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THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING
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作者 赵敏 袁荣 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1096-1114,共19页
In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or ext... In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving frames.In particular,they achieved a complete picture in the local diffusion case.However,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s paper.By using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et al.to achieve a complete picture in the nonlocal diffusion case. 展开更多
关键词 predator-prey system persistence nonlocal dispersal shifting environment
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The Persistence and Zonal Scale of Atmospheric Dipolar Modes
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作者 Jie SONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期478-492,共15页
This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model sh... This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics. 展开更多
关键词 NAM NAO eddy feedback persistence linear term
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The Transport and Persistence of Escherichia coli in Leachate from Poultry Litter Amended Soils
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作者 Lorra Belle Hill 《Open Journal of Soil Science》 2024年第4期269-282,共14页
Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay s... Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay soil and Hartsells Sandy soil was conducted using soil columns and simulated groundwater leaching. Enumeration of initial E. coli was determined to range from 2.851 × 10<sup>3</sup> to 3.044 × 10<sup>3</sup> CFU per gram of soil. These results have been used in a batch study to determine the persistence rate of E. coli in Decatur silty Clay soil and Hartsells Sandy soil. Results prove that E. coli survival growth rate increases for clay soil later than and at a higher rate than sandy soil. The column study has determined that E. coli was transported at a rate of 3.7 × 10<sup>6</sup><sup> </sup>CFU for Decatur silty loam and 6.3 × 10<sup>6</sup><sup> </sup>CFU for Hartsells sandy per gram of soil. Further, linear regression analysis predictions show higher porosity and soil moisture content affect transport, and Hartsells sandy soil has higher transport of E. coli due to its higher porosity and lower volumetric water content. 展开更多
关键词 TRANSPORT LEACHATE persistence Poultry Litter E. coli
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Characteristics and Mechanisms of Persistent Wet–Cold Events with Different Cold-air Paths in South China
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作者 Xiaojuan SUN Li CHEN +1 位作者 Chuhan LU Panxing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1171-1183,共13页
We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part o... We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part of South China is higher than that in the eastern part.The pattern of single-station frequency of the PWCEs are“Yangtze River(YR)uniform”and“east–west inverse”.The YR uniform pattern is the dominant mode,so we focus on this pattern.The cold-air paths for PWCEs of the YR uniform pattern are divided into three types—namely,the west,northwest and north types—among which the west type accounts for the largest proportion.The differences in atmospheric circulation of the PWCEs under the three types of paths are obvious.The thermal inversion layer in the lower troposphere is favorable for precipitation during the PWCEs.The positive water vapor budget for the three types of PWCEs mainly appears at the southern boundary. 展开更多
关键词 persistent wet–cold events cold-air paths circulation characteristics water vapor
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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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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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Hydromassage of macular hole edges for large and persistent full-thickness macular holes
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作者 Yi Cai Wen-Bo Liu +5 位作者 Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期551-557,共7页
●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consec... ●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery. 展开更多
关键词 macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage
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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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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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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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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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A Trajectory Privacy Protection Method to Resist Long-Term Observation Attacks
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作者 Qixin Zhan 《Journal of Computer and Communications》 2024年第5期53-70,共18页
Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exp... Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exploited by opponents, greatly increasing the risk of trajectory privacy leakage. This attack method is called a long-term observation attack. On the premise of ensuring lower time overhead and higher cache contribution rate, the existing methods cannot utilize cache to answer subsequent queries while also resisting long-term observation attacks. So this article proposes a trajectory privacy protection method to resist long-term observation attacks. This method combines caching technology and improves the existing differential privacy mechanism, while incorporating randomization factors that are difficult for attackers to recognize after long-term observation to enhance privacy. Search for locations in the cache of both the mobile client and edge server that can replace the user’s actual location. If there are replacement users in the cache, the query results can be obtained more quickly. Simultaneously obfuscating the spatiotemporal correlation of actual trajectories by generating confusion regions. If it does not exist, the obfuscated location generation method that resists long-term observation attacks is executed to generate the real anonymous area and send it to the service provider. The above steps can comprehensively protect the user’s trajectory privacy. The experimental results show that this method can protect user trajectories from long-term observation attacks while ensuring low time overhead and a high cache contribution rate. 展开更多
关键词 Location Privacy long-term Observation Attacks K-ANONYMITY Location Caching
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Exploring the Long-Term Mechanism of the Construction of College Teachers’Ethics in the New Era Under the Concept of“Sanquan Education”
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作者 Jing Zuo Xiaoyue Liu 《Journal of Contemporary Educational Research》 2024年第1期140-146,共7页
This paper takes the long-term mechanism exploration of the construction of teachers’ethics in the new era under the concept of“Sanquan education,”aiming to explore how to establish a long-term mechanism of the con... This paper takes the long-term mechanism exploration of the construction of teachers’ethics in the new era under the concept of“Sanquan education,”aiming to explore how to establish a long-term mechanism of the construction to meet the needs of college education development under the background of the new era.A series of targeted measures and suggestions are put forward,including improving the system and mechanism,strengthening the education and training of teachers’ethics,and establishing the evaluation and assessment mechanism.The implementation of these measures can promote the formation of the long-term mechanism of the construction of teachers’ethics in colleges and universities,improve teachers’ethics and behavior quality,and provide strong support for the development of education in colleges and universities. 展开更多
关键词 Sanquan education ETHICS College education long-term mechanism Teacher quality
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Photoelectric State with Long-Term Relaxation in CdTe:(Ag, Cu, Cd) and Sb2Se3:Se Photovoltaic Films
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作者 Ozodbek Ravshanboy o‘g‘li Nurmatov Dilkhumor Tolibjonovna Mamadieva Nosirjon Khaydarovich Yuldashev 《Journal of Applied Mathematics and Physics》 2024年第1期43-51,共9页
The results of an experimental study of long-term relaxation of the photoelectret state of polycrystalline CdTe:(Ag, Cu, Cd) and Sb<sub>2</sub>Se<sub>3</sub>:Se films with an anomalous photovol... The results of an experimental study of long-term relaxation of the photoelectret state of polycrystalline CdTe:(Ag, Cu, Cd) and Sb<sub>2</sub>Se<sub>3</sub>:Se films with an anomalous photovoltaic property are presented. In such films, the residual photovoltage is caused by the separation of photocarriers by the built-in electrostatic field of the near-surface region of space charges and their asymmetric capture by deep levels of impurities or complexes, including impurity atoms and intrinsic defects, both in the bulk and on the surface of crystal grains. It has been shown that in activated films, a two-step exponential temporary relaxation of the initial photovoltage of the order of V<sub>APV</sub> ≈ (500-600) V is detected, and only 10% of it experiences long-term relaxation (t ≈ 100-120 min). 展开更多
关键词 Thin Polycrystalline Films Doping Deep Centers Anomalous Photovoltage Photoelectret State long-term Relaxation
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Persistence of hepatitis B vaccine immune protection and response to hepatitis B booster immunization 被引量:15
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作者 LI Hui 1, LI Rong Cheng 2, LIAO Su Su 1, YANG Jin Ye 2, ZENG Xian Jia 1 and WANG Shu Sheng 2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第6期38-41,共4页
AbstractAIMToidentifythepersistenceofimmuneprotectionofChinamade,plasmaderivedhepatitisBvaccineafterinfanc... AbstractAIMToidentifythepersistenceofimmuneprotectionofChinamade,plasmaderivedhepatitisBvaccineafterinfancyimmunizationandt... 展开更多
关键词 HEPATITIS B vaccines IMMUNE PROTECTION persistence BOOSTER IMMUNIZATION
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PERSISTENCE AND GLOBAL STABILITY FOR A THREE-SPECIES RATIO-DEPENDENT PREDATOR-PREY SYSTEM WITH TIME DELAYS IN TWO-PATCH ENVIRONMENTS 被引量:12
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作者 徐瑞 陈兰荪 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期533-541,共9页
A three-species ratio-dependent predator-prey diffusion model with time delays is investigated. It is shown that the system is uniformly persistent under some appropriate conditions, and sufficient conditions axe obta... A three-species ratio-dependent predator-prey diffusion model with time delays is investigated. It is shown that the system is uniformly persistent under some appropriate conditions, and sufficient conditions axe obtained for the global stability of the positive equilibrium of the system. 展开更多
关键词 time delay diffusion uniform persistence global asymptotic stability
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