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Sharp Bounds for ABS Index of Line,Total and Mycielski Graphs
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作者 YE Qingfang LI Fengwei 《数学进展》 北大核心 2026年第1期45-59,共15页
The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isome... The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isomers,such as boiling point,of formation are found to be better measured by the ABS index than by the Randi,atom-bond connectivity(ABC),and sum-connectivity(SC)indices.One important source of information for researching the molecular structure is the bounds for its topological indices.The extrema of the ABS index of the line,total,and Mycielski graphs are calculated in this work.Moreover,the pertinent extremal graphs were illustrated. 展开更多
关键词 ABS index line graph total graph Mycielski graph
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Vulnerability assessment in fractured aquifer using improved vulnerability index:Applied to Gabes aquifer,Southeastern Tunisia
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作者 Mounir Atoui Belgacem Agoubi 《Journal of Groundwater Science and Engineering》 2026年第1期69-82,共14页
The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims ... The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims to develop a hybrid model that combines the Fracture Aquifer Index(FAI)with the conventional GOD(Groundwater occurrence,Overall lithology,Depth to water table)method,to assess groundwater vulnerability in fractured aquifer.To develop the hybrid model,the classical GOD method was integrated with FAI to produce a single composite index.Each parameter within both GOD and FAI was scored,and a final index was calculated to delineate vulnerable areas.The results show that the study area can be classified into four vulnerability levels:Very low,low,moderate,and high,indicating that approximately 8%of the area exhibits very low vulnerability,29%has low vulnerability,25%falls into the moderate category,and 38%is considered highly vulnerable.The FAI-GOD model further incorporates fracture network characteristics.This refinement reduces the classification to three vulnerability classes:Low,medium,and high.The outcomes demonstrate that 46%of the area is highly vulnerable due to a dense concentration of fractures,while 17%represents an intermediate zone characterized by either shallow or deeper fractures.In contrast,37%corresponds to areas with lightly fractured rock,where the impact on vulnerability is minimal.Multivariate statistical analysis was employed using Principal Components Analysis(PCA)and Hierarchical Cluster Analysis(HCA)on 24 samples across six variables.The first three components account for over 76%of the total variance,reinforcing the significance of fracture dynamics in classifying vulnerability levels.The FAI-GOD model removes the very-low-vulnerability class and expands the spatial extent of low-and high-vulnerability zones,reflecting the dominant influence of fracture networks on aquifer sensitivity.While both indices use a five-class system,FAI-GOD redistributes vulnerability by eliminating very-low-vulnerability areas and amplifying low/high categories,highlighting the critical role of fractures.A strong correlation(R2=0.94)between the GOD and FAI-GOD indices,demonstrated through second-order polynomial regression,confirms the robustness of the FAI-GOD model in accurately predicting vulnerability to pollution.This model provides a useful framework for assessing the vulnerability of complex aquifers and serves as a decision-making tool for groundwater managers in similar areas. 展开更多
关键词 GROUNDWATER Aquifer vulnerability Fractured media FAI-GOD index GOD index GIS
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Instruction for Authors
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《Journal of Iron and Steel Research International》 2026年第1期500-500,共1页
Journal of Iron and Steel Research International,sponsored by China Iron and Steel Research Institute Group,is an academic journal which provides an international medium for publication of original research articles,r... Journal of Iron and Steel Research International,sponsored by China Iron and Steel Research Institute Group,is an academic journal which provides an international medium for publication of original research articles,reviews and letters in the fields of metallurgy and metallic materials.It has been covered by Science Citation Index(SCI)and Engineering Index(EI)since 1996 and 2016,respectively. 展开更多
关键词 iron steel LETTERS original research articles METALLURGY metallic materials science citation index REVIEWS engineering index
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Human development and gender inequality are associated with cardiorespiratory fitness:A global systematic review of VO_(2peak)
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作者 Nicolas J.Pillon Joaquin Ortiz de Zevallos +1 位作者 Juleen R.Zierath Barbara E.Ainsworth 《Journal of Sport and Health Science》 2026年第3期27-36,共10页
Background:Cardiorespiratory fitness(CRF)is a powerful predictor of mortality and chronic disease risk,yet global patterns and determinants of CRF remain poorly defined,particularly in females and underrepresented pop... Background:Cardiorespiratory fitness(CRF)is a powerful predictor of mortality and chronic disease risk,yet global patterns and determinants of CRF remain poorly defined,particularly in females and underrepresented populations.We conducted a systematic review and quantitative synthesis of directly measured peak oxygen uptake(VO_(2peak))internationally and examined its association with human development and gender ine quality.Methods:Studies were eligible if VO_(2peak)was assessed via direct gas analysis during maximal exercise testing,and if the countries had scores for the Human Development Index(HDI)and Gender Inequality Index(GII).Studies were identified through MEDLINE/PubMed,Embase,CINAHL,and Web of Science.Risks of bias were assessed by an adaptation of the Newcastle-Ottawa Scale.Multivariable linear regression models examined associations between VO_(2peak),age,sex,exercise modality,HDI,GII,and study year.Results:Data included 95 studies from 24 countries with HDI and GII scores,comprising 119,435 adults(42%females)with VO_(2peak)assessed via direct gas analysis during maximal exercise testing.The risk of bias was low.VO_(2peak)was positively associated with HDI(β=14.1)and negatively associated with GII(β=-3.6).Slightly stronger associations were observed in females than males(HDI:β=18.9 vs.β=13.9,GII:β=-4.6vs.β=-3.6).Young females in middle-HDI countries had higher VO_(2peak)than those in low-HDI countries(31.2mL/kg/min vs.28.5 mL/kg/min),with limited additional gams in high-HDI contexts.VO_(2peak)decreased with higher gender inequality,with the largest disparities observed in young females between high-and low-GII countries(26.3 mL/kg/min vs.32.8 mL/kg/min).Conclusion:Global variation in CRF is tied to national levels of human development and gender equality.These findings support prioritizing structural and policy-level interventions that address social and gender disparities in physical activity access and health promotion.Studies from countries with lower HDI and information on ethnicity and socioeconomic status will bridge crucial gaps in understanding factors involved in global CRF levels. 展开更多
关键词 Human development index Gender inequality index Oxygen uptake INTERNATIONAL Physical activity
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The triglyceride-glucose index shows promise as a novel prognostic marker for advanced hepatocellular carcinoma
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作者 Tao Xu Xu Qi +1 位作者 Fei-Yu Zhao Nian-Song Qian 《World Journal of Gastroenterology》 2026年第2期167-169,共3页
This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma pa... This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma patients undergoing combined camrelizumab and lenvatinib therapy.While we acknowledge the study’s clinical relevance in proposing an easily accessible metabolic biomarker,we delve into the mechanistic plausibility linking insulin resistance to immunotherapy response and angiogenic inhibition.We further critically examine the methodological limitations,including the retrospective design,the populationspecific TyG cut-off value,and unaddressed metabolic confounders.We highlight the imperative for future research to validate its utility across diverse etiologies and treatment settings,and to unravel the underlying immunometabolic pathways. 展开更多
关键词 Triglyceride-glucose index Prognostic marker Advanced hepatocellular carcinoma Camrelizumab Lenvatinib
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Causal effect of obesity on cataract and mediating roles of metabolites:a Mendelian randomization study
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作者 Chen Li Jiao-Man Wang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 2026年第3期564-574,共11页
AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide asso... AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide association studies to examine the relationship between obesity and cataract were utilized.Obesity-related traits,including body mass index(BMI),waist-to-hip ratio(WHR),and waist circumference(WC).A two-sample MR approach was employed to assess the causal effect of obesity on cataract risk,while potential mediators were identified from suitable genome-wide association studies(GWAS)datasets.Additionally,a metabolic pathway analysis was conducted.RESULTS:An increase of 1 standard deviation(SD)in BMI,WHR,and WC was associated with a significantly higher risk of cataract(BMI:odds ratio(OR)1.0017,95%confidence interval(CI):1.0001-1.0032,P=0.0320;WHR:OR 1.0029,95%CI:1.0006-1.0051,P=0.0129;WC:OR 1.0020,95%CI:1.0001-1.0038,P=0.0390].These associations remained robust after adjusting for confounding factors in multivariable MR analysis.Furthermore,a two-step MR analysis identified eight potential metabolic mediators,with one mediator showing a significant causal role in the relationship between obesity and cataract.CONCLUSION:This work highlights the importance of addressing obesity as a modifiable risk factor for cataracts,particularly through metabolic pathways. 展开更多
关键词 OBESITY CATARACT Mendelian randomization body mass index waist-to-hip ratio waist circumference
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Construction of a mental health literacy evaluation index system for adolescents with mental disorders
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作者 Ying-Qiong Ge Xiao-Shuang Ouyang +2 位作者 Zheng-Min Zhu Bi-Can Tan Xiao-Jian Jiang 《World Journal of Psychiatry》 2026年第1期299-311,共13页
BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an e... BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an evaluation index system for the mental health literacy of adolescent patients with mental disorders,providing a scientific,comprehensive,and reliable tool for the monitoring and intervention of mental health literacy of such patients.METHODS From December 2022 to June 2023,the evaluation index system for mental health literacy of adolescents with mental disorders was developed through literature reviews,semi-structured interviews,expert letter consultations,and the analytic hierarchy process.Based on this index system,a self-assessment questionnaire was compiled and administered to 305 adolescents with mental disorders to test the reliability and validity of the index system.RESULTS The final evaluation index system for mental health literacy of adolescents with mental disorders included 4 first-level indicators,10 second-level indicators,and 52 third-level indicators.The overall Cronbach’sαcoefficient of the index system was 0.957,with a partial reliability of 0.826 and a content validity index of 0.975.The cumulative variance contribution rate of 10 common factors was 66.491%.The correlation coefficients between each dimension and the total questionnaire ranged from 0.672 to 0.724,while the correlation coefficients in each dimension ranged from 0.389 to 0.705.CONCLUSION The evaluation index system for mental health literacy of adolescents with mental disorders,developed in this study,demonstrated notable reliability and validity,making it a valuable tool for evaluating mental health literacy in this population. 展开更多
关键词 Adolescents Mental disorders Mental health literacy Evaluation index system Delphi method
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Muscle mass correlates with rocuronium distribution volume and guides dose optimization in obese colorectal cancer patients
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作者 Zhan-Wen Li Zhe Liu Sheng-Qun Liu 《World Journal of Gastrointestinal Oncology》 2026年第1期176-189,共14页
BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic... BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients. 展开更多
关键词 Obesity ROCURONIUM Skeletal muscle index Population pharmacokinetics Individualized dosing Colorectal cancer SARCOPENIA
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关键词标引的规范化
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作者 本刊编辑部 《中国微侵袭神经外科杂志》 2026年第2期118-118,共1页
关键词指论文中最能反映主题信息的特征词汇或词组、短语。我国国家标准规定,对论文的标引使用“关键词”一词,关键词中包括主题词和(或)副主题词以及少数自由词。生物医学领域使用频繁、而且又被使用者认可的主题词,约有15000个;每年... 关键词指论文中最能反映主题信息的特征词汇或词组、短语。我国国家标准规定,对论文的标引使用“关键词”一词,关键词中包括主题词和(或)副主题词以及少数自由词。生物医学领域使用频繁、而且又被使用者认可的主题词,约有15000个;每年最新版美国国立图书馆编辑的《Index Medicus》中医学主题词表(MeSH)内所列的词均有所增删。标引关键词的主要工具书为《医药学名词与主题词(MeSH)对应表》(中国医学科学院医学信息研究所)。若主题词表尚无相应的词,则通常采取选用上位词、同义词,或采用组配等办法。 展开更多
关键词 标引 特征词汇 生物医学 Index Medicus
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Frontiers of Nursing Call for Papers
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《Frontiers of Nursing》 2026年第1期F0003-F0003,共1页
Frontiers of Nursing is a nursing academic journal,CN 14-1395/R,ISSN 2097-5368.Size A4,quarterly publication,color printing,public offerings at home and abroad which is managed by the First Hospital of Shanxi Medical ... Frontiers of Nursing is a nursing academic journal,CN 14-1395/R,ISSN 2097-5368.Size A4,quarterly publication,color printing,public offerings at home and abroad which is managed by the First Hospital of Shanxi Medical University,sponsored by Shanxi Nursing Association and Shanxi Medical Periodical Press Co.,Ltd.Frontiers of Nursing has been indexed by databases including Scopus,Google Scholar,DOAJ,Baidu Scholar,CNKI,VIP,Wanfang,Chaoxing,and so on. 展开更多
关键词 sponsored indexed databases NURSING academic journal quarterly publication color printing frontiers nursing managed
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Threat assessment of non-cooperative satellites in interception scenarios:A transfer window perspective
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作者 Hongyu Han Zhaohui Dang 《Defence Technology(防务技术)》 2026年第2期172-183,共12页
This paper proposes a threat assessment framework for non-cooperative satellites by analyzing their motion characteristics,developing a quantitative evaluation methodology,and demonstrating its effectiveness via repre... This paper proposes a threat assessment framework for non-cooperative satellites by analyzing their motion characteristics,developing a quantitative evaluation methodology,and demonstrating its effectiveness via representative scenarios with neural network acceleration.The framework first establishes a threat evaluation model that integrates three core parameters:capability,opportunity,and hidden values.Subsequently,this research systematically investigates the critical role of transfer windows in threat quantification and introduces a transfer window-based threat assessment approach.The proposed methodology is validated through multiple representative scenarios,with simulation results demonstrating superior performance compared to conventional methods relying solely on optimal transfer windows or minimum distance metrics,enabling more nuanced threat ranking in scenarios where traditional techniques prove inadequate.To address computational demands,a neural networkbased approximation system is implemented to achieve a 25,200×speedup(0.005 s vs.baseline 126 s per 1000-sample batch)through parallel processing,maintaining 99.3%accuracy.Finally,the study explores the framework's extensibility to diverse NCS objectives.It identifies discrepancies between intention inference models and threat evaluation paradigms,providing methodological insights for next-generation space domain awareness systems. 展开更多
关键词 Non-cooperative target Orbital maneuver Orbital service Threat index Threat prediction
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A numerical study of hemodynamic effects on arteriovenous fistula calcification
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作者 Zhe Wang Huihui Ning +4 位作者 Lihua Wang Yaohong Wang Dekui Yuan Hewen Li Yingxue Lv 《Acta Mechanica Sinica》 2026年第1期344-354,共11页
Arteriovenous fistula(AVF)calcification is a common complication in hemodialysis patients that leads to AVF dysfunction and decreases the AVF survival,but the mechanisms of AVF calcification,especially the role of hem... Arteriovenous fistula(AVF)calcification is a common complication in hemodialysis patients that leads to AVF dysfunction and decreases the AVF survival,but the mechanisms of AVF calcification,especially the role of hemodynamic changes in AVF calcification have not been fully investigated.In this study,a computational fluid dynamics(CFD)model was carried out based on AVF,at the distal anastomosis of the cephalic vein and radial artery,generated from a patient-specific computed tomography(CT)angiography and Doppler ultrasound image.Hemodynamic factors were considered to explore the mechanisms responsible for the initiation and progression of AVF calcification.Five stages in one cardiac cycle were chosen to be studied for the velocity field,pressure,time-averaged wall shear stress(TAWSS),and oscillatory shear index(OSI).Blood pressure was higher in the arteriovenous anastomosis,and variations of great amplitude of pressure were examined during the cardiac cycle.Blood pressure,transient shear stress,TAWSS,and OSI were higher in the arteriovenous anastomosis and at the bottom of expanded outflow vein,and these sites were highly consistent with the calcified areas shown on CT angiography.On the contrary,no calcification was found in sites where streamline was stable,blood pressure did not change dramatically,as well as TAWSS and OSI were lower.It was shown that AVF calcification was correlated with hemodynamic changes,which may contribute to further understanding the mechanisms of AVF calcification and providing scientific evidence to inform the optimization of surgical strategies and the development of personalized interventional measures in clinical contexts. 展开更多
关键词 Arteriovenous fistula Vascular calcification HEMODYNAMICS Wall shear stress Oscillatory shear index
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Local Characterizations of Results on the Normal Index of Subgroups in Finite Groups
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作者 Yubo LV Yangming LI Xiaoxia DONG 《Journal of Mathematical Research with Applications》 2026年第1期33-39,共7页
Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divide... Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divides the order of a group G.In this paper,some characterizations of G being p-solvable or p-supersolvable were obtained by analyzing the normal index of certain subgroups of G.These results can be viewed as local version of recent results in the literature. 展开更多
关键词 p-solvable group p-supersolvable group normal index maximal subgroup 2-maximal subgroup
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The Brazilian risk assessment severity index score:a novel tool for predicting in-hospital mortality in emergency departments
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作者 Paulo Henrique Reis Negreiros Mariana Rebello Hilgert +3 位作者 Bruno Guerra Maurício de Carvalho Hugo Manuel Paz Morale Gustavo Lenci MarquesFederal University of Paraná(UFPR) 《World Journal of Emergency Medicine》 2026年第2期154-161,共8页
BACKGROUND:Rapid identification of patients at risk of clinical deterioration(in-hospital mortality) in emergency settings is essential for timely and appropriate care.Existing prognostic scores,such as the Acute Phys... BACKGROUND:Rapid identification of patients at risk of clinical deterioration(in-hospital mortality) in emergency settings is essential for timely and appropriate care.Existing prognostic scores,such as the Acute Physiology and Chronic Health Evaluation IV(APACHE IV),Simplified Acute Physiology Score 3(SAPS 3),Sequential Organ Failure Assessment(SOFA),and National Early Warning Score 2(NEWS 2),have limitations in emergency scenarios,particularly in resource-limited settings.We aimed to develop a simple and efficient tool tailored to the Brazilian healthcare system.METHODS:This retrospective,multicenter,cohort study analyzed data from 50,709 adult patients admitted to 12 hospitals in southern and southeastern Brazil between 2019 and 2020.The BRASIL score(Brazilian Risk Assessment Severity Index and Length of stay) was constructed using demographic and clinical variables available at admission.Logistic regression was used to determine the weight of each variable,and each variable was assigned a point value based on its β-coefficient and clinical relevance,with thresholds defined according to established medical cutoffs and statistical performance.The score's predictive accuracy was validated using the area under the receiver operating characteristic curve(AUC) with comparative analysis against NEWS 2.RESULTS:The BRASIL score,including age,sex,respiratory rate,heart rate,oxygen saturation,blood pressure,and body temperature,was derived through variables independently associated with in-hospital mortality in a multicenter cohort.The total score was stratified into three risk categories — low(0–3 points),moderate(4–7 points),and high(>7 points) — using observed inflection points in mortality distribution to optimize discrimination.This stratification demonstrated a stepwise increase in mortality rates across categories and the discriminatory performance,with an overall AUC of 0.743(95% CI:0.726–0.761).Compared to NEWS 2(AUC 0.697,95% CI:0.683–0.711),the BRASIL score offered superior early risk identification,supporting timely clinical decisionmaking and resource allocation in the emergency setting.CONCLUSION:The BRASIL score is a novel tool for predicting in-hospital mortality in emergency departments.Its predictive performance and ease of use suggest that it has the potential to improve patient outcomes. 展开更多
关键词 Cohort study Logistic regression Severity index In-hospital mortality Hospital resource management
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Evaluation of Heavy Metal Contamination in Soils of Vegetable Cultivation Bases in Zunyi City
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作者 Zhangyu ZHAO Wenzhao LI +5 位作者 Xiong YAN Xiao WANG Pingfan WU Meiju WANG Shoumei WU Nana WANG 《Asian Agricultural Research》 2026年第1期33-35,共3页
[Objectives]To analyze the current status of heavy metal contamination in soils of vegetable cultivation bases located in Huichuan District,Zunyi City.[Methods]Soil samples from various depths within the vegetable cul... [Objectives]To analyze the current status of heavy metal contamination in soils of vegetable cultivation bases located in Huichuan District,Zunyi City.[Methods]Soil samples from various depths within the vegetable cultivation bases of Guanba Village,Sidu Village,and Banqiao Village in Huichuan District,Zunyi City,were selected as the subjects of this study.The concentrations of five heavy metals,including lead(Pb),mercury(Hg),cadmium(Cd),arsenic(As),and chromium(Cr),were measured at different soil depths.The Nemerow comprehensive pollution index method was employed to assess heavy metal contamination,and the analysis was conducted in accordance with the farmland environmental quality evaluation standards for edible agricultural products.[Results]The concentrations of Cd and As at the sample collection sites were relatively elevated.The pollution level of Cd reached grade III or above,indicating moderate contamination in certain topsoil areas.Most As concentrations corresponded to grade II and grade III pollution levels.In contrast,Hg,Pb,and Cr concentrations remained within the safety standards established for agricultural products.However,Cd and As levels predominantly surpassed these safety thresholds.Notably,Guanba Village and Sidu Village exhibited significant pollution levels,warranting comprehensive investigations into the sources of contamination.[Conclusions]This study offers valuable insights for advancing the sustainable development of local agriculture and for the prevention and management of soil contamination. 展开更多
关键词 Heavy metal contamination Nemerow index VEGETABLE
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Conservation priority for protected areas in Fuzhou,southeast China:An integrated inside-out approach based on ecological network
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作者 CAI Xinyu XU Zesong +2 位作者 YOU Weibin KATTEL Giri WANG Yingzi 《Journal of Mountain Science》 2026年第1期327-342,共16页
Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identificat... Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identification and remediation of regional conservation gaps.To this end,we introduce the Framework for Conservation Priority Identification(FCPI).The framework integrates Morphological Spatial Pattern Analysis(MSPA),the Remote Sensing Ecological Index(RSEI),Circuit Theory,and the Minimum Cumulative Resistance(MCR)model to formulate a multidimensional conservation priority index.This index facilitates the identification of critical ecological network components and enables the dynamic prioritization of conservation efforts.A case study of Fuzhou City from 2014 to 2020 reveals that despite an overall improvement in regional environmental quality,the functionality of core ecological sources has markedly declined.Between 2014 and 2020,the number of ecological sources grew by 76.9%,yet their total area shrank by 13.9%.Concurrently,the number of ecological corridors rose from 27 to 53,extending their total length by 380.23 km,which indicates an intensifying trend of habitat fragmentation.Furthermore,a significant number of crucial ecological network nodes,particularly within Minhou County,lie explicitly outside the existing protected area system.This confirms the presence of conservation gaps and unveils the spatiotemporal dynamics of shifting conservation priorities.The research validates that the proposed FCPI can effectively diagnose the dynamic deficiencies within conservation systems.It offers scientific decisionsupport for local governments,facilitating a transition from isolated conservation efforts towards systematic and comprehensive ecological network governance. 展开更多
关键词 Conservation prioritization Ecological corridors Protected areas Remote sensing ecological index Landscape connectivity
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Multi-scale analysis of spatiotemporal evolution and driving factors of eco-environmental quality in a Ningxia irrigation district,China
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作者 LI Zequan CHAI Mingtang +4 位作者 ZHU Lei HE Junjie DING Yimin XU Fengkun XU Xiyuan 《Journal of Geographical Sciences》 2026年第2期471-493,共23页
The Qingtongxia Irrigation District in Ningxia is an important hydrological and ecological region.To assess its ecological environment quality from 2001 to 2021 across multiple scales and identify driving factors,a mo... The Qingtongxia Irrigation District in Ningxia is an important hydrological and ecological region.To assess its ecological environment quality from 2001 to 2021 across multiple scales and identify driving factors,a modified remote sensing ecological index(MRSEI)was developed by incorporating evapotranspiration.Spatial and temporal patterns were analyzed using the coefficient of variation,spatial autocorrelation,and semi-variogram methods,while influencing factors were explored via the optimal parameter geographical detector model.The MRSEI’s first principal component loadings and rankings aligned with those of RSEI(average contribution:81.31%),effectively reflecting spatiotemporal variations.At sub-irrigation district and landscape scales,ecological quality was slightly lower than at the district level but remained stable.Moderate and good ecological grades accounted for 36.28%and 33.38%of the area,respectively,at the district scale,and the moderate grade reached 70.48%on smaller scales.Spatial heterogeneity intensified with decreasing scale,and human activity lost explanatory power below a 5 km range.Human factors mainly drove ecological differentiation at the district scale,while natural factors dominated at finer scales.The MRSEI offers a novel tool for ecological assessment in arid/semi-arid areas and supports scale-adapted ecological protection strategies. 展开更多
关键词 ecological environment quality multi-scales remote sensing ecological index spatial heterogeneity semi-variance function
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Systemic inflammatory markers in gastric ulcer:Leveraging routine blood tests
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作者 Jin-Wei Zhang 《World Journal of Gastroenterology》 2026年第1期1-7,共7页
Gastric ulcer(GU)represents a clinically significant manifestation of peptic ulcer disease,driven by a complex interplay of microbial,environmental,and immuneinflammatory factors.A recent cross-sectional study by Shen... Gastric ulcer(GU)represents a clinically significant manifestation of peptic ulcer disease,driven by a complex interplay of microbial,environmental,and immuneinflammatory factors.A recent cross-sectional study by Shen et al systematically evaluated six complete blood count-derived inflammatory indices:Neutrophil-tolymphocyte ratio,monocyte-to-lymphocyte ratio,platelet-to-lymphocyte ratio,systemic immune-inflammation index,systemic inflammatory response index(SIRI),and aggregate index of systemic inflammation and demonstrated their positive associations with GU prevalence,identifying SIRI as the strongest predictor.This editorial contextualizes these findings within the broader literature,clarifies that these indices reflect systemic rather than GU-specific inflammation,highlights methodological strengths and major limitations,and proposes a conceptual clinical algorithm for integrating SIRI into GU risk assessment.Future multicenter studies incorporating Helicobacter pylori infection,non-steroidal antiinflammatory drug exposure,and prospective design are essential to validate and translate these findings into clinical practice. 展开更多
关键词 Gastric ulcer Peptic ulcer disease Systemic inflammatory response index Neutrophil-to-lymphocyte ratio INFLAMMATION Biomarkers
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Evaluation of retina and choroid via OCT in anti-DFS70/LEDGF positive healthy individuals
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作者 Ata Baytaroğlu Suzan Doğruya I.Merve Uçar Baytaroğlu 《International Journal of Ophthalmology(English edition)》 2026年第3期532-538,共7页
AIM:To investigate the association between anti-DFS70 antibody positivity and ocular parameters,specifically,the choroidal vascularity index(CVI)and other optical coherence tomography(OCT)metrics,in a healthy populati... AIM:To investigate the association between anti-DFS70 antibody positivity and ocular parameters,specifically,the choroidal vascularity index(CVI)and other optical coherence tomography(OCT)metrics,in a healthy population.METHODS:This age-and sex-matched case-control study enrolled 84 healthy individuals with positive anti-DFS70 antibody findings and 84 healthy negative controls.All participants underwent detailed ophthalmological examinations,including biometry and OCT imaging.Anti-DFS70 positivity was determined by indirect immunofluorescence and scored semi-quantitatively(1+to 3+).CVI was calculated from OCT images using a standardized protocol with Image J software.Statistical analyses,including Student’s t-test,Mann-Whitney U test,Spearman correlation,and logistic regression,were used to compare groups and identify predictive factors.RESULTS:The individuals who tested positive and negative for anti-DFS70 included in the study were matched for age(median age=47y)and sex(F:M=7:1).CVI was significantly lower in the anti-DFS70-positive group compared to the negative group.A higher anti-DFS70 antibody titer was significantly associated with decreased subfoveal and nasal choroidal thickness(P=0.016 and P=0.014,respectively).In univariate regression analysis,CVI was the only significant predictor of anti-DFS70 positivity[odds ratio(OR)=0.02,P=0.025].Multivariate analysis revealed a positive correlation between macular thinning outside the subfoveal area and anti-DFS70 status(P<0.05).CONCLUSION:Our study demonstrates a novel association between anti-DFS70 antibody positivity and reduced choroidal vascularity in healthy individuals.These findings suggest that anti-DFS70 antibodies may be associated with subtle choroidal vascular changes detectable by OCT,even in asymptomatic individuals.Further longitudinal research is warranted to clarify the underlying mechanisms and long-term clinical significance of these ocular changes. 展开更多
关键词 anti-DFS70 antibodies choroidal vascularity index optical coherence tomography AUTOIMMUNITY
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Nonlinear response of China’s eco-geographical arid/humid regions to climate change during 1961–2020
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作者 YIN Mijia YIN Yunhe +2 位作者 DENG Haoyu WU Shaohong ZHENG Du 《Journal of Geographical Sciences》 2026年第3期535-549,共15页
Climate change significantly affects the arid/humid processes and patterns in China,directly impacting management decisions related to adaptive agriculture and water resources management,desertification control,and sp... Climate change significantly affects the arid/humid processes and patterns in China,directly impacting management decisions related to adaptive agriculture and water resources management,desertification control,and spatial ecological restoration.However,current studies primarily focus on changes in arid/humid climate variables,lacking quantitative characterization of the dynamic evolution of areal systems and their nonlinear responses.Based on the data of national meteorological stations from 1961 to 2020,we systematically quantified the nonlinear response of arid/humid patterns to climate change.The results revealed that 6.98%of eco-geographical arid/humid regions underwent type shifts over the past six decades,with 4.95%transitioning toward wetter conditions.Humid and semi-arid regions expanded significantly while sub-humid and arid regions contracted significantly.In the late 1990s,trends of the humid and sub-humid region shifted.Humid region contraction in northern China was driven primarily by precipitation decline,whereas the Tibetan Plateau responded to increasing potential evapotranspiration.During the same period,the retreat rate of the arid region slowed,linked to intensified aridification in the west part of northern China and a decelerating wetting trend in northwest China,both primarily driven by precipitation trends.Our study reveals the nonlinear response of the arid/humid patterns under climate change,providing a scientific basis for the improvement of regional climate resilience. 展开更多
关键词 ECOGEOGRAPHY arid/humid regions aridity index climate change regional pattern dynamics
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