The Experts below are selected from a list of 14229 Experts worldwide ranked by ideXlab platform
Bjorn H Falkenburger - One of the best experts on this subject based on the ideXlab platform.
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accumulation and clearance of α synuclein Aggregates demonstrated by time lapse imaging
Journal of Neurochemistry, 2008Co-Authors: Felipe Opazo, Antje Krenz, Stephan Heermann, Jorg B Schulz, Bjorn H FalkenburgerAbstract:Aggregates of α-synuclein are the pathological hallmark of sporadic Parkinson’s disease (PD), and mutations in the α-synuclein gene underlie familial forms of the disease. To characterize the formation of α-synuclein Aggregates in living cells, we developed a new strategy to visualize α-synuclein by fluorescence microscopy: α-synuclein was tagged with a six amino acid PDZ binding motif and co-expressed with the corresponding PDZ domain fused to enhanced green fluorescent protein (EGFP). In contrast to the traditional approach of α-synuclein-EGFP fusion proteins, this technique provided several-fold higher sensitivity; this allowed us to compare α-synuclein variants and perform time-lapse imaging. A C-terminally truncated α-synuclein variant showed the highest prevalence of Aggregates and toxicity, consistent with stabilization of the α-synuclein monomer by its C-terminus. Time-lapse imaging illustrated how cells form and accumulate Aggregates of α-synuclein. A substantial number of cells also reduced their Aggregate Load, primarily through formation of an aggresome, which could itself be cleared from the cell. The molecular chaperone Hsp70 not only prevented the formation of Aggregates, but also increased their reduction and clearance, underlining the therapeutic potential of similar strategies. In contrast to earlier assumptions build-up, reduction and clearance of α-synuclein aggregation thus appear a highly dynamic process.
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Accumulation and clearance of α‐synuclein Aggregates demonstrated by time‐lapse imaging
Journal of Neurochemistry, 2008Co-Authors: Felipe Opazo, Antje Krenz, Stephan Heermann, Jorg B Schulz, Bjorn H FalkenburgerAbstract:Aggregates of α-synuclein are the pathological hallmark of sporadic Parkinson’s disease (PD), and mutations in the α-synuclein gene underlie familial forms of the disease. To characterize the formation of α-synuclein Aggregates in living cells, we developed a new strategy to visualize α-synuclein by fluorescence microscopy: α-synuclein was tagged with a six amino acid PDZ binding motif and co-expressed with the corresponding PDZ domain fused to enhanced green fluorescent protein (EGFP). In contrast to the traditional approach of α-synuclein-EGFP fusion proteins, this technique provided several-fold higher sensitivity; this allowed us to compare α-synuclein variants and perform time-lapse imaging. A C-terminally truncated α-synuclein variant showed the highest prevalence of Aggregates and toxicity, consistent with stabilization of the α-synuclein monomer by its C-terminus. Time-lapse imaging illustrated how cells form and accumulate Aggregates of α-synuclein. A substantial number of cells also reduced their Aggregate Load, primarily through formation of an aggresome, which could itself be cleared from the cell. The molecular chaperone Hsp70 not only prevented the formation of Aggregates, but also increased their reduction and clearance, underlining the therapeutic potential of similar strategies. In contrast to earlier assumptions build-up, reduction and clearance of α-synuclein aggregation thus appear a highly dynamic process.
Felipe Opazo - One of the best experts on this subject based on the ideXlab platform.
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accumulation and clearance of α synuclein Aggregates demonstrated by time lapse imaging
Journal of Neurochemistry, 2008Co-Authors: Felipe Opazo, Antje Krenz, Stephan Heermann, Jorg B Schulz, Bjorn H FalkenburgerAbstract:Aggregates of α-synuclein are the pathological hallmark of sporadic Parkinson’s disease (PD), and mutations in the α-synuclein gene underlie familial forms of the disease. To characterize the formation of α-synuclein Aggregates in living cells, we developed a new strategy to visualize α-synuclein by fluorescence microscopy: α-synuclein was tagged with a six amino acid PDZ binding motif and co-expressed with the corresponding PDZ domain fused to enhanced green fluorescent protein (EGFP). In contrast to the traditional approach of α-synuclein-EGFP fusion proteins, this technique provided several-fold higher sensitivity; this allowed us to compare α-synuclein variants and perform time-lapse imaging. A C-terminally truncated α-synuclein variant showed the highest prevalence of Aggregates and toxicity, consistent with stabilization of the α-synuclein monomer by its C-terminus. Time-lapse imaging illustrated how cells form and accumulate Aggregates of α-synuclein. A substantial number of cells also reduced their Aggregate Load, primarily through formation of an aggresome, which could itself be cleared from the cell. The molecular chaperone Hsp70 not only prevented the formation of Aggregates, but also increased their reduction and clearance, underlining the therapeutic potential of similar strategies. In contrast to earlier assumptions build-up, reduction and clearance of α-synuclein aggregation thus appear a highly dynamic process.
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Accumulation and clearance of α‐synuclein Aggregates demonstrated by time‐lapse imaging
Journal of Neurochemistry, 2008Co-Authors: Felipe Opazo, Antje Krenz, Stephan Heermann, Jorg B Schulz, Bjorn H FalkenburgerAbstract:Aggregates of α-synuclein are the pathological hallmark of sporadic Parkinson’s disease (PD), and mutations in the α-synuclein gene underlie familial forms of the disease. To characterize the formation of α-synuclein Aggregates in living cells, we developed a new strategy to visualize α-synuclein by fluorescence microscopy: α-synuclein was tagged with a six amino acid PDZ binding motif and co-expressed with the corresponding PDZ domain fused to enhanced green fluorescent protein (EGFP). In contrast to the traditional approach of α-synuclein-EGFP fusion proteins, this technique provided several-fold higher sensitivity; this allowed us to compare α-synuclein variants and perform time-lapse imaging. A C-terminally truncated α-synuclein variant showed the highest prevalence of Aggregates and toxicity, consistent with stabilization of the α-synuclein monomer by its C-terminus. Time-lapse imaging illustrated how cells form and accumulate Aggregates of α-synuclein. A substantial number of cells also reduced their Aggregate Load, primarily through formation of an aggresome, which could itself be cleared from the cell. The molecular chaperone Hsp70 not only prevented the formation of Aggregates, but also increased their reduction and clearance, underlining the therapeutic potential of similar strategies. In contrast to earlier assumptions build-up, reduction and clearance of α-synuclein aggregation thus appear a highly dynamic process.
Ned Djilali - One of the best experts on this subject based on the ideXlab platform.
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a new thermostat for real time price demand response cost comfort and energy impacts of discrete time control without deadband
Applied Energy, 2015Co-Authors: Jakob Stoustrup, David P Chassin, P Agathoklis, Ned DjilaliAbstract:Thermostatically controlled electrical Loads can provide valuable energy storage and are prime candidates for fast acting demand response (DR) that can be used to mitigate highly variable renewable power generation and limited availability of ramping resources. When conventional thermostats are retrofitted for real-time price DR control, significant control errors can arise, particularly in the form of dispatch control drift. This paper identifies the underlying causes and presents a new residential thermostat design that enables accurate Aggregate Load control. The new design gives rise to linear time-invariant models of Aggregate Load control and demand response, which facilitate the design of highly accurate Load-based regulation services for electricity interconnections. Detailed simulation and performance studies coupling a residential house and feeder models are presented to show how consumer comfort and cost savings are achieved and how energy use is impacted for cities in three different climatic zones. During peak times, the new thermostat imparts the entire residential Load an energy demand elasticity of about 10–25%. Larger demand elasticities could be achieved by extending the control strategy to other residential thermostatic Loads. The proposed thermostat design can operate in the real-time distribution capacity auction system and can provide all the benefits associated with transactive systems, and in particular facilitate increased integration of renewable resources.
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Wind integration in self-regulating electric Load distributions
Energy Systems, 2012Co-Authors: Simon Parkinson, Curran Crawford, Dan Wang, Ned DjilaliAbstract:The purpose of this paper is to introduce and assess an alternative method of mitigating short-term wind energy production variability through the control of electric Loads. In particular, co-located populations of electric vehicles and heat pumps are targeted to provide regulation-based ancillary services, as the inherent operational flexibility and autonomous device-level control strategy associated with these Load-types provide an ideal platform to mitigate enhanced variability within the power system. An optimal control strategy capable of simultaneously balancing these grid-side objectives with those typically expected on the demand-side is introduced. End-use digital communication hardware is used to track and control population dynamics through the development of online Aggregate Load models equivalent to conventional dispatchable generation. The viability of the proposed Load control strategy is assessed through model-based simulations that explicitly track end-use functionality of responsive devices within a power systems analysis typically implemented to observe the effects of integrated wind energy systems. Results indicate that there is great potential for the proposed method to displace the need for increased online regulation reserve capacity in systems considering a high penetration of wind energy, thereby allowing conventional generation to operate more efficiently.
Jovica V Milanovic - One of the best experts on this subject based on the ideXlab platform.
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framework for estimation of daily variation of dynamic response of Aggregate Load
IEEE PES Innovative Smart Grid Technologies Conference, 2013Co-Authors: Jovica V MilanovicAbstract:In order to illustrate daily variation of dynamic characteristics of the Load for different types of Load, time-varying Aggregate Load responses are derived in this paper. Hourly participation of different Load categories and dynamic responses of individual Load categories are necessary information for the derivation of time-varying Aggregate Load responses. The Load participations of individual Load types in Aggregate Load are derived from surveys or directly measured daily Load curves of different Load types. Dynamic responses of individual Load categories are captured from the simulation or field measurements and emulated with suitable mathematical formula. The Aggregate dynamic responses are derived by scaling the individual Load dynamic responses with respective Load contributions and summing up, resulting in hourly real and reactive power demand dynamic response curves. All hourly curves are finally presented in daily demand response surfaces which simultaneously provide the information of dynamic responses and hourly demand.
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ISGT Europe - Framework for estimation of daily variation of dynamic response of Aggregate Load
IEEE PES ISGT Europe 2013, 2013Co-Authors: Jovica V MilanovicAbstract:In order to illustrate daily variation of dynamic characteristics of the Load for different types of Load, time-varying Aggregate Load responses are derived in this paper. Hourly participation of different Load categories and dynamic responses of individual Load categories are necessary information for the derivation of time-varying Aggregate Load responses. The Load participations of individual Load types in Aggregate Load are derived from surveys or directly measured daily Load curves of different Load types. Dynamic responses of individual Load categories are captured from the simulation or field measurements and emulated with suitable mathematical formula. The Aggregate dynamic responses are derived by scaling the individual Load dynamic responses with respective Load contributions and summing up, resulting in hourly real and reactive power demand dynamic response curves. All hourly curves are finally presented in daily demand response surfaces which simultaneously provide the information of dynamic responses and hourly demand.
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establishing harmonic distortion level of distribution network based on stochastic Aggregate harmonic Load models
IEEE Transactions on Power Delivery, 2007Co-Authors: Jovica V MilanovicAbstract:This paper presents a stochastic Aggregate harmonic Load (AHL) model built from physical Load parameters. Parameters used include nonlinear Load composition, diversity factors, and nonlinear Load participation in total demand. They are obtained from samples of customer Load database of different sectors of customers. The Aggregate Load modules are developed for harmonic simulation of distribution network using commercially available software. Uncertainties in Loading conditions, Load composition and Aggregate harmonic Load parameters are taken into account separately and simultaneously to determine voltage harmonic distortion levels in distribution network. The simulations performed on a large, realistic distribution network using developed AHL modules give realistic voltage distortion levels/ranges. The results of simulations are in agreement with field measurement results
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Stochastic Assessment of Harmonic Distortion Level of Medium Voltage Radial Distribution Network
2006 International Conference on Probabilistic Methods Applied to Power Systems, 2006Co-Authors: Jovica V MilanovicAbstract:This paper presents a stochastic assessment of total harmonic voltage distortion (THDv) level of radial medium voltage distribution network using Monte Carlo simulation based on probabilistic harmonic current spectra of typical Aggregate Load types obtained from harmonic field measurements as inputs. High and low power demand periods of Aggregate Loads at each network bus are incorporated into the Monte Carlo simulation to account for the influence of power demand on harmonic voltage distortion, which then associate the respective THDv probability distribution curves to specific times of day. Simulation of a case example shows promising and realistic results.
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establishment of Load composition in Aggregate harmonic Load model at lv buses based on field measurements
Electricity Distribution 2005. CIRED 2005. 18th International Conference and Exhibition on, 2005Co-Authors: Jovica V MilanovicAbstract:This paper presents the methodology developed to derive the linear and nonlinear Load composition of an Aggregate harmonic Load model based on harmonic measurements taken at the service entrance feeder. Based on harmonic current spectra of typical nonlinear Loads and Aggregate harmonic Loads obtained through measurement at service entrance, a weighted coefficient representative of the percentage combination of each type of nonlinear Load is determined by solving a set of simultaneous equations with complex variables. Subsequently, linear Load fraction is determined through SUPERHARM simulation of the modeled Aggregate Load.
Robert Schober - One of the best experts on this subject based on the ideXlab platform.
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Real-Time Pricing for Demand Response Based on Stochastic Approximation
IEEE Transactions on Smart Grid, 2014Co-Authors: Pedram Samadi, Vincent Wai Sum Wong, Hamed Mohsenian-rad, Robert SchoberAbstract:In this paper, we propose a new pricing algorithm to minimize the peak-to-average ratio (PAR) in Aggregate Load demand. The key challenge that we seek to address is the energy provider's uncertainty about the impact of prices on users' Load profiles, in particular when users are equipped with automated energy consumption scheduling (ECS) devices. We use an iterative stochastic approximation approach to design two real-time pricing algorithms based on finite-difference and simultaneous perturbation methods, respectively. We also propose the use of a system simulator unit (SSU) that employs approximate dynamic programming to simulate the operation of the ECS devices and users' price-responsiveness. Simulation results show that our proposed real-time pricing algorithms reduce the PAR in Aggregate Load and help the users to reduce their energy expenses.
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tackling the Load uncertainty challenges for energy consumption scheduling in smart grid
IEEE Transactions on Smart Grid, 2013Co-Authors: Pedram Samadi, Hamed Mohsenianrad, Vincent Wai Sum Wong, Robert SchoberAbstract:In this paper, we propose a novel optimization-based real-time residential Load management algorithm that takes into account Load uncertainty in order to minimize the energy payment for each user. Unlike most existing demand side management algorithms that assume perfect knowledge of users' energy needs, our design only requires knowing some statistical estimates of the future Load demand. Moreover, we consider real-time pricing combined with inclining block rate tariffs. In our problem formulation, we take into account different types of constraints on the operation of different appliances such as must-run appliances, controllable appliances that are interruptible, and controllable appliances that are not interruptible. Our design is multi-stage. As the demand information of the appliances is gradually revealed over time, the operation schedule of controllable appliances is updated accordingly. Simulation results confirm that the proposed energy consumption scheduling algorithm can benefit both users, by reducing their energy expenses, and utility companies, by improving the peak-to-average ratio of the Aggregate Load demand.
