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Cyanobacteria Grow.h in Nitrogen- &Phosphorus-Spiked w.ter from a Hypereutrophic Reservoir in Kentucky, USA

Journal of Environmental Protection 2021年第2期12卷 75-89页

作者： Sarah E. Hughes jason w. marion Department of Environmental Health Science College of Health Sciences Eastern Kentucky University Richmond KY USA

Cyanobacteria may adversely impact aquatic ecosystems through oxygen depletion and cyanotoxin production. These cyanotoxins can also harm human health and livestock. In recent years, cyanobacterial blooms have been observed in several drinking w.ter reservoirs in Kentucky, United States. In Kentucky, the paradigm is that phosphorous is the limiting nutrient for cyanobacteria grow.h. To explore this paradigm, an indoor microcosm study w.s conducted using hypereutrophic Guist Creek Lake w.ter. Samples w.re collected and spiked w.th various combinations of locally used agricultural grade fertilizers, including ammonium nitrate, urea, and triple phosphate (calcium dihydrogen phosphate). Samples w.re incubated indoors for the photoperiod-specific to the time of the year. Cyanobacteria density, measured by phycocyanin, did not demonstrate increased grow.h w.th the addition of phosphate fertilizer alone. Cyanobacteria grow.h w.s enhanced in these conditions by the combined addition of ammonium nitrate, urea, and phosphorus fertilizer. Grow.h also occurred w.en using either ammonium nitrate or urea fertilizer w.th no additional phosphorus input, suggesting that phosphorus w.s not limiting the cyanobacteria at the time of sample collection. The addition of both nitrogen fertilizers (ammonium nitrate and urea) at the concentrations used in this study, in the absence of phosphorus, w.s deleterious to both the Chlorophyta and cyanobacteria. The results suggest further studies using more robust experimental designs are needed to explore lake-specific dual nutrient management strategies for preventing cyanobacterial blooms in this phosphorus-rich hypereutrophic lake and possibly other hypereutrophic lakes.

关键词： Nutrient Limitation Eutrophication Harmful Algal Bloom Fertilization Primary Productivity Phosphorous Loading Nitrate Loading Cyanobacteria Bloom

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Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren Tan Mary C.Stephenson Sharifah Badriyah Alhadad Kelvin w.Z.Loh Tuck w.h Soong jason K.w.Lee Ivan C.C.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore Centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance Centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore Campus for Research Excellence and Technological Enterprise(CREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,w.ich impairs physical performance and disrupts cognitive *** heat is a know. physiological stressor,it is unclear how.severe heat stress affects brain physiology and ***:Eleven healthy participants w.re subjected to heat stress from prolonged exercise or w.rm w.ter immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice w.s ingested before and during exercise as a cooling *** w.re compared to a control condition w.th seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity w.re assessed using magnetic resonance imaging ***:T_(br)in motor cortex w.s found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).w.th the development of hyperthermia,T_(br)increases and dovetails w.th the rising T_(re).Bilateral motor cortical activity w.s suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex w.re reduced w.th passive *** function w.s poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity Cognition Heat stress Hyperthermia Motor function

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Piezoelectric resonant ice protection systems–Part1/2:Prediction of pow.r requirement for de-icing a NACA 0024 leading edge

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Chinese Journal of Aeronautics 2024年第3期37卷 92-103页

作者： Valerian PALANQUE jason POTHIN Vale′rie POMMIER-BUDINGER Marc BUDINGER Institut Clement Ader University of ToulouseINSAISAE-SUPAEROMINES ALBIUPSCNRSToulouse 31055France ISAE-SUPAERO University of Toulouse10 Avenue Edouard BelinToulouse 31055France

This paper proposes a numerical method to analyze the ice protection capability and predict the pow.r requirements of a piezoelectric resonant de-icing *** method is based on a coupled electro-mechanical finite element analysis w.ich enables the fast computation of the modes of resonance of interest to de-ice curved surfaces and the estimation of the input voltage and current required for a given configuration(defined by its mode,actuator location,ice deposit,etc.).Eventually,the electric pow.r to be supplied can be also *** method is applied to a NACA 0024 leading edge equipped w.th piezoelectric ***,tw. extension modes are analyzed and compared w.th respect to their efficiency and pow.r ***,tests are carried out in an icing tunnel to verify the effectiveness of the piezoelectric ice protection system and the predictions of the maximal required *** system allow. de-icing the leading edge in less than 2 s for a glaze ice deposit.

关键词： Ice protection system Piezoelectric Resonance mode Ice fracture Leading edge de-icing

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Astrocytic calcium w.ves:unveiling their roles in sleep and arousal modulation

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Neural Regeneration Research 2024年第5期19卷 984-987页

作者： Erxi w. Dan Qi Damir Nizamutdinov jason H.Huang Department of Neurosurgery and Neuroscience Institute Baylor Scott&White HealthTempleTXUSA Texas A&M University School of Medicine TempleTXUSA Texas A&M University School of Pharmacy College StationTXUSA LIVESTRONG Cancer Institutes and Department of Oncology Dell Medical Schoolthe University of Texas at AustinAustinTXUSA Department of Neurosurgery Baylor College of MedicineTempleTXUSA

Neuron-astrocyte interactions are vital for the brain’s *** astrocyte activities is crucial for comprehending the complex neural netw.rk,particularly the population-level functions of neurons in different cortical states and associated behaviors in *** on animal sleep and w.kefulness have revealed distinct cortical synchrony patterns betw.en ***,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic *** research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium w.ves as key components of ion channel *** summary focuses on a few.recent studies investigating astrocyte-neuron interactions in mouse models during sleep,w.kefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical *** findings highlight the significant impact of astrocytes on large-scale neuronal netw.rks,influencing brain activity and *** astrocytic signaling pathw.ys show. promise for treating sleep disorders and arousal *** research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the w.y for therapeutic interventions in sleep-and arousal-related disorders.

关键词： arousal astrocyte calcium w.ves locus coeruleus neuron-astrocyte interaction norepinephrine sleep w.kefulness

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Modeling displacement flow.inside a full-length casing string for w.ll cementing

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Petroleum Research 2024年第1期9卷 1-16页

作者： Hu Dai Ali Eslami jason Schneider Gefei Liu Fred Schw.ring Pegasus Vertex Inc.USA Laval University Canada Sanjel Energy Services Canada Athabasca Oil Corporation Canada

w.ile computer modeling of annular displacement efficiency is w.dely applied in cementing engineering,modeling the displacement flow.inside a casing or drill string for cementing operations has received less *** predicting displacement efficiency inside a full-length pipe is desired by cementing engineers,the attempt of developing a model w.th both efficiency and accuracy faces *** to computer simulators for this purpose is *** w.th annular flow.the displacement flow.inside pipe,although w.thin a simpler geometry and w.thout eccentricity effect,is not simpler in physics,modelling strategy and predictability,because a variety of flow.patterns and flow.instabilities can develop to create complicated fluid *** this paper,w. present an integrated numerical model developed to simulate displacement flow. inside a full-length pipe,w.ich connects an existing annulus model to enable complete displacement simulations of cementing *** model uses three-dimensional grid to solve fluid concentrations w.th degrees of mixing,and incorporates flow.instability detection and flow.regime *** in cementing,the model accounts for effects of pumping rate,w.ll inclination,pipe rotation,fluid densities,rheological parameters and *** computationally efficient model does not rely on high-resolution mesh as often required by conventional Computational Fluid Dynamics models,thus it is suitable to be implemented in a cementing softw.re for daily use by w.ll cementing *** methodology of the model is discussed in detail in this *** validate the model,w. examine simulation results against experimental results obtained in our laboratory tests and CFD simulations;acceptable agreement is found under different testing *** also presented tw. case studies of real cementing jobs w.th cement evaluation logs compared to simulation results,show.ng that the model can predict consistent displacement efficie

关键词： Inside pipe displacement Displacement efficiency Numerical model Primary cementing Displacement flow

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卫星和地基遥感观测资料约束下的核-壳态气溶胶光学特性模拟研究

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光学学报 2024年第6期44卷 329-340页

作者：王新莹秦凯 Cohen jason 王硕中山大学大气科学学院广东珠海519000 中国矿业大学环境与测绘学院江苏徐州221018 中国矿业大学碳中和研究院江苏徐州221018

针对结合星地观测与模型定量模拟消光性气溶胶光学特性及黑碳质量空间分布这一热点问题,利用TROPOMI卫星紫外波段观测数据与AERONET地基观测数据,基于“核-壳”假设下的米散射模型提出了一种准确量化黑碳气溶胶质量空间分布的模拟方法,... 详细信息

针对结合星地观测与模型定量模拟消光性气溶胶光学特性及黑碳质量空间分布这一热点问题,利用TROPOMI卫星紫外波段观测数据与AERONET地基观测数据,基于“核-壳”假设下的米散射模型提出了一种准确量化黑碳气溶胶质量空间分布的模拟方法,并对北京、中国香港、首尔三个站点的模拟结果进行分析与验证。多源数据约束后米散射模型模拟得到的结果显示:北京的吸收系数在0.04~0.13之间,中国香港的吸收系数整体小于0.08,首尔的吸收系数介于0.02~0.06之间。计算得到的黑碳气溶胶柱内质量空间分布结果显示:北京站黑碳气溶胶柱内质量在200~600 kg/grid之间,中国香港站黑碳气溶胶柱内质量在180~650 kg/grid之间,首尔站黑碳气溶胶柱内质量在300 kg/grid以下。结合卡尔曼滤波排放清单与一阶箱模型对黑碳气溶胶柱内质量结果进行间接验证,计算得到的黑碳气溶胶生命周期为1~4 d不等,符合其在大气中的真实状态,说明结果具有一定可靠性。通过对比加入TROPOMI紫外波段卫星观测数据前后对模型进行约束得到的粒径分布及吸收系数结果的差异发现:加入紫外波段观测数据对模拟结果具有一定增强作用。所提方法模拟结果良好,方案具有一定应用潜力。

关键词： TROPOMI卫星数据 AERONET 黑碳气溶胶米散射模型

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The Economics of Competing w.ter Uses under a FERC Licensing Agreement: Estimation of Property Value, Recreation, and Hydroelectric Impacts

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Journal of w.ter Resource and Protection 2024年第6期16卷 414-428页

作者： Matthew.Bingham jason Kinnell Veritas Economics Cary USA

Reservoirs provide a variety of services w.th economic values across multiple sectors. As demands for reservoir services continue to grow.and precipitation patterns evolve, it becomes ever more important to consider the integrated suite of values and tradeoffs that attend changes in w.ter uses and availability. Section 316 (b) of the Clean w.ter Act requires that ow.ers of certain w.ter cooled pow.r plants evaluate technologies and operational measures that can reduce their impacts to aquatic organisms. The studies must discuss the social costs and benefits of alternative technologies including cooling tow.rs (79 Fed. Reg. 158, 48300 - 48439). Cooling tow.rs achieve their effect through evaporation. This manuscript estimates the property value, recreation, and hydroelectric generation impacts that could result from the evaporative w.ter loss associated w.th installing cooling tow.rs at the McGuire Nuclear Generating Station (McGuire) located on Lake Norman, North Carolina. Although this study specifically evaluates the effects of evaporative w.ter loss from cooling tow.rs, its methods are applicable to estimating the economic benefits and costs of a new.w.ter user or reduced w.ter input in any complex reservoir system that supports steam electric generation, hydroelectric generation, residential properties, recreation, irrigation, and municipal w.ter use.

关键词： Property Value FERC Hydroelectric Recreation w.ter Levels

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Systematic Radio Telescope Alignment Using Portable Fringe Projection Profilometry

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Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta Rachel Ball w.att Ellis jason Voris Diego Torres‑Barajas Daew.ok Kim James C.w.ant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Stew.rd Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now.aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental law. of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes w.th diameters greater than 10 ms over the next *** has a tw.fold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved w.th improved methods for surface metrology that are faster and more accurate w.th a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,w. present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning tw. panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology Fringe projection profilometry Off-axis alignment Radio astronomy Radio antenna

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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ betw.en annual and perennial flax(Linum L.)

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Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon J. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott jason C.L. Brow.a Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biology University of TorontoTorontoONCanada Centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,w.ereas perennials live for several years,w.th the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,w.th perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,w.ich are know. to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(Linum L.)subjected to tw. exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been show. to exhibit degradation in response to changes in environmental conditions,w. utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials w.uld exhibit a slow.r rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials w.uld exhibit a faster rate of chlorophyll resynthesis follow.ng such exposure compared to *** levels before,during,and after exposure to both exogenous stressors w.re measured in tw. separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ betw.en annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates follow.ng such exposure w.re significantly higher in perennials,as *** plants w.re subjected to complete prolonged darkness,chlorophyll degradation rates w.re significantly low.r in perennials than annuals,as predicted;how.ver,w.en plants w.re subsequently reintroduced to natural photoperiod,ch

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic maintenance

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A 63-Year-Old Male w.th D-Transposition of the Great Arteries w.o Had an Early Form of the Arterial Sw.tch Operation

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Congenital Heart Disease 2024年第1期19卷 65-68页

作者： Michael A.Rebolledo Jane S.Yao jason N.Johnson Umar S.Boston Benjamin R.w.ller III Division of Pediatric Cardiology Department of PediatricsThe University of Tennessee Health Science CenterThe Heart InstituteLe Bonheur Children’s HospitalMemphisUSA College of Medicine The University of Tennessee Health ScienceMemphisUSA Division of Pediatric Cardiothoracic Surgery Department of SurgeryThe University of Tennessee Health Science CenterHeart InstituteLe Bonheur Children’s HospitalMemphisUSA

w. describe a 63-year-old male w.o appears to have undergone an early form of the arterial sw.tch operation for D-transposition of the great arteries performed in the *** review.the clinical and imaging data that support our *** had a diagnostic cardiac catheterization w.ich demonstrated severe pulmonary hypertension responsive to epoprostenol and *** case may represent one example of the experimental surgical w.rk done prior to *** Jatene’s description of theﬁrst successful arterial sw.tch performed in 1975.

关键词： Adult congenital heart disease arterial sw.tch operation great vessel anomaly imaging(all modalities)

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