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Vertical physicochemical parameter distributions and health risk assessment for trace metals in water columns in eastern Lake Tanganyika, Tanzania

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Journal of Oceanology and Limnology 2019年第1期37卷 134-145页

作者： sHEN Qiushi ZHANG Lu Ismael aaron KIMIREI WANG Zhaode GAO Qun CHEN shuang YU Cheng state Key Laboratory of Lake science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences sino-Africa Joint Research Center Chinese Academy of Sciences Tanzania Fisheries Research Institute-Kigoma Centre school of Environmental science and Technology Suzhou University of Science and Technology

The vertical distributions of trace metals and physicochemical parameters in water columns in Kigoma Bay and Kungwe Bay in eastern Lake Tanganyika, Tanzania, were studied. The Al, Ba, Ca, Co,K, Mg, Mn, Mo, Na, sn, sr, and V concentrations were low and varied very little with depth. The toxic heavy metal(As, Cr, Cu, Ni, Pb, and Zn) concentrations were relatively high in the surface water, and the Cu, Ni, Pb, and Zn concentrations decreased with depth. Principal component and cluster analyses indicated that the metals in the lake had three main sources. Al, Ba, Ca, Co, Cu, Cr, Mn, sr, sn, and V were found to be geogenic; As, Cr, Cu, Mo, Ni, Pb, sn and Zn anthropogenic; and As, Ca, Co, Mg, and Na *** health risk assessments were performed, and it was found that trace metals in the water at most of the sampling sites would cause no potential adverse ef fects or non-carcinogenic health risks through dermal contact or ingestion. However, trace metals in surface water in Kungwe Bay could have certain adverse ef fects on human health through the ingestion pathway(the total hazard quotient for ingestion(ΣHQi ng)was 1.75(a value >1 was de?ned as possibly indicating adverse ef fects). The Pb HQi ng for surface water in Kungwe Bay was 1.50 and contributed >80% of the ΣHQ_(ing_, implying that Pb pollution is a water quality and safety problem that needs to be carefully monitored and the potential sources identi?ed.

关键词： trace metal heavy metal risk assessment water column Lake Tanganyika

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Application of Hausdorff fractal derivative to the determination of the vertical sediment concentration distribution

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International Journal of sediment Research 2023年第1期38卷 12-23页

作者： Hongguang sun shiqian Nie aaron I.Packman Yong Zhang Dong Chen Chengpeng Lu Chunmiao Zheng state Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Mechanics and Materials Hohai University College of Mathematics and systems science Shandong University of Science and Technology Department of Civil and Environmental Engineering Northwestern University Department of Geological sciences University of Alabama Institute of Geographic sciences and Natural Resources Research Chinese Academy of sciences College of Hydrology and Water Resources Hohai University school of Environmental science and Engineering Southern University of Science and Technology

The Rouse formula and its variants have been widely used to calculate the steady-state vertical concentration distribution for suspended sediment in steady sediment-laden flows, where the diffusive flux is assumed to be Fickian. Turbulent flow, however, exhibits fractal properties, leading to non-Fickian diffusive flux for sediment particles. To characterize non-Fickian dynamics of suspended sediment, the current study proposes a Hausdorff fractal derivative based advection-dispersion equation(HADE)model, where the Fickian diffusive flux in the Rouse model is replaced by a fractal derivative re-scaled using a constant diffusivity. The order of the Hausdorff fractal derivative is designed to characterize the influence of the multi-fractal turbulence structure on sediment diffusion. Applications show that the HADE model, with the analytical solution expressed using a stretched exponential function, can accurately describe the observed vertical concentration profiles for suspended sediment with different *** improvement well captures the non-exponential decay of the vertical sediment concentration in turbulent flow. Further analyses of measured sediment concentration profiles reveal that the Hausdorff fractal order decreases with the Rouse parameter, which describes the stronger impact of turbulent flow and a more uniform sediment concentration profile for smaller particles. Model comparisons also show that the HADE model provides better performance in describing the sediment concentration profiles than the improved Rouse formula and the standard fractional derivative advection-dispersion equation(FADE), which either under-or over-estimates vertical displacement of sediment particles, likely due to coherent turbulent structures.

关键词： Anomalous diffusion Hausdorff fractal derivative Vertical concentration distribution suspended sediment Metric transform

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Incoherent excess noise spectrally encodes broadband light sources

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Light(science & Applications) 2020年第1期9卷 358-366页

作者： aaron M.Kho Tingwei Zhang Jun Zhu Conrad W.Merkle Vivek J.srinivasan Department of Biomedical Engineering University of California DavisDavisCA 95616USA Department of Ophthalmology and Vision science University of California Davis School of MedicineSacramentoCA 95817USA

Across optics and photonics,excess intensity noise is often considered a ***,we show that excess noise in broadband supercontinuum and superluminescent diode light sources encodes each spectral channel with unique intensity fluctuations,which actually serve a useful ***,we report that excess noise correlations can both characterize the spectral resolution of spectrometers and enable cross-calibration of their wavelengths across a broad *** to previous methods that use broadband interferometry and narrow linewidth lasers to characterize and calibrate spectrometers,our approach is simple,comprehensive,and rapid enough to be deployed during spectrometer ***,we employ this approach to aid alignment and reduce the depth-dependent degradation of the sensitivity and axial resolution in a spectrometer-based optical coherence tomography(OCT)system,revealing a new outer retinal ***,we achieve a pixel-to-pixel correspondence between two otherwise disparate spectrometers,enabling a robust comparison of their respective ***,excess intensity noise has useful applications in optics and photonics.

关键词： noise spectral optics

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Parvalbumin neuroplasticity compensates for somatostatin impairment, maintaining cognitive function in Alzheimer’s disease

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Translational Neurodegeneration 2022年第1期11卷 566-587页

作者： Christopher Daniel Morrone aaron Yenhsin Lai Jossana Bishay Mary Elizabeth Hill JoAnne McLaurin Biological sciences Sunnybrook Research InstituteTorontoON M4N 3M5Canada Department of Laboratory Medicine and Pathobiology Temerty Faculty of MedicineUniversity of TorontoTorontoON M5S 1A8Canada

Background: Patient-to-patient variability in the degree to which β-amyloid, tau and neurodegeneration impact cognitive decline in Alzheimer’s disease (AD) complicates disease modeling and treatment. However, the underlying mechanisms leading to cognitive resilience are not resolved. We hypothesize that the variability in cognitive function and loss relates to neuronal resilience of the hippocampal GABAergic network. Methods: We compared TgF344-AD and non-transgenic littermate rats at 9, 12, and 15 months of age. Neurons, β-amyloid plaques and tau inclusions were quantified in hippocampus and entorhinal cortex. somatostatin (ssT) and parvalbumin (PVB) interneurons were traced to examine hippocampal neuroplasticity and cognition was tested in the Barnes maze. Results: The 9-month-old TgF344-AD rats exhibited loss of neurons in the entorhinal cortex and hippocampus. Hippocampal neuronal compensation was observed in 12-month TgF344-AD rats, with upregulation of GABAergic interneuronal marker. By 15 months, the TgF344-AD rats had robust loss of excitatory and inhibitory neurons. β-Amyloid and tau pathology accumulated continuously across age. ssT interneurons exhibited tau inclusions and atrophy from 9 months, whereas PVB interneurons were resilient until 15 months. The hippocampal PVB circuit underwent neuroplastic reorganization with increased dendritic length and complexity in 9- and 12-month-old TgF344- AD rats, before atrophy at 15 months. strikingly, 12-month-old TgF344-AD rats were resilient in executive function and cognitive flexibility. Cognitive resilience in TgF344-AD rats occurred as maintenance of function between 9 and 12 months of age despite progressive spatial memory deficits, and was sustained by PVB neuroplasticity. Conclusions: Our results demonstrate the inherent neuronal processes leading to cognitive maintenance, and describe a novel finding of endogenous cognitive resilience in an AD model.

关键词： Alzheimer’s disease TgF344-AD rat GABAergic interneuron Parvalbumin somatostatin Barnes maze Hippocampus Neuronal compensation Cognitive resilience

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关于加强大城市交通规划建设与管理工作的建议

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城市规划 2011年第2期35卷 15-16页

作者：马林中国城市规划学会城市交通规划学术委员会

基于对"十二五"期间我国大城市交通发展形势的认识和判断,提出了未来五年要坚持"和谐高效、服务民生、节约资源、科学决策"的发展理念,加快实施五项发展策略。为了推进大城市交通发展模式的转变,构建以公共交通为主体的城市综合交通体系... 详细信息

基于对"十二五"期间我国大城市交通发展形势的认识和判断,提出了未来五年要坚持"和谐高效、服务民生、节约资源、科学决策"的发展理念,加快实施五项发展策略。为了推进大城市交通发展模式的转变,构建以公共交通为主体的城市综合交通体系,促进绿色、节能、低碳交通方式的发展,就加强大城市交通规划、建设与管理工作提出了具体建议。

关键词：大城市交通规划与建设交通需求管理发展策略

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Virus-Encoded MicroRNAs Reveal How Ranavirus Interacts with Amphibian Immune Defense

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Journal of Biomedical science and Engineering 2024年第10期17卷 179-184页

作者： aaron Yang Horace Mann school Bronx NY USA

Ranaviruses are harmful viruses that infect amphibians, fish, and reptiles, and have caused particularly devastating declines in amphibian populations. One particular type of ranavirus, called Frog Virus 3 (FV3), has been extensively studied due to its prevalence and impact on amphibians. Previous research has primarily focused on the virus’s genes, but little attention has been given to the non-coding regions of its genome. This article reviews recent studies that reveal the ability of ranaviruses, including FV3, to encode microRNA (miRNA), a type of regulatory RNA. These viral miRNAs play a crucial role in suppressing frog immune genes, modulating the virus-host interaction, and promoting viral infection. Understanding how ranaviruses use miRNAs to control disease progression is essential for addressing the health threat they pose to wildlife and ecosystems.

关键词： Ranaviruses Amphibians Virus-Encoded MicroRNA Frog Virus 3 Virus-Host Interaction

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Inflammation and intracranial aneurysms:mechanisms of initiation,growth,and rupture

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 68-76页

作者： Peter s.Amenta Edison Valle aaron s.Dumont Ricky Medel Department of Neurosurgery Tulane University School of MedicineNew OrleansLA 70112USA

Outcomes following aneurysmal subarachnoid hemorrhage remain poor in many patients,despite advances in microsurgical and endovascular ***,considerable effort has been placed in determining the mechanisms of aneurysm formation,growth,and *** environmental and genetic factors are implicated as key components in the aneurysm ***,sufficient evidence exists to incriminate the inflammatory response as the common pathway leading to aneurysm generation and *** to this model is the interaction between the vessel wall and inflammatory *** of the endothelium and vascular smooth muscle cells(VsMCs)promotes a chronic pathological inflammatory response that progressively weakens the vessel *** review the literature pertaining to the cellular and chemical mechanisms of inflammation that contribute to aneurysm *** stress and alterations in blood flow are discussed regarding their role in promoting chronic *** cell and VsMC dysfunction are examined concerning vascular *** contribution of inflammatory cytokines,especially tumor necrosis factor‑α is *** cell infiltration,particularly macrophage‑mediated deterioration of vascular integrity,is *** discuss the inflammation as a means to determine aneurysms at greatest risk of ***,future therapeutic implications of pharmacologic modulation of the inflammation are discussed.

关键词： Aneurysm endothelium inflammation subarachnoid hemorrhage vascular smooth muscle cells

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Reconfigurable nonlinear photonic activation function for photonic neural network based on non-volatile opto-resistive RAM switch

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Light(science & Applications) 2022年第10期11卷 2512-2522页

作者： Zefeng Xu Baoshan Tang Xiangyu Zhang Jin Feng Leong Jieming Pan sonu Hooda Evgeny Zamburg aaron Voon-Yew Thean Integrative sciences and Engineering Programme NUS Graduate SchoolNational University of SingaporeSingaporeSingapore Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore

Photonic neural network has been sought as an alternative solution to surpass the efficiency and speed bottlenecks of electronic neural *** that the integrated Mach-Zehnder Interferometer(MZI)mesh can perform vector-matrix multiplication in photonic neural network,a programmable in-situ nonlinear activation function has not been proposed to date,suppressing further advancement of photonic neural ***,we demonstrate an efficient in-situ nonlinear accelerator comprising a unique solution-processed two-dimensional(2D)Mos2 Opto-Resistive RAM switch(ORs),which exhibits tunable nonlinear resistance switching that allow us to introduce nonlinearity to the photonic neuron which overcomes the linear voltage-power relationship of typical photonic *** reconfigurable scheme enables implementation of a wide variety of nonlinear ***,we confirm its feasibility and capability for MNIsT handwritten digit recognition,achieving a high accuracy of 91.6%.Our accelerator constitutes a major step towards the realization of in-situ photonic neural network and pave the way for the integration of photonic integrated circuits(PIC).

关键词： network neural nonlinear

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Dielectric metasurfaces for complete and independent control of the optical amplitude and phase

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Light(science & Applications) 2019年第1期8卷 318-329页

作者： Adam C.Overvig sajan shrestha stephanie C.Malek Ming Lu aaron stein Changxi Zheng Nanfang Yu Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY 10027USA Center for Functional Nanomaterials Brookhaven National LaboratoryUptonNY 11973USA Department of Computer science Columbia UniversityNew YorkNY 10027USA

Metasurfaces are optically thin metamaterials that promise complete control of the wavefront of light but are primarily used to control only the phase of ***,we present an approach,simple in concept and in practice,that uses meta-atoms with a varying degree of form birefringence and rotation angles to create high-efficiency dielectric metasurfaces that control both the optical amplitude and phase at one or two *** opens up applications in computer-generated holography,allowing faithful reproduction of both the phase and amplitude of a target holographic scene without the iterative algorithms required in phase-only *** demonstrate all-dielectric metasurface holograms with independent and complete control of the amplitude and phase at up to two optical frequencies simultaneously to generate two-and three-dimensional holographic *** show that phaseamplitude metasurfaces enable a few features not attainable in phase-only holography;these include creating artifactfree two-dimensional holographic images,encoding phase and amplitude profiles separately at the object plane,encoding intensity profiles at the metasurface and object planes separately,and controlling the surface textures of three-dimensional holographic objects.

关键词： holographic phase complete

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De novo ADGRV1 variant in a patient with ictal asystole provides novel clues for increased risk of sUDEP

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Acta Epileptologica 2023年第2期6卷 118-126页

作者： Tuo Ji aaron W.Downs Luong Dorris Ning Zhong sQZ Biotechnologies WatertownMA 02472USA Morrissey College of Arts and sciences Boston CollegeChestnut HillMA 02467USA College of Medicine California Northstate UniversityElk GroveCA 95757USA Pediatric and Adolescent Medicine Residency of Mayo Clinic MNRochesterUSA Department of Neurology Kaiser Permanente Sacramento Medical CenterSacramentoCA 95825USA North Valley Comprehensive Epilepsy Program Kaiser Permanente Sacramento Medical CenterSacramentoCA 95825USA

Background Various cardiac and autonomic manifestations are frequently reported during *** the seizure-related arrhythmia,ictal tachycardia is the most common,followed by ictal bradycardia,with ictal asystole being the *** occurrence of ictal asystole may obscure the clinical presentation and delay the diagnosis,representing a life-threatening presentation of epilepsy,with an elevated risk of sudden unexpected death in epilepsy patients(sUDEP).These cardiac abnormalities are being increasingly recognized as the key to elucidating the mechanisms of *** presentation We present a 35-year-old man with a history of focal-onset seizures with impaired consciousness since his mid-20 *** developed different types of seizures for 2 years,described as tonic seizure and atonic seizure(drop attack).During such clinical events,he suffered from falls and cardiac ***,thorough cardiac electrophysiology and imaging workup failed to reveal a cardiac *** video electroencephalograph(EEG)monitoring was performed,and ictal bradycardia and ictal asystole were discovered.A cardiac pacemaker was implanted,and at 3-year follow-up,the patient did not suffer more atonic seizures,or *** tests discovered a de novo variant of Adhesion G Protein-Coupled Receptor V1(ADGRV1),which may provide a clue for the patient’s ictal asystole and the increased risk of *** Considering the important impact of ictal bradycardia and asystole on the morbidity and potential mortality of epileptic patients,it is important to simultaneously utilize EEG and electrocardiogram to confirm the *** case report highlights the link between the de novo variant of ADGRV1 and the ictal bradycardia/asystole phenotype and implicates the importance of genetic testing in adult epilepsy patients.

关键词： Ictal asystole Drug resistant epilepsy ADGRV1 sUDEP

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