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Existence of hidden attractors in nonlinear hydro-turbine governing systems and its stability analysis
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作者 赵鹏翀 卫皓娟 +3 位作者 徐振坤 陈帝伊 许贝贝 王雨萌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期220-228,共9页
This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The param... This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The parameter switching algorithm is used to numerically study the dynamic behaviors of the system.Moreover,it is investigated that for some parameters the system with a stable equilibrium point can generate strange hidden attractors.A self-excited attractor with the change of its parameters is also recognized.In addition,numerical simulations are carried out to analyze the dynamic behaviors of the proposed system by using the Lyapunov exponent spectra,Lyapunov dimensions,bifurcation diagrams,phase space orbits,and basins of attraction.Consequently,the findings in this work show that the basins of hidden attractors are tiny for which the standard computational procedure for localization is unavailable.These simulation results are conducive to better understanding of hidden chaotic attractors in higher-dimensional dynamical systems,and are also of great significance in revealing chaotic oscillations such as uncontrolled speed adjustment in the operation of hydropower station due to small changes of initial values. 展开更多
关键词 nonlinear hydro-turbine governing systems hidden attractors basin of attraction Lyapunov exponent spectrum
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Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations
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作者 Longfei Chen Zhibin He +7 位作者 Wenzhi Zhao Xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan Gao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期189-204,共16页
Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental changes.However,as a principal silvicult... Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental changes.However,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning intensity.Thinning significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on Ra.The temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) dynamics.Thinning increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial activity.Our results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term thinning.Therefore,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) emissions.The increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions. 展开更多
关键词 Heterotrophic respiration Autotrophic respiration long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity
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Long-Term Performance and Microstructural Characterization of Dam Concrete in the Three Gorges Project
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作者 Chen Lyu Cheng Yu +3 位作者 Chao Lu Li Pan Wenwei Li Jiaping Liu 《Engineering》 SCIE EI CAS CSCD 2024年第2期237-262,共26页
This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled ... This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam.The mechanical properties of the laboratory dam concrete,whether cured in natural or standard environments,continued to improve over time.Furthermore,the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years.However,curing and long-term exposure to the local natural environment reduced the frost resistance.Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash(FA)particles were almost fully hydrated to form compact micro structures consisting of large quantities of homogeneous calcium(alumino)silicate hydrate(C-(A)-S-H)gels and a few crystals.No obvious interfacial transition zones were observed in the microstructure owing to the longterm pozzolanic reaction.This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete.A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age.The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity,indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks.In this study,both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure,which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years.Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface.Therefore,the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution and development of its properties. 展开更多
关键词 Three Gorges Dam long-term performance Microstructural analysis Moderate-heat cement Fly ash
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Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China
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作者 Xinlei Fu Yunze Dai +3 位作者 Jun Cui Pengfei Deng Wei Fan Xiaoniu Xu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期95-108,共14页
Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have no... Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition. 展开更多
关键词 long-term nitrogen addition Old-growth subtropical forest METAGENOMICS Beneficial microorganisms Co-occurrence network
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Research on Risk Identification and Industrial Governance of Digital Education Products Based on Data Annotation Technology
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作者 Tong Lili Zeng Jia +1 位作者 Di Ying Wang Nan 《China Communications》 SCIE CSCD 2024年第3期273-282,共10页
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 pen... 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”. 展开更多
关键词 digital education products industry governance risk identification
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Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital
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作者 Mu-Han Li Ge-Chong Ruan +9 位作者 Wei-Xun Zhou Xiao-Qing Li Sheng-Yu Zhang Yang Chen Xiao-Yin Bai Hong Yang Yu-Jie Zhang Peng-Yu Zhao Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2523-2537,共15页
BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis an... BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications. 展开更多
关键词 Autoimmune enteropathy Clinical manifestations Diagnostic criteria Pathological features long-term prognosis
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Do companies influenced by smart cities pay more attention to green governance?Mechanism and optimal spatial correlation
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作者 Xiaoxu Guo Rao Zhang Yue Zhang 《Chinese Journal of Population,Resources and Environment》 2024年第1期48-57,共10页
Smart cities are a way for China to construct an innovative and environmentally conscious nation.The paper examines the impact of smart cities on corporate green governance and provides a theoretical foundation for fo... Smart cities are a way for China to construct an innovative and environmentally conscious nation.The paper examines the impact of smart cities on corporate green governance and provides a theoretical foundation for formulating and executing smart city policy in China.Based on panel data from Chinese A-share listed companies in Shanghai and Shenzhen from 2008 to 2020,this study constructs a multiperiod double-difference model to examine the influence of smart cities on corporate green governance.Additionally,it uses a spatial double-difference model to investigate the spatial spillover effect of smart cities on neighboring areas.The findings indicate that smart cities effectively enhance corporate green governance.Analyzing the influencing mechanisms reveals that resource allocation efficiency,technological innovation,management environmental awareness,and regional environmental enforcement efforts act as mediators.Furthermore,the study reveals that the impact of smart cities on promoting corporate green governance is more pronounced in regions with lower levels of marketization and resource-based cities.Moreover,the research explores the spatial spillover effects of smart cities,with an effective radius of approximately 350 km.The optimal spatial correlation zone for green governance of businesses in neighboring areas in relation to smart cities is within a range of 250-350 km.This is manifested by the significant promotion of green governance in neighboring area businesses facilitated by smart cities. 展开更多
关键词 Smart cities Corporate green governance Mediating effects Spatial associations
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Research on the Collaborative Governance of Social Responsibility in Online Audiovisual Enterprises
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作者 Chuying Kang Muhammad Zaffwan Idris Juan Liu 《Social Networking》 2024年第1期1-13,共13页
This paper aims to analyze the present conditions of the social responsibility ecosystem in online audiovisual enterprises in the digital age. It focuses on the governance of social responsibility in these enterprises... This paper aims to analyze the present conditions of the social responsibility ecosystem in online audiovisual enterprises in the digital age. It focuses on the governance of social responsibility in these enterprises and conducts an in-depth analysis of the problems and influencing factors related to the social responsibility aberrations of online audiovisual enterprises. Drawing upon social responsibility theory and collaborative governance theory, this research constructs a social responsibility guidance and governance system guided by the public, supported by the voluntary fulfillment of responsibilities by online audiovisual enterprises, and based on the collaborative participation of diverse stakeholders. It explores and optimizes the implementation pathways of this system, providing theoretical support and practical guidance for promoting the sustainable development of online audiovisual enterprises. Furthermore, it aims to contribute to the creation of a harmonious Internet ecosystem. 展开更多
关键词 Online Audiovisual Enterprises Social Responsibility Collaborative governance
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Enhancing transboundary natural tourism resources governance:unveiling the spatial pattern and its influencing factors
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作者 ZHANG Shengrui ZHANG Tongyan +1 位作者 JU Hongrun WANG Yingjie 《Journal of Mountain Science》 SCIE CSCD 2024年第3期973-986,共14页
Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensi... Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensive database of transboundary natural tourism resources(TNTR)through amalgamation of diverse data sources.Utilizing the Getis-Ord Gi^(*),kernel density estimation,and geographical detectors,we scrutinize the spatial patterns of TNTR,focusing on both named and unnamed entities,while exploring the influencing factors.Our findings reveal 7883 identified TNTR in China,with mountain tourism resources emerging as the predominant type.Among provinces,Hunan boasts the highest count,while Shanghai exhibits the lowest.Southern China demonstrates a pronounced clustering trend in TNTR distribution,with the spatial arrangement of biological landscapes appearing more random compared to geological and water landscapes.Western China,characterized by intricate terrain,exhibits fewer TNTR,concurrently unveiling a significant presence of unnamed natural tourism resources.Crucially,administrative segmentation influences TNTR development,generating disparities in regional goals,developmental stages and intensities,and management approaches.In response to these variations,we advocate for strengthening the naming of the unnamed transboundary tourism resources,constructing a geographic database of TNTR for government and establishing a collaborative management mechanism based on TNTR database.Our research contributes to elucidating the intricate landscape of TNTR,offering insights for tailored governance strategies in the realm of cross-provincial tourism resource management. 展开更多
关键词 Transboundary natural tourism resources(TNTR) Spatial difference Spatial autocorrelation governance optimization China
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Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts
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作者 Yi-Fan Lv Bing Zhu +8 位作者 Ming-Ming Meng Yi-Fan Wu Cheng-Bin Dong Yu Zhang Bo-Wen Liu Shao-Li You Sa Lv Yong-Ping Yang Fu-Quan Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期491-502,共12页
BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there hav... BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ascites.However,there have been no specific studies on predicting long-term survival after TIPS placement.AIM To establish a model to predict long-term survival in patients with hepatitis cirrhosis after TIPS.METHODS A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS implantation.Through univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after TIPS.Consequently,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)level.Furthermore,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing models.RESULTS The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS placement.The NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation cohorts.Additionally,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients and guide follow-up management after TIPS implantation. 展开更多
关键词 Transjugular intrahepatic portosystemic shunt long-term survival Predictive model
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Protocol to study the effects of AMPK-mTOR/PINK-Parkin dual signaling pathways on the formation of coronary heart disease showing blood stasis symptom pattern based on traditional Chinese medicine theory of“heart governing blood and vessels”
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作者 An-Ni Chen Man-Li Zhou +4 位作者 Yun-Feng Yu Kang-Yan Tang Lin-Juan Yang Mo-Fei Shi Wei-Xiong Jian 《Aging Communications》 2023年第3期18-22,共5页
In this study,we aim to combine gene transfection techniques with the modeling methods previously employed by the research group to deeply investigate the corresponding theories of traditional Chinese medicine regard... In this study,we aim to combine gene transfection techniques with the modeling methods previously employed by the research group to deeply investigate the corresponding theories of traditional Chinese medicine regarding“myocardial energy metabolism”and“aortic thrombosis”.Our goal is to elucidate the biological mechanism underlying the occurrence and development of coronary heart disease with blood stasis syndrome from the perspectives of“heart and vessels”and“Qi(in traditional Chinese medicine,it refers to the most fundamental and subtle substances that constitute the human body and maintain life activities.At the same time,it also has the meaning of physiological function.In terms of traditional Chinese medicine,Qi and different words are used together to express different meanings)and blood”.The research content is divided into four modules as follows:1.establishment of an animal model of coronary heart disease with blood stasis syndrome through fibrinogen overexpression.2.Investigation of the mitochondrial quality control system in coronary heart disease with blood stasis syndrome under fibrinogen overexpression.3.Study of platelet autophagy in coronary heart disease with blood stasis syndrome under fibrinogen overexpression.4.Examination of the relationship between the AMPK-mTOR pathway and metabolism in platelet autophagy of coronary heart disease with blood stasis syndrome under fibrinogen overexpression.Ninety-six Sprague Dawley rats will be randomly assigned to the following groups:control group,model group,fibrinogen group and adeno-associated virus group.All rats will undergo a 14-week model construction process,and modern molecular biology methods will be employed to evaluate the model and examine relevant research indicators.The obtained data will be analyzed according to a predefined statistical analysis plan. 展开更多
关键词 coronary heart disease with blood stasis syndrome heart governing blood and vessels AMPK-mTOR/PINK-Parkin energy metabolism platelet autophagy study protocol
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Long-Term Mortality of Children with Congenital Heart Disease Admitted to the Departmental University Hospital of Borgou/Alibori from 2011 to 2022
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作者 Serge Hugues Mahougnon Dohou Nicolas Hamondji Amegan +3 位作者 Ahmad Ibrahim Gérard Médétinmè Kpanidja Chabi Olaniran Alphonse Biaou Houétondji Léopold Codjo 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期166-186,共21页
Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitte... Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitted to the Departmental University Hospital of Borgou/Alibori (CHUD-B/A) from 2011 to 2022. Methods: This descriptive longitudinal study with analytical aims covered 11 years (April 1, 2011 to December 31, 2022). It consisted of a review of the records of children under 15 years of age with echocardiographically confirmed congenital heart disease. This was followed by an interview with the parents to assess the children’s current condition. Data were entered using Kobocollect software and analyzed using R Studio 4.2.2. software. Results: A total of 143 complete files were retained. The median age at diagnosis was 14 months (IIQ: Q1 = 4;Q3 = 60) with a range of 2 days and 175 months, and the sex-ratio (M/F) was 0.96. Left-to-right shunts were the most frequent cardiopathy group (62.9%). Only 35 children (24.5%) benefited from restorative treatment. The mortality rate was 31.5%. Median survival under the maximum bias assumption was 114 months and 216 months under the assumption of minimum bias. Survival was significantly better in children with right-to-left shunts (p = 0.0049) under the assumption of minimum bias. The death risk factors were: age at diagnosis less than 12 months (aHR = 7.58;95% CI = 3.36 - 17.24;p Conclusion: The long-term mortality of congenital heart disease is high and favoured by the absence of restorative treatment. Local correction of congenital heart disease and medical follow-up will help to reduce this mortality. 展开更多
关键词 Congenital Heart Disease long-term MORTALITY Parakou Risk Factors
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Long-term performance of recycled asphalt mixtures containing high RAP and RAS
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作者 Jiangmiao Yu Zengyao Lin +3 位作者 Guilian Zou Huayang Yu Zhen Leng Yuan Zhang 《Journal of Road Engineering》 2024年第1期36-53,共18页
The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents ... The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents of RAP and RAS in asphalt pavement may lead to durability issues,especially the fatigue cracking and thermal cracking.It is necessary to conduct a series of analyses on asphalt mixtures containing high RAP and RAS,and seek methods to enhance their long-term performance.This paper provides a comprehensive over-view of the long-term performance of recycled asphalt mixtures containing high contents of RAP and RAS.The findings in this research show that rutting resistance of high recycled asphalt mixtures is not a concern,whereas their resistance to fatigue and thermal cracking is not conclusive.Recycling agents can be used to improve the thermal cracking resistance of high recycled asphalt mixtures.An optimum decision on recycling agents will improve the durability properties of high recycled asphalt mixtures.It is recommended that to use a balanced mixture design approach with testing of the blended asphalt binders will provide better understanding of long-term performance of recycled asphalt mixtures containing high RAP and RAS. 展开更多
关键词 Recycled asphalt mixture Recycling agents long-term performance CRACKING
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Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection
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作者 Hong-Yi Zhu Jie Wu +7 位作者 Yuan-Miao Zhang Fang-Lan Li Jin Yang Bin Qin Jiong Jiang Ning Zhu Meng-Yao Chen Bai-Cang Zou 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1990-2005,共16页
BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological char... BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD.AIM To analyze the features of gastric mucosal tumors at different differentiation levels,and to explore the prognostic factors of ESD.METHODS We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021,according to the latest Japanese guidelines(sixth edition),and divided them into low-grade intrae-pithelial neoplasia(LGIN),high-grade intraepithelial neoplasia(HGIN),and computed tomography at 3,6 and 12 months after ESD.We compared clinicopathologic characteristics,ESD efficacy,and complications with different degrees of differentiation,and analyzed the related factors associated with ESD.RESULTS HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients(P<0.001)and accounted for more 0-IIc(P<0.001),atrophic gastritis was common(P<0.001),and irregular microvascular patterns(IMVPs)and demarcation lines(DLs)were more obvious(P<0.001).There was more infiltration in the undifferentiated carcinoma tissue(P<0.001),more abnormal folds and poorer mucosal peristalsis(P<0.001),and more obvious IMVPs,irregular microsurface patterns and DLs(P<0.05)than in the LGIN and HGIN tissues.The disease-free survival rates at 2,5,and 8 years after ESD were 95.0%,90.1%,and 86.9%,respectively.Undifferen-tiated lesions(HR 5.066),white moss(HR 7.187),incomplete resection(HR 3.658),and multiple primary cancers(HR 2.462)were significantly associated with poor prognosis.CONCLUSION Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics,which are closely related to the safety and efficacy of ESD. 展开更多
关键词 Gastric mucosal epithelial neoplasia Differentiated early gastric cancer Undifferentiated early gastric cancer Endoscopic submucosal dissection long-term outcomes
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Long-term outcomes after endoscopic removal of malignant colorectal polyps:Results from a 10-year cohort
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作者 Anna Fábián Renáta Bor +13 位作者 Béla Vasas Mónika Szűcs Tibor Tóth Zsófia Bősze Kata Judit Szántó Péter Bacsur Anita Bálint Bernadett Farkas Klaudia Farkas Ágnes Milassin Mariann Rutka Tamás Resál Tamás Molnár Zoltán Szepes 《World Journal of Gastrointestinal Endoscopy》 2024年第4期193-205,共13页
BACKGROUND Choosing an optimal post-polypectomy management strategy of malignant colorectal polyps is challenging,and evidence regarding a surveillance-only strategy is limited.AIM To evaluate long-term outcomes after... BACKGROUND Choosing an optimal post-polypectomy management strategy of malignant colorectal polyps is challenging,and evidence regarding a surveillance-only strategy is limited.AIM To evaluate long-term outcomes after endoscopic removal of malignant colorectal polyps.METHODS A single-center retrospective cohort study was conducted to evaluate outcomes after endoscopic removal of malignant colorectal polyps between 2010 and 2020.Residual disease rate and nodal metastases after secondary surgery and local and distant recurrence rate for those with at least 1 year of follow-up were invest-igated.Event rates for categorical variables and means for continuous variables with 95%confidence intervals were calculated,and Fisher’s exact test and Mann-Whitney test were performed.Potential risk factors of adverse outcomes were RESULTS In total,135 lesions(mean size:22.1 mm;location:42%rectal)from 129 patients(mean age:67.7 years;56%male)were enrolled.The proportion of pedunculated and non-pedunculated lesions was similar,with en bloc resection in 82%and 47%of lesions,respectively.Tumor differentiation,distance from resection margins,depth of submucosal invasion,lymphovascular invasion,and budding were reported at 89.6%,45.2%,58.5%,31.9%,and 25.2%,respectively.Residual tumor was found in 10 patients,and nodal metastasis was found in 4 of 41 patients who underwent secondary surgical resection.Univariate analysis identified piecemeal resection as a risk factor for residual malignancy(odds ratio:1.74;P=0.042).At least 1 year of follow-up was available for 117 lesions from 111 patients(mean follow-up period:5.59 years).Overall,54%,30%,30%,11%,and 16%of patients presented at the 1-year,3-year,5-year,7-year,and 9-10-year surveillance examinations.Adverse outcomes occurred in 9.0%(local recurrence and dissemination in 4 patients and 9 patients,respectively),with no difference between patients undergoing secondary surgery and surveillance only.CONCLUSION Reporting of histological features and adherence to surveillance colonoscopy needs improvement.Long-term adverse outcome rates might be higher than previously reported,irrespective of whether secondary surgery was performed. 展开更多
关键词 Malignant colorectal polyps T1 tumor Endoscopic removal OUTCOMES long-term SURVEILLANCE
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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions
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作者 Guo-Dong Cheng Xue-Yu Pang +4 位作者 Jin-Sheng Sun Zheng-Song Qiu Chuang-Chuang Wang Jian-Kun Qin Ning Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1122-1134,共13页
The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy... The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength retrogression.The addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems. 展开更多
关键词 Fly ash long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)
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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Coupling and Long-term Change Characteristics of Forest Carbon Sink and Forestry Economic Development in China
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作者 Ying ZHANG Na MENG Keren ZHANG 《Asian Agricultural Research》 2024年第7期1-11,共11页
[Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promo... [Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promote the development of green low-carbon economy in China.[Methods]Based on the data of six forest resource inventories from 1989 to 2018 and related studies,the comprehensive evaluation model of forest carbon sink and forestry economic development,the coupling degree model of forest carbon sink and forestry economic development,and the coupling coordination degree model of forest carbon sink and forestry economic development were adopted.The coupling degree of forest carbon sink and forestry economic development from 1992 to 2018 was analyzed.Stepwise regression and ARIMA model were used to analyze the influencing factors and lagging characteristics of forest carbon sink.The coupling degree between forest carbon sink and forestry economic development in China from 2019 to 2030 was predicted by autoregression and ADF test.The coupling between forest carbon sink and forestry economic development in China and its long-term change characteristics were also discussed in this study.[Results](i)The investment of ecological construction and protection,the actual investment of forestry key ecological projects,GDP and the import of forest products had a significant impact on forest resources carbon stock.The total output value of forestry industry,the actually completed investment of forestry key ecological projects and the export volume of forest products had a significant impact on the forest carbon sink,and the actually completed investment of forestry key ecological projects has the greatest impact on the two.(ii)The impact of actually completed investment of forestry key ecological projects had a lag of 2 years on the forest resources carbon stock and a lag of 1 year on the forest carbon sink.When investing in forest carbon sink,it is necessary to make a good plan in advance,and do a good job in forest resources management and time optimization.(iii)From 1992 to 2018,the coupling degree of forest resources carbon stock,forest carbon sink and long-term development of forestry economy in China was gradually increasing.Although there were some fluctuations in the middle time,the coupling degree of forest resources carbon stock and the long-term development of forestry economy increased by 9.24%annually,and the degree of coupling coordination increased from"serious imbalance"in 1992 to"high-quality coordination"in 2018.From 1993 to 2018,the coupling degree of forest carbon sink and long-term development of forestry economy increased by 9.63%annually,slightly faster than the coupling coordination degree of forest resources carbon stock and long-term development of forestry economy.The coordination level also rose from level 2 in 1993 to level 10 in 2018.(iv)The prediction shows that the coupling coordination degree of forest resources carbon stock,forest carbon sink and the long-term development of forestry economy would increase from 2019 to 2030.The coupling coordination degree(D)values of both were close to 1,the coordination level was also 10 for a long time,and the degree of coupling coordination was also maintained at the"high-quality coordination"level for a long time.[Conclusions]Forest has multiple benefits of society,economy and ecology,and forest carbon sink is only a benefit output.The long-term coupling analysis of forest carbon sink and forestry economic development is a key point to multiple benefit analysis.The analysis shows that the spillover effect and co-evolution effect of forest carbon sink in China are significant.From 1992 to 2018,the coupling coordination degree of forest carbon sink and forestry economic development was gradually rising.The prediction analysis also indicate that the coupling coordination degree between the forest carbon sink and the long-term development of forestry economy will remain at the level of"high-quality coordination"for a long time from 2019 to 2030.Therefore,improving the level of forest management and maintaining the current trend of increasing forest resources are the key to achieving the goal of carbon peaking and carbon neutrality in China. 展开更多
关键词 Forest resources carbon stock Forest carbon sink Coupling coordination degree Forestry economic development long-term trend
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Pseudoaneurysm formation following transarterial embolization of traumatic carotid-cavernous fistula with detachable balloon:An institutional cohort long-term study
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作者 Prasert Iampreechakul Korrapakc Wangtanaphat +5 位作者 Songpol Chuntaroj Yodkhwan Wattanasen Sunisa Hangsapruek Punjama Lertbutsayanukul Pimchanok Puthkhao Somkiet Siriwimonmas 《World Journal of Radiology》 2024年第4期94-108,共15页
BACKGROUND The goal of therapy for traumatic carotid-cavernous fistula(TCCF)is the elimination of fistula while maintaining patency of the parent artery.The treatment for TCCF has evolved from surgery to endovascular ... BACKGROUND The goal of therapy for traumatic carotid-cavernous fistula(TCCF)is the elimination of fistula while maintaining patency of the parent artery.The treatment for TCCF has evolved from surgery to endovascular management using detachable balloons,coils,liquid embolic agents,covered stents,or flow-diverter stent through arterial or venous approaches.Despite the withdrawal of detachable balloons from the market in the United States since 2004,transarterial embolization with detachable balloons has currently remained the best initial treatment for TCCF in several countries.However,the pseudoaneurysm formation following transarterial detachable balloon embolization has rarely been observed in long-term follow-up.AIM To determine the occurrence and long-term follow-up of pseudoaneurysm after transarterial detachable balloon for TCCF.METHODS Between January 2009 and December 2019,79 patients diagnosed with TCCF were treated using detachable latex balloons(GOLDBAL)of four sizes.Pseudoaneurysm sizes were stratified into five grades for analysis.Initial and follow-up assessments involved computed tomography angiography at 1 month,6 month,1 year,and longer intervals for significant cases.Clinical follow-ups occurred semi-annually for 2 years,then annually.Factors analyzed included sex,age,fistula size and location,and balloon size.RESULTS In our cohort of 79 patients treated for TCCF,pseudoaneurysms formed in 67.1%,with classifications ranging from grade 0 to grade 3;no grade 4 or giant pseudoaneurysms were observed.The majority of pseudoaneurysms did not progress in size,and some regressed spontaneously.Calcifications developed in most large pseudoaneurysms over 5-10 years.Parent artery occlusion occurred in 7.6%and recurrent fistulas in 16.5%.The primary risk factors for pseudoaneurysm formation were identified as the use of specific balloon sizes,with balloon SP and No.6 significantly associated with its occurrence(P=0.005 and P=0.002,respectively),whereas sex,age,fistula size,location,and the number of balloons used were not significant predictors.CONCLUSION Pseudoaneurysm formation following detachable balloon embolization for TCCF is common,primarily influenced by the size of the balloon used.Despite this,all patients with pseudoaneurysms remained asymptomatic during long-term follow-up. 展开更多
关键词 Pseudoaneurysm formation Traumatic carotid-cavernous fistula Direct carotid-cavernous fistula Transarterial embolization Detachable balloon Endovascular treatment Computed tomography angiography long-term follow-up
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Research on the Establishment of a Long-Term Care System for the Elderly with Alzheimer’s Disease Under the Background of Long-Term Care Insurance: A Literature Review
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作者 Wei Wang Faridah Mohd Said 《Journal of Clinical and Nursing Research》 2024年第5期348-355,共8页
With the aging of the country’s population structure,the problem of social pensions is becoming more and more serious.As for the issue of social pension,the elderly with Alzheimer’s disease are a special group,and t... With the aging of the country’s population structure,the problem of social pensions is becoming more and more serious.As for the issue of social pension,the elderly with Alzheimer’s disease are a special group,and the issue of care services for these elderly has attracted widespread attention from society.However,judging from the current level of social security provided to the elderly with dementia in the country,there is a serious imbalance between supply and demand.Therefore,this problem needs to be solved urgently and is of great significance for further improving the country’s social pension security system.Routine care is limited to hospitals and mainly focuses on the patient’s condition.Patients fail to receive comprehensive care services and the effect is not ideal.Therefore,in order to improve patients’cognitive function and quality of life,and learn from international experience,a“community-institution-home”three-dimensional linkage care model based on long-term care insurance can be established.The application of this model can effectively solve and further improve the country’s elderly care and social security system. 展开更多
关键词 long-term care insurance ELDERLY Alzheimer’s disease long-term care system
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