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During everyday walking, we encounter challenges such as uneven terrain or curbs, all requiring adjustments to our gait patterns. These adjustments are made to circumvent the given obstacles and avoid falling or tripping. Exoskeletons have proven to assist walking by increasing walking speed and step length. However, most exoskeleton studies are traditionally carried out in a laboratory setting, which is an inaccurate depiction of everyday outdoor walking conditions. This study investigated the spatiotemporal gait parameters and hip kinematics during outdoor walking situations while wearing a passive-assistive hip exoskeleton (aLQ). Eleven healthy male participants walked on three 10-meter obstacle tracks at their self-selected walking speed with and without aLQ. The tracks were designed for the participants to (1) step up onto a sidewalk, (2) step over a pothole, and (3) walk without any obstacle (control situation). The cadence, gait velocity, step length, double stance time, and the 3D hip range of motion angles were extracted and compared for each track with and without aLQ. No significant changes were found for the spatiotemporal parameters with and without exoskeleton when navigating the obstacles. However, a significant decrease in the right hip internal rotation was observed when wearing the exoskeleton compared with without while stepping over (21%, p = 0.05) and while walking with no obstacle (6%, p = 0.04). These findings indicate that the gait of able-bodied adults was mostly unaffected during overground walking with a passive-assistive hip exoskeleton while navigating obstacles, proving that exoskeletons could be used safely in everyday situations.

BACKGROUND: The regulation of Factor X (FX) is critical to maintain the balance between blood coagulation and fluidity.OBJECTIVES: To functionally characterize the role of the FX autolysis loop in the regulation of the zymogen and active form of FX.METHODS: We introduced novel N-linked glycosylations on the surface-exposed loop spanning residues 143-150 (chymotrypsin numbering) of FX. The activity and inhibition of recombinant FX variants was quantified in pure component assays. The in vitro thrombin generation potential of the FX variants was evaluated in FX-depleted plasma.RESULTS: The Factor VIIa (FVIIa)-mediated activation and prothrombin activation was reduced, presumably through steric hinderance. Prothrombin activation was, however, recovered in presence of cofactor Factor Va (FVa) despite a reduced prothrombinase assembly. The introduced N-glycans exhibited position-specific effects on the interaction with two FXa inhibitors: tissue factor pathway inhibitor (TFPI) and antithrombin (ATIII). Ki for the inhibition by full-length TFPI of these FXa variants was increased by 7- to 1150-fold, while ATIII inhibition in the presence of the heparin-analogue Fondaparinux was modestly increased by 2- to 15-fold compared to wild type. When supplemented in zymogen form, the FX variants exhibited reduced thrombin generation activity relative to wild-type FX, whereas enhanced procoagulant activity was measured for activated FXa variants.CONCLUSION: The autolysis loop participate in all aspects of FX regulation. In plasma-based assays, a modest decrease in FX-activation rate appeared to knock down the procoagulant response even when down regulation of FXa activity by inhibitors was reduced.

The regulation of Factor X (FX) is critical to maintain hemostasis. To gain insights to the regulation of the active and zymogen form of coagulation FX, we probed specific molecular interactions by introducing novel N-linked glycosylations on the surface-exposed loop spanning residues 143-150 (chymotrypsin numbering) of FX. Introduction of N-glycans in the autolysis loop of these FX variants decreased Factor VIIa (FVIIa)-mediated activation ~3-fold and prothrombin activation 2- to 10-fold presumably through steric hinderance. Prothrombin activation was, however, recovered in presence of cofactor Factor Va (FVa) despite a reduced prothrombinase assembly. The introduced N-glycans exhibited position-specific effects on the interaction with two FXa inhibitors: tissue factor pathway inhibitor (TFPI) and antithrombin (ATIII). Ki for the inhibition by full-length TFPI of these FXa variants was increased by 7- to 1150-fold, while ATIII inhibition in the presence of the heparin-analogue Fondaparinux was modestly increased by 2- to 15-fold compared to wild type. To probe the in vitro hemostatic effect of the FX variants, the thrombin generation potential in FX-depleted plasma was evaluated. When supplemented in zymogen form, the FX variants exhibited reduced thrombin generation activity relative to wild-type FX, whereas enhanced procoagulant activity was measured for activated FX variants with N-glycosylation at positions 148-150. These results indicate that residues of the surface-exposed autolysis loop and residues close by participate in FX activation, proteolytic activity and inhibition of FXa by TFPI and ATIII. In plasma-based assays, a modest decrease in FX-activation rate appeared to compensate for the collective reduction in inhibitor interactions.

This is a case of a two-year-old boy with a ganglion arising from the sternoclavicular joint. Ganglia are rare in the pediatric population, with less than 2% occurring under the age of 2 years old. Additionally, sternoclavicular joint ganglia are also exceedingly rare. The case illustrates the importance of keeping ganglion within the differential diagnosis for palpable subcutaneous masses, even in young children, especially when they are seen to connect to the joint.

Microgrids have repeatedly demonstrated the ability to provide uninterrupted service to critical end-use loads during normal outages, severe weather events, and natural disasters. While their ability to provide critical services is well documented, microgrids present a more dynamic operational environment than grid-connected distribution systems. The electrodynamics of a microgrid are commonly driven by the high inertia of rotating generators, which are common in many microgrids. In such high-inertia systems, the impact of end-use load electromechanical dynamics are often not examined. However, with the increased penetration of inverter-based generation with little or no inertia, it is necessary to consider the impact that the dynamics of the end-use loads have on the operations of microgrids, particularly for a resiliency-based operation. These operations include, but are not limited to, switching operations, loss of generating units, and the starting of induction motors. This paper examines the importance of including multi-state electromechanical dynamic models of the end-use load when evaluating the operations of low inertia microgrids, and shows that by properly representing their behavior, it is possible to cost effectively size equipment while supporting resilient operations of critical end-use loads.

The deployment of new sensors and devices on electric distribution systems is increasing the awareness of phenomena characterized by intermittent periods of highly dynamic activity that occur within extended periods of relatively static behavior. The deployment of new devices has enabled the observation of these phenomena; however, the currently available simulation methods cannot accurately reproduce the entire system behavior. Existing simulation methods, and their associated models, are able to capture portions of these phenomena, but there is not a method for efficiently modeling the entire event in a single simulation. This paper presents a novel method of adaptive simulation that enables automated transitions between quasi-static time-series and electromechancial simulation modes, as necessary to capture relevant system dynamics. The transitions between the simulation modes are triggered automatically during the running simulation based on the evolution of the system variables, utilizing multistate modes for generators and motors. This method allows for a single simulation that spans the entire time-frame, has the ability to capture dynamic events, and includes all relevant power system controls. The method of adaptive simulation can support the direct analysis of dynamic power system events, co-simulation of transmission and distribution systems, the development of control systems, and the development of reduced-order models.

Electric distribution systems around the world are seeing an increasing number of utility-owned and non-utility-owned (customer-owned) intelligent devices and systems being deployed. New deployments of utility-owned assets include self-healing systems, microgrids, and distribution automation. Non-utility-owned assets include solar photovoltaic generation, behind-the-meter energy storage systems, and electric vehicles. While these deployments provide potential data and control points, the existing centralized control architectures do not have the flexibility or the scalability to integrate the increasing number or variety of devices. The communication bandwidth, latency, and the scalability of a centralized control architecture limit the ability of these new devices and systems from being engaged as active resources. This paper presents a standards-based architecture for the distributed power system controls, which increases operational flexibility by coordinating centralized and distributed control systems. The system actively engages utility and non-utility assets using a distributed architecture to increase reliability during normal operations and resiliency during extreme events. Results from laboratory testing and preliminary field implementations, as well as the details of an ongoing full-scale implementation at Duke Energy, are presented.

During the past century, many brackish shallow lakes worldwide have become eutrophic. How the zooplankton have responded to this development is not well elucidated. Here, we analysed the decadal changes (from 1999–2000 to 2017–2018) in zooplankton biomass, body mass, and potential top-down control on phytoplankton during summer in 4 Danish shallow brackish lakes (Lund Fjord, Han Vejle, Selbjerg, and Glombak) subjected to varying degrees of eutrophication. Significant reductions of zooplankton biomass, body mass, the ratio of large-sized cladoceran to total cladoceran biomass, and the ratio of zooplankton to phytoplankton biomass were observed in low to moderately vegetated lakes (Selbjerg and Glombak). However, in the macrophyte-dominated lake (Han Vejle), zooplankton biomass, body mass, and the contribution of large-sized cladocerans (Daphnia spp.) to total cladoceran biomass increased without a corresponding increase in the zooplankton to phytoplankton biomass ratio, which may be attributed to the refuge effect of submerged macrophytes. Using the pooled dataset, multivariate analysis indicated that total phosphorus concentrations and fish abundance were the main drivers of shifts in the zooplankton community and that zooplankton body mass was strongly negatively related to fish abundance. From a lake management perspective, our results suggest that eutrophication, through increased fish predation and reduced submerged vegetation abundance, has major effects on zooplankton communities in temperate coastal brackish shallow lakes, and a reduction in the zooplankton grazing pressure on phytoplankton is predicted if the eutrophication process continues.

With the rapid growth of internet-connected smart devices capable of exchanging energy price information and adaptively controlling energy consumption of connected loads, the role of transactive control is expected to become more prominent in the modern grid. Transactive control systems integrate the wholesale and retail energy markets, and enable active participation of end users employing distributed assets in the smart grid. The use of internet for the communication of data between the controllers at the building and the electric grid, makes the system susceptible to cyber-attacks. A skilled adversary can potentially manipulate the exchanged data with the intention of inflicting damage to the system. In this paper, four categories of metrics are put forth for evaluating the performance of the system when under data integrity attacks. A model for scaling-based data integrity attack has been described, and co-simulations have been performed on a 240 bus WECC transmission system model with detailed modeling of distribution systems at specific buses. Our results show that scaling attacks can have non-trivial impacts on the operational, financial, and comfort aspects of the transactive control system, and the impacts depend on the type of scaling attack, and its time and magnitude.

Demand response represents a significant but largely untapped resource that can greatly enhance the flexibility and reliability of power systems. This paper proposes a hierarchical control framework to facilitate the integrated coordination between distributed energy resources and demand response. The proposed framework consists of coordination and device layers. In the coordination layer, prior to each scheduling period, each coordinator receives the aggregated utility or cost functions as well as the power operating ranges from aggregators or device controllers. Then, various resources or their aggregations are optimally coordinated in a distributed manner to achieve the system-level objectives. The obtained regulation signals are sent back to aggregators or device controllers for real-time control. In the device layer, at the scheduling stage, the controller at each device reports to coordinators (directly or through aggregators) the required information for optimal coordination, and receives the regulation signals from its commander once the coordination is completed. During the real-time operation, individual resources are controlled to follow the optimal power dispatch signals. For practical applications, a method is presented to determine the utility functions of controllable loads by accounting for the real-time load dynamics and the preferences of individual customers. The effectiveness of the proposed framework is validated by detailed simulation studies.

Transactive control strategies for managing realtime energy consumption have been under study for a number of years. This work investigates a hierarchical control framework for such a system. This framework consist of two control layers to aggregate and reflect the flexibility of demand assets in the wholesale markets. Computation at each layer and communication across layers is designed to be minimal. The minimization of data exchange is done through demand curve approximation. To manage these two approximations, two intermediate layer dispatch strategies are compared: price-priority and quantity- priority. The price-priority dispatch results in significant differences between the wholesale cleared load and the actual retail load while the quantity-priority dispatch manages load much better at the cost of introducing uncertainty into the business cases of the intermediate layers.

Restoration of end-use loads during bulk transmission system outages is a key challenge for electric utilities. During those outages, utilities often do not have enough resources to fully restore the end-use loads. System reconfiguration can provide access to non-utility assets that can enable restoration; however, not all available switching options are feasible due to voltage and load limits. Engaging non-utility assets for system restoration during system events requires commensurate compensation and incentive calculation. This paper presents a new transactive energy system framework (TESF) to incentivize distributed energy resources (DERs) to provide reactive power for supporting the self-healing functions of distribution management system (DMS). TESF engages non-utility DERs during resiliency events by incentivizing them through transactive signals computed using marginal cost of producing reactive power and marginal benefit of additional switching operations. TESF calculates additional switching options, which DMS then leverages to identify new optimal switching plans to restore additional loads. A test system consisting of multiple IEEE-13 node distribution feeders is used to demonstrate the performance of the proposed method. For the given system configuration and use-case, TESF results in 24.82% additional load restoration and one additional switching operation.

Electrical power system stability under high penetration of intermittent renewable energy generation, such as wind and solar energy, has become a high concern. It is unpredictable and hard to control due to little inertial behavior characteristic to these generation resources. To help mitigate possibly undesirable frequency excursions, demand-side frequency control presents an emerging solution. By observing the frequency deviation, devices could switch operating modes for a short time to rebalance generation. To analyze device level control algorithms, aggregate models for their behavior are needed. Refrigerators are household devices that could help with load modulation. This paper uses real measured data to analyze the refrigerator behavior, learn about its operating mode and power consumption ranges. A Markov chain process is proposed to model the transition of a refrigerator population from one operating mode to another, such that the overall load is modulated according to the control input. The Markov-chain model can be used to design control so that the overall load is modulated according to the control input.

Aggregation can be a major challenge in the development of antibody-based pharmaceuticals as it can compromise the quality of the product during bioprocessing, formulation, and drug administration. To avoid aggregation, developability assessment is often run in parallel with functional optimization in the early screening phases to flag and deselect problematic molecules. As developability assessment can be demanding with regard to time and resources, there is a high focus on the development of molecule design strategies for engineering molecules with a high developability potential. Previously, Dudgeon et al. [(2012) Proc. Natl. Acad. Sci. U. S. A. 109, 10879-10884] demonstrated how Asp substitutions at specific positions in human variable domains and single-chain variable fragments could decrease the aggregation propensity. Here, we have investigated whether these Asp substitutions would improve the developability potential of a murine antigen binding fragment (Fab). A full combinatorial library consisting of 393 Fab variants with single, double, and triple Asp substitutions was first screened in silico with Rosetta; thereafter, 26 variants with the highest predicted thermodynamic stability were selected for production. All variants were subjected to a set of developability studies. Interestingly, most variants had thermodynamic stability on par with or improved relative to that of the wild type. Twenty-five of the variants exhibited improved nonspecificity. Half of the variants exhibited improved aggregation resistance. Strikingly, while we observed remarkable improvement in the developability potential, the Asp substitutions had no substantial effect on the antigenic binding affinity. Altogether, by combining the insertion of negative charges and the in silico screen based on computational models, we were able to improve the developability of the Fab rapidly.

The study was partly funded by the Schleswig-Holstein’s Government-Owned Company for Coastal Protection, National Parks and Ocean Protection, Wadden Sea National Park Administration of Lower Saxony (Richard Czeck) and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (FKZ: 03 275 20 and FKZ: 0329946B). This publication was supported by Deutsche Forschungsgemeinschaft and University of Veterinary Medicine Hannover, Foundation within the funding programme Open Access Publishing. Odontocetes have evolved a rich diversity of prey- and habitat-specific foraging strategies, which allows them to feed opportunistically on locally and temporally abundant prey. While habitat-specific foraging strategies have been documented for some odontocete species, this is less known for the harbour porpoise (Phocoena phocoena). We collected multiple years of acoustic data using echolocation click loggers to analyse porpoise occurrence and buzzing behaviour, indicating feeding, in the German Wadden Sea (North Sea). Seasonal, diel and tidal effects were studied using Generalised Estimating Equations (GEE-GAMs). Locally season, time of day and tidal time significantly influenced the probability of porpoise detections and detection of foraging sequences (buzzes). Hunting strategies, and therefore frequency of buzzes, were likely affected by prey distribution and large differences between POD locations indicated that porpoises used highly specific behaviour adapted to tide and time of day to efficiently feed on the available prey. Strong seasonal and spatial variation in diel and tidal effects underline the importance of long-term observations. Studies on porpoise behaviour are often based on short-term observations and might rather reflect a seasonal than a general pattern. The results of this study show clearly that significant changes in porpoise behaviour can be found in short and long-term observations. Here some features are based on short term determinants and others are stable over years and care should be taken about drawing general conclusions based on local patterns. Highly variable spatio-temporal patterns indicate a high flexibility of porpoises in a highly variable environment and address a challenge for complex conservation management plans. Publisher PDF

Transactive energy is a control technique that uses market mechanisms to achieve desired control objectives. A number of studies have identified a well-known economic theory effect called a “cobweb” that can occur when the transactive control system is not properly designed. This work proposes a control framework to mitigate this effect by adding an extra control layer. This proposed control layer expresses the flexibility of load on the distribution side into the transmission system. By using FNCS, a co-simulation platform, new control framework is evaluated on a power system model composed of a single transmission system with the potential of thousands of flexible distribution systems. The co-simulation is able to replicate the cobweb effect and demonstrate that improper transactive control design can create oscillations at high penetrations of price-responsive loads. Furthermore, the proposed transactive control system is shown to be able to eliminate the cobweb effect while also effectively diminishing price and load spikes.

Turoctocog alfa (NovoEight) is a third-generation recombinant factor VIII (rFVIII) with a truncated B-domain that is manufactured in Chinese hamster ovary cells. No human or animal-derived materials are used in the process. The aim of this study is to describe the molecular design and purification process for turoctocog alfa. A five-step purification process is applied to turoctocog alfa: protein capture on mixed-mode resin; immunoaffinity chromatography using a unique, recombinantly produced anti-FVIII mAb; anion exchange chromatography; nanofiltration and size exclusion chromatography. This process enabled reduction of impurities such as host cell proteins (HCPs) and high molecular weight proteins (HMWPs) to a very low level. The immunoaffinity step is very important for the removal of FVIII-related degradation products. Manufacturing scale data shown in this article confirmed the robustness of the purification process and a reliable and consistent reduction of the impurities. The contribution of each step to the final product purity is described and shown for three manufacturing batches. Turoctocog alfa, a third-generation B-domain truncated rFVIII product is manufactured in Chinese hamster ovary cells without the use of animal or human-derived proteins. The five-step purification process results in a homogenous, highly purified rFVIII product.

Transactive energy is a control technique that uses market mechanisms to achieve desired control objectives. Several simulation studies and field demonstrations were carried out in recent years, but all focused on small scale systems and purpose-built simplified models which are not always capable of pointing out all the advantages and shortcomings of transactive energy methods. This work describes a co-simulation framework built on a hierarchical control architecture that allows for conducting studies on the impacts of a very large-scale deployment of transactive energy. The hierarchical transactive control architecture adopted in this work helps with alleviating computation and communication burden to facilitate a more effective large scale real-time market operation among device level resources and the system level operators. The co-simulation framework is evaluated using off-the-shelf simulators on an integrated power system model of unprecedented scale composed of the Western Electricity Coordination Council transmission system with tens of thousands of distribution systems deployed with flexible device-level distributed energy resources.

Single-chain variable fragments (scFv) are widely used in several fields. However, they can be challenging to purify unless using expensive Protein L-based affinity adsorbents or affinity tags. In this work, a purification process for a scFv using mixed-mode (MM) chromatography was developed by design of experiments (DoE) and proteomics for host cell protein (HCP) quantification. Capture of scFv from human embryonic kidney 293 (HEK293) cell feedstocks was performed by hydrophobic charge induction chromatography (MEP HyperCel™), whereafter polishing was performed by anion hydrophobic MM chromatography (Capto Adhere™). The DoE designs of the polishing step included both binding and flow-through modes, the latter being the standard mode for HCP removal. Chromatography with Capto Adhere™ in binding-mode with elution by linear salt gradient at pH 7.5 resulted in optimal yield, purity and HCP reduction factor of 98.9 > 98.5%, and 14, respectively. Totally, 258 different HCPs were removed, corresponding to 84% of identified HCPs. The optimized conditions enabled binding of the scFv to Capto Adhere™ below its theoretical pI, while the majority of HCPs were in the flow-through. Surface property maps indicated the presence of hydrophobic patches in close proximity to negatively charged patches that could potentially play a role in this unique selectivity.

This paper presents a framework for testing distributed control algorithms that solve economic dispatch problems. Often times during development, distributed control algorithms are studied theoretically in detail and implemented on a single simulator as a numerical simulation. In order to realistically model a distributed control system, co-simulation of multiple simulators is required. The work presented here enables this through a framework developed using Framework for Network co-simulation (FNCS). This paper implements a consensus based distributed algorithm to solve economic dispatch in presence of communication network delays. Every agent participating in distributed economic dispatch is modeled as an individual simulator communicating only through a communication network simulator, making it a truly distributed framework. Tests are conducted to validate the algorithm against different types of communication network effects like delays and different data rates. This framework can be easily reused to test other types of distributed algorithms.

Existing approaches coordinating distributed energy resources (DERs) for grid services do not adequately evaluate the performance of such DER integration. Most studies are based on a single type of DER used for a single type of service, rather than the real-world requirements of coordinating a heterogeneous mix of DERs to provide multiple different grid services at different time-scales. Facilities also often face cybersecurity and interoperability challenges to experimenting and testing methodologies in this area. To overcome all of these challenges, Pacific Northwest National Laboratory, United Technologies Research Center, Southern California Edison, and Spirae coordinated to develop a federation between their organizations. This federation implements a cybersecure connection that facilitates near real-time communication between the four different physical sites. This not only enables control of DERs at different physical locations but also lets the software and hardware objects perform control experiments in a cybersecure environment at different time-scales. The hardware systems can consist of microgrids, building management systems, and emulated power systems objects. This paper provides a detailed overview of the federation setup and describes what this federation can be used for.

Inter-area oscillations have severely limited maximum power transfer among different areas in large-scale interconnected power grid. If not quickly damped as soon as possible, they may cause system breakup and even lead to large cascading blackouts. To increase the damping of inter-area oscillations, both power system stabilizer (PSS) and flexible AC transmission system (FACTS) controller have been widely considered, which affect the real power flow indirectly. However, the effectiveness of these controllers is restricted to the neighborhood of a prescribed set of operating conditions. In this paper, wide-area demand-side control is developed to directly modulate the real power of end-user loads for oscillation mitigation. The proposed control strategy is implemented in a hierarchical manner. At the device layer, individual end-user loads independently turn ON or OFF in response to the broadcasted signals from the coordinator during the real time. At the supervisory layer, autonomous responses of end-user loads are coordinated to ensure the desired power modulation. The effectiveness of the proposed wide-area demand-side control in improving small-signal stability is illustrated by simulations on a large-scale test system.

Springtails are important members of the soil fauna and play a key role in plant litter decomposition, for example through stimulation of the microbial activity. However, their interaction with soil microorganisms remains poorly understood and it is unclear which microorganisms are associated to the springtail (endo) microbiota. Therefore, we assessed the structure of the microbiota of the springtail Orchesella cincta (L.) using 16S rRNA gene amplicon sequencing. Individuals were sampled across sites in the field and the microbiota and in particular the endomicrobiota were investigated. The microbiota was dominated by the families of Rickettsiaceae, Enterobacteriaceae and Comamonadaceae and at the genus level the most abundant genera included Rickettsia, Chryseobacterium, Pseudomonas, and Stenotrophomonas. Microbial communities were distinct for the interior of the springtails for measures of community diversity and exhibited structure according to collection sites. Functional analysis of the springtail bacterial community suggests that abundant members of the microbiota may be associated with metabolism including decomposition processes. Together these results add to the understanding of the microbiota of springtails and interaction with soil microorganisms including their putative functional roles.

The effects of short-term high-intensity exercise on single fiber contractile function in humans are unknown. Therefore, the purposes of this study were: (a) to access the acute effects of repeated high-intensity exercise on human single muscle fiber contractile function; and (b) to examine whether contractile function was affected by alterations in the redox balance. Eleven elite cross-country skiers performed four maximal bouts of 1300 m treadmill skiing with 45 min recovery. Contractile function of chemically skinned single fibers from triceps brachii was examined before the first and following the fourth sprint with respect to Ca(2+) sensitivity and maximal Ca(2+) -activated force. To investigate the oxidative effects of exercise on single fiber contractile function, a subset of fibers was incubated with dithiothreitol (DTT) before analysis. Ca(2+) sensitivity was enhanced by exercise in both MHC I (17%, P

Volt/var control (VVC) of smart PV inverter is becoming one of the most popular solutions to address the voltage challenges associated with high PV penetration. This work focuses on the local droop VVC recommended by the grid integration standards IEEE1547, rule21 and addresses their major challenges i.e. appropriate parameters selection under changing conditions, and the control being vulnerable to instability (or voltage oscillations) and significant steady state error (SSE). This is achieved by proposing a two-layer local real-time adaptive VVC that has two major features i.e. a) it is able to ensure both low SSE and control stability simultaneously without compromising either, and b) it dynamically adapts its parameters to ensure good performance in a wide range of external disturbances such as sudden cloud cover, cloud intermittency, and substation voltage changes. A theoretical analysis and convergence proof of the proposed control is also discussed. The proposed control is implementation friendly as it fits well within the integration standard framework and depends only on the local bus information. The performance is compared with the existing droop VVC methods in several scenarios on a large unbalanced 3-phase feeder with detailed secondary side modeling., IEEE Transactions on Smart Grid, 2018

We are developing the Visual Steering and Modeling Environment (VSME) to enable the visual control and steering of smart grid simulations as well as the visualization of simulation behaviors, conditions, and results. Visual steering will allow planners and operators to visually adjust the parameters to a suite of coordinated and dynamic smart grid simulations and immediately see the effects in multi-perspective visualizations. A configurable dashboard connects and integrates parameters, simulations, data, and visualizations into a combined and coherent display.

With an ever-evolving power grid, concerns regarding how to maintain system stability, efficiency, and reliability remain constant because of increasing uncertainties and decreasing rotating inertia. To alleviate some of these concerns, demand response represents a viable solution and is virtually an untapped resource in the current power grid. This work describes a hierarchical control framework that allows coordination between distributed energy resources and demand response. This control framework is composed of two control layers: a coordination layer that ensures aggregations of resources are coordinated to achieve system objectives and a device layer that controls individual resources to assure the predetermined power profile is tracked in real time. Large-scale simulations are executed to study the hierarchical control, requiring advancements in simulation capabilities. Technical advancements necessary to investigate and answer control interaction questions, including the Framework for Network Co-Simulation platform and Arion modeling capability, are detailed. Insights into the interdependencies of controls across a complex system and how they must be tuned, as well as validation of the effectiveness of the proposed control framework, are yielded using a large-scale integrated transmission system model coupled with multiple distribution systems.

Even though the deleterious effects of increased reactive oxygen species (ROS) levels have been implicated in a variety of neurodegenerative disorders, the triggering events that lead to the increased ROS and successive damages are still ill defined. Mitochondria are the key organelles controlling the ROS balance, being their main source and also counteracting them by the action of the ROS scavenging system. Mitochondria, moreover, control the presence of ROS-damaged proteins by action of the protein quality control system. One of its components is the mitochondrial chaperone Hsp60 assisting the folding of a subset of mitochondrial matrix proteins. Mutations in Hsp60 cause a late onset form of the neurodegenerative disease hereditary spastic paraplegia (SPG13). In this study, we aimed to address the molecular consequences of Hsp60 shortage. We here demonstrate that a heterozygous knockout Hsp60 model that recapitulates features of the human disease, exhibits increased oxidative stress in neuronal tissues. Moreover, we indicate that the increase of ROS is, at least in part, due to impaired folding of the superoxide dismutase MnSOD, a key antioxidant enzyme. We observed that the Hsp60 and MnSOD proteins interact. Based on these results, we propose that MnSOD is a substrate of the Hsp60 folding machinery and that under conditions of diminished availability of Hsp60, MnSOD is impaired in reaching the native state. This suggests a possible link between Hsp60-dependent protein quality control and the ROS scavenging systems that may have the function to increase ROS production under conditions of folding stress.