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英国A Level考试制度的演进脉络及其对我国高考改革的镜鉴
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作者 温军英 《宁波大学学报(教育科学版)》 2026年第1期122-132,共11页
A Level考试素有“英国高考”之称。其制度演进大致经历了发轫与探索、扩张与调适、回归与重塑三个阶段,其主要变革内容包括四个方面:组织形式从年终末考的线性考试模式发展为一年多考的模块化考试,再回归线性考试模式;考试评价从常模... A Level考试素有“英国高考”之称。其制度演进大致经历了发轫与探索、扩张与调适、回归与重塑三个阶段,其主要变革内容包括四个方面:组织形式从年终末考的线性考试模式发展为一年多考的模块化考试,再回归线性考试模式;考试评价从常模参照转变为标准参照,评价手段逐步优化;考试要求从注重学科深度转变为强调知识广度,再发展为追求广度和深度并重;考试内容从偏重学术性转变为普职并重,再发展为职普融通和强调基础学科。变革的动因既有来自外部的国际竞争加剧和国内政党轮替,也有来自内部的文化价值观驱动和考试选才效度追求。A Level考试制度对我国高考改革有一定启发,我国可结合国情,以基础学科为支点、职普融通为路径、多样化的考试选择为依托、预测效度为导向,开展本土化探索。 展开更多
关键词 A level 高考 考试 选科 高校招生
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Simulating Groundwater Levels Responses to Precipitation and Withdrawal:A Lag-time Deep Learning Model
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作者 LI Shuai ZHU Lin +3 位作者 GAO Lei GONG Huili LI Xiaojuan SU Xiaosi 《Chinese Geographical Science》 2026年第2期351-364,共14页
Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi... Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi-head Self-attention mechan-ism(MSAM-GRU)to simulate GWLs in both confined and unconfined aquifers simultaneously.The model innovatively captures the lag times between GWLs in the unconfined aquifer and precipitation,as well as between GWLs in the confined aquifer and the upper aquifer.We have assessed the effectiveness of the proposed model using a case study in the Beijing Plain,China from January 2005 to December 2020.With the consideration of lag times,the results indicated that the MSAM-GRU model exhibits a maximum 67%and 73%reduction in RMSE compared to the Attention mechanism-GRU(AM-GRU)and GRU model,respectively.MSAM-GRU model exhibited a 31%reduction in RMSE and a 0.12 increase in R^(2) compared to the same model that do not account for lag time.In Region I,the shortest lag time of GWL in the unconfined aquifer was two months,while that in the confined aquifer was three months,indicating a longer delayed response in the confined aquifer.MSAM-GRU model considering lag time,was then applied to simulate the GWLs in the unconfined aquifer under different scenarios and to analyze whether GWL fluctuations affect subway operations.The simulation res-ults showed that under the scenario 1,the GWL in the unconfined aquifer would rise above the depth of subway station floor,threaten-ing the operation of subways.This study can provide reliable technical support for the accurate simulation of GWLs in multi-aquifer systems. 展开更多
关键词 groundwater level(GWL) Multi-head Self-attentionmechanism-Gate Recurrent Unit(MSAM-GRU) PRECIPITATION unconfined aquifer and confined aquifer Beijing Plain China
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英国T-Level行动计划的特色、举措与启示
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作者 杨立力 李建国 《荆楚理工学院学报》 2026年第1期16-23,共8页
英国政府为解决高校培养技能与雇主所需技能不匹配问题,推行了T-Level行动计划。T-Level行动计划依据国家与地方两个层面的数据调查,基于雇主和利益相关者需求,制定技能人才的培养目标、课程规划及技术资格认证,强调通过“工作本位”学... 英国政府为解决高校培养技能与雇主所需技能不匹配问题,推行了T-Level行动计划。T-Level行动计划依据国家与地方两个层面的数据调查,基于雇主和利益相关者需求,制定技能人才的培养目标、课程规划及技术资格认证,强调通过“工作本位”学习培养技能,并通过核心知识测评与职业专项技能考核相结合进行技能评价,在一定程度上提升了社会所需技能人才培养的质量。这为我国职业教育中高质量复合型技能人才的培养带来了三点启示:一是构建利益相关者共建、职普融通的技能培养体系;二是创建围绕“工作本位”的技能培养教学和评价模式;三是建立基于人的全面发展需求的多维技能结构。 展开更多
关键词 T-level行动计划 技术教育改革 工作本位学习 雇主项目考核
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基于Level Set方法的HG-80钢晶粒长大模型的建模与仿真
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作者 刘铭阳 陈学文 +5 位作者 周正 毛怡然 徐栋栋 李强 易浩 周旭东 《材料热处理学报》 北大核心 2025年第6期162-170,共9页
为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模... 为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模型。通过二次开发将计算所得的Burke-Turnbull模型参数导入DIGIMU■软件中,从晶粒尺寸分布、晶粒生长动力学和晶粒拓扑结构等方面,基于Level Set方法建立了描述HG-80钢的晶粒长大模型并通过DIGIMU■软件进行仿真计算。结果表明:随着保温时间的增加,实验钢的晶粒尺寸明显增大,晶粒生长速率逐渐减小,呈抛物线状增长;为了验证Burke-Turnbull模型的准确性,将平均晶粒尺寸的模型预测值与实验值进行对比,相关系数R为0.991,表明该模型的准确性较高;通过Level Set方法仿真计算得出的晶粒形貌与实验结果吻合良好,证明该模型能有效预测不同热处理条件下HG-80钢的晶粒长大过程。 展开更多
关键词 HG-80钢 level Set方法 晶粒长大 Burke-Turnbull模型
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Mineralization at Different Structural Levels in the Crust 被引量:1
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作者 LI Saisai ZHANG Hongrui HOU Zengqian 《Acta Geologica Sinica(English Edition)》 2025年第4期1042-1058,共17页
Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels... Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels and mineralization remains limited.In this study,we summarize the deformation patterns and associated mineral deposits observed at different crustal levels(i.e.,surface,shallow,middle,and deep structural levels,corresponding to depths of<2,2-8,8-15,and>15 km,respectively).Furthermore,we examine the genetic association between structural levels and metallogenesis,demonstrating that distinct structural levels are linked to specific types of mineralization.Key factors that vary across crustal levels include temperature,pressure,and fluid circulation.Ore-forming processes involve interactions between structures and fluids under varying temperatures and pressures.Structural levels influence mineralization by controlling the temperatures,pressures,and deformation mechanisms that drive the activation,migration,and enrichment of ore-forming materials. 展开更多
关键词 deformation MINERALIZATION structural control structural level crustal level
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Effects of water level variations on the water quality of Huayang Lakes,China 被引量:1
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作者 AN Lesheng LIU Chun +3 位作者 FAN Zhongya LIAO Kaihua WANG Wencai WANG Nan 《Journal of Geographical Sciences》 2025年第1期173-188,共16页
To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend tes... To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test,box plots,and violin plots.The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes,with an average water level of 12.82 m and a monthly range of 11.21–17.24m.Since 2017,the water level of Huayang Rivers has shown a decreasing trend of–0.02 m/a.Total phosphorus(TP)has become the primary pollutant.The TP concentrations in Longgan Lake(the largest lake)during the dry,rising,flood,and retreating seasons from 2015 to 2023were 0.083,0.061,0.050,and 0.059 mg/L,respectively.The effect of water level on TP was mainly observed during the low-water period.When the water level in the dry season rose to 12.25 and 13.00 m,the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8%and 33.3%,respectively.During the dry season,wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes.This led to drastic fluctuations in TP concentration,reducing the correlation between water level and TP.When external control is limited,the water level during the dry season should be maintained between 12.25 and 13.0 m.Additionally,it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans)in the Huayang Rivers. 展开更多
关键词 shallow lake water level water quality total phosphorus Huayang Lakes
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Reservoir water level prediction using combined CEEMDAN-FE and RUN-SVM-RBFNN machine learning algorithms 被引量:1
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作者 Lan-ting Zhou Guan-lin Long +1 位作者 Can-can Hu Kai Zhang 《Water Science and Engineering》 2025年第2期177-186,共10页
Accurate prediction of water level changes in reservoirs is crucial for optimizing the operation of reservoir projects and ensuring their safety.This study proposed a method for reservoir water level prediction based ... Accurate prediction of water level changes in reservoirs is crucial for optimizing the operation of reservoir projects and ensuring their safety.This study proposed a method for reservoir water level prediction based on CEEMDAN-FE and RUN-SVM-RBFNN algorithms.By integrating the adaptive complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)method and fuzzy entropy(FE)with the new and highly efficient Runge–Kuta optimizer(RUN),adaptive parameter optimization for the support vector machine(SVM)and radial basis function neural network(RBFNN)algorithms was achieved.Regression prediction was conducted on the two reconstructed sequences using SVM and RBFNN according to their respective features.This approach improved the accuracy and stability of predictions.In terms of accuracy,the combined model outperformed single models,with the determination coefficient,root mean square error,and mean absolute error values of 0.9975,0.2418 m,and 0.1616 m,respectively.In terms of stability,the model predicted more consistently in training and testing periods,with stable overall prediction accuracy and a better adaptive ability to complex datasets.The case study demonstrated that the combined prediction model effectively addressed the environmental factors affecting reservoir water levels,leveraged the strength of each predictive method,compensated for their limitations,and clarified the impacts of environmental factors on reservoir water levels. 展开更多
关键词 Time series Environmental variable Reservoir water level Data decomposition Optimization Forecasting
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Enhanced electrode-level diagnostics for lithium-ion battery degradation using physics-informed neural networks 被引量:1
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作者 Rui Xiong Yinghao He +2 位作者 Yue Sun Yanbo Jia Weixiang Shen 《Journal of Energy Chemistry》 2025年第5期618-627,共10页
For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models... For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models and physical models,each offering unique advantages but also facing limitations.Physics-informed neural networks(PINNs)provide a robust framework to integrate data-driven models with physical principles,ensuring consistency with underlying physics while enabling generalization across diverse operational conditions.This study introduces a PINN-based approach to reconstruct open circuit voltage(OCV)curves and estimate key ageing parameters at both the cell and electrode levels.These parameters include available capacity,electrode capacities,and lithium inventory capacity.The proposed method integrates OCV reconstruction models as functional components into convolutional neural networks(CNNs)and is validated using a public dataset.The results reveal that the estimated ageing parameters closely align with those obtained through offline OCV tests,with errors in reconstructed OCV curves remaining within 15 mV.This demonstrates the ability of the method to deliver fast and accurate degradation diagnostics at the electrode level,advancing the potential for precise and efficient battery health management. 展开更多
关键词 Lithium-ion batteries Electrode level Ageing diagnosis Physics-informed neural network Convolutional neural networks
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Stratigraphic Forward Modeling of Late Quaternary Fluvial Dynamics in the Indus River Delta, Pakistan: Insights into Sea Level-Driven Sedimentary Evolution 被引量:1
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作者 HASSAN Hafiz Ahmed Raza LIU Keyu +3 位作者 LIU Jianliang MUNAWAR Muhammad Jawad REHMAN Saif Ur HUSSAIN Abid 《Journal of Ocean University of China》 2025年第6期1500-1518,共19页
Fluvial systems play a crucial role in coastal and riverine ecosystems, making it essential to understand their responses to sea level changes for preserving biodiversity and managing natural resources. The evolution ... Fluvial systems play a crucial role in coastal and riverine ecosystems, making it essential to understand their responses to sea level changes for preserving biodiversity and managing natural resources. The evolution of the modern Indus River Delta offers a rare opportunity to study the interplay between sea level fluctuations, tectonism, sediment supply, and the corresponding fluvial responses. This study employs the ‘SedSim' stratigraphic forward model to simulate the delta's evolution from 200 kyr to the next5 kyr, drawing on data from field observations, Landsat imagery, digital elevation models, and previous studies. The model consists of 205 layers, each representing a 1-kyr time step, covering the last two glacial-interglacial cycles. Between 200 kyr and 130 kyr, during a lowstand period, sedimentation on the delta plain continued due to partial flow from the Indus River. During the last interglacial(130–60 kyr), rising sea levels led to peak sediment deposition, characteristic of a highstand phase. From 60 kyr to 18 kyr, sea levels dropped to their lowest during the Last Glacial Maximum(LGM), resulting in extensive erosion and minimal deposition on the delta plain. From 18 kyr to the present, rapidly rising sea levels, coupled with intensified monsoon activity, increased sedimentation rates and triggered avulsion and aggradation processes. The model accurately predicted depositional thickness across the delta plain, indicating a maximum of ca. 200 m at the shoreline platform, ca. 175 m in the northeastern delta, and ca. 100 m in the central delta. The study underscores the delta's vulnerability to future sea level rise, which–at a projected rate of 1 m/kyr–could significantly influence the densely populated, low-lying delta plain. These findings offer valuable insights into the geomorphic evolution of the Indus Delta and emphasize the socioeconomic implications of sea level change, underscoring the importance of proactive management and adaptation strategies. 展开更多
关键词 fluvial responses sea level changes glacial-interglacial cycle sedimentary evolution stratigraphic forward modeling Indus Delta
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A Scoping Review on the Professional Self-Concept of Undergraduate Nursing Students
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作者 Juan Wang Zhilian Wu +4 位作者 Zheng Tian Wenwen Yang Haiyan Wu Zhangzhen Sun Lishuo Gao 《Journal of Clinical and Nursing Research》 2025年第1期146-156,共11页
Objective: To conduct a scoping review of research on the professional self-concept (PSC) of undergraduate nursing students, comprehensively analyzing its status, influencing factors, and significance, and providing a... Objective: To conduct a scoping review of research on the professional self-concept (PSC) of undergraduate nursing students, comprehensively analyzing its status, influencing factors, and significance, and providing a reference for enhancing the PSC of undergraduate nursing students in China. Methods: Using the methodological framework of Arksey and O’Malley’s scoping review, six literature databases were searched, including CNKI, Wanfang, Chinese Biomedical Literature Database, PudMed, Web of Science, and ScienceDirect. Studies on the factors influencing undergraduate nursing students’ PSC from database inception to July 31, 2023, were reviewed and data extracted. Results: A total of 1,955 articles were retrieved, and 27 studies were included. The current status of PSC primarily focuses on self-perception. Factors influencing undergraduate nursing students’ PSC are mainly individual and demographic, while external factors include various teaching methods and environments. PSC impacts professional maturity, mental health, self-concept, and pre-internship stress among nursing students. Conclusion: PSC profoundly influences undergraduate nursing students’ future career choices and professional development. Nursing educators and administrators should adopt measures to enhance and improve PSC levels, thereby fostering a larger pool of nursing professionals. 展开更多
关键词 Undergraduate nursing students Professional self-concept Scoping review
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Establishment of Diagnostic Reference Levels for Childhood Head CT in the District of Abidjan in Côte d’Ivoire
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作者 Koutoua Joseph Anouan Raïssa-Michelle Kabas +1 位作者 Jean-Paul Kouao Aboubakar Sidiki Diabaté 《World Journal of Nuclear Science and Technology》 2025年第1期45-52,共8页
Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study... Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study aims to survey the level of radiation doses delivered to child patients during head exams in CT imaging to set up the Dosimetric Reference Levels (DRLs), a routine dose optimization tool, based on data acquired at the University Hospital of Angré (UHA), the University Hospital of Treichville (UHT) and the Polyclinic Hospital Farah (Farah) for optimizing procedures in Ivorian hospitals. Prospectively performed on 334 CT images of 186 child patients, this study was carried out on CT systems such as Hitachi Scenaria, Sinovision Insitum, and Philips Incisive used respectively at UHA, UHT and Farah. Children’s scan data were classified into four age bands: vol or dose-length product as DLP) value, whatever the hospital, increases with respect to the age of child patients. Based on the 75th percentile of the whole dose distributions, the DRLs of the CTDIvol is 54.37 mGy whatever the age groups and those of the DLP with respect to age bands are 1224.55 mGy∙cm, 1414.06 mGy∙cm, 1632.24 mGy.cm and 1544.57 mGy∙cm, respectively. The averaged values of CTDIvol and DLP smaller than the corresponding DRLs values suggest that practices in our three facilities are optimized. However, comparing our results with those from different international studies, we see that the CTDIvol and DLP values obtained in the present work are higher. These results suggest additional surveys to ensure our DRLs values and efforts from radiologists, imaging technicians and medical physicists to strengthen clinical procedures for the radiation protection of children undergoing CT scans in Côte d’Ivoire. 展开更多
关键词 Computed Tomography Childhood Head Imaging Radiation Protection Diagnostic Reference levels
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Effect of minimum and maximum electrical stimulation levels on sound field thresholds,and speech perception in children using the Advanced Bionics Cochlear Implant
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作者 Muthuselvi Thangaraj Ravikumar Arunachalam +1 位作者 Madhuri Gore Ajith Kumar Uppunda 《Journal of Otology》 2025年第3期170-175,共6页
BackgroundIt's crucial to study the effect of changes in thresholds(T)and most comfortable levels(M)on behavioral measurements in young children using cochlear implants.This would help the clinician with the optim... BackgroundIt's crucial to study the effect of changes in thresholds(T)and most comfortable levels(M)on behavioral measurements in young children using cochlear implants.This would help the clinician with the optimization and validation of programming parameters.ObjectiveThe study has attempted to describe the changes in behavioral responses with modification of T and M levels.MethodsTwenty-five participants in the age range 5 to 12 years using HR90K/HiFocus1J or HR90KAdvantage/HiFocus1J with Harmony speech processors participated in the study.A decrease in T levels,a rise in T levels,or a decrease in M levels in the everyday program were used to create experimental programs.Sound field thresholds and speech perception were measured at 50 dBHL for three experimental and everyday programs.ConclusionThe results indicated that only reductions of M levels resulted in significantly(p<0.01)poor aided thresholds and speech perception.On the other hand,variation in T levels did not have significant changes in either sound field thresholds or speech perception.The results highlight that M levels must be correctly established in order to prevent decreased speech perception and audibility. 展开更多
关键词 T levels M levels sound field threshold speech perception
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Diagnostic Reference Levels, Protection of Patients and the Environment against Harmful Effects of X-Rays: Practice of Pediatric Radiology in Six General Reference Hospitals of the Kongo Central Province, DRC
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作者 Minga Barthelemy Bope Kwete Pembi Francy Pembi +13 位作者 Luwaya Ndombasi Blanchard Ipende Lansikub Jean Sokomoy Nankwa Joséphine Mukadi Mukadi Jules Thomas Byeka Mukambilwa Dorksin Kapia Patrice Milambo Binkedi Ngoma Richard Omombo Ngongo Timothée Mbiango Mabanza Francine Kafinga Ketibula Charly Nkwadi Katolo Adolphe Ngongo Mulemba Tchite Aya Nkole Benjamin Kafinga Luzolo Emery Masandi Milondo Alphonse 《Journal of Biosciences and Medicines》 2025年第1期47-59,共13页
The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, ... The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, including 10 radiologists working in the hospitals covered by the survey, to assess the practice of pediatric radiology and the degree of compliance with radiation protection principles for the safety of children and the environment. We collected radiophysical parameters to calculate entrance doses in pediatric radiology in radiology departments to determine the dosimetric level by comparison with the diagnostic reference levels of the International Commission on Radiological Protection (ICRP). All in all, we found that in Kongo Central in the DRC, many health personnel surveyed reported that more than 30% of requested radiological examinations are not justified. Also, after comparing the entrance doses produced in the surveyed departments with those of the International Commission on Radiological Protection (ICRP), a statistically significant difference was found in pediatric radiology between the average doses in five out of six surveyed departments and those of the ICRP. Therefore, almost all of the surveyed departments were found to be highly irradiating in children, while excessive X-ray irradiation in children can have significant effects due to their increased sensitivity to radiation. Among the risks are: increased cancer risks, damage to developing cells, potential genetic effects, and neurological effects. This is why support for implementing radiation protection principles is a necessity to promote the safety of patients and the environment against the harmful effects of X-rays in conventional radiology. 展开更多
关键词 Diagnostic Reference levels (DRLs) Radiation Protection Environment and Pediatric Radiology
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Unraveling contributors to stepwise water level variations in the Zhujiang River Estuary
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作者 Bo Li Hao Yang +4 位作者 Jing Liu Feng Liu Suying Ou Jianliang Lin Huayang Cai 《Acta Oceanologica Sinica》 2025年第11期50-68,共19页
Quantifying spatiotemporal variations in water levels and their responses to external drivers(e.g.,morphology,river discharge,and sea level)is critical for sustainable water resource management.However,simple methods ... Quantifying spatiotemporal variations in water levels and their responses to external drivers(e.g.,morphology,river discharge,and sea level)is critical for sustainable water resource management.However,simple methods for distinguishing the impacts of upstream river discharge,downstream sea level,and morphological changes on estuarine water levels remain limited.This study applied a revised triple linear regression model to reconstruct historical water levels(1965-2017)in the highly human-modified Zhujiang River Estuary(ZRE).The strong agreement between reconstructed and observed water levels(root mean square error<0.17 m;coefficient of determination>0.90)confirms the model reliability in quantifying drivers of water level variations.Results show morphological evolution as the dominant factor,causing an average water level decrease of 0.13 m,with declines increasing upstream from the estuary mouth.Sea level rise moderately elevated water levels by approximately 0.08 m on average.Reservoir regulation altered flow distribution and seasonal discharge patterns,weakening river discharge effects on downstream water levels in the lower West River,yet strengthening effects in the lower North River,averaging a 0.09 m water level decrease.These alterations further modified spatial water level slopes:reduced slopes in the lower West River primarily resulted from discharge changes,while morphological evolution dominated in the lower North River.Scenario simulations revealed significant water level responses to extreme events:an upstream discharge increase from 25000 m^(3)/s to 55000 m^(3)/s elevated upstream water levels by 3.47 m on average;relative sea level rise during storm surges from 1.50 m to 3.00 m increased downstream water levels by 1.34 m.These findings provide valuable guidance for flood prevention and water resource management in the ZRE and similarly modified estuaries worldwide. 展开更多
关键词 water level triple linear regression model river discharge sea level water resource management
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Could Glacier Geoengineering Freeze Sea Level Rise?
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作者 Mitch Leslie 《Engineering》 2025年第2期12-14,共3页
The Thwaites Glacier in western Antarctica(Fig. 1) keeps glaciologists and climate scientists awake at night. The 120 kmwide glacier loses about 45 billion tonnes of ice each year, accounting for about 4% of global se... The Thwaites Glacier in western Antarctica(Fig. 1) keeps glaciologists and climate scientists awake at night. The 120 kmwide glacier loses about 45 billion tonnes of ice each year, accounting for about 4% of global sea level rise [1]. If it melted completely, sea levels would climb 65 cm, and follow-on effects could lead to a 3 m increase [2]. But if some scientists' vision becomes reality, in 10–15 years construction crews will sail into the Amundsen Sea off Antarctica to begin building an 80 km long underwater curtain that will shield the glacier from the warm currents that are accelerating its decline [3]. 展开更多
关键词 glaciologists glacier geoengineering sea level rise ice loss global sea level rise Thwaites Glacier thwaites glacier climate scientists
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Associations between Rejective Parenting Style and Academic Anxiety among Chinese High School Students:The Chain Mediation Effect of Self-Concept and Positive Coping Style
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作者 Dexian Li Wencan Li +1 位作者 Xin Lin Xingchen Zhu 《International Journal of Mental Health Promotion》 2025年第1期1-17,共17页
Background:The phenomenon of academic anxiety has been demonstrated to exert a considerable influence on students’academic engagement,leading to the emergence of a phenomenon known as“learned helplessness”and under... Background:The phenomenon of academic anxiety has been demonstrated to exert a considerable influence on students’academic engagement,leading to the emergence of a phenomenon known as“learned helplessness”and undermining the selfconfidence and motivation of high school students.Using acceptance-rejection theory,this study elucidated how a rejective parenting style affects Chinese high school students’academic anxiety and explored the urban-rural heterogeneity of this relationship.Methods:Data were analyzed using a stratified whole-cluster random sampling method.There are a total of 30,000 high school students in the three regions of northern and central China(from Shanxi,Hebei and Henan).A sample of 2286 high school students aged 14–19 years was ultimately selected from 2760 respondents for this investigation,which was conducted at the beginning of the 2023 school year.Pearson correlation,ordinary least squares(OLS)regression analysis,path analysis,and Fisher’s permutation test(FPT)were used to examine the effects of rejective parenting style on high school students’academic anxiety.Results:Results indicated a significant positive predictive effect between rejective parenting style and academic anxiety among high school students(β=0.815,t=116.211,p<0.001).Students’self-concept was significantly positively related to positive coping style(β=0.424,t=21.208,p<0.001)and chain-mediated this relationship.Therefore,this parenting style may indirectly mitigate academic anxiety through these mediators.The study also found that the effect of rejective parenting style on academic anxiety varied by students’residential background and was more pronounced in urban areas(0.226)than in rural areas(0.130).Conclusion:The research underscores the imperative for Chinese families to reexamine their utilization of rejection parenting and to prioritize the cultivation of students’intrinsic attributes.These findings offer a theoretical framework and practical evidence for policymakers and educators to develop efficacious and targeted interventions.In particular,greater attention should be directed towards the discrepancies in the manifestation of emotional and academic anxiety between urban and rural students,and prompt guidance should be furnished. 展开更多
关键词 Rejective parenting style academic anxiety self-concept positive coping style chain mediating effects residence heterogeneity Chinese high school students
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Fluctuations of Water Table Level in a Subtropical Peatland,Central China
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作者 Guang Yang Yiming Zhang Xianyu Huang 《Journal of Earth Science》 2025年第2期441-449,共9页
Water level is the overriding control on carbon cycles in peatlands,which are important for global carbon cycles and ecosystem services.To date,our knowledge of the pattern of water level fluctuations in peatlands and... Water level is the overriding control on carbon cycles in peatlands,which are important for global carbon cycles and ecosystem services.To date,our knowledge of the pattern of water level fluctuations in peatlands and the influence of precipitation and air temperature on them in the subtropical remains poor.In this study,we conducted continuous high-resolution monitoring of water levels from 2014 to 2021 in the Dajiuhu peatland,a typically subtropical peatland in central China.Monitoring results showed that the water level had strong annual(370 days) and seasonal(130 days) oscillations in the Dajiuhu peatland.The annual oscillation is associated with both precipitation and temperature,while the seasonal oscillation is mainly controlled by precipitation.In addition,the depth of peat surface to the water table(DWT) has weak but significant correlations with precipitation and temperature on the daily and weekly scales(r = 0.1–0.21,p<0.01).Once replacing DWT with water table fluctuation cumulation,the correlation coefficients increase apparently(r = 0.47–0.69,p<0.01),especially on the monthly scale.These findings highlight a more important role of the fluctuation than the mean position of water level and have the potential to improve the interpretation of water-level related paleoenvironmental proxies and the understanding of the relationship between water level and biogeochemical processes. 展开更多
关键词 water level monitoring subtropical peatland PRECIPITATION temperature HYDROLOGY
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Separation between water and land in synthetic aperture radar images based on improved level set model
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作者 Jixiang Liu Xueyun Wei +4 位作者 Junxiao Li Wei Zheng Biao Jin Youbing Feng Caiping Xi 《Acta Oceanologica Sinica》 2025年第7期132-146,共15页
Separation between water and land is vital for marine scientific research and coastal zone planning and management.The contrasting backscatter properties of land and ocean enable clear water edge line identification i... Separation between water and land is vital for marine scientific research and coastal zone planning and management.The contrasting backscatter properties of land and ocean enable clear water edge line identification in synthetic aperture radar(SAR)imagery.However,SAR images are prone to speckle noise,and the complexity of the water-land boundaries environment makes accurate water-land separation challenging.To overcome noise and complex background interference in remote sensing images,an improved level set method was employed to enhance water-land separation.In the traditional distance regularized level set method,the selection of the image correlation weight coefficient and the edge indicator function directly influences the accuracy of the final segmentation results.A novel level set segmentation algorithm incorporating an improved edge indicator function is proposed to efficiently and accurately separate the water edge lines in SAR images.The distance regularized level set evolution model is enhanced by incorporating the signed pressure force function as an adaptive parameter,which serves as an external constraint for curve evolution.A novel level set model with an adaptive edge indicator function,combining gradient and regional information,is proposed.Experimental results demonstrate that the proposed model enhances the accuracy of waterland separation in SAR images.However,further research is needed to evaluate its potential for detecting boundaries in diverse marine environments and across different types of SAR imagery. 展开更多
关键词 water-land separation SAR image segmentation level set
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Effectiveness of the combination of Fe tablets and beetroot juice in increasing Hb levels of pregnant women with anemia
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作者 Aulia Amini Baiq Nurbaety 《Frontiers of Nursing》 2025年第4期423-431,共9页
Objective:This study aims to determine the effectiveness of giving a combination of Fe tablets and beetroot juice in increasing hemoglobin(Hb)levels of pregnant women with anemia in the Mataram City area.Methods:This ... Objective:This study aims to determine the effectiveness of giving a combination of Fe tablets and beetroot juice in increasing hemoglobin(Hb)levels of pregnant women with anemia in the Mataram City area.Methods:This study was designed with quasi-experimental design with pre-test and post-test with control design.The location of this study was conducted in the city of Mataram on pregnant women with anemia.The sample of this study was pregnant women with mild anemia based on inclusion and exclusion criteria,divided into 2 groups:a control group and a treatment group of 15 respondents each,bringing the total respondents to 30 people.Analysis of Hb level measurement results was carried out using the independent sample t-test.Results:The results obtained in the treatment group(combination of beet juice and Fe tablets)were the mean pre-test of 9.93 mg/dL and post-test of 11.90 mg/dL(P-value=0.000),which means there is effectiveness in increasing hemoglobin levels while in the control group.Comparison of increased Hb levels of the control group and significantly different treatments marked by a P value of 0.001.Conclusions:the combination of Fe tablets and beetroot juice is effective in increasing Hb levels of pregnant women with anemia in the Mataram City area. 展开更多
关键词 ANEMIA beet juice EFFECTIVENESS Hb levels pregnant women
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Numerical simulation of vortex breakdown in a cylindrical tank with rotating bottom and free surface using level set method
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作者 Zepeng Zhao Qin Li +5 位作者 Feng Ye Haoliang Wang Jianfeng Wang Hui Yu Xiangyang Li Chao Yang 《Chinese Journal of Chemical Engineering》 2025年第1期293-300,共8页
A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown withi... A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown within the chamber,this study first establishes a computational fluid dynamics simulation coupled with the level set method.Verified by experimental results in literature,this method accurately simulates the position and shape of vortex breakdown,and also predicts the critical Reynolds numbers for the appearance and detachment of vortex breakdown bubbles from the center.Additionally,it precisely captures the gas-liquid interface and depicts the vortex breakdown phenomenon in the air above the liquid for the first time.Finally,it predicts the impact of physical property of gas-liquid systems on vortex breakdown in response to significant changes in viscosity of microbial process systems. 展开更多
关键词 Vortex breakdown level set Microbial cultivation Micro-bioreactor
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