the whale algorithm,which is easy to fall into the local optimization,the whale algorithm(IWOA)was optimized by using the hybrid strategy of Tent chaos mapping and Levy flight strategy,so as to better search the parameters of the model.In this experiment,the real load data of a region in Zhejiang was taken as an example to analyze,and the prediction accuracy(R2)of the proposed method reached 98.83%.Compared with the prediction models such as BP,WOA-CNN-BiLSTM,SSA-CNN-BiLSTM,CNN-BiGRU-Attention,etc.,the experimental results showed that the model proposed in this study has a higher prediction accuracy. 展开更多
关键词 Whale Optimization Algorithm Convolutional Neural Network Long short-term Memory Temporal Pattern Attention Power load forecasting
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Remaining useful life probabilistic prognostics using a novel dual adaptive sliding-window hybrid strategy
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作者 Run DONG Wenjie LIU Weilin LI 《Chinese Journal of Aeronautics》 2025年第7期408-421,共14页
The reliable,rapid,and accurate Remaining Useful Life(RUL)prognostics of aircraft power supply and distribution system are essential for enhancing the reliability and stability of system and reducing the life-cycle co... The reliable,rapid,and accurate Remaining Useful Life(RUL)prognostics of aircraft power supply and distribution system are essential for enhancing the reliability and stability of system and reducing the life-cycle costs.To achieve the reliable,rapid,and accurate RUL prognostics,the balance between accuracy and computational burden deserves more attention.In addition,the uncertainty is intrinsically present in RUL prognostic process.Due to the limitation of the uncertainty quantification,the point-wise prognostics strategy is not trustworthy.A Dual Adaptive Sliding-window Hybrid(DASH)RUL probabilistic prognostics strategy is proposed to tackle these deficiencies.The DASH strategy contains two adaptive mechanisms,the adaptive Long Short-Term Memory-Polynomial Regression(LSTM-PR)hybrid prognostics mechanism and the adaptive sliding-window Kernel Density Estimation(KDE)probabilistic prognostics mechanism.Owing to the dual adaptive mechanisms,the DASH strategy can achieve the balance between accuracy and computational burden and obtain the trustworthy probabilistic prognostics.Based on the degradation dataset of aircraft electromagnetic contactors,the superiority of DASH strategy is validated.In terms of probabilistic,point-wise and integrated prognostics performance,the proposed strategy increases by 66.89%,81.73% and 25.84%on average compared with the baseline methods and their variants. 展开更多
关键词 Remaining useful Life(RUL) Prognostics and Health Management(PHM) Probabilistic prognostics Long short-term Memory(LSTM) Kernel Density Estimation(KDE) ADAPTIVE Sliding window
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Analysis on the Use of Special Use Level of Antibiotics among Inpatients in a Hospital
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作者 Yufen XIA Wen PENG +2 位作者 Fan FENG Liang YANG Ying LIN 《Agricultural Biotechnology》 2025年第1期53-56,61,共5页
[Objectives]This study was conducted to promote the rational use of special use level of antibiotics in clinic and delay the emergence of drug resistance.[Methods]The application of antibiotics for special use among i... [Objectives]This study was conducted to promote the rational use of special use level of antibiotics in clinic and delay the emergence of drug resistance.[Methods]The application of antibiotics for special use among inpatients of a hospital in 2019 was analyzed.The data in the drug information management system of the hospital were queried,and the collected expert consultation records of special-use antibiotics were sorted out.Indicators including the use rate of special-use antibiotics,antibiotic use density(AUD),defined daily dose system(DDDs)and defined daily dose system cost(DDDc)of each drug,the annual pathogen detection rate,disease distribution and pathogenic microorganism detection were summarized and analyzed for inpatients in the hospital retrospectively.[Results]In 2019,the average annual use rate of special-use antibiotics in the hospital was 1.53%,and the average annual use density was 1.59 DDDs.The antibiotics with the top three DDDs were imipenem and cilastatin,meropenem and cefepime.The antibiotics with the top three DDDc were voriconazole dispersible tablets,voriconazole for injection,and meropenem for injection.The average annual detection rate of microorganisms was 85.77%.The diseases were mainly diagnosed as respiratory infections such as pneumonia and secondary infections after radiotherapy and chemotherapy before medication,and the detected pathogens were mainly Candida and its subspecies,Escherichia coli,and Klebsiella and its subspecies.[Conclusions]The clinical use of special-use antibiotics in the hospital was basically reasonable,but there were still some problems.It is necessary to increase management efforts,strengthen training for relevant medical personnel,and provide management ideas for further standardizing the use of antibiotics in the hospital. 展开更多
关键词 ANTIBIOTICS Special use level Rational use of drugs Antibiotic use density Defined daily dose system Microbial inspection
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Impact of land use change on carbon storage in the middle reaches of the Yellow River,China 被引量:1
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作者 SHI Xiaoliang ZHANG Jie +4 位作者 LIU Simin DING Hao CHEN Xi WANG Li ZHANG Dan 《Journal of Arid Land》 2025年第2期167-181,共15页
The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,c... The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,causing carbon storage exchanges.However,the relationship between carbon storage and land use change in the MRYR is not concerned,which results in the uncertainty in the simulation of carbon storage in this area.Land use changes directly affect the carbon storage capacity of ecosystems,and as an indicator reflecting the overall state of land use,land use degree has an important relationship with carbon storage.In this study,land use data and the integrated valuation of ecosystem services and trade-offs(InVEST)model were used to assess the trends in land use degree and carbon storage in the MRYR during 1980-2020.The potential impact index and the standard deviation ellipse(SDE)algorithm were applied to quantify and analyze the characteristics of the impact of land use changes on carbon storage.Subsequently,land use transitions that led to carbon storage variations and their spatial variations were determined.The results showed that:(1)the most significant periods of carbon storage changes and land use transitions were observed during 1990-1995 and 1995-2020,with the most changed areas locating in the east of Fenhe River and in northwestern Henan Province;(2)the positive impact of land use degree on carbon storage may be related to the environmental protection measures implemented along the Yellow River,while the negative impact may be associated with the expansion of construction land in plain areas;and(3)the conversion of other land use types to grassland was the primary factor affecting carbon storage changes during 1980-2020.In future land use planning,attention should be given to the direction of grassland conversion,and focus on reasonably limiting the development of construction land.To enhance carbon storage,it will be crucial to increase the area of high-carbon-density land types,such as forest land and grassland under the condition that the area of permanent farmland does not decrease. 展开更多
关键词 carbon storage land use degree integrated valuation of ecosystem services and trade-offs(InVEST)model potential impact standard deviation ellipse(SDE)
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Septic shock due to cytomegalovirus colitis associated with rituximab use:A case report
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作者 Siddharth Patel Jordan Jay +2 位作者 Prutha Pathak Mc Anto Antony Mrudula Thiriveedi 《World Journal of Virology》 2025年第1期118-123,共6页
BACKGROUND Cytomegalovirus(CMV)infections can cause significant morbidity and mortality in immunocompromised individuals.CMV targets dysfunctional lymphocytes.Chronic rituximab(RTX)therapy can cause B-lymphocyte dysfu... BACKGROUND Cytomegalovirus(CMV)infections can cause significant morbidity and mortality in immunocompromised individuals.CMV targets dysfunctional lymphocytes.Chronic rituximab(RTX)therapy can cause B-lymphocyte dysfunction,increasing CMV risk.Rarely,CMV infections present with critical illness such as septic shock.CASE SUMMARY A 64-year-old African American woman presented with generalized weakness and non-bloody watery diarrhea of 4-6 weeks duration.She did not have nausea,vomiting or,abdominal pain.She had been on monthly RTX infusions for neuromyelitis optica.She was admitted for septic shock due to pancolitis.Blood investigations suggested pancytopenia and serology detected significantly elevated CMV DNA.Valganciclovir treatment led to disease resolution.CONCLUSION This case illustrates an extremely rare case of CMV colitis associated with RTX use presenting with septic shock.High suspicion for rare opportunistic infections is imperative in individuals with long-term RTX use. 展开更多
关键词 Cytomegalovirus colitis Rituximab use Immunocompromised status Septic shock PANCYTOPENIA Case report
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Short-term efficacy of laparoscopic radical resection for colorectal cancer and risk of unplanned reoperation after surgery
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作者 Wen-Bin Li Jiang Li +1 位作者 Wei Yu Jian-Hua Gao 《World Journal of Gastrointestinal Surgery》 2025年第4期140-149,共10页
BACKGROUND Surgery is the first choice of treatment for patients with colorectal cancer.Traditional open surgery imparts great damage to the body of the patient and can easily cause adverse stress reactions.With the c... BACKGROUND Surgery is the first choice of treatment for patients with colorectal cancer.Traditional open surgery imparts great damage to the body of the patient and can easily cause adverse stress reactions.With the continuous development of medical technology,laparoscopic minimally invasive surgery has shown great advantages for the treatment of patients with celiac disease.AIM To investigate the short-term efficacy of laparoscopic radical surgery and traditional laparotomy for the treatment of colorectal cancer,and the differences in the risk analysis of unplanned reoperation after operation.METHODS As the research subjects,this study selected 100 patients with colorectal cancer who received surgical treatment at the Yulin First Hospital from January 2018 to January 2022.Among them,50 patients who underwent laparoscopic radical resection were selected as the research group and 50 patients who underwent traditional laparotomy were selected as the control group.Data pertaining to clinical indexes,gastrointestinal hormones,nutrition indexes,the levels of inflammatory factors,quality of life,Visual Analog Scale score,and the postoperative complications of the two groups of patients before and after treatment were collected,and the therapeutic effects in the two groups were analyzed and compared.RESULTS Compared with the control group,perioperative bleeding,peristalsis recovery time,and hospital stays were significantly shorter in the research group.After surgery,the levels of gastrin(GAS)and motilin(MTL)were decreased in both groups,and the fluctuation range of GAS and MTL observed in the research group was significantly lower than that recorded in the control group.The hemoglobin(Hb)levels increased after surgery,and the level of Hb in the research group was significantly higher compared with the control group.After the operation,the expression levels of tumor necrosis factor-α,interleukin-6,and C-reactive protein and the total incidence of complications were significantly lower in the research group compared with the control group.One year after the operation,the quality of life of the two groups was greatly improved,with the quality of life in the research group being significantly better.CONCLUSION Laparoscopy was effective for colorectal surgery by reducing the occurrence of complications and inflammatory stress reaction;moreover,the quality of life of patients was significantly improved,which warrants further promotion. 展开更多
关键词 Colorectal cancer Laparoscopic surgery LAPAROTOMY short-term efficacy Complications
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Association between Mental Distress and Weight-Related Self-Stigma via Problematic Social Media and Smartphone Use among Malaysian University Students: An Application of the Interaction of Person-Affect-CognitionExecution (I-PACE) Model
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作者 Wan Ying Gan Wei-Leng Chin +10 位作者 Shih-Wei Huang Serene En Hui Tung Ling Jun Lee Wai Chuen Poon Yan Li Siaw Kerry S.O’Brien Iqbal Pramukti Kamolthip Ruckwongpatr Jung-Sheng Chen Mark D.Griffiths Chung-Ying Lin 《International Journal of Mental Health Promotion》 2025年第3期319-331,共13页
Background:Weight-related self-stigma(WRSS)is prevalent among individuals with different types of weight status and is associated with a range of negative health outcomes.Social support and coping models explain how i... Background:Weight-related self-stigma(WRSS)is prevalent among individuals with different types of weight status and is associated with a range of negative health outcomes.Social support and coping models explain how individuals may use different coping methods to deal with their mental health needs.Psychological distress(e.g.,depression and stress)could lead to overuse of social media and smartphones.When using social media or smartphones,individuals are likely to be exposed to negative comments regarding weight/shape/size posted on the social media.Consequently,individuals who experience problematic social media use(PSMU)or problematic smartphone use(PSPU)may develop WRSS.Therefore,the present study examined the roles of PSMU and PSPU as mediators in the relationship between psychological distress and WRSS.Methods:Using convenience sampling via an online survey,622 participants with a mean age of 23.70 years(SD=4.33)completed questions assessing sociodemographic variables,psychological distress,PSMU,PSPU,WRSS,and self-reported weight and height.Results:The hierarchical regression models showed that sex(β=0.08,p=0.01),BMI(β=0.39,p<0.001),depression(β=0.21,p=0.001),stress(β=0.18,p=0.01),PSMU(β=0.09,p=0.045),and PSPU(β=0.14,p=0.001)were significant factors for WRSS.Conclusion:The mediation models showed that both PSMU and PSPU were significant mediators in the relationships between depression and stress with WRSS.The present findings provide some evidence for understanding WRSS and has important implications for developing interventions to reduce its negative impact on individuals’health and well-being. 展开更多
关键词 Weight-related self-stigma stress coping theory I-PACE model depression stress social media use smartphone use
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Land use/cover change and ecological network in Gansu Province,China during 2000-2020 and their simulations in 2050 被引量:1
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作者 MA Xinshu XIN Cunlin +6 位作者 CHEN Ning XIN Shunjie CHEN Hongxiang ZHANG Bo KANG Ligang WANG Yu JIAO Jirong 《Journal of Arid Land》 2025年第1期43-57,共15页
Land use/cover change(LUCC)constitutes the spatial and temporal patterns of ecological security,and the construction of ecological networks is an effective way to ensure ecological security.Exploring the spatial and t... Land use/cover change(LUCC)constitutes the spatial and temporal patterns of ecological security,and the construction of ecological networks is an effective way to ensure ecological security.Exploring the spatial and temporal change characteristics of ecological network and analyzing the integrated relationship between LUCC and ecological security are crucial for ensuring regional ecological security.Gansu is one of the provinces with fragile ecological environment in China,and rapid changes in land use patterns in recent decades have threatened ecological security.Therefore,taking Gansu Province as the study area,this study simulated its land use pattern in 2050 using patch-generating land use simulation(PLUS)model based on the LUCC trend from 2000 to 2020 and integrated the LUCC into morphological spatial pattern analysis(MSPA)to identify ecological sources and extract the ecological corridors to construct ecological network using circuit theory.The results revealed that,according to the prediction results in 2050,the areas of cultivated land,forest land,grassland,water body,construction land,and unused land would be 63,447.52,39,510.80,148,115.18,4605.21,8368.89,and 161,752.40 km^(2),respectively.The number of ecological sources in Gansu Province would increase to 80,with a total area of 99,927.18 km^(2).The number of ecological corridors would increase to 191,with an estimated total length of 6120.66 km.Both ecological sources and ecological corridors showed a sparse distribution in the northwest and dense distribution in the southeast of the province at the spatial scale.The number of ecological pinch points would reach 312 and the total area would expect to increase to 842.84 km^(2),with the most pronounced increase in the Longdong region.Compared with 2020,the number and area of ecological barriers in 2050 would decrease significantly by 63 and 370.71 km^(2),respectively.In general,based on the prediction results,the connectivity of ecological network of Gansu Province would increase in 2050.To achieve the predicted ecological network in 2050,emphasis should be placed on the protection of cultivated land and ecological land,the establishment of ecological sources in desert areas,the reinforcement of the protection for existing ecological sources,and the construction of ecological corridors to enhance the stability of ecological network.This study provides valuable theoretical support and references for the future construction of ecological networks and regional land resource management decision-making. 展开更多
关键词 patch-generating land use simulation(PLUS)model morphological spatial pattern analysis(MSPA) circuit theory ecological source ecological resistance surface ecological corridor ecological pinch point
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Viscous Flow Activation Energy and Short-Term Aging Resistance of SBS-Modified Asphalt Enhanced by PPA Oil-Grinding Activated MoS_(2)
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作者 Shun Chen Yingjie Wang +7 位作者 Xingyang He Ying Su Yingyuan Pan Yimin Cao Wentian Wang Chao Yang Bo Jiang Shaolin Zhang 《Fluid Dynamics & Materials Processing》 2025年第2期387-404,共18页
Styrene-butadiene-styrene(SBS)modified asphalt(SA)has long found effective applications in road construction materials.When combined with fillers,SBS-modified asphalt has demonstrated promising resistance to fatigue c... Styrene-butadiene-styrene(SBS)modified asphalt(SA)has long found effective applications in road construction materials.When combined with fillers,SBS-modified asphalt has demonstrated promising resistance to fatigue cracking caused by temperature fluctuations and aging.In this study,molybdenum disulfide(MoS_(2))and polyphosphoric acid(PPA)were ground in naphthenic oil(NO)and subjected to mechanical activation to create PPAmodified MoS_(2),referred to as OMS-PPA.By blending various ratios of OMS-PPA with SBS-modified asphalt,composite-modified asphalts were successfully developed to enhance their overall properties.To assess the mechanical characteristics and stability of these modified asphalts,various methods were employed,including penetration factor,flow activation energy,fluorescence microscopy,and dynamic shear rheology.Additionally,the short-term aging performance was evaluated using Fourier transform infrared(FTIR)spectroscopy and nanoindentation tests.The results revealed a 3.7%decrease in the penetration-temperature coefficient for SAOMS compared to SA,while 1-SA-OMS-PPA showed an even greater reduction of 7.1%.Furthermore,after short-term aging,carboxyl group generation in SA increased by 5.93%,while SA-OMS exhibited a smaller rise of 1.36%,and 1-SA-OMS-PPA saw an increase of just 0.93%.The study also highlighted significant improvements in the hardness of these materials.The hardness change ratio for SA-OMS decreased by 43.08%,while the ratio for 1-SA-OMS-PPA saw a notable reduction of 65.16% compared to unmodified SA.These findings suggest that OMS-PPA contributed to improvements in temperature sensitivity,particle dispersibility,and resistance to shortterm aging in asphalts.The results hold significant promise for the future development of advanced asphalt-based materials with potential high-value applications in flexible pavements for highways. 展开更多
关键词 Composite-modified asphalt GRINDING viscous flow activation energy short-term aging collaborated
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Association between the subclinical level of problematic internet use and habenula volume:a look at mediation effect of neuroticism
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作者 Halwa Zakia Yusuke Kyuragi +6 位作者 Qi Dai Naoya Oishi Yuzuki Ishikawa Lichang Yao Morio Aki Toshiya Murai Hironobu Fujiwara 《General Psychiatry》 2025年第1期26-34,共9页
Background Ongoing debates question the harm of internet use with the evolving technology,as many individuals transition from regular to problematic internet use(PIU).The habenula(Hb),located between the thalamus and ... Background Ongoing debates question the harm of internet use with the evolving technology,as many individuals transition from regular to problematic internet use(PIU).The habenula(Hb),located between the thalamus and the third ventricle,is implicated in various psychiatric disorders.In addition,personality features have been suggested to play a role in the pathophysiology of PIU.Aims This study aimed to investigate Hb volumetry in individuals with subclinical PIU and the mediating effect of personality traits on this relationship.Methods 110 healthy adults in this cross-sectional study underwent structural magnetic resonance imaging.Hb segmentation was performed using a deep learning technique.The Internet Addiction Test(IAT)and the NEO Five-Factor Inventory were used to assess the PIU level and personality,respectively.Partial Spearman's correlation analyses were performed to explore the reiationships between Hb volumetry,IAT and NEO.Multiple regression analysis was applied to identify personality traits that predict IAT scores.The significant trait was then treated as a mediator between Hb volume and IAT correlation in mediation analysis with a bootstrap value of 5000.Results Relative Hb volume was negatively correlated with IAT scores(partial rho=-0.142,p=0.009).The IAT score was positively correlated with neuroticism(partial rho=0.430,p<0.001)and negatively correlated with extraversion,agreeableness and conscientiousness(partial rho=-0.213,p<0.001;partial rho=-0.279,p<0.001;and partial rho=-0.327,p<0.001).There was a significant indirect effect of Hb volume on this model(β=-0.061,p=0.048,boot 95%confidence interval:-0.149 to-0.001).Conclusions This study uncovered a crucial link between reduced Hb volume and heightened PIU.Our findings highlight neuroticism as a key risk factor for developing PIU.Moreover,neuroticism was shown to mediate the relationship between Hb volume and PIU tendency,offering valuable insight into the complexities of this interaction. 展开更多
关键词 internet use piu hb volumetry Mediation Effect Habenula Volume NEUROTICISM personality traits Subclinical Level Problematic Internet use
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The Association between Problematic Internet Use,Resilience,and Fatigue in First-Year Medical College Students in China:A Moderated Mediation Model
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作者 Xiumei Chen Xiaobing Lu +6 位作者 Yufu Ning Lifeng Wang Jeffrey H.Gamble Xianhe Chen Xingyong Jiang I-Hua Chen Peijin Lin 《International Journal of Mental Health Promotion》 2025年第1期51-63,共13页
Background:Resilience is crucial for medical college students to thrive in the highly stressful environment of medical education.However,the prevalence of problematic internet use(PIU)in this population may negatively... Background:Resilience is crucial for medical college students to thrive in the highly stressful environment of medical education.However,the prevalence of problematic internet use(PIU)in this population may negatively impact their resilience.This study investigated the influence of problematic online gaming(PG)and problematic social media use(PSMU)on the resilience of medical college students in China.Methods:A sample of 5075 first-year medical college students from four Chinese universities was studied.PG served as the independent variable,resilience as the dependent variable,fatigue as the mediator,and PSMU as the moderator.Structural equation modeling was conducted using LISREL 8.80.Additionally,a moderated mediation model was evaluated using the jAMM module in jamovi 2.6.13.Results:The study’s findings revealed significant negative correlations between resilience and the variables of PG,PSMU,and fatigue.Fatigue mediated the relationship between PG and resilience(B=−0.04,95%CI=[−0.05,−0.03]).PSMU moderated the direct relationship between PG and resilience with the interaction term PG×PSMU significant(B=−0.004,t=−6.501,p<0.001)and the first stage(PG→fatigue)of the mediation with PG×PSMU significant(B=0.055,t=8.351,p<0.001).The detrimental effects of PG on resilience were more pronounced among individuals with lower levels of PSMU.Conclusion:This study concluded that addressing PIU,particularly PG,is essential for fostering resilience in medical college students.While PSMU itself is maladaptive,the underlying social media engagement may serve a protective role through social support in mitigating the adverse effects of PG on resilience. 展开更多
关键词 Problematic internet use problematic online gaming problematic social media use FATIGUE RESILIENCE structural equation modeling conditional mediation
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Optimizing planting density to improve growth,yield and resource use efficiencies for winter oilseed rape under ridge-furrow film mulching
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作者 Xiaobo Gu Zhikai Cheng +5 位作者 Yadan Du Huanjie Cai Yupeng Li Yuannong Li Heng Fang Shikun Sun 《Journal of Integrative Agriculture》 2025年第10期3819-3837,共19页
Ridge-furrow film mulching has been widely used as a water-saving and yield-increasing planting pattern in arid and semiarid regions.Planting density is also a vitally important factor influencing crop yield,and the o... Ridge-furrow film mulching has been widely used as a water-saving and yield-increasing planting pattern in arid and semiarid regions.Planting density is also a vitally important factor influencing crop yield,and the optimal planting density will vary in different environments(such as ridge-furrow film mulching).How the combination of film mulching and planting density will affect the growth,physiology,yield,and water and radiation use efficiencies of winter oilseed rape is not clear yet.Therefore,a three-year field experiment was conducted from 2017 to 2020 to explore the responses of leaf chlorophyll(Chl)content,net photosynthetic rate(P_(n)),leaf area index(LAI),aboveground dry matter(ADM),root growth and distribution,yield,evapotranspiration(ET),water use efficiency(WUE),and radiation use efficiency(RUE)of winter oilseed rape to different film mulching patterns(F,ridge-furrow planting with plastic film mulching over the ridges;N,flat planting without mulching)and planting densities(LD,100,000 plants ha^(-1);MD,150,000 plants ha^(-1);HD,200,000 plants ha^(-1)).The results showed that the F treatments led to significantly greater leaf Chl contents,P_(n),LAI,and ADM,and a stronger root system than treatments without film mulching throughout the whole winter rapeseed growing seasons.Winter oilseed rape in the MD treatments had better physiological(leaf Chl contents and P_(n))and growth(LAI,ADM,taproot,and lateral root)conditions than in LD and HD at the late growth period after stem-elongation.Grain yield in FMD was the greatest,and it was significantly greater by 34.8-46.0%,6.7-9.6%,87.8-108.3%,38.7-50.3%,and 50.2-61.8%compared to those of FLD,FHD,NLD,NMD,and NHD,respectively.Furthermore,the ET in FMD was equivalent to FLD and FHD,but was markedly lower by 12.2-18.4%,14.5-20.3%,and 14.6-20.4%than in NLD,NMD,and NHD.Finally,the WUE and RUE in FMD were significantly improved by 88.5-94.0%and 29.0-41.8%compared to NHD(the local conventional planting pattern and planting density for winter rapeseed).In summary,FMD is a favorable cultivation management strategy to save water,increase yield and improve resource utilization efficiencies in winter oilseed rape in Northwest China. 展开更多
关键词 ridge-furrow film mulching crop growth and physiology YIELD EVAPOTRANSPIRATION water use efficiency radiation use efficiency
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Risk factors and clinical prediction models for short-term recurrence after endoscopic surgery in patients with colorectal polyps
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作者 Meng Zhang Rui Yin +3 位作者 Jie Ying Guan-Qi Liu Ping Wang Jian-Xin Ge 《World Journal of Gastrointestinal Surgery》 2025年第8期255-266,共12页
BACKGROUND Colorectal polyps(CPs)are important precursor lesions of colorectal cancer,and endoscopic surgery remains the primary treatment option.However,the shortterm recurrence rate post-surgery is high,and the risk... BACKGROUND Colorectal polyps(CPs)are important precursor lesions of colorectal cancer,and endoscopic surgery remains the primary treatment option.However,the shortterm recurrence rate post-surgery is high,and the risk factors for recurrence remain unknown.AIM To comprehensively explore risk factors for short-term recurrence of CPs after endoscopic surgery and develop a nomogram prediction model.METHODS Overall,362 patients who underwent endoscopic polypectomy between January 2022 and January 2024 at Nanjing Jiangbei Hospital were included.We screened basic demographic data,clinical and polyp characteristics,surgery-related information,and independent risk factors for CPs recurrence using univariate and multivariate logistic regression analyses.The multivariate analysis results were used to construct a nomogram prediction model,internally validated using Bootstrapping,with performance evaluated using area under the curve(AUC),calibration curve,and decision curve analysis.RESULTS CP re-occurred in 166(45.86%)of the 362 patients within 1 year post-surgery.Multivariate logistic regression analysis showed that age(OR=1.04,P=0.002),alcohol consumption(OR=2.07,P=0.012),Helicobacter pylori infection(OR=2.34,P<0.001),polyp number>2(OR=1.98,P=0.005),sessile polyps(OR=2.10,P=0.006),and adenomatous pathological type(OR=3.02,P<0.001)were independent risk factors for post-surgery recurrence.The nomogram prediction model showed good discriminatory(AUC=0.73)and calibrating power,and decision curve analysis showed that the model had good clinical benefit at risk probabilities>20%.CONCLUSION We identified multiple independent risk factors for short-term recurrence after endoscopic surgery.The nomogram prediction model showed a certain degree of differentiation,calibration,and potential clinical applicability. 展开更多
关键词 Colorectal polyps Endoscopic surgery RECURRENCE Risk factors Prediction models short-term
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Impact of Short-Term Power Shortage from Low Voltage Ride through and DC Commutation Failure on Power Grid Frequency Stability
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作者 Wenjia Zhang Sixuan Xu +2 位作者 Wanchun Qi Zhuyi Peng Wentao Sun 《Energy Engineering》 2025年第6期2371-2387,共17页
Countries worldwide are advocating for energy transition initiatives to promote the construction of low-carbon energy systems.The low voltage ride through(LVRT)characteristics of renewable energy units and commutation... Countries worldwide are advocating for energy transition initiatives to promote the construction of low-carbon energy systems.The low voltage ride through(LVRT)characteristics of renewable energy units and commutation failures in line commutated converter high voltage direct current(LCC-HVDC)systems at the receiving end leads to short-term power shortage(STPS),which differs from traditional frequency stability issues.STPS occurs during the generator’s power angle swing phase,before the governor responds,and is on a timescale that is not related to primary frequency regulation.This paper addresses these challenges by examining the impact of LVRT on voltage stability,developing a frequency response model to analyze the mechanism of frequency instability caused by STPS,deriving the impact of STPS on the maximum frequency deviation,and introducing an energy deficiency factor to assess its impact on regional frequency stability.The East China Power Grid is used as a case study,where the energy deficiency factor is calculated to validate the proposed mechanism.STPS is mainly compensated by the rotor kinetic energy of the generators in this region,with minimal impact on other regions.It is concluded that the energy deficiency factor provides an effective explanation for the spatial distribution of the impact of STPS on system frequency. 展开更多
关键词 Commutation failure frequency stability LVRT renewable energy short-term power shortage LCCHVDC
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Short-term post-COVID-19 symptoms in 21,012 patients:a cross-sectional study
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作者 Lujia Cao Xiaolei Wu +17 位作者 Chenyao Zhang Chuanchi Wang Wenliang Lyu Li Liu Wei Liu Zhimin Yang Yan Shi Shuguang Yu Candong Li Ming Yang Xing Yan Xinyao Jin Hui Wang Wenke Zheng Bo Pang Wentai Pang Jingqing Hu Junhua Zhang 《Acupuncture and Herbal Medicine》 2025年第3期291-300,共10页
Objectives:This study aimed to clarify the short-term symptoms,duration,and influencing factors in people recovering from coronavirus disease 2019(COVID-19)after China’s dynamic zero-COVID-19 policy was implemented i... Objectives:This study aimed to clarify the short-term symptoms,duration,and influencing factors in people recovering from coronavirus disease 2019(COVID-19)after China’s dynamic zero-COVID-19 policy was implemented in December 2022.Methods:We included data from a large-scale on-line survey conducted in China between January 14 and February 1,2023.Participants were individuals of all ages.Chi-squared tests and multivariate logistic regression analyses were performed to identify factors associated with different symptoms.Results:Overall,21,012 patients from seven regions of China were included in this study(female:71.22%).For most patients,the period from symptom onset to a negative nucleic acid test result was≤10 days(72.33%).The distribution of symptoms varied at different times,with respiratory(1-4 weeks)and psychocardiology(5-8 weeks)symptoms being the most common.Multivariate analysis identified male sex,no comorbidity,and living in northeast and northwest China(compared with central China)as independent factors associated with a lower risk of symptoms,while age(41-60 years)was a possible risk factor(compared with 18-40 years).Conclusions:Short-term respiratory and psychocardiology symptoms were the most common after COVID-19 recovery.Sex,age,geographical region,and comorbidities were potential influencing factors for the development of short-term symptoms. 展开更多
关键词 China COVID-19 Influencing factors Negative nucleic acid test short-term symptoms
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