Working memory revived in older adults by synchronizing rhythmic brain circuits

Published in final edited form as: Nat Neurosci. 2019 May ; 22(5): 820–827. doi:10.1038/s41593-019-0371-x.Understanding normal brain aging and developing methods to maintain or improve cognition in older adults are major goals of fundamental and translational neuroscience. Here we show a core feature of cognitive decline—working-memory deficits—emerges from disconnected local and long-range circuits instantiated by theta–gamma phase–amplitude coupling in temporal cortex and theta phase synchronization across frontotemporal cortex. We developed a noninvasive stimulation procedure for modulating long-range theta interactions in adults aged 60–76 years. After 25 min of stimulation, frequency-tuned to individual brain network dynamics, we observed a preferential increase in neural synchronization patterns and the return of sender–receiver relationships of information flow within and between frontotemporal regions. The end result was rapid improvement in working-memory performance that outlasted a 50 min post-stimulation period. The results provide insight into the physiological foundations of age-related cognitive impairment and contribute to groundwork for future non-pharmacological interventions targeting aspects of cognitive decline.Accepted manuscrip

Automatic Parking Application

The purpose of this utility application is to automatically remind the users where their vehicle is parked. Using many sensors and features of the Apple iPhone, we can track changes in users’ behaviors and their surrounding such as air pressure, physical movement, connection proximity, and coordinate position. These allow for detecting not just the parking position, but also altitude and interior approximation within parking structures. Using a periodic assessment loop, this application silently waits for changes, remaining out of sight of common user activity. During an assessment, nearby connections, user position, and activity readings are evaluated. If a significant event, such as getting in a car or driving into a known parking location occurs, relevant methods are initiated, allowing for greater accuracy and ultimately a better user experience. Anyone who drives knows the struggle of searching for a parking spot for their vehicle. Finding the location of your parked car could even be more stressful. You may end up with walking up and down the stairs of a parking garage, wandering through a shopping center lot, or walking several blocks in the street only to remember the location of your car. Even once the car is located, it may be covered in tickets or impounded because of parking regulations. This scenario is especially true when users find themselves in a new city or in an unfamiliar part of the town. This application offers solutions to all of the cases mentioned above. An overview map displays nearby locations. Parking meters can be started to estimate fees and trigger alerts when time is low. When hunting for the tracked vehicle, directions can be requested through the application. Currently this application demonstrates the algorithms necessary to track a user’s vehicle through Bluetooth or Wi-Fi connection proximity. Utilizing Apple’s monitored regions, locations of interest allow for significant awareness by waking the application and performing relevant readings. Indoor position is determined using altitude readings, position plots, and headings with known location schematics. Users can save their personal locations and access features such as the building rendering, parking meter, and guided directions. A possible industry implementation of this application is the monitoring of businesses’ lots, allowing parking demand prediction along with restricting availability.https://scholarscompass.vcu.edu/capstone/1174/thumbnail.jp

Brain-state determines learning improvements after transcranial alternating-current stimulation to frontal cortex

Published in final edited form as: Brain Stimul. 2018 ; 11(4): 723–726. doi:10.1016/j.brs.2018.02.008BACKGROUND Theories of executive control propose that communication between medial frontal cortex (MFC) and lateral prefrontal cortex (lPFC) is critical for learning. 6-Hz phase synchronization may be the mechanism by which neural activity between MFC and lPFC is coordinated into a functional network. Recent evidence suggests that switching from eyes closed to open may induce a change in brain-state reflected by enhanced executive control and related functional connectivity. OBJECTIVE/HYPOTHESIs To examine whether causal manipulation of MFC and lPFC can improve learning according to the brain-state induced by switching from eyes closed to open. METHODS Within-subjects, sham-controlled, double-blind study of 30 healthy subjects, each receiving 6-Hz in-phase high definition transcranial alternating-current stimulation (HD-tACS) applied to MFC and right lPFC prior to performing a time estimation task. RESULTS HD-tACS with eyes open improved learning ability relative to sham, whereas HD-tACS with eyes closed had no significant effect on behavior. CONCLUSION Results suggest a phase-sensitive mechanism in frontal cortex mediates components of learning performance in a state-dependent manner.Accepted manuscrip

Golden Parachutes, Incentives, and the Cost of Debt

We examine the relation between the presence of golden parachutes and the cost of debt financing. We hypothesize that since golden parachutes compensate CEOs in the event of termination, CEOs with golden parachutes will have an incentive to increase firm risk and decrease effort, and this will lead to a higher cost of debt. Consistent with these hypotheses, we document a significant positive relation between the use of golden parachutes and the cost of debt. We confirm these results with a natural experiment using a difference-in-difference specification based on a 2004 change in IRS tax regulations. Moreover, we find that the adoption of a golden parachute is associated with an increase in firm risk, a higher likelihood of CEO turnover, and a lower operating performance. Overall, the evidence suggests that golden parachutes are primarily negative for the firm and for debt holders in particular.Golden parachutes, cost of debt, takeover probability, firm risk, CEO turnover

EAGLE—A Scalable Query Processing Engine for Linked Sensor Data

Recently, many approaches have been proposed to manage sensor data using semantic web technologies for effective heterogeneous data integration. However, our empirical observations revealed that these solutions primarily focused on semantic relationships and unfortunately paid less attention to spatio–temporal correlations. Most semantic approaches do not have spatio–temporal support. Some of them have attempted to provide full spatio–temporal support, but have poor performance for complex spatio–temporal aggregate queries. In addition, while the volume of sensor data is rapidly growing, the challenge of querying and managing the massive volumes of data generated by sensing devices still remains unsolved. In this article, we introduce EAGLE, a spatio–temporal query engine for querying sensor data based on the linked data model. The ultimate goal of EAGLE is to provide an elastic and scalable system which allows fast searching and analysis with respect to the relationships of space, time and semantics in sensor data. We also extend SPARQL with a set of new query operators in order to support spatio–temporal computing in the linked sensor data context.EC/H2020/732679/EU/ACTivating InnoVative IoT smart living environments for AGEing well/ACTIVAGEEC/H2020/661180/EU/A Scalable and Elastic Platform for Near-Realtime Analytics for The Graph of Everything/SMARTE

Intellectual property and antitrust limitations on contract: comment

In their chapter in Dynamic Competition and Public Policy (2001, Cambridge University Press), Burtis and Kobayashi never defined their model's discount rate, making replicating their simulation results difficult. Through our own simulations, we were able to verify their results when using a discount rate of 0.10. We also identified two new types of equilibria that the authors overlooked, doubling the number of distinct equilibria in the model.