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Imperative for long-term management and surveillance in Kawasaki disease
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作者 Yan Pan Fu-Yong Jiao 《World Journal of Clinical Cases》 SCIE 2025年第4期61-63,共3页
Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD pat... Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical Cases.This editorial emphasizes the critical need for long-term management and regular surveillance to prevent such complications.By drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures. 展开更多
关键词 Kawasaki disease long-term management Coronary artery aneurysm SURVEILLANCE Preventive care
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Study on "Borrowing Scenery under the Guidance of Emotion" in Chinese Landscape Architecture 被引量:1
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作者 薛晓飞 《Journal of Landscape Research》 2010年第11期73-76,共4页
One of the main theories of "borrowing scenery" which was "borrowing scenery under the guidance of emotion" was expounded from two aspects.And the second aspect was emphasized,that is,integrating s... One of the main theories of "borrowing scenery" which was "borrowing scenery under the guidance of emotion" was expounded from two aspects.And the second aspect was emphasized,that is,integrating social beauty into natural beauty so as to produce artistic beauty of landscape,and layer beauty was the main content manifested in Chinese landscape garden. 展开更多
关键词 LANDSCAPE architecture borrowing SCENERY "borrowing SCENERY under the GUIDANCE of emotion"
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Chinese Borrowings in English
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作者 鞠丽丽 《科技视界》 2014年第28期179-180,共2页
There are eight types of English word formation, which are widely used nowadays in English. Among them, Borrowings, as one of widely used types of English word formation, has drawn people's attention because many ... There are eight types of English word formation, which are widely used nowadays in English. Among them, Borrowings, as one of widely used types of English word formation, has drawn people's attention because many English words are borrowed from other languages, such as German, Latin. This article aims to demonstrate Chinese Borrowings in English from two aspects. 展开更多
关键词 英语学习 学习方法 阅读知识 阅读材料
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Geliable Lexical Borrowings in China English on the Internet 被引量:1
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作者 付雪芬 程金花 《海外英语》 2012年第21期256-258,共3页
Lexical borrowing in China English is an important part of English localization.This paper,on the basis of the study of vogue lexical English expressions on the Internet,tries to describe and explain the characteristi... Lexical borrowing in China English is an important part of English localization.This paper,on the basis of the study of vogue lexical English expressions on the Internet,tries to describe and explain the characteristics of lexical borrowings in China English on the Internet. 展开更多
关键词 LEXICAL borrowing China ENGLISH INTERNET
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STUDY ON THE INTERRELATION BETWEEN THE FOREIGN ELEMENTS AND THE NATIVE ELEMENT IN ENGLISH——English Borrowings from Chinese
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作者 邹凌冰 《湘潭师范学院学报(社会科学版)》 2000年第S1期144-149,共6页
This dissertaion will focus on the words English borrowed from Chinese to discuss the influence of Chinese culture on English. In the history of word borrowing, it is not until in the 18 th and 19th century that there... This dissertaion will focus on the words English borrowed from Chinese to discuss the influence of Chinese culture on English. In the history of word borrowing, it is not until in the 18 th and 19th century that there was a flood of Chinese loanwords into English. Most of the words are nouns about custom,culture, and goods with Chinese characteristic. The Chinese loanwords set foot into English by the means of transliteration, Among all Chinese dialects Mandarin, Cantonese and Amoy contributed most to English. Other languages such as Japanese bridged the borrowing process,too. 展开更多
关键词 ENGLISH borrowing CHINESE LOANWORDS BACKGROUND feature means
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Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital 被引量:2
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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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Resource management with borrowing from reservation for cognitive networks
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作者 李丹丹 Zhang Runtong +1 位作者 Shang Xiaopu Chen Ying 《High Technology Letters》 EI CAS 2013年第3期301-308,共8页
Resource reservation is an effective measure to ensure end-to-end quality of service (QoS), however, the burstyness of the traffic makes the reservation idle some time, and forms a waste of re- sources. Based on the... Resource reservation is an effective measure to ensure end-to-end quality of service (QoS), however, the burstyness of the traffic makes the reservation idle some time, and forms a waste of re- sources. Based on the analysis of active queue management (AQM) of DiffServ network, we propose a resource management scheme, which allows borrowing resources from unused reservation, accord- ing to the characteristics and advantages of cognitive networks. First, some nodes reserve certain proportion capacity for some special services (for instance, some services pay additional money) to guarantee the priority of these applications. Then resources are assigned according to the different parameters of services. If the available resource can not meet the requirements of new services, real- time ones are admitted with higher priority and allow borrowing the unused reservation from other nodes appropriately. Simulations show that, the proposed scheme has good performance at network resource utilization, the admission rate of new aDolications and OoS of users. 展开更多
关键词 cognitive networks resource reservation adaptive borrowing quality of service( Qos
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A novel spectrum borrowing scheme in integrated 3G/WLAN networks
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作者 李希金 Ji Hong Zhang Lin 《High Technology Letters》 EI CAS 2012年第2期155-159,共5页
In the heterogeneous wireless networks of the next generation, a large number of different radio access technologies will be integrated into a common network. This paper considers optimizing the utilization of spectru... In the heterogeneous wireless networks of the next generation, a large number of different radio access technologies will be integrated into a common network. This paper considers optimizing the utilization of spectrum resource in heterogeneous environment consisting two different networks: wireless local area network (WLAN) and time division-synchronous code division multiple access (TD-SCDMA) network. An optimal joint spectrum borrowing scheme maximizing overall network revenue is proposed with quality of service (QoS) constraints over both the WLAN and the TD-SCDMA cellular networks. Simulation results illustrate that system revenue earned in the proposed joint spectrum borrowing scheme is significantly larger than the case when individual networks are optimized independently. 展开更多
关键词 heterogeneous wireless network integrated network spectrum borrowing
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Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts 被引量:1
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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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An Analysis of Lexical Borrowing From Languages: "Konglish"
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作者 CUI Xue-bo 《Sino-US English Teaching》 2012年第2期952-957,共6页
This paper analyzes English loan words in Korean language. English words and phrases are largely absorbed into Korean either out of filling lexical gap or at the whim of fashion. These words have been borrowed and ada... This paper analyzes English loan words in Korean language. English words and phrases are largely absorbed into Korean either out of filling lexical gap or at the whim of fashion. These words have been borrowed and adapted orthographically and become a part of Korean language. Some loan words have the same meaning or phonological features as their corresponding words, but some do not. The only real solution to the "false friends" is to be aware of them, to look out for them, and to learn them. Teachers of English need to raise learners' awareness of the existence of English-origin words in fheir mother tongues 展开更多
关键词 lexical borrowing "Konglish" loan words "false friends"
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The Public Savings’ Relation With Borrowing Requirement and Financial Balances After Global Crisis in Turkey
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作者 Niyazi OZKER 《Economics World》 2017年第5期435-443,共9页
In this study, we aim to determine public savings’ structural location in the analysis of effect levels that are related to public borrowing requirement to cope with the deviation of financial balances, especially af... In this study, we aim to determine public savings’ structural location in the analysis of effect levels that are related to public borrowing requirement to cope with the deviation of financial balances, especially after 2009 global crisis in Turkey. Public savings as a financial option take up an important place in the scope of expressed government budget balances related to public borrowing requirements which are increasingly located together with budget deficits. This fact especially is pertaining to investments and capital’s transfers that are subject to the public decision making process towards economic growth in the future in developing countries like Turkey. Therefore, increasing public savings’ limits appear on these countries as an inevitable financial phenomenon concerning the desired investments. Turkey, as a developing country, has faced two financial phenomenons that increase borrowing requirement terms that lead to intend financial balances that have generally deviated after 2009 financial crisis. Firstly, it’s increasing foreign debt burden and the public savings’ levels that have not been enough to cover all the proportion of foreign debt payments since 2009. Secondly, the effect level of global crisis on the exchange rates directly causes the deviation of national currency values as a meaningful important negative impact on budget balances that are aimed at together with the macroeconomic financial balances. 展开更多
关键词 financial crisis foreign debt burden national investments public borrowing requirement public savings
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Long-term outcomes after endoscopic removal of malignant colorectal polyps:Results from a 10-year cohort 被引量:1
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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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Source Text Borrowing in Summary of Integrated Writing
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作者 XIE Xin-ran 《Journal of Literature and Art Studies》 2023年第9期699-703,共5页
Integrated writing tasks,requiring writers to summarize source content and integrate their ideas or experience with those in the source text,are widely used in standardized tests of English proficiency.Integrated writ... Integrated writing tasks,requiring writers to summarize source content and integrate their ideas or experience with those in the source text,are widely used in standardized tests of English proficiency.Integrated writing adds an element not found in traditional independent writing:the use of source text material.Recently,concern has been raised that over-reliance on source texts in integrated writing may lead to plagiarism as well as inaccurate assessment which calls for further investigation.Research on L2 students’writing using sources has broadened its focus from transgressive citing practices to stages of skill development in this complicated literacy,the successive challenges students face,and how instruction might be of benefit.Previous literature mainly focused on source use in academic writing and seldom considered summary writing in standardized tests,while summary strategy is particularly important in standardized tests,in which summary accounts for a significant part of the assessment criteria.Given that a series of previous literature have indicated that source text use,source texts,and prompts are associated with the quality of summary writing,this article reviews the source text borrowing in the summary of integrated writing to further explore the relationship between some variables and the quality of summary writing and therefore finds some research gaps in this field. 展开更多
关键词 summary writing source text borrowing integrated writing PARAPHRASING
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A Study of Borrowing,Imitation and Creation in English-Chinese Translation:A Case Study of Translating“The Root Cause of Poverty”
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作者 FAN Lian-yi ZHANG Shun-sheng 《Journal of Literature and Art Studies》 2022年第9期939-943,共5页
Based on the translated version of“The Root Cause of Poverty”by Rutger Bregman on the Ted speech online platform,this research analyzes the application of direct borrowing,imitative translation and creative translat... Based on the translated version of“The Root Cause of Poverty”by Rutger Bregman on the Ted speech online platform,this research analyzes the application of direct borrowing,imitative translation and creative translation in English-Chinese translation.First,we believe the direct borrowing of a ready-made version is most ideal as it reveals the common ground both languages share when translating a source text.Next,it is preferable to imitate an already existing expression as similarity is reader-friendly.However,it is sometimes necessary to adopt creative translation to preserve differences to ensure that the meaning of the original language is accurately transmitted. 展开更多
关键词 The Root Cause of Poverty direct borrowing imitative translation creative translation
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Discussion on E-books and Library Borrowing Service
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作者 Weiguo Xie 《Journal of Electronic Research and Application》 2021年第4期4-7,共4页
With the vigorous development of network information technology,e-book borrowing service came into being and showed a vigorous development trend.Therefore,in order to strengthen the service function,the library needs ... With the vigorous development of network information technology,e-book borrowing service came into being and showed a vigorous development trend.Therefore,in order to strengthen the service function,the library needs to gradually improve the e-book borrowing service,so as to provide readers with high-quality service content,so that the library can give full play to its function of disseminating scientific and cultural knowledge.Therefore,in this article research,we first discuss the main reading methods of e-books,then investigate the current reading situation of e-books and traditional paper books in the library,and then put forward corresponding development strategies to effectively promote the rapid development of the library and strengthen the level of e-book borrowing service. 展开更多
关键词 E-BOOKS LIBRARY borrowing service
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“Em”:Pragmatics Borrowing in Chinese Wechat Conversations:among Female University Students in China
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作者 王羽佩 《海外英语》 2020年第15期264-266,共3页
The term“pragmatics borrowing”refers to a conscious use of foreign pragmatic marker within or between utterances.Distinctive pragmatics functions of using the“cross-linguistic”pragmatic markers in online conversat... The term“pragmatics borrowing”refers to a conscious use of foreign pragmatic marker within or between utterances.Distinctive pragmatics functions of using the“cross-linguistic”pragmatic markers in online conversations have become a research focus.In a sample of Wechat communication among university students,the English pragmatics marker“em”and its variations occurred frequently.By analyzing its spelling variations,placement,pragmatic meanings and functions,the study indicates that,besides using it as a hesitator,chat participants consciously use this foreign pragmatic marker as a buffer for later utterance,which is usually an apology or a request,to soften the intonation and give the addressee an impression of politeness. 展开更多
关键词 pragmatic marker pragmatic borrowing Wechat conversation conversation analysis
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Tailoring Iron-Ion Release of Cellulose-Based Aerogel-Coated Iron Foam for Long-Term High-Power Microbial Fuel Cells
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作者 Zhengyang Ni Huitao Yu +6 位作者 Haoran Wang Mengmeng Qin Feng Li Hao Song Xiangyu Chen Yiyu Feng Wei Feng 《Transactions of Tianjin University》 EI CAS 2024年第5期436-447,共12页
The presence of iron(Fe) has been found to favor power generation in microbial fuel cells(MFCs). To achieve long-term power production in MFCs, it is crucial to effectively tailor the release of Fe ions over extended ... The presence of iron(Fe) has been found to favor power generation in microbial fuel cells(MFCs). To achieve long-term power production in MFCs, it is crucial to effectively tailor the release of Fe ions over extended operating periods. In this study, we developed a composite anode(A/IF) by coating iron foam with cellulose-based aerogel. The concentration of Fe ions in the anode solution of A/IF anode reaches 0.280 μg/mL(Fe^(2+) vs. Fe^(3+) = 61%:39%) after 720 h of aseptic primary cell operation. This value was significantly higher than that(0.198 μg/mL, Fe^(2+) vs. Fe^(3+) = 92%:8%) on uncoated iron foam(IF), indicating a continuous release of Fe ions over long-term operation. Notably, the resulting MFCs hybrid cell exhibited a 23% reduction in Fe ion concentration(compared to a 47% reduction for the IF anode) during the sixth testing cycle(600-720 h). It achieved a high-power density of 301 ± 55 mW/m^(2) at 720 h, which was 2.62 times higher than that of the IF anode during the same period. Furthermore, a sedimentary microbial fuel cell(SMFCs) was constructed in a marine environment, and the A/IF anode demonstrated a power density of 103 ± 3 mW/m^(2) at 3240 h, representing a 75% improvement over the IF anode. These findings elucidate the significant enhancement in long-term power production performance of MFCs achieved through effective tailoring of Fe ions release during operation. 展开更多
关键词 Microbial fuel cells Coating Fe ions Tailor release long-term
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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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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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