The role of plasma wave turbulence in the formation of shock waves in collisionless plasmas

A data set containing measurements for approximately 100 shock crossings was compiled, and plasma wave profiles were plotted in conjunction with magnetic field data. Three emissions analyzed include upstream electron plasma oscillations, ion acoustic noise, and low frequency electromagnetic noise. The data demonstrate that the observed waves are consistent with generation by the kinetic cross-field streaming instability. Reanalysis of shock overshoots prompted by the presence of plasma feet upstream of nominally subcritical shocks leads to the conclusion that no firm evidence exists for a sharp subcritical supercritical transition. Electron plasma oscillations persist up to the ramps of subcritical shocks and begin decaying at the front edge of the feet of supercritical shocks. Their intensity is anticorrelated with the amplitude of the foot ion acoustic noise. Wave measurements support the predicted predominance of lower hybrid-like modes over ion acoustic noise in the production of resistive (plasma) heating. Evidence for variable shock normal angles is seen upstream from nominally quasiparallel shocks. The first cases of very strong electron heating observed at the terrestrial bow shock were discovered

Space Station Freedom solar array panels plasma interaction test facility

The Space Station Freedom Power System will make extensive use of photovoltaic (PV) power generation. The phase 1 power system consists of two PV power modules each capable of delivering 37.5 KW of conditioned power to the user. Each PV module consists of two solar arrays. Each solar array is made up of two solar blankets. Each solar blanket contains 82 PV panels. The PV power modules provide a 160 V nominal operating voltage. Previous research has shown that there are electrical interactions between a plasma environment and a photovoltaic power source. The interactions take two forms: parasitic current loss (occurs when the currect produced by the PV panel leaves at a high potential point and travels through the plasma to a lower potential point, effectively shorting that portion of the PV panel); and arcing (occurs when the PV panel electrically discharges into the plasma). The PV solar array panel plasma interaction test was conceived to evaluate the effects of these interactions on the Space Station Freedom type PV panels as well as to conduct further research. The test article consists of two active solar array panels in series. Each panel consists of two hundred 8 cm x 8 cm silicon solar cells. The test requirements dictated specifications in the following areas: plasma environment/plasma sheath; outgassing; thermal requirements; solar simulation; and data collection requirements

Patient Ventilator Dyssynchrony: Types, Frequency and Patterns in Critically Ill Adults

Patient ventilator dyssynchrony (PVD) occurs frequently, but little is known about the types, frequency and patterns of PVD for longer than 30 minutes. Deeper levels of sedation are associated with PVD. Evaluation of ventilator graphics and the ability to identify PVD should assist clinicians to optimize patient ventilator interactions and promote earlier interventions. The purpose of this study was to identify the different types, frequency and patterns of PVD in critically ill adults and determine the effect of sedation level on PVD. Thirty medical and surgical ICU adult patients were enrolled; 27 were used for analysis. Pressure/time and flow/ time waveform data were collected using the Noninvasive Cardiac Output monitor for up to 90 minutes per subject. Blinded waveform analysis was performed. Sedation level was measured every 20 minutes. A Dyssynchrony Index (DI) and PVD Type Indices were used to describe PVD frequency. Lag analysis was used to detect associated patterns of PVD. PVD occurred during all phases of ventilated breaths and during each of the ventilatory modes used. Heretofore undocumented dyssynchrony in the form of patient gasp PVD, active triggers and combined PVDs were found. The most common type of PVD was Ineffective Trigger (63%), followed by Premature Termination-Flow (17%), Premature Termination (9%), Multiple Trigger (1%), Flow (0.87%) and Delayed Termination (0.09%). The overall frequency of dyssynchronous breaths in the sample was 23% of total breaths analyzed, however 93% of subjects experienced at least one incident of PVD. The overall median DI (Interquartile Range [IQR]) was 4% (1% - 9%) with Ineffective Trigger Index having the highest median index (1.78%). The high DI group (6 subjects, 22%) had a DI (IQR) of 61% (42% - 85%). Seventy seven percent of subjects experienced multiple types of PVD. Premature Termination was followed by Multiple Triggers starting at 3 seconds, but Delayed Termination was followed by Ineffective Triggers, starting at 30 seconds. Clinicians need to recognize PVD, since this is a critical step in evaluating patient ventilator interaction and providing subsequent intervention. PVD interpretation is complex requiring clinicians to clearly understand the operational function of ventilator modes and waveform alterations that occur

DEPLOYED ELECTRONIC MEDICAL RECORD POLICY COMPLIANCE: AN INTRA-DEPARTMENT PRINCIPAL-AGENT PERSPECTIVE

To understand problems related to a policy of implementing a lifelong longitudinal electronic health record (EHR) more fully, this dissertation examines compliance with changes in policy over time. We analyze drivers of compliance with a required electronic medical record (EMR) by hospital clinicians completing the records for deployed service members. This study examines compliance as an outcome of principal-agent (PA) relationships, with the EMR modeled as the measure of success between one level of bureaucratic principal (i.e. medical command) with control over the necessary mechanisms in order to ensure compliance of agents (i.e., medical professionals). Policy compliance is operationalized in three ways: 1) the total number of inpatient EMRs completed; 2) the date on which new records are started; 3) the average number of days to close an inpatient EMR. For each of these dimensions, \u27EMR\u27 refers to what clinicians categorize as treatment for a disease non-battle injury or battle injury. The first independent variable concept for this study is change in the level of information asymmetry between principal and agent, operationalized as the time a superordinate medical command (MEDCOM) is directly in control over hospitals. The second concept is the alignment of goals in order to reduce goal conflict. This is operationalized as a technology upgrade allowing hospital EMR to be used for both implementing the larger EHR as well as in providing real-time clinical notes necessary for the care of patients being evacuated to the next level of medical care. Finally, the concept of principal control mechanisms are operationalized in this study as the introduction of increased monitoring policy and sanctions at the clinician level during hospital transition periods. We use quantitative data in the form of completed electronic medical records and utilize a quasi-experimental research design. The specific design chosen for the study is the interrupted time-series. The population for this study is all United States military service members seen as inpatients in deployed military hospitals directly supporting Operation Iraqi Freedom. The study period is 105 weeks. Overall, this research meets the objectives outlined in Chapter 1 (Introduction). The study examined two important questions regarding clinician compliance with completing EMRs for deployed service members. First, this study addressed if there was a change in policy compliance over time. By conducting an analysis of policy interventions, we established changes in policy compliance. Compliance was defined as the fluctuation in inpatient records started, records completed, and changes in the average time to complete records. Secondly, this study examined what factors influenced the performance of hospital clinicians and how significant these drivers\u27 impact was on record completion. The analysis consisted of graphing the changes over time and examining changes that were most likely due to policy interventions. We further analyzed the changes over time utilizing ANOVA and least squares regression. The results supported many of the hypotheses. Technology upgrades not only led to greater completion rates but also reduced the amount of variation in records completed week to week. The introduction of the monitoring policy also increased both record completions and records started. Finally, sanctioning showed the greatest impact on completing records. This research is important for four reasons. First, this study provides a method to analyze policy implementation at different levels within one federal department. Second, this research enhances the body of knowledge in the inter-disciplinary evaluation of policy implementation. Third, this dissertation examines the role of specific control mechanisms, namely monitoring and sanction, not previously reported in the EHR implementation literature. Finally, this study provides real-world implications for implementing EHR policies in deployed environments. This study determines that the time a MEDCOM is in charge, technology upgrades, monitoring, and sanctions do have an effect on policy compliance but are reliant on the measurement of compliance. As an example, technology upgrades significantly increase the number of EMR completed at hospitals, but they are not statistically significant in increasing or decreasing the number of new encounters started at the hospital. In addition, patient categories influence the significance between the independent and dependent variables

The Effects of \u27Number Talks\u27 on Number Sense in a Second Grade Math Class

The purpose of this study was to evaluate the effectiveness of using ‘Number Talks’ intervention on students’ ability to use number sense to problem-solve and persevere in solving problems within a second-grade math class. The 22 participants were volunteers in my second-grade class. A quasi-experimental design method was used to compare results between a control group and intervention group using a pre-post test design. The intervention group received 15 minutes of ‘Number Talks’ a day for a total of 12 days while the control group participated in traditional daily math activities. Perseverance was measured using a tally chart to record number of strategies students used to solve problems. Written reflections were completed once a week for three weeks to build students’ ability to explain reasoning in writing. Comparison of the mean prepost test scores of the intervention group and control groups indicated no significant differences in the scores. Comparison of the mean post test scores between the intervention and control groups indicated no significant differences in the scores. However, the dis-aggregated data showed some positive results in individual cases and improvements with written responses

Development & Testing of Novel Atmospheric Chemistry Technologies

Atmospheric aerosols play an important role in global atmospheric chemistry and climate and have a detrimental impact on human health. Advancements in measurement technologies allow for better monitoring of atmospheric composition and dynamics, creating better predictive models and understanding of atmospheric chemistry and physics. Gas and particle atmospheric oxidation is poorly understood. In order to create a better understanding of atmospheric oxidation, the following equipment was developed: 1) a Potential Aerosol Mass: PAM) flow reaction chamber was developed to create reproducible steady-state oxidation of organic species in a controlled laboratory setting, 2) a custom combustion chamber for introduction of realistic single source samples, and 3) a Thermal desorption Aerosol Gas chromatograph: TAG) for hourly speciation of hundreds of semi-volatile and non-volatile organic compounds. Development and construction of the Combustion Chamber, PAM Chamber, and TAG system are discussed as well as preliminary applications of this equipment. These instruments allow for the study of primary organic aerosol: POA) and secondary organic aerosol: SOA) formation. Due to the lack of knowledge concerning organic aerosol source chemical profiles and subsequent chemical evolution in the atmosphere, these studies are crucial for furthering the understanding of atmospheric chemistry and in developing accurate atmospheric models

A review of dietary monitoring applications and eating disorder/disordered eating symptomatology

Eating disorders are among the deadliest mental illnesses in the United States. Given their high prevalence and low treatment rates, mitigating risk exposure is necessary for prevention. Dietary monitoring applications are highly popular self-monitoring tools that can inform dietary patterns and improve weight loss efficacy. However, they can also serve as a means for those with body preoccupation to restrict and possibly exacerbate disordered symptomatology. A literature search was conducted to identify research regarding the usage of dietary monitoring applications and eating disorder/disordered eating symptomatology. Twelve articles met inclusion criteria and are discussed in the review. An association between the use of apps to self-monitor dietary intake and disordered eating behaviors were consistently reported in observational studies. No impact on the use of these apps and validated assessments of eating disorder/disordered eating symptomatology were indicated in experimental studies on low-risk populations. However, both limitations and qualitative analysis suggest that continued research with improved methodology is necessary. Some principal issues within methodology include sampling issues, minimal risk exposure, and unrealistic use case scenarios. With eating disorder prevalence and dietary monitoring app use rising, future research to investigate the associations and any temporal effects on eating disorder/disordered eating symptomatology is imperative to inform researchers and clinicians

Contemporary Trends in the Band\u27s Instrumentation and Literature

No abstract provided by author