Transcranial Electrical Stimulation targeting limbic cortex increases the duration of human deep sleep

Background: Researchers have proposed that impaired sleep may be a causal link in the progression from Mild Cognitive Impairment (MCI) to Alzheimer's Disease (AD). Several recent findings suggest that enhancing deep sleep (N3) may improve neurological health in persons with MCI, and buffer the risk for AD. Specifically, Transcranial Electrical Stimulation (TES) of frontal brain areas, the inferred source of the Slow Oscillations (SOs) of N3 sleep, can extend N3 sleep duration and improve declarative memory for recently learned information. Recent work in our laboratory using dense array Electroencephalography (dEEG) localized the sources of SOs to anterior limbic sites – suggesting that targeting these sites with TES may be more effective for enhancing N3. Methods: For the present study, we recruited 13 healthy adults (M = 42 years) to participate in three all-night sleep EEG recordings where they received low level (0.5 mA) TES designed to target anterior limbic areas and a sham stimulation (placebo). We used a convolutional neural network, trained and tested on professionally scored EEG sleep staging, to predict sleep stages for each recording. Results: When compared to the sham session, limbic-targeted TES significantly increased the duration of N3 sleep. TES also significantly increased spectral power in the 0.5–1 Hz frequency band (relative to pre-TES epochs) in left temporoparietal and left occipital scalp regions compared to sham. Conclusion: These results suggest that even low-level TES, when specifically targeting anterior limbic sites, can increase deep (N3) sleep and thereby contribute to healthy sleep quality.Fil: Hathaway, Evan. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Morgan, Kyle. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Carson, Megan. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Shusterman, Roma. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Fernandez Corazza, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; ArgentinaFil: Luu, Phan. University of Oregon; Estados UnidosFil: Tucker, Don M.. University of Oregon; Estados Unido

Focal limbic sources create the large slow oscillations of the EEG in human deep sleep

Background: Initial observations with the human electroencephalogram (EEG) have interpreted slow oscillations (SOs) of the EEG during deep sleep (N3) as reflecting widespread surface-negative traveling waves that originate in frontal regions and propagate across the neocortex. However, mapping SOs with a high-density array shows the simultaneous appearance of posterior positive voltage fields in the EEG at the time of the frontal-negative fields, with the typical inversion point (apparent source) around the temporal lobe. Methods: Overnight 256-channel EEG recordings were gathered from 10 healthy young adults. Individual head conductivity models were created using each participant's own structural MRI. Source localization of SOs during N3 was then performed. Results: Electrical source localization models confirmed that these large waves were created by focal discharges within the ventral limbic cortex, including medial temporal and caudal orbitofrontal cortex. Conclusions: Although the functional neurophysiology of deep sleep involves interactions between limbic and neocortical networks, the large EEG deflections of deep sleep are not created by distributed traveling waves in lateral neocortex but instead by relatively focal limbic discharges.Fil: Morgan, Kyle K.. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Hathaway, Evan. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Carson, Megan. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Fernandez Corazza, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; ArgentinaFil: Shusterman, Roma. Brain Electrophysiology Laboratory Company; Estados UnidosFil: Luu, Phan. Brain Electrophysiology Laboratory Company; Estados Unidos. University of Oregon; Estados UnidosFil: Tucker, Don M.. University of Oregon; Estados Unidos. Brain Electrophysiology Laboratory Company; Estados Unido

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

Design and construction of a probe positioning system for pulsed plasma thruster diagnostics

In order to make advancements in the area of propulsion, it is necessary to study the capabilities of current technology. One type of spacecraft propulsion system currently under development is the pulsed plasma thruster (PPT). The goal of this project is to design and fabricate a computer controlled two-axis probe positioning system which can be used to investigate the plume of a PPT operating in a vacuum chamber. The effort was divided into three areas: (1) vacuum chamber refurbishment, (2) mechanical and electrical design of the probe positioning system (PPS), and (3) thermal modeling of the PPT support during thruster operation

Evaluating the impact of a minimally invasive pediatric surgeon on hospital practice: comparison of two children’s hospitals

© 2015, Springer Science+Business Media New York. Purpose: Widespread adoption of minimally invasive surgery (MIS) techniques in pediatric surgery has progressed slowly, and the shift in practice patterns has been variable among surgeons. We hypothesized that a pediatric surgeon committed to MIS could effectively change surgical practice by creating an emphasis on MIS. Methods: Annual case volumes from 2000 to 2009 at two tertiary care pediatric hospitals, one with a dedicated minimally invasive pediatric surgeon, were evaluated for trends in MIS for ten different operations. Univariate analyses of the differences between hospitals in the use of the open versus laparoscopic approach were performed. The Breslow–Day test was used to examine differences in use of laparoscopic procedures across hospitals in early versus middle and middle versus late time periods. Results: Between the two hospitals, for 9 of the 10 types of surgery, the number of laparoscopic and open procedures differed significantly (p values ranged from \u3c0.0001 to 0.003). Over the 10-year period, the hospital with a dedicated MIS surgeon had a larger proportion of procedures done laparoscopically for all years. This difference reached statistical significance for appendectomy (p \u3c 0.0001), congenital diaphragmatic hernia (p \u3c 0.0002), chest wall reconstruction (p \u3c 0.0001), cholecystectomy (p = \u3c0.0001), gastrostomy (p \u3c 0.0001), nissen fundoplication (p \u3c 0.0001) oophorectomy (p \u3c 0.0001), pyloromyotomy (p \u3c 0.0001) and splenectomy (p = 0.0006). After grouping the years into early (2000–2003), middle (2004–2006) and late (2007–2009) categories, the hospital with a dedicated MIS surgeon had a significantly higher rate of increase in use of laparoscopic surgery between the early and middle years for four procedures: diaphragmatic hernia repair (p = 0.003), chest wall reconstruction (p = 0.0086), cholecystectomy (0.0083) and endorectal pull-through (p = 0.025). Conclusion: The presence of a dedicated minimally invasive pediatric surgeon led to a significant change in surgical practice with an overall trend of increasing MIS several years in advance of a hospital that did not have a dedicated MIS surgeon. This has implications for resident training in academic medical centers and potential patient care outcomes

Evaluating the impact of a minimally invasive pediatric surgeon on hospital practice: comparison of two children\u27s hospitals.

© 2015, Springer Science+Business Media New York. Purpose: Widespread adoption of minimally invasive surgery (MIS) techniques in pediatric surgery has progressed slowly, and the shift in practice patterns has been variable among surgeons. We hypothesized that a pediatric surgeon committed to MIS could effectively change surgical practice by creating an emphasis on MIS. Methods: Annual case volumes from 2000 to 2009 at two tertiary care pediatric hospitals, one with a dedicated minimally invasive pediatric surgeon, were evaluated for trends in MIS for ten different operations. Univariate analyses of the differences between hospitals in the use of the open versus laparoscopic approach were performed. The Breslow–Day test was used to examine differences in use of laparoscopic procedures across hospitals in early versus middle and middle versus late time periods. Results: Between the two hospitals, for 9 of the 10 types of surgery, the number of laparoscopic and open procedures differed significantly (p values ranged from \u3c0.0001 to 0.003). Over the 10-year period, the hospital with a dedicated MIS surgeon had a larger proportion of procedures done laparoscopically for all years. This difference reached statistical significance for appendectomy (p \u3c 0.0001), congenital diaphragmatic hernia (p \u3c 0.0002), chest wall reconstruction (p \u3c 0.0001), cholecystectomy (p = \u3c0.0001), gastrostomy (p \u3c 0.0001), nissen fundoplication (p \u3c 0.0001) oophorectomy (p \u3c 0.0001), pyloromyotomy (p \u3c 0.0001) and splenectomy (p = 0.0006). After grouping the years into early (2000–2003), middle (2004–2006) and late (2007–2009) categories, the hospital with a dedicated MIS surgeon had a significantly higher rate of increase in use of laparoscopic surgery between the early and middle years for four procedures: diaphragmatic hernia repair (p = 0.003), chest wall reconstruction (p = 0.0086), cholecystectomy (0.0083) and endorectal pull-through (p = 0.025). Conclusion: The presence of a dedicated minimally invasive pediatric surgeon led to a significant change in surgical practice with an overall trend of increasing MIS several years in advance of a hospital that did not have a dedicated MIS surgeon. This has implications for resident training in academic medical centers and potential patient care outcomes