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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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Design optimization and FEA of B-6 and B-7 levels ballistics armor:A modelling approach
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作者 Muhammad Naveed CHU Jinkui +1 位作者 Atif Ur Rehman Arsalan Hyder 《大连理工大学学报》 北大核心 2026年第1期66-77,共12页
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl... Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor. 展开更多
关键词 radiator armor ballistics simulation Johnson-Cook model armor-piercing projectile perforated D-shaped armor plate
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Do Higher Horizontal Resolution Models Perform Better?
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作者 Shoji KUSUNOKI 《Advances in Atmospheric Sciences》 2026年第1期259-262,共4页
Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(... Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(2025)].In relation to seasonal forecasting and climate projection in the East Asian summer monsoon season,proper simulation of the seasonal migration of rain bands by models is a challenging and limiting factor[section 7.1 in Wang et al.(2025)]. 展开更多
关键词 enhancing model resolution refinement data assimilation systems section climate model climate projection higher horizontal resolution seasonal forecasting simulation seasonal migration rain bands model resolution
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A Predictive Model for the Elastic Modulus of High-Strength Concrete Based on Coarse Aggregate Characteristics
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作者 LI Liangshun LI Huajian +2 位作者 HUANG Fali YANG Zhiqiang DONG Haoliang 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期121-137,共17页
To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the stre... To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the strength and elastic modulus of mortar and concrete prepared with mechanism aggregates of the corresponding lithology,and the stress-strain curves of concrete were investigated.In this paper,a coarse aggregate and mortar matrix bonding assumption is proposed,and a prediction model for the elastic modulus of mortar is established by considering the lithology of the mechanism sand and the slurry components.An equivalent coarse aggregate elastic modulus model was established by considering factors such as coarse aggregate particle size,volume fraction,and mortar thickness between coarse aggregates.Based on the elastic modulus of the equivalent coarse aggregate and the remaining mortar,a prediction model for the elastic modulus of the two and three components of concrete in series and then in parallel was established,and the predicted values differed from the measured values within 10%.It is proposed that the coarse aggregate elastic modulus in highstrength concrete is the most critical factor affecting the elastic modulus of concrete,and as the coarse aggregate elastic modulus increases by 27.7%,the concrete elastic modulus increases by 19.5%. 展开更多
关键词 elastic modulus prediction model MINERALOGICAL influence mechanism
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An effective deep-learning prediction of Arctic sea-ice concentration based on the U-Net model
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作者 Yifan Xie Ke Fan +2 位作者 Hongqing Yang Yi Fan Shengping He 《Atmospheric and Oceanic Science Letters》 2026年第1期34-40,共7页
Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiote... Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiotemporal distribution of Arctic SIC is more challenging than predicting its total extent.In this study,spatiotemporal prediction models for monthly Arctic SIC at 1-to 3-month leads are developed based on U-Net-an effective convolutional deep-learning approach.Based on explicit Arctic sea-ice-atmosphere interactions,11 variables associated with Arctic sea-ice variations are selected as predictors,including observed Arctic SIC,atmospheric,oceanic,and heat flux variables at 1-to 3-month leads.The prediction skills for the monthly Arctic SIC of the test set(from January 2018 to December 2022)are evaluated by examining the mean absolute error(MAE)and binary accuracy(BA).Results showed that the U-Net model had lower MAE and higher BA for Arctic SIC compared to two dynamic climate prediction systems(CFSv2 and NorCPM).By analyzing the relative importance of each predictor,the prediction accuracy relies more on the SIC at the 1-month lead,but on the surface net solar radiation flux at 2-to 3-month leads.However,dynamic models show limited prediction skills for surface net solar radiation flux and other physical processes,especially in autumn.Therefore,the U-Net model can be used to capture the connections among these key physical processes associated with Arctic sea ice and thus offers a significant advantage in predicting Arctic SIC. 展开更多
关键词 Arctic sea-ice concentration Deep-learning prediction U-Net model CFSv2 NorCPM
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Tail clamping induces anxiety-like behaviors and visceral hypersensitivity in rat models of non-erosive reflux disease
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作者 Mi Lv Xin Liu +6 位作者 Kai-Yue Huang Yu-Xi Wang Zheng Wang Li-Li Han Hui Che Lin Lv Feng-Yun Wang 《World Journal of Psychiatry》 2026年第1期356-368,共13页
BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models ... BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models are unclear.AIM To establish a translational NERD rat model with anxiety comorbidity via tail clamping and study corticotropin-releasing hormone(CRH)-mediated neuroimmune pathways in visceral hypersensitivity and esophageal injury.METHODS Sprague-Dawley(SD)and Wistar rats were grouped into sham,model,and modified groups(n=10 each).The treatments for the modified groups were as follows:SD rats received ovalbumin/aluminum hydroxide suspension+acid perfusion±tail clamping(40 minutes/day for 7 days),while Wistar rats received fructose water+tail clamping.Esophageal pathology,visceral sensitivity,and behavior were assessed.Serum CRH,calcitonin gene-related peptide(CGRP),5-hydroxytryptamine(5-HT),and mast cell tryptase(MCT)and central amygdala(CeA)CRH mRNA were measured via ELISA and qRT-PCR.RESULTS Tail clamping induced anxiety,worsening visceral hypersensitivity(lower abdominal withdrawal reflex thresholds,P<0.05)and esophageal injury(dilated intercellular spaces and mitochondrial edema).Both models showed raised serum CRH,CGRP,5-HT,and MCT(P<0.01)and CeA CRH mRNA expression(P<0.01).Behavioral tests confirmed anxiety-like phenotypes.NERD-anxiety rats showed clinical-like symptom severity without erosion.CONCLUSION Tail clamping induces anxiety in NERD models,worsening visceral hypersensitivity via CRH neuroimmune dysregulation,offering a translational model and highlighting CRH as a treatment target. 展开更多
关键词 Non-erosive reflux disease Anxiety and depression Animal model Tail-clamping Corticotropin hormones
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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Growing a Rural Future--A young Ugandan channels insights from China’s model villages to build a more resilient,cooperative and forward-looking Busoga
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作者 LI XIAOYU 《ChinAfrica》 2026年第1期56-57,共2页
In the lush heart of Uganda’s Busoga sub-region,Isaac Imaka is charting a new course for rural development.After seven years in national media,he left the newsroom and stepped into the soil.The former reporter with t... In the lush heart of Uganda’s Busoga sub-region,Isaac Imaka is charting a new course for rural development.After seven years in national media,he left the newsroom and stepped into the soil.The former reporter with the Daily Monitor was driven by the belief that communities like his in Jinja North deserved more than chronic poverty and hand-to-mouth survival. 展开更多
关键词 community resilience Uganda rural development model villages rural future Busoga sub region cooperative development rural journalism
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Effects of noninvasive brain stimulation on motor functions in animal models of ischemia and trauma in the central nervous system
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作者 Seda Demir Gereon R.Fink +1 位作者 Maria A.Rueger Stefan J.Blaschke 《Neural Regeneration Research》 2026年第4期1264-1276,共13页
Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of kn... Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation. 展开更多
关键词 noninvasive brain stimulation preclinical modeling STROKE transcranial direct current stimulation transcranial magnetic stimulation traumatic brain injury
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Risk factors for paternal perinatal depression in Chinese advanced maternal age couples:A regression mixture model
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作者 Xing Yin Juan Du +1 位作者 Shao-Lian Cai Xing-Qiang Chen 《World Journal of Psychiatry》 2026年第1期267-277,共11页
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn... BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support. 展开更多
关键词 Advanced maternal age Paternal perinatal depression Fathers’mental health Regression mixture model Advanced-age pregnancy Latent profile analysis
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Novel therapies for myasthenia gravis:Translational research from animal models to clinical application
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作者 Benedetta Sorrenti Christian Laurini +4 位作者 Luca Bosco Camilla Mirella Maria Strano Adele Ratti Yuri Matteo Falzone Stefano Carlo Previtali 《Neural Regeneration Research》 2026年第5期1834-1848,共15页
Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in ... Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in their serum, targeting acetylcholine receptor, muscle-specific kinase, or related proteins. Current treatment for myasthenia gravis involves symptomatic therapy, immunosuppressive drugs such as corticosteroids, azathioprine, and mycophenolate mofetil, and thymectomy, which is primarily indicated in patients with thymoma or thymic hyperplasia. However, this condition continues to pose significant challenges including an unpredictable and variable disease progression, differing response to individual therapies, and substantial longterm side effects associated with standard treatments(including an increased risk of infections, osteoporosis, and diabetes), underscoring the necessity for a more personalized approach to treatment. Furthermore, about fifteen percent of patients, called “refractory myasthenia gravis patients”, do not respond adequately to standard therapies. In this context, the introduction of molecular therapies has marked a significant advance in myasthenia gravis management. Advances in understanding myasthenia gravis pathogenesis, especially the role of pathogenic antibodies, have driven the development of these biological drugs, which offer more selective, rapid, and safer alternatives to traditional immunosuppressants. This review aims to provide a comprehensive overview of emerging therapeutic strategies targeting specific immune pathways in myasthenia gravis, with a particular focus on preclinical evidence, therapeutic rationale, and clinical translation of B-cell depletion therapies, neonatal Fc receptor inhibitors, and complement inhibitors. 展开更多
关键词 acetylcholine receptor(AChR) animal models B-cell depletion biological therapies COMPLEMENT IMMUNOTHERAPY muscle-specific kinase(Mu SK) neonatal Fc receptor
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Human cerebral organoids:Complex,versatile,and human-relevant models of neural development and brain diseases
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作者 Raquel Coronel Rosa González-Sastre +8 位作者 Patricia Mateos-Martínez Laura Maeso Elena Llorente-Beneyto Sabela Martín-Benito Viviana S.Costa Gagosian Leonardo Foti Ma Carmen González-Caballero Victoria López-Alonso Isabel Liste 《Neural Regeneration Research》 2026年第3期837-854,共18页
The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cereb... The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cerebral organoids have emerged as valuable tools offering a more complex,versatile,and human-relevant system than traditional animal models,which are often unable to replicate the intricate architecture and functionality of the human brain.Since human cerebral organoids are a state-of-the-art model for the study of neurodevelopment and different pathologies affecting the brain,this field is currently under constant development,and work in this area is abundant.In this review,we give a complete overview of human cerebral organoids technology,starting from the different types of protocols that exist to generate different human cerebral organoids.We continue with the use of brain organoids for the study of brain pathologies,highlighting neurodevelopmental,psychiatric,neurodegenerative,brain tumor,and infectious diseases.Because of the potential value of human cerebral organoids,we describe their use in transplantation,drug screening,and toxicology assays.We also discuss the technologies available to study cell diversity and physiological characteristics of organoids.Finally,we summarize the limitations that currently exist in the field,such as the development of vasculature and microglia,and highlight some of the novel approaches being pursued through bioengineering. 展开更多
关键词 assembloids BIOENGINEERING challenges disease modeling drug screening and toxicology human brain organoids human pluripotent stem cells neurodegenerative diseases NEURODEVELOPMENT VASCULARIZATION
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Suitability Assessment of Mononychellus tanajoa(Acari:Tetranychidae) in Yunnan Based on Maxent Model 被引量:4
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作者 卢辉 陈青 +1 位作者 卢芙萍 徐雪莲 《Agricultural Science & Technology》 CAS 2011年第12期1905-1908,共4页
[Objective] This study aimed to analyze the potential geography distribution of M.tanajoa in Yunnan.[Method] The suitability of M.tanajoa in Yunnan was studied in this paper using Maxent and ArcGIS,based on the biolog... [Objective] This study aimed to analyze the potential geography distribution of M.tanajoa in Yunnan.[Method] The suitability of M.tanajoa in Yunnan was studied in this paper using Maxent and ArcGIS,based on the biological data and known distribution of M.tanajoa,and meteorological data from years of 1950-2000 in WorldClim.[Result] The results showed that there were four levels of suitability assessment of M.tanajoa in Yunnan,in which western and eastern areas are in the most suitability,including part areas of Simao,Lincang,Baoshan,Nujiang,Diqing,Qujing and Wenshan areas.[Conclusion] The potential geographic distribution of M.tanajoa in Yunnan defined in this paper constructed the theory basis and technical support for scientifically forming of quarantine policy and measure for M.tanajoa in China. 展开更多
关键词 Mononychellus tanajoa YUNNAN Suitability assessment maxent
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基于MaxEnt的山东省恙虫病影响因素分析及风险区域预测
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作者 石兴龙 徐欣颖 +6 位作者 乔颖异 吕婧 岳芳 程传龙 左慧 鲁亮 李秀君 《中国病原生物学杂志》 北大核心 2026年第1期55-60,65,共7页
目的分析山东省恙虫病发病的影响因素,预测其高风险区域,为恙虫病的精准防控提供科学依据。方法选取2017-2021年山东省恙虫病报告病例数据,收集同期气象、环境和社会经济因素数据;计算各影响因素间Spearman相关系数分析相关性;构建最大... 目的分析山东省恙虫病发病的影响因素,预测其高风险区域,为恙虫病的精准防控提供科学依据。方法选取2017-2021年山东省恙虫病报告病例数据,收集同期气象、环境和社会经济因素数据;计算各影响因素间Spearman相关系数分析相关性;构建最大熵模型(Maximum entropy model,MaxEnt),评估各影响因素对恙虫病发生的相对贡献,通过影响因素的响应曲线反映恙虫病的发生与影响因素之间的关联,预测高风险区域,绘制风险区域分布图,通过受试者工作特征(Receiver operating characteristic,ROC)曲线与曲线下面积(Area under curve,AUC)评估模型预测效果。结果2017-2021年山东省共报告3355例恙虫病病例,发病率较高的地区主要集中在山东省中南部及东部,北部与西部地区发病率较低,发病高峰在10~11月,男女性别比为1∶1.27,50岁以上老人占比最多(81.31%),农民是发病最多的职业(89.63%)。MaxEnt模型结果显示,归一化植被指数(Normalized difference vegetation index,NDVI)、相对湿度、年平均温度、海拔、坡度对恙虫病的发生有着较大贡献(累计贡献度86.10%),NDVI对恙虫病发病贡献度最大(37.80%),与恙虫病发病呈倒“U”型关系。模型预测的高风险区域主要集中在山东省中南部及胶东半岛地区,在西部和北部预测有零散分布。ROC曲线结果表明模型具有良好的预测性能(AUC=0.839)。结论山东省恙虫病受多种因素的影响,NDVI、相对湿度、年平均温度、海拔、坡度是影响恙虫病发生的主要因素,山东省中南部及东部地区是恙虫病发生的高风险地区。应加强环境监测和健康教育,针对高风险地区开展精准防控措施。 展开更多
关键词 恙虫病 最大熵模型 影响因素 风险区域
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基于CMIP6和MaxEnt模型的江淮一季稻适生区分布预估
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作者 王胜 陈健 +6 位作者 周宇 孙佳丽 翟振芳 谢五三 戴娟 丁小俊 吴蓉 《气候变化研究进展》 北大核心 2025年第6期766-776,共11页
基于CMIP6气候模式数据和MaxEnt模型,耦合土壤、地形及人类活动等多维环境因子,系统评估了江淮一季稻在气候基准期(1985—2014年)与未来(2026—2100年)不同情景下适生区演变。结果表明:(1)通过共线性检验结合刀切法的“双指标”机制,从1... 基于CMIP6气候模式数据和MaxEnt模型,耦合土壤、地形及人类活动等多维环境因子,系统评估了江淮一季稻在气候基准期(1985—2014年)与未来(2026—2100年)不同情景下适生区演变。结果表明:(1)通过共线性检验结合刀切法的“双指标”机制,从14个潜在环境因子中优选出9个主导因子,其累计贡献率达94.4%。模型验证表明,优化后的MaxEnt模型预测精度显著提升(AUC=0.923)。(2)未来江淮一季稻全生育期平均气温呈现显著上升趋势,其中SSP5-8.5情景下的升温速率最大(0.50℃/(10 a));降水量总体呈增加趋势,江淮地区中北部降水增加趋势高于南部。(3)气候基准期高适生区集中在长江三角洲和沿江平原,占总面积的21.7%,其典型特征为水稻土占比高且水热条件优越;中适生区集中分布在淮河以南平原区,占26.2%;低适生区分布在淮北平原,占35.1%;非适生区主要包括大别山区和皖南山区、西北部旱地及城市化区域,占17.1%。(4)在未来时期,适生区呈现“东缩北扩”趋势,至SSP5-8.5情景下的远期,高适生区面积减少3.8个百分点,低适生区面积增加6.6个百分点。该演变主要受气候变暖“双刃剑”效应驱动:一方面安徽北部(32°N以北)因≥10℃积温增加300~450℃∙d、生育期延长12~18 d成为主要扩展区;另一方面江苏南部(32°N以南)受高温日数增至35~45 d的胁迫,特别是在水稻关键生育期(孕穗-抽穗期)遭遇极端高温的概率增加3~5倍,因而适生区显著退缩。建议通过耐高温品种选育和种植布局优化提升气候韧性,为区域农业适应性策略制定提供科学依据。 展开更多
关键词 江淮一季稻 适生区 气候变化预估 maxent模型
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基于MaxEnt模型对泰顺县多花黄精适生区的预测及评估 被引量:1
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作者 姜武 张立华 +1 位作者 刘雷雷 章书声 《浙江农业科学》 2025年第1期216-223,共8页
多花黄精野外资源匮乏,市场需求量大,研究泰顺多花黄精的生态适生性具有重要意义。该研究收集并筛选出29份多花黄精野外自然分布点位和8个环境变量,构建MaxEnt模型,模型拟合度高。结果表明,海拔、9月太阳辐射、年均温度变化范围、最冷... 多花黄精野外资源匮乏,市场需求量大,研究泰顺多花黄精的生态适生性具有重要意义。该研究收集并筛选出29份多花黄精野外自然分布点位和8个环境变量,构建MaxEnt模型,模型拟合度高。结果表明,海拔、9月太阳辐射、年均温度变化范围、最冷季度降水量、pH值、8月平均温度是影响多花黄精分布的主导环境变量。对多花黄精4个适生区在泰顺县19个乡镇的分布面积进行重分类,发现泰顺县内多花黄精的高适生面积为63.01 km^(2),其中罗阳镇、龟湖镇、司前镇、泗溪镇和竹里镇排行前列。该模型结果可靠,建议在多花黄精高适生区做好野生资源保护及人工规范化栽培。 展开更多
关键词 多花黄精 生态适生性 maxent模型 刀切法
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基于MaxEnt模型的四川省高原鼠兔潜在地理分布预测
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作者 张绪校 李其 +6 位作者 鲁岩 李国和 贾玉珍 杨廷勇 姚建民 袁小情 陈丽丽 《草学》 2025年第3期59-65,共7页
分析了2022—2024年四川省高原鼠兔调查数据,使用Max Ent模型分析了四川省高原鼠兔(Ochotona curzoniae)潜在分布区并划分了适生区,建立了高原鼠兔分布概率与夹捕率指数模型,计算了各夹捕率区间的分布面积。结果显示:全省高原鼠兔分布... 分析了2022—2024年四川省高原鼠兔调查数据,使用Max Ent模型分析了四川省高原鼠兔(Ochotona curzoniae)潜在分布区并划分了适生区,建立了高原鼠兔分布概率与夹捕率指数模型,计算了各夹捕率区间的分布面积。结果显示:全省高原鼠兔分布于海拔3208~4786 m之间,平均海拔4044.0±10.7 m。Max Ent模型精度AUC值达到0.936。高原鼠兔夹捕率小于10%的县为21个,面积748.1×10^(4) hm^(2),占总分布面积的81.7%;夹捕率大于10%的县共10个,面积共167.1×10^(4) hm^(2),占总分布面积的18.3%。本文首次运用生态位模型在四川省针对高原鼠兔进行了潜在分布区划分和面积计算,并建立了夹捕率计算模型,分析结果与历年高原鼠兔的调查情况吻合度较高。本文为高原鼠兔的监测预报和防治工作提供了参考数据,同时为高原鼠兔及其他草原有害生物的监测预报工作提供了一种思路和方法。 展开更多
关键词 高原鼠兔 maxent模型 夹捕率
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基于优化MaxEnt模型的湖北省黄连潜在适生区预测
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作者 刘少华 张祯志 陈小慧 《长江大学学报(自然科学版)》 2025年第5期123-130,共8页
基于生态位理论,结合气候变化背景下的适宜性预测需求,对湖北省黄连(Coptis chinensis)的潜在适生区进行了动态预测与分析。以最大熵(MaxEnt)模型为基础,融合地理信息系统(GIS)空间分析技术,引入环境变量进行多重共线性筛选(基于Pearso... 基于生态位理论,结合气候变化背景下的适宜性预测需求,对湖北省黄连(Coptis chinensis)的潜在适生区进行了动态预测与分析。以最大熵(MaxEnt)模型为基础,融合地理信息系统(GIS)空间分析技术,引入环境变量进行多重共线性筛选(基于Pearson相关性分析)及模型参数优化(正则化乘数1.5,特征组合LPQH)。采用筛选后的11个生物气候变量与地形数据,结合k折交叉验证(k=10),预测当前及未来(SSP-245情景下)湖北省黄连潜在适生区分布格局。结果显示,海拔(贡献度52.8%)、年平均降水量(贡献度11.1%)和最冷月最低温(贡献度10.5%)为黄连分布的主导环境变量。当前高适生区面积为6643.29 km^(2),主要集中于恩施、十堰和神农架地区。未来至2061—2080年,高适生区呈“先增后稳”趋势(峰值7048.14 km^(2)),中适生区面积波动下降,适生区质心在30.92°N附近呈小幅东西向迁移。模型AUC值为0.911±0.027,表明预测精度较高。研究提出的优化方法与生态解释框架可为中药材种植适地性评估及气候变化背景下物种资源保护提供参考。 展开更多
关键词 maxent模型 黄连(Coptis chinensis) 潜在适生区 预测 GIS
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基于MaxEnt模型预测瓜类细菌性果斑病在中国的潜在地理分布 被引量:4
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作者 张文瑶 陈雪荣 +2 位作者 谢洪芳 田艳丽 胡白石 《植物保护》 北大核心 2025年第1期102-110,122,共10页
瓜类细菌性果斑病(bacterial fruit blotch)是瓜类作物上重要的种传细菌性病害,病原菌为西瓜噬酸菌Acidovorax citrulli。我国是全球西甜瓜的主要生产区。近年来,瓜类细菌性果斑病的频繁发生已严重影响我国西甜瓜产业的健康发展。为明... 瓜类细菌性果斑病(bacterial fruit blotch)是瓜类作物上重要的种传细菌性病害,病原菌为西瓜噬酸菌Acidovorax citrulli。我国是全球西甜瓜的主要生产区。近年来,瓜类细菌性果斑病的频繁发生已严重影响我国西甜瓜产业的健康发展。为明确瓜类细菌性果斑病在我国的适生性,根据其在全球的最新分布数据,本研究利用MaxEnt模型结合ArcGIS软件预测了瓜类细菌性果斑病在我国的潜在地理分布。结果表明,MaxEnt模型的平均AUC(area under curve,AUC)值均大于0.9,预测结果的准确性较高。在历史气候条件下,瓜类细菌性果斑病适生区分布广泛,主要包括华中、华南和华东地区,以及部分华北、东北地区,占我国面积的47.36%。影响瓜类细菌性果斑病在我国潜在分布区域的主要气候因子包括最热月份最高温度、月平均昼夜温差、最干月份降水量和最干季平均温度。未来气候情景无论是低环境强迫还是高环境强迫,适生区面积均呈现增长的趋势,预示着随着气候的变化,瓜类细菌性果斑病在我国发生的风险不断增加,因此建议应加强检疫监测和防控,严防其扩散。 展开更多
关键词 瓜类细菌性果斑病 maxent模型 气候变化 潜在地理分布
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