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Non-simultaneous Blow-up Criteria for Localized Parabolic Equations 被引量:1
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作者 LI FENG-JIE LIu BING-CHEN ZHENG SI-NING 《Communications in Mathematical Research》 CSCD 2009年第4期379-384,共6页
This paper deals with blow-up solutions for parabolic equations coupled via localized exponential sources, subject to homogeneous Dirichlet boundary con- ditions. The criteria are proposed to identify simultaneous and... This paper deals with blow-up solutions for parabolic equations coupled via localized exponential sources, subject to homogeneous Dirichlet boundary con- ditions. The criteria are proposed to identify simultaneous and non-simultaneous blow-up solutions. The related classification for the four nonlinear parameters in the model is optimal and complete. 展开更多
关键词 non-simultaneous blow-up simultaneous blow-up critical exponent
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THE SIMULTANEOUS AND NON-SIMULTANEOUS BLOW-UP CRITERIA FOR A DIFFUSION SYSTEM
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作者 凌征球 王泽佳 张国强 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期139-149,共11页
This paper investigates the finite time blow-up of nonnegative solutions for a nonlinear diffusion system with a more complicated source term, which is a product of localized source, local source, and weight function,... This paper investigates the finite time blow-up of nonnegative solutions for a nonlinear diffusion system with a more complicated source term, which is a product of localized source, local source, and weight function, and complemented by homogeneous Dirichlet boundary conditions. The criteria are proposed to identify simultaneous and nonsimultaneous blow-up solutions. Moreover, the related classification for the four parameters in the model is optimal and complete. The results extend those in Zhang and Yang [12]. 展开更多
关键词 blow-up simultaneous and non-simultaneous blow-up critical exponent dif-fusion system
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Multi-Model Approach for Assessing the Influence of Calibration Criteria on the Water Balance in Ouémé Basin
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作者 Aymar Yaovi Bossa Mahutin Aristide Oluwatobi Kpossou +1 位作者 Jean Hounkpè Félicien Djigbo Badou 《Journal of Water Resource and Protection》 CAS 2024年第3期207-218,共12页
Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteri... Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling. 展开更多
关键词 Hydrological Modelling Performance criteria Water Balance Ouémé Basin
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Unequal Distribution of Innovation Efforts for Neglected Tropical Diseases: The Role of Funding Evaluation Criteria
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作者 Anne M. G. Neevel Kenneth D. S. Fernald Linda H. M. van de Burgwal 《Health》 2024年第5期490-520,共31页
Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease.... Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease. However, within the field of neglected tropical diseases some seem far more neglected than others. In this research the aim is to investigate the distribution of resources and efforts, as well as the mechanisms that underpin funding allocation for neglected tropical diseases. Methodology: A systematic literature review was conducted to establish a comprehensive overview of known indicators for innovation efforts related to a wide range of neglected tropical diseases. Articles were selected based on a subjective evaluation of their relevance, the presence of original data, and the breadth of their scope. This was followed by thirteen in-depth open-ended interviews with representatives of private, public and philanthropic funding organizations, concerning evaluation criteria for funding research proposals. Results: The findings reveal a large difference in the extent to which the individual diseases are neglected with notable differences between absolute and relative efforts. Criteria used in the evaluation of research proposals relate to potential impact, the probability of success and strategic fit. Private organizations prioritize strategic fit and economic impact;philanthropic organizations prioritize short-term societal impact;and public generally prioritize the probability of success by accounting for follow-up funding and involvement of industry. Funding decisions of different types of organizations are highly interrelated. Conclusions: This study shows that the evaluation of funding proposals introduces and retains unequal funding distribution, reinforcing the relative neglect of diseases. Societal impact is the primary rationale for funding but application of it as a funding criterion is associated with significant challenges. Furthermore, current application of evaluation criteria leads to a primary focus on short-term impact. Through current practice, the relatively most neglected diseases will remain so, and a long-term strategy is needed to resolve this. 展开更多
关键词 Neglected Tropical Diseases Funding Decision Evaluation criteria Health Research Funding Research Impact
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Local Criteria Used by Farmers to Evaluate the Agronomic Performance and the Fertilizing Capacity of Cowpea Varieties: Diversity, Variability and Proximal Relation with Agronomic Measurements in Contrasted Sahelian Locations
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作者 Nouhou Salifou Jangorzo Abdoul-Aziz Saïdou +2 位作者 Abou-Soufianou Sadda Abdoulaye Moussa Mamoudou Hassane Bil-Assanou Issoufou 《Agricultural Sciences》 2024年第1期114-131,共18页
When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific... When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations. 展开更多
关键词 Agronomic Performance Participatory Research COWPEA Farmers’ criteria
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BLOW-UP CONDITIONS FOR A SEMILINEAR PARABOLIC SYSTEM ON LOCALLY FINITE GRAPHS
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作者 吴艺婷 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期609-631,共23页
In this paper, we investigate a blow-up phenomenon for a semilinear parabolic system on locally finite graphs. Under some appropriate assumptions on the curvature condition CDE’(n,0), the polynomial volume growth of ... In this paper, we investigate a blow-up phenomenon for a semilinear parabolic system on locally finite graphs. Under some appropriate assumptions on the curvature condition CDE’(n,0), the polynomial volume growth of degree m, the initial values, and the exponents in absorption terms, we prove that every non-negative solution of the semilinear parabolic system blows up in a finite time. Our current work extends the results achieved by Lin and Wu (Calc Var Partial Differ Equ, 2017, 56: Art 102) and Wu (Rev R Acad Cien Serie A Mat, 2021, 115: Art 133). 展开更多
关键词 semilinear parabolic system on graphs blow-up heat kernel estimate on graphs
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Evaluation of AVNRT & AVRT by Different Criteria: Old & New
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作者 Abdul Hamid Tahmina Alam Sonali +3 位作者 Rizwan Rehan Pijous Biswas Subas Caandro Datta Asif Zaman 《World Journal of Cardiovascular Surgery》 2024年第7期95-106,共12页
The two most frequent causes of paroxysmal SVT are atrioventricular tachycardia (AVRT) and atrioventricular nodal re-entrant tachycardia (AVNRT). The purpose of this study was to assess the diagnostic efficacy of trad... The two most frequent causes of paroxysmal SVT are atrioventricular tachycardia (AVRT) and atrioventricular nodal re-entrant tachycardia (AVNRT). The purpose of this study was to assess the diagnostic efficacy of traditional and newly proposed ECG criteria in the identification of Avnrt and Avrt. Aim of the Study: The aim of this study was to evaluate Atrioventricular Nodal Reentrant Tachycardia (AVNRT) and Atrioventricular Re-entrant Tachycardia (AVRT) using both traditional and novel criteria. Methods: This prospective observational study was conducted at the Electrophysiology Unit, Department of Cardiology, National Institute of Cardiovascular Diseases (NICVD) in Dhaka, from February 2019 to January 2020. A total of 62 patients with Supraventricular Tachycardia (SVT) undergoing electrophysiology study (EPS) were included. Standard ECG criteria were applied for the differential diagnosis, and electrophysiological diagnoses were made using established criteria. Statistical analysis, including descriptive statistics and appropriate tests, was performed using SPSS 23.0. Result: In our study of 62 patients with Supraventricular Tachycardia (SVT), we found that 66.1% had AVNRT and 33.9% had AVRT. The mean age in AVNRT was higher than AVRT (41.3 ± 9.7 vs. 38.5 ± 14.3, p = 0.36) with statistically no significant difference, with similar gender distribution between AVNRT and AVRT groups. Classical AVNRT criteria were present in 30.6% of patients, and 45.2% showed a Pseudo R' wave in aVR. Additionally, 30.6% had an RP interval ≥100ms, more prevalent in AVRT patients (66.7%). Conclusion: Integrating traditional and novel criteria, including lead aVR analysis, enhances the electrocardiographic diagnosis of AVNRT and AVRT, offering a pathway to refined patient care. 展开更多
关键词 SVT (Supraventricular Tachycardia) AVNRT (Atrioventricular Nodal Re-Entrant Tachycardia) AVRT (Atrioventricular Re-Entrant Tachycardia) ECG criteria Electrophysiology
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基于Beers Criteria 2023 评估我院门诊老年患者潜在不适当用药现状
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作者 陈遥 蒋军 《海峡药学》 2024年第7期82-85,共4页
目的评估我院门诊老年患者潜在不适当用药(PIM)的发生情况,分析影响因素,探讨如何促进老年合理用药。方法收集常州市第一人民医院2023年5月~2023年7月,年龄65~99岁门诊患者处方,按照Beers Criteria 2023对患者的用药进行分析,采用二元lo... 目的评估我院门诊老年患者潜在不适当用药(PIM)的发生情况,分析影响因素,探讨如何促进老年合理用药。方法收集常州市第一人民医院2023年5月~2023年7月,年龄65~99岁门诊患者处方,按照Beers Criteria 2023对患者的用药进行分析,采用二元logistic回归模型分析发生PIM的影响因素。结果最终筛选出24217例患者,男11823例,占比48.8%,女12394例,占比51.2%。疾病数量、用药种类、年龄为PIM发生的危险因素,就诊科室数为保护因素(P<0.05)。结论Beers Criteria 2023检出PIM率为20.37%,临床药师应结合临床,减少用药种类以减少老年患者PIM的发生率,对必需使用导致PIM药物治疗的老年患者应加强监测并个体化用药,保证老年患者用药安全。 展开更多
关键词 门诊 合理用药 潜在不适当用药 老年人 Beers标准
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GIS-Based Multi-Criteria Decision Analysis (MCDA) and Analytical Hierarchy Process (AHP) Techniques to Derive Flood Risks Management on Rice Productivity in Gishari Marshland
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作者 Jean Nepo Nsengiyumva Emmanuel Nshimiyimana +7 位作者 Jean Marie Ntakirutimana Phocas Musabyimana Yvonne Akimana Fred Shema Set Niyitanga Séverin Hishamunda Callixte Musinga Mpamabara Eliezel Habineza 《Journal of Geoscience and Environment Protection》 2024年第3期222-249,共28页
Floods are phenomenon with significant socio-economic implications mainly for human loss, agriculture, livestock, soil loss and land degradation, for which many researchers try to identify the most appropriate methodo... Floods are phenomenon with significant socio-economic implications mainly for human loss, agriculture, livestock, soil loss and land degradation, for which many researchers try to identify the most appropriate methodologies by analyzing their temporal and spatial development. This study therefore attempts to employ the GIS-based multi-criteria decision analysis and analytical hierarchy process techniques to derive the flood risks management on rice productivity in the Gishari Agricultural Marshland in Rwamagana district, Rwanda. Here, six influencing potential factors to flooding, including river slope, soil texture, Land Use Land Cover through Land Sat 8, rainfall, river distance and Digital Elevation Model are considered for the delineation of flood risk zones. Data acquisition like Landsat 8 images, DEM, land use land cover, slope, and soil class in the study area were considered. Results showed that if the DEM is outdated or inaccurate due to changes in the terrain, such as construction, excavation, or erosion, the predicted flood patterns might not reflect the actual water flow. This could result unexpected flood extents and depths, potentially inundating rice fields that were not previously at risk and this, expectedly explained that the increase 1 m in elevation would reduce the rice productivity by 0.17% due to unplanned flood risks in marshland. It was found that the change in rainfall distribution in Gishari agricultural marshland would also decrease the rice productivity by 0.0018%, which is a sign that rainfall is a major factor of flooding in rice scheme. Rainfall distribution plays a crucial role in flooding analysis and can directly impact rice productivity. Oppositely, another causal factor was Land Use Land Cover (LULC), where the Multivariate Logistic Regression Model Analysis findings showed that the increase of one unit in Land Use Land Cover would increase rice productivity by 0.17% of the total rice productivity from the Gishari Agricultural Marshland. Based on findings from these techniques, the Gishari Agricultural Marshlands having steeped land with grassland is classified into five classes of flooding namely very low, low, moderate, high, and very high which include 430%, 361%, 292%, 223%, and 154%. Government of Rwanda and other implementing agencies and major key actors have to contribute on soil and water conservation strategies to reduce the runoff and soil erosion as major contributors of flooding. 展开更多
关键词 Multi criteria Decision Analysis (MCDA) Analytical Hierarchy Analysis (AHA) GIS RS and DEM
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Contribution of GIS to Soil Landscape Mapping by Multi-Criteria Analysis Using Weighting: The Case of the Square Degrees of M’Bahiakro (Centre) and Daloa (Centre-West) in Ivory Coast
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作者 Guy Fernand Yao Derving Baka +5 位作者 Nestor Kouman Yao Kouakou Bala Mamadou Ouattara Kouadio Amani Jean Lopez Essehi Brou Kouame Albert Yao-Kouame 《Open Journal of Geology》 CAS 2024年第1期101-116,共16页
As part of the drive to improve coffee and cocoa production in Ivory Coast, studies are carried out to identify soils that are favourable for these crops. It is therefore necessary to orientate soil investigations bas... As part of the drive to improve coffee and cocoa production in Ivory Coast, studies are carried out to identify soils that are favourable for these crops. It is therefore necessary to orientate soil investigations based on reliable criteria that best discriminate soil cover. With this in mind, this study is being carried out to help improve survey methods by mapping soil landscapes. It uses GIS and weighted multicriteria analysis. To do this, satellite images were processed and the geological map of the square degrees of M’Bahiakro and Daloa was reclassified. The results show that relief is the main factor in soil landscape differentiation, with respective weights of 0.58 and 0.67 for the forest and pre-forest zones. In contrast, the weight of geological formation in soil landscape differentiation remains low (0.05 for the forest zone and 0.07 for the pre-forest zone). The criteria used on the base of aggregation sum methods have made it possible to formulate soil landscape mapping prediction functions according to agro-ecological environments in the humid intertropical zone. This is essential for the orientation of soil survey work. Nevertheless, other comparative methods, such as the coding mapping method, could provide elements for discussion to validate the models. 展开更多
关键词 GIS Multi-criteria Analysis Soil Landscapes M’Bahiakro Daloa Ivory Coast
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Multi-Criteria Wildfire Risk Hazard Assessment in GIS Environment: Projection for the Future and Impact on RES Projects Installation Planning
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作者 Aggelos Pallikarakis Flora Konstantopoulou 《Journal of Geoscience and Environment Protection》 2024年第5期242-265,共24页
It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is M... It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is Mediterranean, due to the unique combination of its type of vegetation and demanding climatic conditions. This research is focused on the Region of Epirus in Greece, an area with significant natural vegetation and a range of geomorphological aspects. In order to estimate the Wildfire Risk Hazard, several factors have been used: geomorphological (slope, aspect, elevation, TWI, Hydrographic network), social (Settlements and landfils, roads, overhead lines and substations), environmental (land cover) and climatic (Fire Weather Index). Through a multi-criteria decision analysis (MCDA) and an analytic hierarchy process (AHP) in a GIS environment, the Wildfire Risk Hazard has been estimated not only for current conditions but also for future projections for the near future (2031-2060) and the far future (2071-2100). The selected case study includes the potential impact of the Wildfires to the installed (or targeted to be installed) RES projects in the studied region. 展开更多
关键词 RES Projects Greece Epirus Analytic Hierarchy Process Multi-criteria Decision Analysis
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Blow-up criteria and periodic peakons for a two-component extension of the μ-version modified Camassa-Holm equation
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作者 李志刚 赵忠龙 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第3期21-28,共8页
Some two-component extensions of the modifiedμ-Camassa-Holm equation are proposed.We show that these systems admit Lax pairs and bi-Hamiltonian structures.Furthermore,we consider the blow-up phenomena for one of thes... Some two-component extensions of the modifiedμ-Camassa-Holm equation are proposed.We show that these systems admit Lax pairs and bi-Hamiltonian structures.Furthermore,we consider the blow-up phenomena for one of these extensions(2μmCH),and the periodic peakons of this system are derived. 展开更多
关键词 modifiedμ-Camassa-Holm equation bi-Hamiltonian structures blow-up peakons
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Application of extended criteria donor grafts in liver transplantation for acute-on-chronic liver failure:A retrospective cohort study 被引量:1
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作者 Jin-Long Gong Jia Yu +3 位作者 Tie-Long Wang Xiao-Shun He Yun-Hua Tang Xiao-Feng Zhu 《World Journal of Gastroenterology》 SCIE CAS 2023年第41期5630-5640,共11页
BACKGROUND There is no consensus on the usage of extended criteria donor(ECD)grafts in liver transplantation(LT)for acute-on-chronic liver failure(ACLF)patients.AIM To summarize the experience of using ECD livers in A... BACKGROUND There is no consensus on the usage of extended criteria donor(ECD)grafts in liver transplantation(LT)for acute-on-chronic liver failure(ACLF)patients.AIM To summarize the experience of using ECD livers in ACLF-LT.METHODS A retrospective cohort study was conducted,enrolling patients who underwent LT at the First Affiliated Hospital of Sun Yat-Sen University from January 2015 to November 2021.The patients were divided into ECD and non-ECD groups for analysis.RESULTS A total of 145 recipients were enrolled in this study,of which ECD and non-ECD recipients accounted for 53.8%and 46.2%,respectively.Donation after cardiac death(DCD)recipients accounted for the minority compared with donation after brain death(DBD)recipients(16.6%vs 83.4%).Neither overall survival nor graft survival significantly differed between ECD and non-ECD and DCD and DBD recipients.ECD grafts were associated with a significantly higher incidence of early allograft dysfunction(EAD)than non-ECD grafts(67.9%vs 41.8%,P=0.002).Postoperative outcomes between DCD and DBD recipients were comparable(P>0.05).ECD graft(P=0.009),anhepatic phase(P=0.034)and recipient gamma glutamyltransferase(P=0.016)were independent risk factors for EAD.Recipient preoperative number of extrahepatic organ failures>2(P=0.015)and intraoperative blood loss(P=0.000)were independent predictors of poor post-LT survival.CONCLUSION Although related to a higher risk of EAD,ECD grafts can be safely used in ACLF-LT.The main factors affecting post-LT survival in ACLF patients are their own severe preoperative disease and intraoperative blood loss. 展开更多
关键词 Extended criteria donor Acute-on-chronic liver failure Liver transplantation
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Extended criteria brain-dead organ donors:Prevalence and impact on the utilisation of livers for transplantation in Brazil 被引量:1
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作者 Victoria S Braga Amanda P C S Boteon +2 位作者 Heloisa B Paglione Rafael A A Pecora Yuri L Boteon 《World Journal of Hepatology》 2023年第2期255-264,共10页
BACKGROUND Despite its association with higher postoperative morbidity and mortality,the use of extended criteria donor(ECD)livers for transplantation has increased globally due to the high demand for the procedure.AI... BACKGROUND Despite its association with higher postoperative morbidity and mortality,the use of extended criteria donor(ECD)livers for transplantation has increased globally due to the high demand for the procedure.AIM To investigate the prevalence of ECD in donation after brain death(DBD)and its impact on organ acceptance for transplantation.METHODS Retrospective analysis of DBD organ offers for liver transplantation between 2017 and 2020 in a high-volume transplant centre.The incidence of the Eurotransplant risk factors to define an ECD(ET-ECD)among DBD donors and the likelihood of organ acceptance over the years were analysed.The relationship between organ refusal for transplantation,the occurrence,and the number of ET-ECD was assessed by simple and multiple logistic regression adjustment.RESULTS A total of 1619 organ donors were evaluated.Of these,78.31%(n=1268)had at least one ET-ECD criterion.There was an increase in the acceptance of ECD DBD organs for transplantation(1 criterion:from 23.40%to 31.60%;2 criteria:from 13.10%to 27.70%;3 criteria:From 6.30%to 13.60%).For each addition of one ETECD variable,the estimated chance of organ refusal was 64.4%higher(OR 1.644,95%CI 1.469-1.839,P<0.001).Except for the donor serum sodium>165 mmol/L(P=0.310),all ET-ECD criteria increased the estimated chance of organ refusal for transplantation.CONCLUSION A high prevalence of ECD DBD was observed.Despite the increase in their utilisation,the presence and the number of extended donor criteria were associated with an increased likelihood of their refusal for transplantation. 展开更多
关键词 Liver transplantation Extended criteria donors Donation after brain death Organ donation
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Deformation characteristics and novel strain criteria of strainbursts induced by low-frequency cyclic disturbance 被引量:2
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作者 Lihua Hu Minghe Ju +1 位作者 Peng Zhao Xiaozhao Li 《Deep Underground Science and Engineering》 2023年第1期52-60,共9页
Strainbursts induced by cyclic disturbance with low frequency(termed as cyclicinduced strainbursts)are major dynamic disasters during deep excavation and mining.There is currently no quantitative criterion available f... Strainbursts induced by cyclic disturbance with low frequency(termed as cyclicinduced strainbursts)are major dynamic disasters during deep excavation and mining.There is currently no quantitative criterion available for the prediction of such disastrous events.In this study,based on true triaxial experiments,we analyzed the deformation characteristics,established two novel strain criteria for the cyclic-induced strainbursts,and explained the physical meaning of these criteria.Characteristic strains for the cyclic-induced strainbursts were defined,including the control strain ε_(ctr),the strain caused by the combined dynamic and static loading ε_(sd),and the ultimate strain ε_(u) after strainbursts.As indicated by the results,the deformation evolution of the cyclic-induced strainbursts shows remarkable fatigue characteristics,which resemble that of rock subjected to cyclic loading and unloading.In other words,there are three stages during deformation evolution,namely,initial rapid growth,uniform velocity growth after several periods of disturbance,and sudden sharp growth preceding the burst.The ultimate strain ε_(u) is insensitive to the tangential static stress and disturbance amplitude,but it changes nonlinearly with disturbance frequency.From the perspective of deformation,the occurrence of a cyclic-induced strainburst is controlled by the control strainε_(ctr).Thus,a control strain criterion is proposed;that is,when the stain ε_(sd) is larger than the control strain ε_(ctr),a strainburst will be induced by cyclic disturbance.Moreover,based on the statistical results,a strain ratio criterion is proposed;that is,when the strain ratio ε_(sd)/ε_(u) is greater than 30%,a cyclic-induced strainburst will be induced. 展开更多
关键词 dynamic disturbance low frequency strainbursts strain criteria true triaxial
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Derivation and validation of soil total and extractable cadmium criteria for safe vegetable production
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作者 LI Li-jun LI Kun +2 位作者 JIANG Bao LI Ju-mei MA Yi-bing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3792-3803,共12页
Determining the appropriate soil cadmium(Cd)criteria for vegetable production is important for ensuring that the Cd concentrations of the vegetables meet food safety standards.The soil extractable Cd criteria for vege... Determining the appropriate soil cadmium(Cd)criteria for vegetable production is important for ensuring that the Cd concentrations of the vegetables meet food safety standards.The soil extractable Cd criteria for vegetable production are also essential for both food safety and environmental management,especially in areas with a high natural background level.In the present study,soil total and extractable Cd criteria were derived using the approach of species sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties.A dataset of 90 vegetable species planted in different soils was compiled by screening the published in literature in five bibliographic databases using designated search strings.The empirical soil-plant transfer model was applied to normalize the bioaccumulation data.After normalization,the intra-species variability was reduced by 18.3 to 84.4%.The soil Cd concentration that would protect 95%(HC_(5))of the species was estimated by species sensitivity distribution curves that were fitted by the Burr III function.The soil Cd criteria derived from the added approach for risk assessment were proposed as continuous criteria based on a combination of organic carbon and pH in the soil.Criteria for total Cd and EDTA-extractable Cd in the soil ranged from 0.23 to 0.61 mg kg^(-1)and from 0.09 to 0.25 mg kg^(-1),respectively.Field experimental data were used to validate the applicability and validity of these criteria.Most of the predicted HC5 values in the field experimental sites were below the 1:1 line.These results provide a scientific basis for soil Cd criteria for vegetable production that will ensure food safety. 展开更多
关键词 CD VEGETABLES soil criteria species sensitivity distribution soil extractable Cd criteria
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BLOW-UP SOLUTIONS OF TWO-COUPLED NONLINEAR SCHR?DINGER EQUATIONS IN THE RADIAL CASE
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作者 白欠欠 李晓光 张莉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1852-1864,共13页
We consider the blow-up solutions to the following coupled nonlinear Schr¨odinger equations{iu_(t)+Δu+(|u|^(2p)+|u|^(p−1)|v|^(p+1))u=0,iv_(t)+Δv+(|v|^(2p)+|v|^(p−1)|u|^(p+1))v=0,u(0,x)=u0(x),v(0,x)=v0(x),x 2 R ... We consider the blow-up solutions to the following coupled nonlinear Schr¨odinger equations{iu_(t)+Δu+(|u|^(2p)+|u|^(p−1)|v|^(p+1))u=0,iv_(t)+Δv+(|v|^(2p)+|v|^(p−1)|u|^(p+1))v=0,u(0,x)=u0(x),v(0,x)=v0(x),x 2 R N,t0.On the basis of the conservation of mass and energy,we establish two sufficient conditions to obtain the existence of a blow-up for radially symmetric solutions.These results improve the blow-up result of Li and Wu[10]by dropping the hypothesis of finite variance((|x|u_(0),|x|v_(0))∈ L^(2)(R^(N))×L^(2)(R^(N))). 展开更多
关键词 SchrOdinger equations radial symmetry blow-up virial identity
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THE REGULARITY CRITERIA OF WEAK SOLUTIONS TO 3D AXISYMMETRIC INCOMPRESSIBLE BOUSSINESQ EQUATIONS
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作者 董玉 黄耀芳 +1 位作者 李莉 卢青 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2387-2397,共11页
In this paper,we obtain new regularity criteria for the weak solutions to the three dimensional axisymmetric incompressible Boussinesq equations.To be more precise,under some conditions on the swirling component of vo... In this paper,we obtain new regularity criteria for the weak solutions to the three dimensional axisymmetric incompressible Boussinesq equations.To be more precise,under some conditions on the swirling component of vorticity,we can conclude that the weak solutions are regular. 展开更多
关键词 Boussinesq equations regularity criteria AXISYMMETRY
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method)–Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm
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作者 Zoran Gligoric Milos Gligoric +2 位作者 Igor Miljanovic Suzana Lutovac Aleksandar Milutinovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期955-979,共25页
Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very impor... Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems.Three methods are commonly used for assessing the weights of criteria:objective,subjective,and integrated methods.In this study,an objective approach is proposed to assess the weights of criteria,called SPCmethod(Symmetry Point of Criterion).This point enriches the criterion so that it is balanced and easy to implement in the process of the evaluation of its influence on decision-making.The SPC methodology is systematically presented and supported by detailed calculations related to an artificial example.To validate the developed method,we used our numerical example and calculated the weights of criteria by CRITIC,Entropy,Standard Deviation and MEREC methods.Comparative analysis between these methods and the SPC method reveals that the developedmethod is a very reliable objective way to determine the weights of criteria.Additionally,in this study,we proposed the application of SPCmethod to evaluate the efficiency of themulti-criteria partitioning algorithm.The main idea of the evaluation is based on the following fact:the greater the uniformity of the weights of criteria,the higher the efficiency of the partitioning algorithm.The research demonstrates that the SPC method can be applied to solving different multi-criteria problems. 展开更多
关键词 Multi-criteria decision-making weights of criteria symmetry point of criterion mineral deposit partitioning algorithm performance evaluation
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