Examining sensory gating and processing speed in adults with autism using EEG

2018 Summer.Includes bibliographical references.Objectives. Most individuals with Autism Spectrum Disorder (ASD) experience sensory deficits in their auditory processing (Tomchek & Dunn, 2007). These deficits can further impact their ability to participate in their physical and social environments. One way to increase understanding of these deficits is through use of electroencephalography (EEG), which measures brain activity in real-time and is able to distinguish brain processes such as sensory processing and the deficits that might be occurring during this process (Davies & Gavin, 2007). This study's purpose is to understand how processing speed and ability to filter out irrelevant stimuli impacts adults with ASD compared to their neurotypical (NT) peers through measurements of latency of prominent brain activity following presentation of an auditory stimulus and sensory gating. This study also analyzed how active and passive attention states impact sensory gating and latency. Methods. 24 adults with autism (M = 23.3 years, SD = 3.8) and 24 neurotypical adults (M = 23.7 years, SD = 3.5) participated in this study. They completed a sensory gating paradigm in both an active and a passive listening condition. In the active condition they were asked to press a button when they heard a single click, and in the passive condition they simply stared at a static image on a screen while the auditory stimuli were presented to them. Results. The results showed that there are no significantly different sensory gating responses between the ASD and NT groups. Individuals with ASD had delayed processing speed as measured through latency as early as 100 milliseconds following an auditory stimulus. Both groups experienced slower processing in the passive condition starting at approximately 200 milliseconds post-stimulus onset. As expected, more gating was observed for both groups in the passive condition at early components, where-as the active condition - which required attention to the stimulus that is usually suppressed in this task - resulted in less gating. In the latest component analyzed, approximately 200 milliseconds post-stimulus, both groups showed more gating in the active attention state, which was the opposite of the expected results, and the possible reason for this unexpected result needs further exploration. Conclusions. These findings suggest that individuals with autism do not have deficits in the ability to filter out irrelevant stimuli, however, they are likely more impacted by delayed processing speeds. Implications for practice include allowing more time to process auditory information for individuals with autism, and using compensatory strategies to influence neural processing speeds and amount of gating in response to auditory stimuli through the use of activity demands to create either passive or active attention states

Association of habitual snoring with carotid intima-media thickness in young men

Purpose: The primary aims of this study are to: 1) compare carotid intima media thickness (CIMT) of young males who are habitual snorers compared to those who do not snore; 2) to compare CIMT between snorers and non-snorers to the intima media thickness (IMT) of the brachial artery, the control, that is not exposed to the vibrations from snoring; and 3) to determine the risk for developing obstructive sleep apnea (OSA) in snorers compared to non-snorers through the use of validated questionnaires. Methods: Subjects were classified as snorers (n=17) or non-snorers (n=6) according to the prescreening questionnaire. Height, weight, neck and waist circumferences, body composition, physical activity level, heart rate variability and accelerometer data were collected on each subject. Brachial and carotid IMT was imaged via ultrasonography; IMT measurements were compared between groups using brachial IMT as the control to compare CIMT between groups. Results: No significant group differences were noted for any study variable, however a correlation was found between CIMT and physical activity (PA) (expressed as MET-min/wk) (r=0.65, p = .001). After controlling for PA, mean CIMT was greater in snorers compared to non-snorers (0.367 mm vs. 0.310 mm respectively; p=.014). Brachial IMT did not differ between groups. Questionnaire data showed that 58.8% of snorers were at high risk for developing OSA compared to 0% for non-snorers. Conclusion: Results suggest that the vibrations from snoring may contribute to vascular remodeling in the carotid artery, and may be an early mechanism contributing to the development of endothelial dysfunction, and early subclinical sign of CVD risk in those at high risk for OSA

New model of calculating the energy transfer efficiency for the spherical theta-pinch device

Ion-beam-plasma-interaction plays an important role in the field of Warm Dense Matter (WDM) and Inertial Confinement Fusion (ICF). A spherical theta pinch is proposed to act as a plasma target in various applications including a plasma stripper cell. One key parameter for such applications is the free electron density. A linear dependency of this density to the amount of energy transferred into the plasma from an energy storage was found by C. Teske. Since the amount of stored energy is known, the energy transfer efficiency is a reliable parameter for the design of a spherical theta pinch device. The traditional two models of energy transfer efficiency are based on assumptions which comprise the risk of systematical errors. To obtain precise results, this paper proposes a new model without the necessity of any assumption to calculate the energy transfer efficiency for an inductively coupled plasma device. Further, a comparison of these three different models is given at a fixed operation voltage for the full range of working gas pressures. Due to the inappropriate assumptions included in the traditional models, one owns a tendency to overestimate the energy transfer efficiency whereas the other leads to an underestimation. Applying our new model to a wide spread set of operation voltages and gas pressures, an overall picture of the energy transfer efficiency results

"Gastroesophageal reflux disease"

Geoffrey C. Wall is an Associate Professor of Pharmacy Practice in the College of Pharmacy and Health Sciences. He can be contacted at [email protected]: Gastroesophageal reflux disease (GERD) is a pathologic condition of injury to the esophagus caused by regurgitation of gastric or gastroduodenal contents into the lumen of the esophagus. Histopathology of the esophageal mucosa may or may not be present. Gastroesophageal reflux of acid and gastric contents often causes a condition commonly referred to as heartburn. This is characterized as a retro-sternal burning sensation that radiates to the throat and interscapular region. It may be confused, even in the emergency room, with anginal pain or the onset of myocardial infarction; therefore its rapid diagnosis is important. In many patients GERD should be considered a chronic and lifelong illness and maintenance therapy is often needed. Repeated exposure of the esophagus to stomach contents leads to esophagitis. In severe cases, this can actually erode esophageal tissue (erosive esophagitis). In the last five to seven years several new treatment options for GERD have become available. These include antise-cretory agents such as the proton pump inhibitors, and new surgical techniques that have improved Nissen fundoplication safety and efficacy rates(3-4). Clinicians caring for patients with this common disorder need to understand the pathology behind GERD, its common (and uncommon) clinical manifestations, and current treatment options as recommended by the American College of Gastroenterology

The Influence on Climate Change of Differing Scenarios for Future Development Analyzed Using the MIT Integrated Global System Model

Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/).A wide variety of scenarios for future development have played significant roles in climate policy discussions. This paper presents projections of greenhouse gas (GHG) concentrations, sea level rise due to thermal expansion and glacial melt, oceanic acidity, and global mean temperature increases computed with the MIT Integrated Global Systems Model (IGSM) using scenarios for 21st century emissions developed by three different groups: intergovernmental (represented by the Intergovernmental Panel on Climate Change), government (represented by the U.S. government Climate Change Science Program) and industry (represented by Royal Dutch Shell plc). In all these scenarios the climate system undergoes substantial changes. By 2100, the CO2 concentration ranges from 470 to 1020 ppm compared to a 2000 level of 365 ppm, the CO2-equivalent concentration of all greenhouse gases ranges from 550 to 1780 ppm in comparison to a 2000 level of 415 ppm, sea level rises by 24 to 56 cm relative to 2000 due to thermal expansion and glacial melt, oceanic acidity changes from a current pH of around 8 to a range from 7.63 to 7.91. The global mean temperature increases by 1.8 to 7.0 degrees C relative to 2000.The IGSM model used here is supported by the U.S. Department of Energy, U.S. Environmental Protection Agency, U.S. National Science Foundation, U.S. National Aeronautics and Space Administration, U.S. National Oceanographic and Atmospheric Administration and the Industry and Foundation Sponsors of the MIT Joint Program on the Science and Policy of Global Change

Modeling North Pacific temperature and pressure changes from coastal tree-ring chronologies

Climate modeling using coastal tree-ring chronologies has yielded the first summer temperature reconstructions for coastal stations along the Gulf of Alaska and the Pacific Northwest. These land temperature reconstructions are strongly correlated with nearby sea surface temperatures, indicating large-scale ocean-atmospheric influences. Significant progress has also been made in modeling winter land temperatures and sea surface temperatures from coastal and shipboard stations. In addition to temperature, the pressure variability center over the central North Pacific Ocean (PAC), which is related to the strength and location of the Aleutian Low pressure system, could be extended using coastal tree rings