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The neuroimaging of neurodegenerative and vascular disease in the secondary prevention of cognitive decline

Neural Regeneration Research 2021年第8期16卷 1490-1499页

作者： Morgan J.Schaeffer Leona Chan philip a.barber Department of Clinical Neurosciences University of CalgaryCalgaryABCanada

Structural brain changes indicative of dementia occur up to 20 years before the onset of clinical symptoms. Efforts to modify the disease process after the onset of cognitive symptoms have been unsuccessful in recent years. Thus, future trials must begin during the preclinical phases of the disease before symptom onset. Age related cognitive decline is often the result of two coexisting brain pathologies: Alzheimer's disease(amyloid, tau, and neurodegeneration) and vascular disease. This review article highlights some of the common neuroimaging techniques used to visualize the accumulation of neurodegenerative and vascular pathologies during the preclinical stages of dementia such as structural magnetic resonance imaging, positron emission tomography, and white matter hyperintensities. We also describe some emerging neuroimaging techniques such as arterial spin labeling, diffusion tensor imaging, and quantitative susceptibility mapping. Recent literature suggests that structural imaging may be the most sensitive and cost-effective marker to detect cognitive decline, while molecular positron emission tomography is primarily useful for detecting disease specific pathology later in the disease process. Currently, the presence of vascular disease on magnetic resonance imaging provides a potential target for optimizing vascular risk reduction strategies, and the presence of vascular disease may be useful when combined with molecular and metabolic markers of neurodegeneration for identifying the risk of cognitive impairment.

关键词： amyloid arterial spin labeling cognitive decline dementia imaging magnetic resonance imaging positron emission tomography quantitative susceptibility mapping tau vascular disease white matter hyperintensities

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Corneal and intraocular pressure changes associated to the circadian rhythms:a narrative review

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1921-1928页

作者： Laura.barberán-Bernardos MiguelÁngel Ariza-Gracia David P Piñero Department of Optics Pharmacology and AnatomyUniversity of AlicanteSan Vicente del Raspeig 03690AlicanteSpain ARTORG Center for Biomedical Engineering Research University of BernBern 3008Switzerland Department of Ophthalmology(IMQO-Oftalmar) Vithas Medimar International HospitalAlicante 03016Spain

AIM:To synthesize the current body of research regarding the diurnal variations in intraocular pressure(IOP)and corneal biomechanical and morphological parameters,highlighting their significance in various eye ***:A comprehensive review of studies on the diurnal variations of IOP and corneal parameters was *** findings from various studies were assessed,including the Goldmann applanation tonometry(GAT)and non-contact *** on the variations in central corneal thickness(CCT),corneal curvature,and corneal biomechanics measured by the Ocular Response Analyzer system across different population groups was extracted and ***:In both healthy subjects and those with Fuchs dystrophy,IOP and CCT demonstrate marked diurnal *** remains the gold standard for tonometry,with the highest ***,its measurements are influenced by *** patients and those with pseudoexfoliation showed significant diurnal variations in *** biomechanical parameters,especially corneal hysteresis(CH)and the corneal resistance factor(CRF),largely remain stable throughout the day for most of eye conditions,with some ***,the corneal morphology diurnal variation,particularly curvature,yielded mixed conclusions across ***:Circadian rhythms significantly influence various corneal parameters,most notably IOP and *** studies should emphasize standardized approaches larger sample sizes,and delve deeper into less-explored areas,such as the effects of orthokeratology lenses on diurnal biomechanical shifts.

关键词： circadian rhythms intraocular pressure corneal thickness corneal biomechanics corneal curvature

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Arbuscular mycorrhizal fungi are necessary for the induced response to herbivores by Cucumis sativus

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Journal of Plant Ecology 2013年第2期6卷 171-176页

作者： Nicholas a.barber Department of Biological Sciences Northern Illinois UniversityDeKalbIL 60115USA

Aims Although ecological interactions are often conceptualized and stud-ied in a pairwise framework,ecologists recognize that the outcomes of these interactions are influenced by other members of the ***(i)between plants and insect herbivores and(I)between plants and mycorrhizal fungi are ubiquitous in terrestrial ecosystems and may be linked via common host *** studies suggest that colonization by arbuscular mycorrhizal fungi(AMF)can modifty plants'induced responses to herbivore attack,but these indirect effects of fungal symbionts are poorly understood.I investigated the role of AMF in induced plant response to a gen-eralist ***|manipulated AMF status and herbivory in Cucumis sativus L.(cucumber,Cucurbitaceae)in a greenhouse to investigate induced responses in the presence and absence of the mycorrhi-zal fungus Glomus intraradices(Glomeraceae).Spodoptera exigua Habner(Noctuidae)were used to manipulate prior damage and later as assay caterpillars.I also measured *** and her-bivory effects on plant N and effects on plant *** tant Findings AMF status affected the induced response of ***,underscor-ing the importance of incorporating the roles of plant symbionts into plant defense *** caterpillars ate significantly more leaf tissue only on mycorrhizal plants that had experienced prior *** more consumption,biomass change in these cat-erpillars did not differ from those feeding on plants with other treat-ment *** N content was reduced by *** but unaffected by herbivory treatments,suggesting that the observed differences in assay caterpillar feeding were due to changes in defensive chemistry that depended on AMF.

关键词： aboveground-belowground cucurbitacin induced defense mutualist resistance trait-mediated indirect effect

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Plant responses to arbuscular mycorrhizae under elevated temperature and drought

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Journal of Plant Ecology 2017年第4期10卷 692-701页

作者： Phyllis H.Pischl Nicholas a.barber Department of Biological Sciences Northern Illinois UniversityDeKalbIL 60115USA Institute for the Study of the Environment Sustainabilityand EnergyNorthern Illinois UniversityDeKalbIL 60115USA

Aims Climate change is predicted to cause both increased temperatures and changes in precipitation,leading to more severe droughts in some *** these changes will affect plant growth may depend in part on biotic *** vascular plants form symbiotic rela-tionships with arbuscular mycorrhizal fungi(AMF),root symbionts that provide soil nutrients to plants in exchange for carbohydrates,which may reduce the effects of environmental stresses on *** investigated if AMF modified temperature and drought effects on plant growth,fitness and defenses against *** We manipulated AMF presence,temperature and water availability on bell pepper plants(Capsicum annuum L.)in a field setting to measure plant growth and fitness *** a growth chamber experiment,we also investigated if AMF influenced insect herbi-vores feeding on plants at elevated *** findings Drought consistently reduced plant growth,and AMF did not change drought ***,with sufficient water,AMF tended to benefit plant growth and flower production(but not fruit production)compared to non-mycorrhizal *** the growth chamber,temperature and AMF influenced plant protein and phos-phorus contents,but not defensive chemistry or herbivore ***,AMF may ameliorate the effects of temperature stress due to climate change on plants by increasing growth and nutrient content,but these effects do not extend to the constitutive herbivory defenses examined here.

关键词： aboveground-belowground arbuscular mycorrhizal fungi climate change drought herbivore indirect effects

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How do belowground organisms influence plant-pollinator interactions?

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Journal of Plant Ecology 2015年第1期8卷 1-11页

作者： Nicholas a.barber Nicole L.Soper Gorden Department of Biological Sciences Northern Illinois UniversityDeKalbIL 60115USA Institute for the Study of the Environment Sustainabilityand EnergyNorthern Illinois UniversityDeKalbIL 60115USA Department of Biology University of Minnesota DuluthDuluthMN 55812USA

Aims The majority of angiosperms are pollinated by animals,and this interaction is of enormous importance in both agricultural and natural *** behavior is influenced by plants’floral traits,and these traits may be modified by interactions with other community *** recent years,knowledge of ecological linkages between above-and belowground organ-isms has grown *** communities are extremely diverse,and when their interactions with plants influence floral characteristics,they have the potential to alter pollinator attrac-tion and visitation,but plant-pollinator interactions have been neglected in studies of the direct and indirect effects of soil organism-root ***,we review these belowground interactions,focusing on the effects of nitrogen-fixing bacteria,arbuscular mycorrhizal fungi and root-feeding herbivores,and their effects on floral traits and ***,we identify gaps in our knowledge of these indirect effects and recommend promising directions and topics that should be addressed by future *** Findings Belowground organisms can influence a wide variety of floral traits that are important mediators of pollinator attraction,including the number and size of flowers and nectar and pollen *** traits that are known to influence pollinators in some plant species,such as floral volatiles,color and nectar composition,have rarely or never been examined in the context of belowground plant *** clear effects on flowers,relatively few studies have measured pollinator responses to belowground *** these indirect effects have been studied,both arbuscular mycorrhi-zal fungi and root herbivores were found to shift pollinator visitation *** on the interaction,these changes may either increase or decrease pollinator ***,we discuss future directions for ecological studies that will more fully integrate below-ground ecology with pollinat

关键词： aboveground-belowground pollinator mycorrhizae herbivore floral traits indirect effects

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不锈钢薄管折弯成型与回弹有限元模拟分析

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机械制造与自动化 2024年第3期53卷 155-157,180页

作者：褚艺光周圣何统统王丙旭 GARY barber 杭州佐帕斯工业有限公司浙江杭州310018 浙江理工大学机械与自动控制学院浙江杭州310018 奥克兰大学汽车摩擦学中心美国罗彻斯特48309

基于Simufact Forming软件建立不锈钢薄管折弯成型的有限元仿真模型,模拟薄管折弯成型过程并分析接触面摩擦因数和折弯速度对薄管折弯后回弹程度的影响。结果表明:随着薄管折弯角度的不断增大,折弯区域的等效应力逐渐增大,局部高应力区... 详细信息

基于Simufact Forming软件建立不锈钢薄管折弯成型的有限元仿真模型,模拟薄管折弯成型过程并分析接触面摩擦因数和折弯速度对薄管折弯后回弹程度的影响。结果表明:随着薄管折弯角度的不断增大,折弯区域的等效应力逐渐增大,局部高应力区域增大,外侧壁厚逐渐减小,内侧壁厚逐渐增大;薄管折弯后回弹量随摩擦因数的增大或折弯速度的减小呈现先增大后减小的趋势;当摩擦因数为0.2或折弯速度为2 s内190°时,薄管的回弹量最大。该结果能够为薄管折弯成型模拟仿真和回弹量预测提供一定的参考。

关键词：不锈钢薄管折弯成型回弹有限元模型模拟分析

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Diabetic retinopathy: recent advances towards understanding neurodegeneration and vision loss

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Science China(Life Sciences) 2015年第6期58卷 541-549页

作者： barber Alistair J. Penn State Hershey Eye Center Penn State Hershey College of Medicine Milton S. Hershey Medical Center

Diabetic retinopathy （DR） is one of the most common retinal diseases world-wide. It has a complex pathology that involves the vasculature of the inner retina and breakdown of the blood-retinal barrier. Extensive research has determined that DR is not only a vascular disease but also has a neurodegenerative component and that essentially all types of ceils in the retina are affected, leading to chronic loss of visual function. A great deal of work using animal models of DR has established the loss of neurons and pathology of other cell types, including supporting glial cells. There has also been an increased emphasis on measuring retinal function in the models, as well as further validation and extension of the animal studies by clinical and translational research. This article will attempt to summarize the more recent developments in research towards understanding the complexities of retinal neurodegeneration and functional vision loss in DR.

关键词： retina diabetes neurodegeneration visual function vascular function apoptosis synapse dendrite

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Astaxanthin Accumulation in the Green Alga Haematococcus pluvialis： Effects of Cultivation Parameters

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Journal of Integrative Plant Biology 2007年第4期49卷 447-451页

作者： Ping He James Duncan James barber Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Division of Molecular Biosciences Imperial College London London SW7 2AY UK Graduate School of Beijing Forestry University Beijing 100083 China

The green alga, Haematococcus pluvlalis Flotow is used as a source of the ketocarotenoid astaxanthin for application in fish aquaculture, pharmaceutical and cosmetic industries. Ceils of the green alga were induced by the application of different light and starvation conditions to evaluate the effect in astaxanthin accumulate. The conditions used for the Induction were high light intensity （170 μmol·m^-2·s^-1）, iron starvation, sulfur starvation and phosphate starvation. The results show that stresses applied in culture, which interfere with cell division, trigger the accumulation of astaxanthin. Notably, sulfur starvation results in a massive accumulation of this commercially important carotenoid.

关键词： astaxanthin Haematococcus pluvialis iron light phosphate stress sulfur.

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Response of grease film at low speeds under pure rolling reciprocating motion

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Friction 2020年第1期8卷 115-135页

作者： Yiming HAN Jing WANG Shanshan WANG Qian ZOU Gary barber School of Mechanical and Automotive Engineering Qingdao University of TechnologyHuangdao CampusQingdao 266520China School of Engineering and Computer Science Oakland UniversityRochesterMI 48309USA

Using an optical interferometric technique,the grease film distribution under a pure rolling reciprocating motion is observed on a ball‐disk test rig,to explore the transient response of grease,which is expected to fill the contact with thickener fiber and run for a long time under steady‐state *** is found that the reciprocating motion reduces the accumulation of the thickener fiber gradually with *** maximum film thickness forms around the stroke *** 1,000 working cycles,very severe starvation occurs so that either the central or minimum film thickness becomes nearly constant over one working ***,the life of grease lubrication under a transient condition is far below that under steady‐state ***,it is also found that by selecting a smaller stroke length,the thickener fiber spreads out in the contact instead of being removed from the contact at the 1,000th working *** increasing the maximum entraining speed of the reciprocating motion to a certain value,during which the thickener fiber is not expected to accumulate under a steady‐state condition,severe starvation occurs very quickly,causing surface damage.

关键词： grease lubrication reciprocation pure rolling grease starvation thickener fiber

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An analytical validation for the attenuation of lateral propagating light in sea ice

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Acta Oceanologica Sinica 2015年第3期34卷 1-8页

作者： ZHAO Jinping LI Tao EHN Jens barber David Physical Oceanography Laboratory Ocean University of China Centre for Earth Observation Science University of Manitoba

The attenuation of lateral propagating light （LPL） in sea ice was measured using an artificial light source in the Canadian Arctic during the 2007/2008 winter. The apparent attenuation coefficientμ（λ）for lateral prop-agating light was obtained from the measured logarithmic relative variation rate. In this study an analytical solution based on the strict optical theories is developed to validate the measured result. There is a good consistency between theoretical solution and measured data, by which a quite simple but very rigorous relationship among the light source, measurement geometry, and measured irradiance is established. The attenuation coefficients acquired by measurement and theory are the diffusion attenuation as an apparent optical property of ice, independent of the light source and shining condition. The attenuation ability of sea ice should be caused by the microstructure of sea ice, such as crystal size, ice density, brine volume, air inclusion, etc. It also includes the leak from both interfaces by directional scattering. It is verified that the measuring approach is operational and accurate to measure the attenuation of the LPL. The solution from this study did not tell the connection among the extinction and the inclusions of sea ice theoretically be-cause of insufficient understanding.

关键词： Arctic,sea ice lateral propagating light optical attenuation coefficient artificial light analytical solution

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