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A Closed-Form Formulation for the Build-Up Factor and Absorbed Energy for Photons and Electrons in the Compton Energy Range in Cartesian Geometry
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作者 Volnei Borges Julio Cesar Fernandes +2 位作者 Bardo Ernest Bodmann Marco Túllio Vilhena Bárbara Rodriguez 《World Journal of Nuclear Science and Technology》 2012年第1期23-28,共6页
In this work, we report on a closed-form formulation for the build-up factor and absorbed energy, in one and two di- mensional Cartesian geometry for photons and electrons, in the Compton energy range. For the one-dim... In this work, we report on a closed-form formulation for the build-up factor and absorbed energy, in one and two di- mensional Cartesian geometry for photons and electrons, in the Compton energy range. For the one-dimensional case we use the LTSN method, assuming the Klein-Nishina scattering kernel for the determination of the angular radiation intensity for photons. We apply the two-dimensional LTSN nodal solution for the averaged angular radiation evaluation for the two-dimensional case, using the Klein-Nishina kernel for photons and the Compton kernel for electrons. From the angular radiation intensity we construct a closed-form solution for the build-up factor and evaluate the absorbed energy. We present numerical simulations and comparisons against results from the literature. 展开更多
关键词 build-up factor COMPTON Energy CARTESIAN GEOMETRY Fokker-Plank Equation
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On the Build-Up Factor from the Multi-Group Neutron Diffusion Equation with Cylindrical Symmetry
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作者 Julio Cesar Lombaldo Fernandes Marco Túllio Vilhena +1 位作者 Bardo Ernst Bodmann Volnei Borges 《World Journal of Nuclear Science and Technology》 2013年第1期1-5,共5页
We consider the time dependent neutron diffusion equation for one energy group in cylinder coordinates, assuming translational symmetry along the cylinder axis. This problem for a specific energy group is solved analy... We consider the time dependent neutron diffusion equation for one energy group in cylinder coordinates, assuming translational symmetry along the cylinder axis. This problem for a specific energy group is solved analytically applying the Hankel transform in the radial coordinate r. Our special interest rests in the build-up factor for a time dependent linear neutron source aligned with the cylinder axis, which in the limit of zero decay constant reproduces also the static case. The new approach to solve the diffusion equation by integral transform technique is presented and results for several parameter sets and truncation in the solution for the flux and build-up factor are shown and found to be compatible to those of literature [1,2]. 展开更多
关键词 build-up factor CYLINDRICAL GEOMETRY HANKEL TRANSFORM
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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External risk factors for smartphone addiction in adolescents:A systematic literature review
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作者 Wanqing Lin Mohd Azrin Mohd Nasir Suzila Binti Ismail 《Journal of Psychology in Africa》 2026年第1期143-152,共10页
This systematic review synthesizes empirical research on external risk factors for adolescent smartphone addiction.Scopus and Web of Science were searched for English peer-reviewed empirical articles from 2008 onward;... This systematic review synthesizes empirical research on external risk factors for adolescent smartphone addiction.Scopus and Web of Science were searched for English peer-reviewed empirical articles from 2008 onward;28 met inclusion criteria(excluding non-adolescents,generic internet addiction,non-empirical work,or non-English).Thematic synthesis organized findings into three external risk domains—family,school,and peers—considering cultural/contextual mechanisms.Family dynamics(parental phubbing,harsh parenting,dysfunction),school stressors,and adverse peer relationships were identified as accumulating,direct and indirect contributors to smartphone addiction.These operate within a techno-ecological framework,where digital technologies amplify vulnerabilities and create new pathways for maladaptive use.Evidence favors an ecological,multi-level perspective.Future research should use longitudinal designs,standardize measures across cultures,and examine understudied regions—especially Africa—to guide culturally sensitive interventions. 展开更多
关键词 Smartphone addiction ADOLESCENT family risk factor school risk factor peer risk factor
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Risk factors and early identification markers for post-ischemic stroke anxiety and depression
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作者 Jie-Dong Zhao Song-Wang Qiu +2 位作者 Kai-Yan Lin Hui-Yan Lin Chang-Wei Yu 《World Journal of Psychiatry》 2026年第1期201-211,共11页
BACKGROUND Ischemic stroke is one of the leading global causes of disability and death.Despite advances in modern medical technology that improve acute treatment and rehabilitation measures,post-stroke anxiety and dep... BACKGROUND Ischemic stroke is one of the leading global causes of disability and death.Despite advances in modern medical technology that improve acute treatment and rehabilitation measures,post-stroke anxiety and depression(PSD)do not receive sufficient attention.AIM To systematically evaluate risk factors and early identification markers for PSD for more precise screening and intervention strategies in clinical practice.METHODS This retrospective study analyzed clinical data from 112 patients with ischemic stroke admitted between January 2022 and December 2024.Based on assessments using the Hamilton Rating Scale for Anxiety(HAMA)and Hamilton Rating Scale for Depression(HAMD)at 2 weeks(±3 days)post-stroke,patients were classified into the PSD group(HAMA≥7 and/or HAMD≥7)and the non-PSD group(HAMA<7 and HAMD<7).Observation indicators included psychological assessment,demographic and clinical characteristics,stroke-related clinical indicators,neuroimaging assessments,and laboratory biomarkers.Multivariate logistic regression analysis was used to identify independent risk factors for PSD,and receiver operating characteristic curve analysis was used to evaluate the diagnostic value of potential biomarkers.RESULTS Of the 112 patients,46(41.1%)were diagnosed with PSD.Multivariate analysis identified five independent risk factors:Female gender[Odds ratio(OR)=2.32,95%confidence interval(CI):1.56-3.45],history of mental disorders prior to stroke(OR=3.17,95%CI:1.89-5.32),infarct location in the frontal lobe or limbic system(OR=2.86,95%CI:1.73-4.71),stroke severity with National Institutes of Health Stroke Scale≥8 at admission(OR=2.54,95%CI:1.62-3.99),and low social support(Social Support Rating Scale<35,OR=2.18,95%CI:1.42-3.36).Subgroup analysis showed that depression patients more commonly had left hemisphere lesions(68.4%vs 45.2%),while anxiety patients more frequently presented with right hemisphere lesions(59.5%vs 39.5%).The PSD group exhibited larger infarct volumes(8.7 cm^(3) vs 5.3 cm^(3)),more severe white matter hyperintensities,and more pronounced frontal lobe atrophy.Analysis of inflammatory markers showed significantly elevated levels of interleukin-6(7.8 pg/mL vs 4.5 pg/mL)and tumor necrosis factor-alpha(15.6 pg/mL vs 9.8 pg/mL)in the PSD group,while hypothalamicpituitary-adrenal axis function assessment revealed higher cortisol levels(386.5±92.3 nmol/L vs 328.7±75.6 nmol/L)and flattened diurnal rhythm in the PSD group.CONCLUSION PSD is a complex neuropsychiatric consequence of stroke involving disruption of the frontal-limbic circuitry,neuroinflammatory responses,and dysfunction of the hypothalamic-pituitary-adrenal axis. 展开更多
关键词 Ischemic stroke Anxiety and depression Risk factors Biomarkers Brain-derived neurotrophic factor
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Organelle symphony:Nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in stroke pathobiology
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作者 Ziliang Hu Mingyue Zhao +4 位作者 Hangyu Shen Liangzhe Wei Jie Sun Xiang Gao Yi Huang 《Neural Regeneration Research》 2026年第4期1483-1496,共14页
Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is cha... Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is characterized by bleeding within the brain.Stroke is a lifethreatening cerebrovascular condition characterized by intricate pathophysiological mechanisms,including oxidative stress,inflammation,mitochondrial dysfunction,and neuronal injury.Critical transcription factors,such as nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B,play central roles in the progression of stroke.Nuclear factor erythroid 2-related factor 2 is sensitive to changes in the cellular redox status and is crucial in protecting cells against oxidative damage,inflammatory responses,and cytotoxic agents.It plays a significant role in post-stroke neuroprotection and repair by influencing mitochondrial function,endoplasmic reticulum stress,and lysosomal activity and regulating metabolic pathways and cytokine expression.Conversely,nuclear factor-kappa B is closely associated with mitochondrial dysfunction,the generation of reactive oxygen species,oxidative stress exacerbation,and inflammation.Nuclear factor-kappa B contributes to neuronal injury,apoptosis,and immune responses following stroke by modulating cell adhesion molecules and inflammatory mediators.The interplay between these pathways,potentially involving crosstalk among various organelles,significantly influences stroke pathophysiology.Advancements in single-cell sequencing and spatial transcriptomics have greatly improved our understanding of stroke pathogenesis and offer new opportunities for the development of targeted,individualized,cell typespecific treatments.In this review,we discuss the mechanisms underlying the involvement of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in both ischemic and hemorrhagic stroke,with an emphasis on their roles in oxidative stress,inflammation,and neuroprotection. 展开更多
关键词 inflammation nuclear factor erythroid 2-related factor 2 nuclear factor-kappa B ORGANELLES oxidative stress STROKE
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Prevalence and factors associated with acute pain among emergency trauma patients
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作者 Elias Alemayehu Worku Habtu Adane Aytolign +1 位作者 Zemenay Ayinie Mekonnen Endale Gebreegziabher Gebremedhn 《World Journal of Emergency Medicine》 2026年第1期36-42,共7页
BACKGROUND:Acute pain is a sudden experience secondary to injuries and varies in perception among individuals.In trauma patients,it can negatively aff ect respiratory function,immune response,and wound healing,making ... BACKGROUND:Acute pain is a sudden experience secondary to injuries and varies in perception among individuals.In trauma patients,it can negatively aff ect respiratory function,immune response,and wound healing,making it a signifi cant public health concern.This study is to determine the prevalence and factors associated with acute pain among emergency trauma patients.METHODS:A multicenter cross-sectional study was conducted.Data were collected via interviewer-administered questionnaires and patient chart review.The data were analyzed via the statistical package for social science version 25.Bivariable and multivariable logistic regression analyses were used.Variables with a P-value<0.05 were considered statistically signifi cant.RESULTS:A total of 397 patients were included in the study,for a response rate of 96.8%.The prevalence of pain during admission was 91.9%(95%confi dence intervals[95%CIs]:88.8%-94.4%).Blunt trauma(adjusted odds ratio[aOR]=2.82;95%CI:1.23-6.45),analgesia before admission to the emergency department(aOR=2.71;95%CI:1.16-6.36),documentation of pain severity in the chart(aOR=2.71;95%CI:1.16-6.36),analgesia provided within two hours after admission(aOR=7.60;95%CI:2.79-20.68),use of non-pharmacological pain management methods(aOR=3.09;95%CI:1.35-7.08)and availability of analgesia(aOR=3.95;95%CI:1.36-11.43)were associated with acute pain experience.CONCLUSION:The prevalence of acute pain among emergency trauma patients was high in the study area.Analgesia should be administered prior to admission,and non-pharmacological pain management should be implemented.Moreover,training on pain assessment and management should be provided for healthcare providers in the emergency department. 展开更多
关键词 Acute pain EMERGENCY TRAUMA factor
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Techniques and factors for reducing chronic neuropathic pain: A review
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作者 Damien P.Kuffler 《Neural Regeneration Research》 2026年第4期1353-1358,共6页
Nerve trauma commonly results in chronic neuropathic pain. This is by triggering the release of proinflammatory mediators from local and invading cells that induce inflammation and nociceptive neuron hyperexcitability... Nerve trauma commonly results in chronic neuropathic pain. This is by triggering the release of proinflammatory mediators from local and invading cells that induce inflammation and nociceptive neuron hyperexcitability. Even without apparent inflammation, injury sites are associated with increased inflammatory markers. This review focuses on how it might be possible to reduce neuropathic pain by reducing inflammation. Physiologically, pain is resolved by a combination of the out-migration of pro-inflammatory cells from the injury site, the down-regulation of the genes underlying the inflammation, up-regulating genes for anti-inflammatory mediators, and reducing nociceptive neuron hyperexcitability. While various techniques reduce chronic neuropathic pain, the best are effective on < 50% of patients, no technique reliably or permanently eliminates neuropathic pain. This is because most techniques are predominantly aimed at reducing pain, not inflammation. In addition, while single factors reduce pain, increasing evidence indicates significant and longer-lasting pain relief requires multiple factors acting simultaneously. Therefore, it is not surprising that extensive data indicate that the application of platelet-rich plasma provides more significant and longer-lasting pain suppression than other techniques, although its analgesia is neither complete nor permanent. However, several case reports indicate that platelet-rich plasma can induce permanent neuropathic pain elimination when the platelet concentration is significantly increased and is applied to longer nerve lengths. This review examines the primary triggers of the development and maintenance of neuropathic pain and techniques that reduce chronic neuropathic pain. The application of plateletrich plasma holds great promise for providing complete and permanent chronic neuropathic pain elimination. 展开更多
关键词 anti-inflammatory factors axon regeneration inflammatory pain nerve regeneration nerve repair pain elimination pain reduction platelet-rich plasma pro-inflammatory factors restoration of function
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Incidence,risk factors and survival outcomes of post-transplant tertiary hyperparathyroidism in kidney recipients
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作者 Shmuel Hanson Jorge Menendez Lorenzo +3 位作者 Chukwuma Austin Chukwu Anirudh Rao Rachel Middleton Philip A Kalra 《World Journal of Transplantation》 2026年第1期153-166,共14页
BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite imp... BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite improved renal function.It is potentially associated with an increased risk of cardiovascular events,renal osteodystrophy,pathologic fractures,graft loss,and mortality.AIM To evaluate the incidence,risk factors,and outcomes of PT-tHPT amongst kidney transplant recipients.METHODS A total of 887 transplant recipients who underwent transplantation between 2000 and 2020 were evaluated.Univariable and multivariable logistic regression was performed to determine the predictors of tertiary hyperparathyroidism.Graft and recipient outcomes were assessed using multivariable Cox regression.A separate multivariable Cox regression was performed to determine the effect of treatment strategies on outcomes.RESULTS PT-tHPT,defined as elevated PTH(>65 ng/L)and persistent hypercalcemia(>2.60 mmol/L),was diagnosed in 14%of recipients.Risk factors for PT-tHPT included older age[odds ratio(OR)=1.36,P<0.001],Asian ethnicity(OR=0.33,P=0.006),total ischemia time(OR=1.03,P=0.048 per hour),pre-transplant serum calcium(OR=1.38,P<0.001)per decile increase,pre-transplant PTH level(OR=1.31,P<0.001)per decile increase,longer dialysis duration(OR=1.12,P=0.002)per year,history of acute rejection(OR=2.37,P=0.012),and slope of estimated glomerular filtration rate change(OR=0.91,P=0.001).There were a 3.4-fold higher risk of death-censored graft loss and a 1.9-fold greater risk of recipient death with PT-tHPT.The three treatment strategies of conservative management,calcimimetic and parathyroidectomy did not significantly change the graft or patient outcome.CONCLUSION Pretransplant elevated calcium and PTH levels,older age and dialysis duration are associated with PT-tHPT.While PT-tHPT significantly affects graft and recipient survival,the treatment strategies did not affect survival. 展开更多
关键词 Post-transplant tertiary hyperparathyroidism Kidney transplantation Parathyroid hormone PARATHYROIDECTOMY Calcimimetics Graft survival Risk factors Mineral bone disorder Fibroblast growth factor 23 Treatment outcomes
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An observational longitudinal cohort study on the trajectory of intrinsic capacity and its influencing factors among older Chinese adults:a growth mixture model analysis
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作者 Xue Liu Yurun Cai +4 位作者 Huimin Wen Huan Fan Weiyao Li Yilin Cheng Shuqin Xiao 《Nursing Communications》 2026年第3期1-13,共13页
Background:The trajectory of intrinsic capacity(IC)among the older population is characterized by its diversity and is predictive of adverse health outcomes such as disability,nursing home admission,decline in quality... Background:The trajectory of intrinsic capacity(IC)among the older population is characterized by its diversity and is predictive of adverse health outcomes such as disability,nursing home admission,decline in quality of life,and mortality.Gaining an understanding of the trajectory of IC and the factors that influence it is of paramount importance for fostering healthy aging.This research is focused on exploring the trajectory of IC among older adults in China and examining the factors that influence it.Methods:This observational longitudinal cohort study leveraged data from the China Health and Retirement Longitudinal Study(CHARLS),which was conducted in the years 2011,2013,and 2015.For the purpose of this analysis,a total of 2,233 participants who were aged 60 and over were included.A Growth Mixture Model(GMM)was utilized to define trajectory categories for IC.Influential factors were ascertained based on the health ecology model,and binary logistic regression analysis was utilized to investigate the factors linked with the different trajectory categories.Results:Two distinct trajectory classes of IC were identified:Class 1,the normal-stable group,encompassed 90.4%of the elderly population,while Class 2,the declining group,made up 9.6%.Advanced age and a history of stroke were found to be significantly associated with Class 2.High scores in activities of daily living(ADL),employment status,receiving primary or junior high school education,and residence in the East or Central regions of China were significantly linked with Class 1.Conclusion:The trajectory of IC among older Chinese adults is marked by its heterogeneity.Advanced age and a history of stroke are significant risk factors for a declining IC trajectory,while higher ADL scores,being employed,receiving primary or junior high school education,and residing in the East or Central regions of China are protective factors associated with a stable IC trajectory.Healthcare institutions must closely monitor IC levels and understand these trajectory patterns to implement personalized and targeted interventions promptly to maintain IC at a healthy level and advocate for healthy aging. 展开更多
关键词 intrinsic capacity trajectory development influencing factors
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Environmental factors at different scales:a review of their effects on spontaneous fermentation Chinese Baijiu and related mechanisms
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作者 Lei Yuan Jieqi Mao +6 位作者 Feng Lin Caihong Shen Dongna Ma Shuangping Liu Mingliang Li Miao Liu Jian Mao 《Food Science and Human Wellness》 2026年第2期560-572,共13页
Environment serves as the pivotal medium to produce fermented food,with fluctuations in environmental factors exerting a profound impact on the modulation of fermentation microbial communities.Such shifts are crucial ... Environment serves as the pivotal medium to produce fermented food,with fluctuations in environmental factors exerting a profound impact on the modulation of fermentation microbial communities.Such shifts are crucial for the distinctiveness of fermented food flavor and the variability in quality.Chinese liquor(Baijiu)is one of the typical representatives of spontaneous fermented food.In this review,the multifaceted relationship between regional environmental attributes and the fermentation dynamics of Baijiu was examined,with a spotlight on the strong-flavor,sauce-flavor,and light-flavor varieties.It reveals the influence of regional environmental factors and brewing environmental factors on microbial function and metabolism,which results in the formation of unique flavor characteristics of Baijiu.The 9 main factors affecting the microecology of Baijiu fermentation were further explored,including environmental sensitivity,microbial interactions,biogeographic patterns,and key abiotic factors such as temperature and humidity.Environmental factor management is crucial for controlling microbial community in fermentation.Intelligent detection of the fermentation system is combined with artificial intelligence to realize the digitalization of Baijiu fermentation,with a view to further studying the environmental mechanism or quantitative control relationship of natural fermentation,improving the environmental stability of natural fermentation,and promoting the mechanization and intelligence of fermentation production. 展开更多
关键词 Environmental factors Spontaneous fermentation Chinese Baijiu MICROORGANISM MICROECOLOGY
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Hydrochemical characteristics,evolution,and controlling factors of a karstic river with reservoirs:Insights from spatial-temporal analysis
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作者 Jiang Wu Ting Wang +4 位作者 Tang Liu Jia-Ju Liu Nan Xu Hui Zeng Ling-Yan He 《Journal of Environmental Sciences》 2026年第1期108-119,共12页
Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-me... Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-ments in karst hydrology,significant gaps remain in long-term trends,underlying processes,and quantitative effects of environmental changes.This is especially true in areas like the Wujiang River(WJ)in China,where human activities such as reservoir construction and land use/cover changes have accelerated hydrochemical changes.We combined recent and historical monitoring data to provide a detailed analysis of the spatial and temporal characteristics,evolution,and controlling factors of major ions in WJ.These findings are important for local water management and contribute to global efforts to manage similar karst systems facing human-induced pressures.Our research shows clear seasonal differences in solute concentrations,with higher levels during the dry season.WJ’s water is rich in calcium,with Ca-HCO_(3) ion pairs being the most common.Reservoir monitor-ing stations show much higher levels of NO_(3)^(−)and SO_(4)^(2−)compared to river-type stations,likely due to longer hydraulic retention time and increased acid deposition.The study confirms the significant role of pH and water temperature in rock weathering processes.Land use/cover changes were identified as the primary drivers of solute variations(46.37%),followed by lithology(13.92%)and temperature(8.35%).Over the past two decades,in-tense carbonate weathering has been observed,especially during wet seasons.Among karstic provinces,Guizhou Province stands out with the highest ion concentrations,indicative of its extensive karst coverage and heightened weathering processes. 展开更多
关键词 Wujiang river Karst Reservoir Major ion Controlling factor
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Landslide susceptibility on the Qinghai-Tibet Plateau:Key driving factors identified through machine learning
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作者 YANG Wanqing GE Quansheng +3 位作者 TAO Zexing XU Duanyang WANG Yuan HAO Zhixin 《Journal of Geographical Sciences》 2026年第1期199-218,共20页
Landslides pose a formidable natural hazard across the Qinghai-Tibet Plateau(QTP),endangering both ecosystems and human life.Identifying the driving factors behind landslides and accurately assessing susceptibility ar... Landslides pose a formidable natural hazard across the Qinghai-Tibet Plateau(QTP),endangering both ecosystems and human life.Identifying the driving factors behind landslides and accurately assessing susceptibility are key to mitigating disaster risk.This study integrated multi-source historical landslide data with 15 predictive factors and used several machine learning models—Random Forest(RF),Gradient Boosting Regression Trees(GBRT),Extreme Gradient Boosting(XGBoost),and Categorical Boosting(CatBoost)—to generate susceptibility maps.The Shapley additive explanation(SHAP)method was applied to quantify factor importance and explore their nonlinear effects.The results showed that:(1)CatBoost was the best-performing model(CA=0.938,AUC=0.980)in assessing landslide susceptibility,with altitude emerging as the most significant factor,followed by distance to roads and earthquake sites,precipitation,and slope;(2)the SHAP method revealed critical nonlinear thresholds,demonstrating that historical landslides were concentrated at mid-altitudes(1400-4000 m)and decreased markedly above 4000 m,with a parallel reduction in probability beyond 700 m from roads;and(3)landslide-prone areas,comprising 13%of the QTP,were concentrated in the southeastern and northeastern parts of the plateau.By integrating machine learning and SHAP analysis,this study revealed landslide hazard-prone areas and their driving factors,providing insights to support disaster management strategies and sustainable regional planning. 展开更多
关键词 landslide susceptibility machine learning SHAP driving factors nonlinear effects
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Lagged effects of risk factors on the disability of older adults:A distributed lag non-linear model approach
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作者 Yitong Mao Zhiting Guo +2 位作者 Wen Gao Yuping Zhang Jingfen Jin 《International Journal of Nursing Sciences》 2026年第1期53-60,I0004,I0005,共10页
Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and ... Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and Retirement Longitudinal Study(CHARLS).After feature selection via Elastic Net Regularization,we applied DLNMs to evaluate the lagged effects of risk factors.Disability was defined as the presence of any difficulties in basic activities of daily living(BADL).The cumulative relative risk(CRR)was calculated by summing the lag-specific risk estimates,representing the cumulative disability risk over the specified lag period.Effect modifications and sensitivity analyses were also performed.Results This study included a total of 2,318 participants.Early-phase lag factors,such as the difficulty in stooping(CRR=3.58;95%CI:2.31-5.55;P<0.001)and walking(CRR=2.77;95%CI:1.39-5.55;P<0.001),exerted the strongest effects immediately upon occurrence.Mid-phase lag factors,such as arthritis(CRR=1.51;95%CI:1.10-2.06;P=0.001),showed a resurgence in disability risk within 2-3 years.Late-phase lag factors,including depressive symptoms(CRR=2.38;95%CI:1.30-4.35;P<0.001)and elevated systolic blood pressure(CRR=1.64;95%CI:1.06-2.79;P=0.02),exhibited significant long-term cumulative risks.Conversely,grip strength(CRR=0.80;95%CI:0.54-0.95;P=0.02)and social participation(CRR=0.89;95%CI:0.73-0.99;P=0.04)were significant protective factors.Conclusions The findings underscore the importance of tailored interventions that account for various lag characteristics of different factors to effectively mitigate disability risk.Future studies should explore the underlying biological and sociological mechanisms of these lagged effects,identify intervention strategies that target risk factors with different lagged patterns,and evaluate their effectiveness. 展开更多
关键词 Ageing DISABILITY Distributed lag non-linear models Nusing Risk factors
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Effect of Acupuncture at Points of the Bladder Meridian of Foot-Taiyang on Serum Inflammatory Factors in Rabbit Models of Cervical Spondylosis
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作者 Wenrong Yang Shu Zhao +3 位作者 Jincai Liu Dan Wang Zhijun Chen Zhigang Zhao 《Journal of Clinical and Nursing Research》 2026年第1期1-12,共12页
Objective:Based on the theory of“Taiyang governs tendons”,to explore the effect of acupuncture at points of the Bladder Meridian of Foot-Taiyang on the expression of serum inflammatory factors in rabbit models of ce... Objective:Based on the theory of“Taiyang governs tendons”,to explore the effect of acupuncture at points of the Bladder Meridian of Foot-Taiyang on the expression of serum inflammatory factors in rabbit models of cervical spondylosis.Methods:Thirty New Zealand white rabbits were randomly divided into a blank group,a model group,and a treatment group,with 10 rabbits in each group.The models of cervical spondylosis in the model group and treatment group were established by long-term head-down flexion combined with cold-damp stimulation.After modeling,the treatment group received acupuncture at three points(Kunlun,Weizhong,and Feishu)on the Bladder Meridian of Foot-Taiyang,once a day for 20 minutes each time,for 14 consecutive days;the model group and blank group received no therapeutic intervention.After the intervention,cardiac blood was collected from all rabbits to detect the expression levels of serum inflammatory factors IL-6,TNF-α,and IL-1β.Meanwhile,cervical muscle tissue was collected,stained with HE,and the morphological changes of the posterior cervical muscle tissue in each group were observed under an optical microscope.Results:After modeling,the levels of inflammatory factors in the serum of rabbits in the model group and treatment group were significantly increased compared with those before modeling,with a statistically significant difference(p<0.01).After intervention,the serum inflammatory factors in the treatment group decreased significantly compared with those in the model group,and the difference was statistically significant(p<0.01).Conclusion:Acupuncture at points of the Bladder Meridian of Foot-Taiyang in rabbit models of cervical spondylosis can reduce the serum levels of inflammatory factors TNF-α,IL-1β,and IL-6. 展开更多
关键词 Cervical spondylosis Bladder meridian of foot-Taiyang ACUPUNCTURE Inflammatory factors
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Integrative Analysis of Genetic-Ecological Factors Shaping Epimedium Chemical Diversity
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作者 Ziying Huang Ruikang Ma +6 位作者 Anning Li Yufei Cheng Xiaolin Lin Mengzhi Li Yu Zhang Liping Shi Linlin Dong 《Phyton-International Journal of Experimental Botany》 2026年第1期132-150,共19页
Epimedium is commonly used to treat bone injury and kidney disease,with prenylated flavonol glycosides(PFGs)as its active ingredients.It has attracted much attention due to prominent healthcare and therapeutic effects... Epimedium is commonly used to treat bone injury and kidney disease,with prenylated flavonol glycosides(PFGs)as its active ingredients.It has attracted much attention due to prominent healthcare and therapeutic effects,but faces problems of adulteration with closely related species and confusion about geographical origins.In this study,multiple technical approaches were employed to identify its genetic characteristics and metabolic differences.Based on DNA barcoding,20 batches of samples were analyzed.The genetic distances of matK,ITS and psbA-trnH within species were all smaller than those between species,and psbA-trnH along with ITS+psbA-trnH proved most effective in distinguishing botanical sources.With Inter-simple sequence repeat(ISSR)technology,12 highly polymorphic and reproducible primers were selected from 21,and 189 alleles were detected.Epimedium sagittatum showed distinct genetic diversity.Samples with similar genetic distance and geographical location also tended to cluster together.Eight index components were analyzed,and their contents showed significant differences.The total content ranged from 0.50%to 7.09%,and icariin and epimedin C were identified as potential biomarkers.Integrative analysis revealed that the differences in index components were jointly driven by genetic diversity and ecological factors.Additionally,“mean temperature of driest quarter”,“precipitation seasonality”,and“temperature annual range”were identified as key environmental factors.This study provides a reliable experimental basis for the authenticity and quality evaluation of Epimedium. 展开更多
关键词 EPIMEDIUM DNA barcoding ISSR marker FINGERPRINT active ingredients environmental factor
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Analysis of Histochemical Localization and Content Influencing Factors of Saponins in Pseudostellaria heterophylla
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作者 Huiqing PAN Yanda ZHANG +3 位作者 Zhenhua WANG Qi ZHAO Zuyun YE Xin WANG 《Medicinal Plant》 2026年第1期5-9,19,共6页
This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides... This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides an in-depth analysis and summary of the effects of biological factors,environmental conditions,agronomic practices,processing methods,and continuous cropping obstacles on the synthesis of P.heterophylla saponins,as well as their underlying mechanisms.Based on identified gaps in the current literature,future research directions and prospects are proposed.The findings of this review offer valuable insights for advancing the understanding of the saponin biosynthesis mechanisms in P.heterophylla and for enhancing its quality. 展开更多
关键词 Pseudostellaria heterophylla SAPONIN Histochemical localization Content influencing factors Research progress
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Variations and major driving factors for soil nutrients in a typical karst region in Southwest China
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作者 Miaomiao Wang Hongsong Chen +1 位作者 Wei Zhang Kelin Wang 《Journal of Integrative Agriculture》 2026年第2期424-435,共12页
Understanding the spatial distributions and corresponding variation mechanisms of key soil nutrients in fragile karst ecosystems can assist in promoting sustainable development.However,due to the implementation of eco... Understanding the spatial distributions and corresponding variation mechanisms of key soil nutrients in fragile karst ecosystems can assist in promoting sustainable development.However,due to the implementation of ecological restoration initiatives such as land-use conversions,novel changes in the spatial characteristics of soil nutrients remain unknown.To address this gap,we explored nutrient variations and the drivers of the variation in the 0–15 cm topsoil layer using a regional-scale sampling method in a typical karst area in northwest Guangxi Zhuang Autonomous Region,Southwest China.Descriptive statistics,geostatistics,and spatial analysis were used to assess the soil nutrient variability.The results indicated that soil organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),and total potassium(TK)concentrations showed moderate variations,with coefficients of variance being 0.60,0.60,0.71,and 0.72,respectively.Moreover,they demonstrated positive spatial autocorrelations,with global Moran's indices being 0.68,0.77,0.64,and 0.68,respectively.However,local Moran's index values were low,indicating large spatial variations in soil nutrients.The best-fitting semi-variogram models for SOC,TN,TP,and TK concentrations were spherical,Gaussian,exponential,and exponential,respectively.According to the classification criteria of the Second National Soil Census in China,SOC and TN concentrations were relatively sufficient,with the proportions of rich and very rich levels being up to 90.9 and 96.0%,respectively.TP concentration was in the mediumdeficient level,with the areas of medium and deficient levels accounting for 33.7 and 30.1%of the total,respectively.TK concentration was deficient,with the cumulative area of extremely deficient,very deficient,and deficient levels accounting for 87.6%of the total area.Consequently,the terrestrial ecosystems in the study area were more vulnerable to soil P and K than soil N deficiencies.Furthermore,variance partitioning analysis of the influencing factors showed that,except for the interactions,the single effect of other soil properties accounted more for soil nutrient variations than spatial and environmental variables.These results will aid in the future management of terrestrial ecosystems. 展开更多
关键词 dominant factor GEOSTATISTICS karst ecosystem soil nutrient classification spatial variation
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Factors associated with aseptic loosening after primary total hip arthroplasty:A systematic review and meta-analysis
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作者 Guo-Qing Li Ji Zhang Yong Huang 《World Journal of Orthopedics》 2026年第1期149-163,共15页
BACKGROUND Aseptic loosening remains the leading cause of revision in primary total hip arthroplasty(pTHA).However,the literature demonstrates significant variability regarding the relative contributions of different ... BACKGROUND Aseptic loosening remains the leading cause of revision in primary total hip arthroplasty(pTHA).However,the literature demonstrates significant variability regarding the relative contributions of different factors.AIM To investigate the key determinants of aseptic loosening,we performed a systematic review and meta-analysis.METHODS A comprehensive search of PubMed,Web of Science,EMBASE,and the Cochrane Library was conducted,encompassing studies from database inception to January 1,2025.Meta-analyses were performed to evaluate factors associated with aseptic loosening following pTHA.Inclusion and exclusion criteria were systematically applied at each stage to ensure methodological transparency and reproducibility.Study quality was assessed using standardized categories.Pooled odds ratio(OR)with corresponding 95%confidence interval were calculated with random-or fixed-effects models to generate reliability estimates,and study heterogeneity was visualized using forest plots.Ten factors,categorized into patient-,surgeon-,and device-related domains,were reviewed and meta-analyzed.Funnel plot analysis demonstrated a relatively symmetrical distribution,suggesting minimal publication bias.RESULTS A meta-analysis of 20 studies(520789 participants)found a pooled prevalence of 1.96%.Significant risk factors for aseptic loosening after pTHA included elevated body mass index(OR=1.116,P<0.001),higher Charlson comorbidity index(OR=1.378,P<0.001),prosthesis-related factors(OR=1.497,P<0.001),and adverse lifestyles(OR=2.198,P=0.037).Protective factors were non-white race(OR=0.445,P<0.001)and favorable genetics(OR=0.723,P<0.001).Male sex increased risk(OR=1.232,P=0.016),while age and anatomy were not significant.Surgical expertise showed a slight protective effect(OR=1.048,P<0.001).A comprehensive understanding of the modifiable and non-modifiable factors contributing to aseptic loosening after pTHA requires consideration of patient-related factors,surgical expertise,and prosthesis characteristics.CONCLUSION The identification of these factors is critical for risk mitigation.High-risk patients should receive targeted counseling regarding individualized profiles.Further studies are warranted to establish clearer causal relationships and identify additional contributing factors. 展开更多
关键词 factorS Aseptic loosening Primary total hip arthroplasty Systematic review META-ANALYSIS
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Recent advances on micro-polluted water remediation by full-scale constructed wetlands:Pollutant removal performance,key influencing factors,and enhancing strategies
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作者 Qiang Ning Peihao Yan +4 位作者 Lingyan Zhao Zhiyi Lin Jian Zhang Zizhang Guo Haiming Wu 《Journal of Environmental Sciences》 2026年第1期565-576,共12页
The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-ni... The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-nition as an eco-friendly solution for removing pollutants from various wastewater sources and are increasingly applied for micro-polluted water treatment.By reviewing 78 full-scale CW studies from Web of Science,it is summarized that the ranges of ammonium nitrogen(NH4+-N)concentrations in runoff,wastewater treatment plant effluent and polluted river were 0.1–6.6,0.3–12.3,and 0.2–41.1 mg/L,respectively.The ranges of ni-trate nitrogen concentrations were 0.2–14.2,0–5.7,and 0–2.6 mg/L,respectively.Removal efficiencies of CWs for micro-polluted water varied by CW types.The total nitrogen removal efficiencies for subsurface-flow CWs,free-water surface-flow CWs,and hybrid CWs ranged from 27.4%to 66.5%,16.8%to 89.8%,and 19.4%to 88.2%,respectively.The NH4+-N removal efficiencies ranged from 34.2%to 73.6%,38.4%to 89.4%and 13.5%to 94.2%,respectively.Additionally,other factors influencing contaminant removal efficiency such as hydraulic retention time,vegetation types,redox micro-environment and influent water quality were evaluated.Based on these findings,two strategies for improving the purification performance of CWs were proposed:the selection of incorporating electron donor substrates and the optimization of operation parameters.This paper serves as a synthesis of information to guide future research and full-scale CW applications in micro-polluted water treatment. 展开更多
关键词 Constructed wetlands Micro-polluted water Nutrient removal Influencing factors Enhancing strategies
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