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Noradrenergic excitation of astrocytes supports cognitive reserve
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作者 Robert Zorec Alexei Verkhratsky 《Neural Regeneration Research》 2026年第4期1546-1547,共2页
The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It ha... The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It has been suggested that the size of the brain(brain reserve) and the extent of neural connections acquired through life(neural reserve) set a threshold beyond which noticeable impairments occur.In contrast,cognitive reserve refers to the brain's ability to adapt and reo rganize stru cturally and functionally to resist damage and maintain function,including neural reserve and brain maintenance,resilience,and compensation(Verkhratsky and Zorec,2024). 展开更多
关键词 ASTROCYTES brain reserve cognitive reserve clinical symptoms noradrenergic excitation neural reserve neural connections brain cognitive reserve
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Oxidative steam reforming of HDPE pyrolysis volatiles on Ni catalysts:Effect of the support(Al_(2)O_(3),ZrO_(2),SiO_(2))and promoter(CeO_(2),La_(2)O_(3))on the catalyst performance
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作者 Mayra Alejandra Suarez Laura Santamaria +4 位作者 Gartzen Lopez Enara Fernandez Martin Olazar Maider Amutio Maite Artetxe 《Chinese Journal of Catalysis》 2025年第2期149-162,共14页
High density polyethylene(HDPE)pyrolysis and in-line oxidative steam reforming was carried out in a two-step reaction system consisting of a conical spouted bed reactor and a fluidized bed reactor.Continuous plastic p... High density polyethylene(HDPE)pyrolysis and in-line oxidative steam reforming was carried out in a two-step reaction system consisting of a conical spouted bed reactor and a fluidized bed reactor.Continuous plastic pyrolysis was conducted at 550℃ and the volatiles formed were fed in-line to the oxidative steam reforming step(space-time 3.12 gcat min gHDPE−1;ER=0.2 and steam/plastic=3)operating at 700℃.The influence Ni based reforming catalyst support(Al_(2)O_(3),ZrO_(2),SiO_(2))and promoter(CeO_(2),La_(2)O_(3))have on HDPE pyrolysis volatiles conversion and H_(2) production was assessed.The catalysts were prepared by the wet impregnation and they were characterized by means of N_(2) adsorption-desorption,X-ray fluorescence,temperature-programmed reduction and X-ray powder diffraction.A preliminary study on coke deposition and the deterioration of catalysts properties was carried out,by analyzing the tested catalysts through temperature programmed oxidation of coke,transmission electron microscopy,and N_(2) adsorption-desorption.Among the supports tested,ZrO_(2) showed the best performance,attaining conversion and H_(2) production values of 92.2% and 12.8 wt%,respectively.Concerning promoted catalysts,they led to similar conversion values(around 90%),but significant differences were observed in H_(2) production.Thus,higher H_(2) productions were obtained on the Ni/La_(2)O_(3)-Al_(2)O_(3) catalyst(12.1 wt%)than on CeO_(2) promoted catalysts due to La_(2)O_(3) capability for enhancing water adsorption on the catalyst surface. 展开更多
关键词 Plastic PYROLYSIS Oxidative steam reforming Ni catalyst Hydrogen
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Determinants in adopting cashless payments in Europe:a multilevel analysis
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作者 Jose Domingo Garcia‑Merino Leire San‑Jose Nerea San‑Martin 《Financial Innovation》 2025年第1期2148-2167,共20页
The use of electronic currency for transactions,denoting a cashless paradigm,has become increasingly common.However,this financial innovation is not prevalent in all countries.This study aims to explain the discrepanc... The use of electronic currency for transactions,denoting a cashless paradigm,has become increasingly common.However,this financial innovation is not prevalent in all countries.This study aims to explain the discrepancies across countries,including individual and country factors.It may be superficially posited that this lag in development stems from individual or microlevel usage challenges.However,the application of the Technology Acceptance Model highlights the presence of overarching characteristics conducive to extensive adoption.Thus,an additional stratum,the multilevel perspective,needs to be examined.This analytical framework incorporates not only individual attributes but also the sociotechnical framework or mesolevel factors in which they operate.A multilevel econometric model is used.The results of these analyses show that the impact on the adoption of cashless payments extends beyond individual factors(attitude to technology use,perceived usefulness,and perceived ease of use).Our primary contribution,conceptually and empirically,is to broaden the analysis vision.A comprehensive multilevel analysis revealed that broader contextual elements,such as infrastructure and national skills,exert a significant influence on the adoption of cashless transactions.Consequently,the widespread acceptance of cashless payment methods is not only contingent on individual choices but is also a collective phenomenon in which the surrounding environment plays a crucial role as a catalyst for the end users in the cashless economy. 展开更多
关键词 Cashless payment Multilevel perspective Technology acceptance model Microlevel Mesolevel
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Small extrachromosomal circular DNA in amyotrophic lateral sclerosis matter
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作者 Marcos J.Arauzo-Bravo Daniela Gerovska +1 位作者 Matthias Schwab Alexandra Kretz 《Neural Regeneration Research》 SCIE CAS 2025年第5期1411-1413,共3页
Comprehensive studies identify motor neuron spectrum disorders including amyotrophic lateral sclerosis(ALS)as globally rising fatal disorders with the highest prevalence in aging populations,influenced by ethnicity an... Comprehensive studies identify motor neuron spectrum disorders including amyotrophic lateral sclerosis(ALS)as globally rising fatal disorders with the highest prevalence in aging populations,influenced by ethnicity and ancestry(GBD 2016 Motor Neuron Disease Colla borators,2018).While~10% of diagnoses involve a family history(fALS),most cases are considered sporadic(sALS).However,population-based studies suggest that even cases without a common index mutation impart heritability(Ryan et al.,2019),indicating a crucial role of rare and as yet unknown genetic denominators. 展开更多
关键词 amyotrophic SCLEROSIS
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Corrections to scaling in the 2D φ^(4) model:Monte Carlo results and some related problems
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作者 J.Kaupuzs R.V.N.Melnik 《Communications in Theoretical Physics》 2025年第6期210-222,共13页
Monte Carlo(MC) simulations have been performed to refine the estimation of the correction-toscaling exponent ω in the 2D φ^(4)model,which belongs to one of the most fundamental universality classes.If corrections h... Monte Carlo(MC) simulations have been performed to refine the estimation of the correction-toscaling exponent ω in the 2D φ^(4)model,which belongs to one of the most fundamental universality classes.If corrections have the form ∝ L^(-ω),then we find ω=1.546(30) andω=1.509(14) as the best estimates.These are obtained from the finite-size scaling of the susceptibility data in the range of linear lattice sizes L ∈[128,2048] at the critical value of the Binder cumulant and from the scaling of the corresponding pseudocritical couplings within L∈[64,2048].These values agree with several other MC estimates at the assumption of the power-law corrections and are comparable with the known results of the ε-expansion.In addition,we have tested the consistency with the scaling corrections of the form ∝ L^(-4/3),∝L^(-4/3)In L and ∝L^(-4/3)/ln L,which might be expected from some considerations of the renormalization group and Coulomb gas model.The latter option is consistent with our MC data.Our MC results served as a basis for a critical reconsideration of some earlier theoretical conjectures and scaling assumptions.In particular,we have corrected and refined our previous analysis by grouping Feynman diagrams.The renewed analysis gives ω≈4-d-2η as some approximation for spatial dimensions d <4,or ω≈1.5 in two dimensions. 展开更多
关键词 Monte Carlo simulations universality classes linear lattice sizes Binder cumulant corrections scaling scaling corresponding ps MODEL binder cumulant
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Intelligent sitting postural anomaly detection system for wheelchair users with unsupervised techniques
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作者 Patrick Vermander Aitziber Mancisidor +2 位作者 Raffaele Gravina Itziar Cabanes Giancarlo Fortino 《Digital Communications and Networks》 2025年第3期622-633,共12页
Detecting sitting posture abnormalities in wheelchair users enables early identification of changes in their functional status.To date,this detection has relied on in-person observation by medical specialists.However,... Detecting sitting posture abnormalities in wheelchair users enables early identification of changes in their functional status.To date,this detection has relied on in-person observation by medical specialists.However,given the challenges faced by health specialists to carry out continuous monitoring,the development of an intelligent anomaly detection system is proposed.Unlike other authors,where they use supervised techniques,this work proposes using unsupervised techniques due to the advantages they offer.These advantages include the lack of prior labeling of data,and the detection of anomalies previously not contemplated,among others.In the present work,an individualized methodology consisting of two phases is developed:characterizing the normal sitting pattern and determining abnormal samples.An analysis has been carried out between different unsupervised techniques to study which ones are more suitable for postural diagnosis.It can be concluded,among other aspects,that the utilization of dimensionality reduction techniques leads to improved results.Moreover,the normality characterization phase is deemed necessary for enhancing the system’s learning capabilities.Additionally,employing an individualized approach to the model aids in capturing the particularities of the various pathologies present among subjects. 展开更多
关键词 Sitting posture monitoring Anomaly detection Assistive technology Pressure sensors Unsupervised techniques INDIVIDUALIZATION WHEELCHAIR
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他们抓住了“薛定谔的猫”——2025年诺贝尔物理学奖与宏观量子奇迹
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作者 杨磊 周士杰 +1 位作者 丁泳程 江奕骏 《自然杂志》 2025年第6期454-460,共7页
2025年诺贝尔物理学奖授予约翰·克拉克(John Clarke)、米歇尔·德沃雷(Michel H. Devoret)和约翰·马蒂尼斯(John M. Martinis),以表彰他们在宏观电路中首次实验发现“量子隧穿”与“能量量子化”的奠基性贡献。他们的研... 2025年诺贝尔物理学奖授予约翰·克拉克(John Clarke)、米歇尔·德沃雷(Michel H. Devoret)和约翰·马蒂尼斯(John M. Martinis),以表彰他们在宏观电路中首次实验发现“量子隧穿”与“能量量子化”的奠基性贡献。他们的研究将著名的“薛定谔的猫”思想实验变为现实。通过厘米尺度的超导电路,他们成功捕捉到由数十亿电子对协同形成的宏观量子叠加态。实验不仅观测到该宏观系统如拥有“穿墙术”般穿越经典势垒(量子隧穿),并揭示其能量如楼梯台阶般是分立的(能量量子化)。这项工作彻底打破了量子现象仅存在于微观世界的界限,为超导量子计算技术奠定了坚实的物理与实验基础。如今,以他们开创的约瑟夫森结为核心构建的量子比特,正驱动着谷歌、IBM等公司的量子处理器,标志着人类从“观察量子”迈向“建造量子”的新时代。 展开更多
关键词 诺贝尔物理学奖 量子隧穿 能量量子化 薛定谔的猫
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Applications of Carbon-Based Multivariable Chemical Sensors for Analyte Recognition
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作者 Lin Shi Jian Song +5 位作者 Yu Wang Heng Fu Kingsley Patrick-Iwuanyanwu Lei Zhang Charles H.Lawrie Jianhua Zhang 《Nano-Micro Letters》 2025年第10期417-452,共36页
Over recent decades,carbon-based chemical sensor technologies have advanced significantly.Nevertheless,significant opportunities persist for enhancing analyte recognition capabilities,particularly in complex environme... Over recent decades,carbon-based chemical sensor technologies have advanced significantly.Nevertheless,significant opportunities persist for enhancing analyte recognition capabilities,particularly in complex environments.Conventional monovariable sensors exhibit inherent limitations,such as susceptibility to interference from coexisting analytes,which results in response overlap.Although sensor arrays,through modification of multiple sensing materials,offer a potential solution for analyte recognition,their practical applications are constrained by intricate material modification processes.In this context,multivariable chemical sensors have emerged as a promising alternative,enabling the generation of multiple outputs to construct a comprehensive sensing space for analyte recognition,while utilizing a single sensing material.Among various carbon-based materials,carbon nanotubes(CNTs)and graphene have emerged as ideal candidates for constructing high-performance chemical sensors,owing to their well-established batch fabrication processes,superior electrical properties,and outstanding sensing capabilities.This review examines the progress of carbon-based multivariable chemical sensors,focusing on CNTs/graphene as sensing materials and field-effect transistors as transducers for analyte recognition.The discussion encompasses fundamental aspects of these sensors,including sensing materials,sensor architectures,performance metrics,pattern recognition algorithms,and multivariable sensing mechanism.Furthermore,the review highlights innovative multivariable extraction schemes and their practical applications when integrated with advanced pattern recognition algorithms. 展开更多
关键词 Carbon nanotubes GRAPHENE Field-effect transistors Gas sensors Biosensors
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Analysis of the Minute Differences between the Internal Structures of Green-Emitting Quantum Dots Via Synchrotron-Based X-Ray Photoelectron Spectroscopy
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作者 Dong-Jin Yun Nayoun Won +10 位作者 Young Mo Sung Tae-Gon Kim Taekhoon Kim Ane Etxebarria Kyungjae Lee SooHwan Sul Hyokeun Park SungJun Park Jung-Hwa Kim Shinae Jun Ethan Crumlin 《Energy & Environmental Materials》 2025年第1期313-322,共10页
The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectros... The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectroscopy(XPS)is designed here to accurately characterize the chemical and structural differences between different QDs.This method enables the determination of the reason for the minimal differences between the optical properties of different QDs depending on the synthesis process,which is difficult to determine using conventional methods alone.Combined with model simulations,the XPS spectra obtained at different photon energies reveal the internal structures and chemical-state distributions of the QDs.In particular,the QD synthesized under optimal conditions demonstrates a relatively lower degree of oxidation of the core and more uniformly stacked ZnSe/ZnS shell layers.The internal structures and chemical-state distributions of QDs are closely related to their optical properties.Finally,the synchrotron-based XPS proposed here can be applied to compare nearly equivalent QDs with slightly different optical properties. 展开更多
关键词 chemical state indium phosphide-based quantum dot inelastic mean free path internal structure synchrotron-based X-ray photoelectron spectroscopy
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Exploring the role of armed conflict in progress toward Sustainable Development Goals:Global patterns,regional differences,and driving mechanisms
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作者 Di Wang Zhenci Xu +3 位作者 Unai Pascual Lei Liu Waqar Ahmad Dong Jiang 《Geography and Sustainability》 2025年第6期90-100,共11页
The Sustainable Development Goals(SDGs)represent a solemn commitment by United Nations member states,but achieving them faces numerous challenges,particularly armed conflicts.Here,we analyzed the impact of armed confl... The Sustainable Development Goals(SDGs)represent a solemn commitment by United Nations member states,but achieving them faces numerous challenges,particularly armed conflicts.Here,we analyzed the impact of armed conflict on SDG progress and its driving mechanism through causal inference methods and machine learning technique.The results show that between 2000 and 2021,armed conflicts slowed overall SDG progress by 3.43%,equivalent to a setback of 18 years.The Middle East was the most affected region,with a 6.10%slowdown in progress.The impact of different types of conflict varies across specific goals:interstate conflicts primarily affect SDG 5(Gender Equality)and SDG 7(Affordable and Clean Energy),while intrastate conflicts have a larger impact on SDG 4(Quality Education)and SDG 9(Industry,Innovation and Infrastructure).Additionally,SDG 15(Life on Land)is severely affected by both types of conflict,with long-term consequences.As armed conflicts increase,the development progress would regress rapidly in a non-linear manner.To achieve the SDGs by 2030,it is crucial not only to prevent conflicts but also to proactively address and mitigate their impacts on development. 展开更多
关键词 Geopolitical conflict SDGs Causal inference Middle East South Asia Sub-Saharan Africa
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Targeting Microglial Connexin43 Hemichannels:A Novel Therapeutic Avenue for Alzheimer’s Disease
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作者 Chenju Yi Yixun Su Alexei Verkhratsky 《Neuroscience Bulletin》 2025年第11期2095-2099,共5页
Alzheimer's disease(AD),the leading cause of dementia,remains a formidable challenge to neurology.Despite decades of research focused on amyloid-β(Aβ)and tau pathologies,most clinical trials targeting these mole... Alzheimer's disease(AD),the leading cause of dementia,remains a formidable challenge to neurology.Despite decades of research focused on amyloid-β(Aβ)and tau pathologies,most clinical trials targeting these molecules failed,highlighting the need for alternative strategies[1].Recent attention has turned to neuroinflammation,particularly the role of microglia,the brain's resident immune cells[1].Microglia are central to AD progression.They can degrade Aβplaques and protect neurons,but may also exacerbate neurotoxicity through chronic inflammation[1]. 展开更多
关键词 degrade plaques neuroinflammation connexin hemichannels clinical trials microglia dementia Alzheimers disease exacerbate neurotox
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One-year clinical events according to frailty in older patients with non-ST elevation acute coronary syndrome undergoing coronary angiography:an analysis of the IMPACT-TIMINGGO study
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作者 Pablo Díez-Villanueva Pedro Cepas-Guillén +12 位作者 María Thiscal López Lluva Alfonso Jurado-Román Pablo Bazal-Chacón Martín Negreira-Caamaño Iván Olavarri-Miguel Ane Elorriaga Ricardo Rivera-López David Escribano Pablo Salinas María Martínez-Avial Antonio Martínez-Guisado Clea González-Maniega Felipe Díez-Delhoyo 《Journal of Geriatric Cardiology》 2025年第1期159-168,共10页
Objective To evaluate the prevalence and one-year prognosis associated with frailty in a contemporary cohort of older patients with non-ST-elevation acute coronary syndrome(NSTEACS).Methods The IMPACT-TIMING-GO regist... Objective To evaluate the prevalence and one-year prognosis associated with frailty in a contemporary cohort of older patients with non-ST-elevation acute coronary syndrome(NSTEACS).Methods The IMPACT-TIMING-GO registry(IMPACT of Time of Intervention in patients with Myocardial Infarction with Non-ST seGment elevation.ManaGement and Outcomes)prospectively included 1020 patients with NSTEACS undergoing invasive coronary angiography between April and May 2021.For this sub-study,patients≥65 years were selected.Frailty was assessed according to FRAIL scale.We studied all-cause mortality and the composite of all-cause mortality or all-cause hospitalizations at one-year follow-up after discharge.Results Five hundred and sixty seven patients(mean age:75.8±6.7 years,28.2%women)were included:316(55.7%)were robust,183(32.3%)prefrail,and 68(12.0%)frail.Frail patients were significantly older,more often women,and presented a worse baseline clinical profile.There were no differences among groups regarding pretreatment with a P2Y12 inhibitor.An urgent angiography(<24 h)was less frequently performed in frail patients,with no differences regarding revascularization approach or in main in-hospital adverse events,although acute kidney disease occurred more frequently in frail patients.At 1-year follow-up,20 patients died(3.6%).Chronic kidney disease was independently associated with 1-year all-cause death,although a trend towards higher mortality was observed in frail patients(HR=3.01;95%CI:0.93-9.78;P=0.065).Frailty was independently associated with higher 1-year all-cause mortality or all-cause rehospitalizations(HR=2.23;95%CI:1.43-3.46;P<0.001)Conclusions In older patients with NSTEACS,frailty independently associates higher all-cause mortality or all-cause hospital admissions at one-year follow-up. 展开更多
关键词 patients CORONARY ANGIOGRAPHY
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华南衡阳盆地上白垩统黄土类似物的初步研究 被引量:2
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作者 石宇翔 吴驰华 +8 位作者 黄乐清 伊海生 李智武 焦海菁 杨嘉宝 秦江颖 张小凤 周亚楠 Juan Pedro RODRIGUEZ-LOPEZ 《地质学报》 EI CAS CSCD 北大核心 2023年第9期3101-3115,共15页
中国新生代黄土序列具有沉积速率高、连续性好等特点,记录了东亚地区持续的古气候动力学演化和重大地质事件信息。受区域构造-地貌和大气环流格局影响,中生代晚期华南发育了众多盆山型古沙漠系统且出露了巨厚的风成砂,但几乎未有学者提... 中国新生代黄土序列具有沉积速率高、连续性好等特点,记录了东亚地区持续的古气候动力学演化和重大地质事件信息。受区域构造-地貌和大气环流格局影响,中生代晚期华南发育了众多盆山型古沙漠系统且出露了巨厚的风成砂,但几乎未有学者提及黄土/黄土类似物的存在。本文通过粒度端元解析、野外露头的构型分析等手段,对衡阳盆地上白垩统红花套组进行了初步研究,识别出风成砂丘、砂席和泥滩等环境类型;并在泥滩环境中提取到黄土类似物的粒度组分信号,同时提出了黄土类似物的风成成因,总结了其形成-堆积过程。这项工作旨在探索白垩纪黄土类似物存在的可能性,为未来开展华南陆块中生代风尘记录研究提供契机。 展开更多
关键词 上白垩统 衡阳盆地 红花套组 风成沉积 黄土类似物
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不同固定床位置生物质热解挥发物蒸汽催化重整反应中焦炭的形成和演化 被引量:3
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作者 Enara Fernandez Laura Santamaria +5 位作者 Irati García Maider Amutio Maite Artetxe Gartzen Lopez Javier Bilbao Martin Olazar 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期101-116,共16页
对生物质热解挥发物蒸汽重整反应过程中催化剂的失活过程和主要机理进行了研究.在圆锥形喷动床反应器中于500℃进行生物质热解,随后在固定床反应器中于600℃进行重整反应;同时在不同轴向位置分析了催化剂位置对重整反应器的影响.采用N_... 对生物质热解挥发物蒸汽重整反应过程中催化剂的失活过程和主要机理进行了研究.在圆锥形喷动床反应器中于500℃进行生物质热解,随后在固定床反应器中于600℃进行重整反应;同时在不同轴向位置分析了催化剂位置对重整反应器的影响.采用N_(2)吸附-脱附、X射线衍射、扫描电镜、透射电镜、程序升温氧化、拉曼光谱和傅里叶变换红外光谱对失活样品进行表征.结果表明,焦炭沉积是初始催化剂活性衰减的主要原因,且没有观察到镍位点的烧结或氧化.随着反应的进行,沿着重整催化床观察到失活情况,焦炭沉积于催化剂内,其性质和组成取决于到达床中每个轴向位置的挥发物组成.在催化床的入口部分,焦炭沉积在Ni位点上,并且具有一定的含氧量.在更深的轴向床位置,催化剂与挥发性物质接触,该挥发性物质的组成已经明显改变,从而形成具有石墨化程度更高的焦炭,并且形成更多的缩合聚芳烃化合物.此外,沉积在所有失活样品上的焦炭没有呈现任何特定的形态,这也表明,无论所处的催化床位置和反应时间,焦炭均呈现无定形结构. 展开更多
关键词 生物质 热解 蒸汽重整 失活 积碳 氢气 生物油
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Systematic study of the dependence of magnetic and structural properties of Nd2Fe14B powders on the average particle size 被引量:5
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作者 J.F.Durán Perdomo G.A.Pérez Alcázar +3 位作者 H.D.Colorado J.A.Tabares L.E.Zamora J.J.S.Garitaonandia 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第9期961-968,I0002,共9页
A systematic study of the magnetic and structural properties dependence on the particle size was realized.For this,commercial NdFeB powder was separated into five different mean particle sizes using sieves.Besides,fro... A systematic study of the magnetic and structural properties dependence on the particle size was realized.For this,commercial NdFeB powder was separated into five different mean particle sizes using sieves.Besides,from the original powder,eleven samples were also produced by mechanical milling assisted by surfactant,using various milling times.A total of sixteen samples were studied by scanning electron microscopy(SEM),X-ray diffraction(XRD),vibrating sample magnetometry(VSM),and Mdssbauer spectrometry(MS).The particle sizes of the samples vary from the micrometer to the nanometer scale.The crystallite size decreases with decreasing particle size.XRD result indicates that the Nd2Fe14B phase is found in all the samples,and the presence of this phase is also corroborated by MS using six sextets for fitting their spectra,with an additional singlet corresponding to the Nd1.1Fe4B4 phase.The mean hyperfine magnetic field increases with increasing particle size because the magnetic dipolar interaction between the magnetic moment of the particles increases with particle size.From the VSM measurements the magnetic energy density(BH)max values were calculated for different particle sizes,and their maximum value of 34.45 MGOe is obtained for the sample with the particle size of 60μm. 展开更多
关键词 Hard magnetic material XRD Mossbauer spectrometry MAGNETIZATION Particle size Rare earths
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Breast Lesions Detection and Classification via YOLO-Based Fusion Models 被引量:6
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作者 Asma Baccouche Begonya Garcia-Zapirain +1 位作者 Cristian Castillo Olea Adel S.Elmaghraby 《Computers, Materials & Continua》 SCIE EI 2021年第10期1407-1425,共19页
With recent breakthroughs in artificial intelligence,the use of deep learning models achieved remarkable advances in computer vision,ecommerce,cybersecurity,and healthcare.Particularly,numerous applications provided e... With recent breakthroughs in artificial intelligence,the use of deep learning models achieved remarkable advances in computer vision,ecommerce,cybersecurity,and healthcare.Particularly,numerous applications provided efficient solutions to assist radiologists for medical imaging analysis.For instance,automatic lesion detection and classification in mammograms is still considered a crucial task that requires more accurate diagnosis and precise analysis of abnormal lesions.In this paper,we propose an end-to-end system,which is based on You-Only-Look-Once(YOLO)model,to simultaneously localize and classify suspicious breast lesions from entire mammograms.The proposed system first preprocesses the raw images,then recognizes abnormal regions as breast lesions and determines their pathology classification as either mass or calcification.We evaluated the model on two publicly available datasets,with 2907 mammograms from the Curated Breast Imaging Subset of Digital Database for Screening Mammography(CBIS-DDSM)and 235 mammograms from INbreast database.We also used a privately collected dataset with 487 mammograms.Furthermore,we suggested a fusion models approach to report more precise detection and accurate classification.Our best results reached a detection accuracy rate of 95.7%,98.1%and 98%for mass lesions and 74.4%,71.8%and 73.2%for calcification lesions,respectively on CBIS-DDSM,INbreast and the private dataset. 展开更多
关键词 Breast cancer DETECTION CLASSIFICATION YOLO deep learning FUSION
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Clearing the corpses: regulatory mechanisms, novel tools, and therapeutic potential of harnessing microglial phagocytosis in the diseased brain 被引量:4
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作者 Irune Diaz-Aparicio Sol Beccari +1 位作者 Oihane Abiega Amanda Sierra 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第10期1533-1539,共7页
Apoptosis is a widespread phenomenon that occurs in the brain in both physiological and pathological conditions. Dead ceils must be quickly removed to avoid the further toxic effects they exert in the pa- renchyma, a ... Apoptosis is a widespread phenomenon that occurs in the brain in both physiological and pathological conditions. Dead ceils must be quickly removed to avoid the further toxic effects they exert in the pa- renchyma, a process executed by microglia, the brain professional phagocytes. Although phagocytosis is critical to maintain tissue homeostasis, it has long been either overlooked or indirectly assessed based on microglial morphology, expression of classical activation markers, or engulfment of artificial phagocytic targets in vitro. Nevertheless, these indirect methods present several limitations and, thus, direct obser- vation and quantification of microglial phagocytosis is still necessary to fully grasp its relevance in the diseased brain. To overcome these caveats and obtain a comprehensive, quantitative picture of microglial phagocytosis we have developed a novel set of parameters. These parameters have allowed us to identify the different strategies utilized by microglia to cope with apoptotic challenges induced by excitotoxicity or inflammation. In contrast, we discovered that in mouse and human epilepsy microglia failed to find and engulf apoptotic ceils, resulting in accumulation of debris and inflammation. Herein, we advocate that the efficiency of microglial phagocytosis should be routinely tested in neurodegenerative and neuro- logical disorders, in order to determine the extent to which it contributes to apoptosis and inflammation found in these conditions. Finally, our findings point towards enhancing microglial phagocytosis as a novel therapeutic strategy to control tissue damage and inflammation, and accelerate recovery in brain diseases. 展开更多
关键词 MICROGLIA PHAGOCYTOSIS apoptosis impairment epilepsy brain diseases NEURODEGENERATION inflammation NEUROINFLAMMATION
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Drying Kinetics and Energy Consumption in Vacuum Drying Process with Microwave and Radiant Heating 被引量:4
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作者 M.Kamel J.I.Lombrana +1 位作者 C.de Elvira R.Rodríguez 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第6期809-813,共5页
The general objective of this work is to analyze energy input in a vacuum process with the incorporation of microwave heating. Thus, necessary criteria for designing an efficient freeze-drying operation are considered... The general objective of this work is to analyze energy input in a vacuum process with the incorporation of microwave heating. Thus, necessary criteria for designing an efficient freeze-drying operation are considered through the analysis of strategies based on the combination of different intensities of radiant and microwave heating.The other aim of this research topic is to study the kinetics of drying in relation to mass transfer parameters.Five freeze-drying strategies using both heating systems were used. Consequently, energy input could be related to diffusivity coefficients, temperature and pressure profiles during dehydration of the product and analyzed in comparison to a conventional freeze-drying process. 展开更多
关键词 vacuum microwave drying diffusivity constant ENERGY
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Machine Learning Techniques Applied to Electronic Healthcare Records to Predict Cancer Patient Survivability 被引量:2
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作者 Ornela Bardhi Begonya Garcia Zapirain 《Computers, Materials & Continua》 SCIE EI 2021年第8期1595-1613,共19页
Breast cancer(BCa)and prostate cancer(PCa)are the two most common types of cancer.Various factors play a role in these cancers,and discovering the most important ones might help patients live longer,better lives.This ... Breast cancer(BCa)and prostate cancer(PCa)are the two most common types of cancer.Various factors play a role in these cancers,and discovering the most important ones might help patients live longer,better lives.This study aims to determine the variables that most affect patient survivability,and how the use of different machine learning algorithms can assist in such predictions.The AURIA database was used,which contains electronic healthcare records(EHRs)of 20,006 individual patients diagnosed with either breast or prostate cancer in a particular region in Finland.In total,there were 178 features for BCa and 143 for PCa.Six feature selection algorithms were used to obtain the 21 most important variables for BCa,and 19 for PCa.These features were then used to predict patient survivability by employing nine different machine learning algorithms.Seventy-five percent of the dataset was used to train the models and 25%for testing.Cross-validation was carried out using the StratifiedKfold technique to test the effectiveness of the machine learning models.The support vector machine classifier yielded the best ROC with an area under the curve(AUC)=0.83,followed by the KNeighborsClassifier with AUC=0.82 for the BCa dataset.The two algorithms that yielded the best results for PCa are the random forest classifier and KNeighborsClassifier,both with AUC=0.82.This study shows that not all variables are decisive when predicting breast or prostate cancer patient survivability.By narrowing down the input variables,healthcare professionals were able to focus on the issues that most impact patients,and hence devise better,more individualized care plans. 展开更多
关键词 Machine learning EHRs feature selection breast cancer prostate cancer SURVIVABILITY FINLAND
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