397 results on '"Epstein, Michael"'
Search Results
2. Content Validation of the Behavioral and Emotional Rating Scale–3rd Edition: Strength-Based Interview.
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Pierce, Corey D., Epstein, Michael H., and Wood, Matthew D.
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COLLEGE teachers , *CHILD behavior , *INTERVIEWING , *SURVEYS , *PSYCHOMETRICS , *EMOTIONS , *SOCIAL services ,RESEARCH evaluation - Abstract
Strength-based assessment has achieved acceptance from educational, mental health, and social service professionals as a means to measuring emotional and behavioral strengths of children. Several standardized, norm-referenced tests have been developed to assess these strengths; however, the primary mode of assessment is via informal interviews of parents and caregivers. In many cases, these interviews lack psychometric support, including basic validity and reliability. The purpose of this study was to document the multistep process used to establish the content validity of a newly developed instrument: Behavioral and Emotional Rating Scale: Strength-Based Interview. Specifically, the results of a survey of 40 U.S. professional mental health staff and educators are described where respondents rated the importance of interview questions to the construct of strength-based assessment. The findings of the survey as well as the 18 items deemed most important are reported. Research limitations, future research, and implications for mental health and educational professionals are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. A 22-Year Cross-Sectional Cohort Study of the Emotional and Behavioral Characteristics of Students With Emotional Disturbance.
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Epstein, Michael H., Cullinan, Douglas, Lambert, Matthew C., Kauffman, James M., Katsiyannis, Antonis, and Mason, W. Alex
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TEACHER evaluation , *CROSS-sectional method , *COHORT analysis , *CHARACTERISTIC functions , *CHILD behavior - Abstract
The present study was conducted to determine whether the problem characteristics of U.S. students school-identified with emotional disturbance (ED) have changed over two decades. We used data from a teacher rating instrument designed to measure the five problem characteristics of ED, as stated in its Individuals with Disabilities Education Act (IDEA) definition. These data were collected in the process of norming the instrument for 1998 and again for 2020. Comparison of the 1998 and 2020 students school-identified with ED showed that the 1998 group had significantly more problematic functioning on two characteristics, namely, Relationship Problems and Inappropriate Behavior, but no more problematic differences on Inability to Learn, Unhappiness or Depression, and Physical Symptoms or Fears. In addition, analyses of selected items gave more context to the main results. Study limitations, future research, and implications are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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4. Ensemble Statistics Can Be Available before Individual Item Properties: Electroencephalography Evidence Using the Oddball Paradigm.
- Author
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Epstein, Michael L. and Emmanouil, Tatiana A.
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ELECTROENCEPHALOGRAPHY , *TIME perception , *ECONOMIC stimulus , *MULTIVARIATE analysis , *STATISTICS - Abstract
Behavioral studies have shown that statistical properties of object groups are perceived accurately with brief exposure durations. This finding motivated the hypothesis that ensemble perception occurs rapidly in vision. However, the precise timing of ensemble perception remains unclear. Here, we used the superior temporal resolution of electroencephalography to directly compare the timing of ensemble processing to that of individual object processing. The P3b was chosen as a particular component of interest, as it is thought to measure the latency of stimulus evaluation. Participants performed a simple "oddball" task in which sets of 51 lines with varied orientations sequentially flashed briefly on the display. In these sequences, there was a 20% chance of an individual oddball, wherein one marked object tilted clockwise, and a 20% chance of an ensemble oddball, wherein the average orientation of the set tilted clockwise. In counterbalanced blocks, participants were instructed to respond to either individual or ensemble oddballs. ERP analysis was performed to test the timing of this processing. At parietal electrodes, P3b components were found for both individual and ensemble oddballs. Ensemble P3b components were found to occur significantly earlier than individual P3b components, as measured with both 50% area latency and 50% onset latency. Using multivariate pattern analysis, ensemble oddball trials were classifiable from standard trials significantly earlier in their timecourse than individual oddball trials. Altogether, these results provide compelling evidence that ensemble perception occurs rapidly and that ensemble properties can be available earlier than individual object properties. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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5. Ensemble Statistics Can Be Available before Individual Item Properties: Electroencephalography Evidence Using the Oddball Paradigm.
- Author
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Epstein, Michael L. and Emmanouil, Tatiana A.
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ELECTROENCEPHALOGRAPHY , *TIME perception , *ECONOMIC stimulus , *MULTIVARIATE analysis , *STATISTICS - Abstract
Behavioral studies have shown that statistical properties of object groups are perceived accurately with brief exposure durations. This finding motivated the hypothesis that ensemble perception occurs rapidly in vision. However, the precise timing of ensemble perception remains unclear. Here, we used the superior temporal resolution of electroencephalography to directly compare the timing of ensemble processing to that of individual object processing. The P3b was chosen as a particular component of interest, as it is thought to measure the latency of stimulus evaluation. Participants performed a simple "oddball" task in which sets of 51 lines with varied orientations sequentially flashed briefly on the display. In these sequences, there was a 20% chance of an individual oddball, wherein one marked object tilted clockwise, and a 20% chance of an ensemble oddball, wherein the average orientation of the set tilted clockwise. In counterbalanced blocks, participants were instructed to respond to either individual or ensemble oddballs. ERP analysis was performed to test the timing of this processing. At parietal electrodes, P3b components were found for both individual and ensemble oddballs. Ensemble P3b components were found to occur significantly earlier than individual P3b components, as measured with both 50% area latency and 50% onset latency. Using multivariate pattern analysis, ensemble oddball trials were classifiable from standard trials significantly earlier in their timecourse than individual oddball trials. Altogether, these results provide compelling evidence that ensemble perception occurs rapidly and that ensemble properties can be available earlier than individual object properties. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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- View/download PDF
6. The outlier paradox: The role of iterative ensemble coding in discounting outliers.
- Author
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Epstein, Michael L., Quilty-Dunn, Jake, Mandelbaum, Eric, and Emmanouil, Tatiana A.
- Abstract
Ensemble perception--the encoding of objects by their group properties--is known to be resistant to outlier noise. However, this resistance is somewhat paradoxical: how can the visual system determine which stimuli are outliers without already having derived statistical properties of the ensemble? A simple solution would be that ensemble perception is not a simple, one-step process; instead, outliers are detected through iterative computations that identify items with high deviance from the mean and reduce their weight in the representation over time. Here we tested this hypothesis. In Experiment 1, we found evidence that outliers are discounted from mean orientation judgments, extending previous results from ensemble face perception. In Experiment 2, we tested the timing of outlier rejection by having participants perform speeded judgments of sets with or without outliers. We observed significant increases in reaction time (RT) when outliers were present, but a decrease compared to no-outlier sets of matched range suggesting that range alone did not drive RTs. In Experiment 3 we tested the timing by which outlier noise reduces over time. We presented sets for variable exposure durations and found that noise decreases linearly over time. Altogether these results suggest that ensemble representations are optimized through iterative computations aimed at reducing noise. The finding that ensemble perception is an iterative process provides a useful framework for understanding contextual effects on ensemble perception. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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7. Co-production of Monosaccharides and Hydrochar from Green Macroalgae Ulva (Chlorophyta) sp. with Subcritical Hydrolysis and Carbonization.
- Author
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Greiserman, Semion, Epstein, Michael, Chemodanov, Alexander, Steinbruch, Efraim, Prabhu, Meghanath, Guttman, Lior, Jinjikhashvily, Gabriel, Shamis, Olga, Gozin, Michael, Kribus, Abraham, and Golberg, Alexander
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MONOSACCHARIDES , *ULVA , *CARBONIZATION , *GREEN algae , *HYDROLYSIS , *GREEN technology - Abstract
Subcritical water hydrolysis and carbonization of the biomass are an emerging green technology for seaweed biomass processing. In this work, a novel approach for co-generation of two energy streams from seaweed biomass (fermentable sugars and solid hydrochar) with subcritical water from a green macroalgae Ulva sp. was developed. It was found that for the released of glucose, xylose, rhamnose, fructose, and galactose, the process temperature is the most significant parameter, followed by salinity, solid load, and treatment time. For the formation of fermentation inhibitor 5-hydroxymethylfurfural (5-HMF), temperature also was the most important parameter, followed by residence time, salinity, and solid load. The optimum parameters for maximal release of total sugars under minimum formation of 5-HMF were 170 °C (800 kPa abs.), 5% solid loading, 40 min residence time, and 100% salinity. The hydrochar yield was 19.4% and hydrochar high heating value was 20.2 ± 1.31 MJ kg−1. These results provide new detailed information on the subcritical hydrolysis and carbonization of Ulva sp. biomass and show co-production of fermentable monosaccharides and hydrochar. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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8. Michael D. Scott.
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Epstein, Michael M.
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LAW teachers , *FIRST responders , *DIGITAL technology , *COMPUTER laws , *PUBLIC transit - Abstract
The Journal of International Media & Entertainment Law's Volume 10 is dedicated to the memory of Southwestern Law Professor Michael D. Scott, who passed away at the age of 77. Professor Scott had a successful career as a tech lawyer and was a respected member of the Southwestern faculty. He was known for his expertise in computer law and his dedication to his students. Professor Scott's commitment to his colleagues was demonstrated during a terrorist attack in London when he walked for two hours to reach his class. He will be greatly missed by the Southwestern faculty. [Extracted from the article]
- Published
- 2023
9. Editor's Note.
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Epstein, Michael M.
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SOCIAL media , *WAR , *DIGITAL technology , *CENSORSHIP , *INTERNATIONAL conflict - Abstract
The article discusses the armed conflicts between Armenia and Azerbaijan over Nagorno-Karabakh, which are seen as a result of a long-standing ethnic and geopolitical dispute. It also mentions other territorial conflicts in former Soviet Republics, such as Georgia, Chechnya, Crimea, and Ukraine. The Journal of International Media & Entertainment Law organized a symposium on the role of media institutions, government censorship, and social media speech norms in post-Soviet-era disputes. The issue includes articles by Dr. András Koltay on the European Union's ban on Russian media, Dr. Andrei Richter on propaganda for war in the digital era, and Dr. Andrej Skolkay on misinformation and disinformation in regional conflicts involving Russia. [Extracted from the article]
- Published
- 2023
10. Mass exchange between light metal layer and oxidic layer in lower plenum corium pool for a high steel content condition.
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Zhou, Quan and Epstein, Michael
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LIGHT metals , *INTERFACES (Physical sciences) , *MASS transfer , *LIQUID-liquid interfaces , *STEEL alloys - Abstract
Highlights • Interfacial equilibrium compositions are studied with a convective mass transfer model. • A lighter metal phase is supported at the interface for high steel content corium. • Mutual mass transfer is supported for high steel content corium. • Metal layer is not continuously thinned to challenge reactor vessel integrity. Abstract In-vessel retention is a severe accident strategy adopted in several PWR designs. The success of this strategy is subject to whether the mass transfer between the light metal layer and oxidic layer is mutual or one-way. The one-way mass transfer, which is due to heavy metal generated at the metal/oxide interface, causes the light metal layer to continuously lose its mass. The thinning process may challenge the lower plenum integrity. A steady-state model has been developed and reported in this paper to evaluate which mode the mass transfer between the light metal and oxidic layers is. The objective of the model is to assess the potential for heavy metal generation at the metal/oxide interface. The model is based on the idealization of a thin stationary interface through which mass is transferred by convective-diffusion processes in the light metal layer and in the oxidic layer. That is, it is conservatively assumed that the crust formed between the light metal layer and the oxidic layer is sufficiently permeable that it offers no resistance to the interfacial mass transfer. The equilibrium compositions at both sides of the liquid-liquid interface (with the crust ignored) are assumed to follow a simplified phase diagram of U-O-Zr-steel at a high temperature (Salay and Fichot, 2004). Based on the model calculations, and even considering the uncertainty in the value of a key dimensionless parameter, it is concluded that heavy metal formation at the interface is unlikely in a lower plenum pool of high steel content. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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11. A Novel Delivery System of Peppermint Oil Is an Effective Therapy for Irritable Bowel Syndrome Symptoms.
- Author
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Cash, Brooks, Epstein, Michael, Shah, Syed, Cash, Brooks D, Epstein, Michael S, and Shah, Syed M
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IRRITABLE colon treatment , *PEPPERMINT oil , *TREATMENT effectiveness , *DRUG delivery systems , *SYMPTOMS , *PLACEBOS , *THERAPEUTICS , *COMPARATIVE studies , *IRRITABLE colon , *RESEARCH methodology , *MEDICAL cooperation , *PARASYMPATHOLYTIC agents , *RESEARCH , *EVALUATION research , *VEGETABLE oils , *RANDOMIZED controlled trials , *BLIND experiment - Abstract
Background: Peppermint oil (PO) has shown promise as an IBS therapy, but previous trials have demonstrated variable efficacy and tolerability results.Aims: To evaluate the efficacy and tolerability of a novel formulation of PO designed for sustained release in the small intestine in patients with IBS-M and IBS-D.Methods: This is a 4-week, randomized, double-blind, placebo-controlled clinical trial of PO or identical placebo 3 times daily in patients fulfilling Rome III criteria for IBS-M or IBS-D. The primary endpoint was the change from baseline in the Total IBS Symptom Score (TISS) after 4 weeks of treatment.Results: Seventy-two patients (mean age 40.7 years, 75 % female, 77.8 % white) were randomized to PO (n = 35) or placebo (n = 37). At 4 weeks, PO was associated with a 40 % reduction in the TISS from baseline (mean change -1.16, SD ± 0.807), superior to the 24.3 % decrease (mean change -0.70, SD ± 0.737) observed with placebo (P = 0.0246). The decrease in the TISS of 19.6 % (mean change -0.55, SD ± 0.613) in the PO group at 24 h was also significantly larger than placebo (-10.3 %, mean change -0.27, SD ± 0.342) (P = 0.0092). At trial completion, patients in the PO group experienced greater improvement in multiple individual gastrointestinal symptoms as well as in severe or unbearable symptoms, compared to placebo. PO was well tolerated with few adverse events.Conclusions: A novel PO formulation designed for sustained release in the small intestine is a safe, effective treatment capable of providing rapid relief of IBS symptoms. [ABSTRACT FROM AUTHOR]- Published
- 2016
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12. A turbulent diffusion model of Rayleigh-Taylor mixing.
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Epstein, Michael, Paik, Chan Y., Plys, Martin G., and Lee, Sung Jin
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TURBULENT diffusion (Meteorology) , *RAYLEIGH-Taylor instability , *MIXING , *FLUID dynamics , *POLYNOMIALS , *COMPUTER simulation - Abstract
A simple turbulent diffusion model is described for predicting late term mixing due to Rayleigh-Taylor instability at an interface that initially separates two semi-infinite regions of fluid of different densities. The one-dimensional, transient species conservation equation is combined with an available vertical dispersion equation which relates the turbulent diffusivity to the local density gradient and a characteristic mixing length. The similarity solution of the species conservation equation yields the well-known long time result for the vertical extent of the mixing region and shows that the dimensionless growth constant that appears in the mixing thickness equation is simply a measure of the size of the characteristic mixing length. A simple polynomial relation is derived for the heavy fluid volume fraction profile within the mixing region which is in close agreement with the profile obtained from a previously reported numerical simulation of Rayleigh-Taylor mixing. It is demonstrated how the model can be readily applied to predict Rayleigh-Taylor mixing in a finite fluid region between top and bottom boundaries. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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13. Performance assessment of concentrated solar power plants based on carbon and hydrogen fuel cells.
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Díaz, Elena, Epstein, Michael, Romero, Manuel, and González-Aguilar, José
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SOLAR power plants , *FUEL cells , *ELECTRIC power production , *CHEMICAL decomposition , *THERMODYNAMIC equilibrium - Abstract
In spite of the recent success on the implementation of Concentrating Solar Power (CSP), still this technology needs a substantial enhancement to achieve competitiveness. This paper provides thorough insight after previous analyses on an alternative concept for higher efficiency CSP systems based on the replacement of the power block by an electrochemical conversion system. Concentrating solar energy is herewith used to decompose methane into hydrogen and carbon, which are used in hydrogen and carbon fuel cells for electricity generation. This approach envisages modular, efficient and flexible generation plants. Dispatchability can be achieved by storing the solid carbon. Solar-to-electricity efficiency was calculated assuming thermodynamic equilibrium composition and experimental data available from literature, and compared with those of conventional power generation systems and commercial CSP plants. It is concluded that this new-generation CSP concept is potentially able to produce power more efficiently than the current state-of-the art solar thermal power plants. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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14. Improvement in mismatch negativity generation during d-serine treatment in schizophrenia: Correlation with symptoms.
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Kantrowitz, Joshua T., Epstein, Michael L., Lee, Migyung, Lehrfeld, Nayla, Nolan, Karen A, Shope, Constance, Petkova, Eva, Silipo, Gail, and Javitt, Daniel C.
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SCHIZOPHRENIA treatment , *SERINE , *METHYL aspartate receptors , *PLACEBOS , *CLINICAL trials , *THERAPEUTICS - Abstract
Background: Deficits in N-methyl-d-aspartate-type (NMDAR) function contribute to symptoms and cognitive dysfunction in schizophrenia. The efficacy of NMDAR agonists in the treatment of persistent symptoms of schizophrenia has been variable, potentially reflecting limitations in functional target engagement. We recently demonstrated significant improvement in auditory mismatch negativity (MMN) with once-weekly treatment with d-serine, a naturally occurring NMDAR glycine-site agonist. This study investigates effects of continuous (daily) NMDAR agonists in schizophrenia/schizoaffective disorder.Methods: Primary analysis was on MMN after double-blind crossover (60mg/kg/d, n=16, 6weeks) treatment with d-serine/placebo. Secondary measures included clinical symptoms, neurocognition, and the effects of open-label (30-120mg/kg/d, n=21) d-serine and bitopertin/placebo (10mg, n=29), a glycine transport inhibitor.Results: Double-blind d-serine treatment led to significant improvement in MMN frequency (p=0.001, d=2.3) generation and clinical symptoms (p=0.023, d=0.80). MMN frequency correlated significantly with change in symptoms (r=-0.63, p=0.002) following co-variation for treatment type. d-Serine treatment led to a significant, large effect size increase vs. placebo in evoked α-power in response to standards (p=0.036, d=0.81), appearing to normalize evoked α power relative to previous findings with controls. While similar results were seen with open-label d-serine, no significant effects of bitopertin were observed for symptoms or MMN.Conclusions: These findings represent the first randomized double-blind placebo-controlled study with 60mg/kg d-serine in schizophrenia, and are consistent with meta-analyses showing significant effects of d-serine in schizophrenia. Results overall support suggest that MMN may have negative, as well as positive, predictive value in predicting efficacy of novel compounds.Clinical Trials Registration: Clinicaltrials.gov: NCT00322023/NCT00817336 (d-serine); NCT01116830 (bitopertin). [ABSTRACT FROM AUTHOR]- Published
- 2018
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15. Ensemble coding remains accurate under object and spatial visual working memory load.
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Epstein, Michael and Emmanouil, Tatiana
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VISUAL perception , *VISUAL memory , *STIMULUS & response (Psychology) , *SHORT-term memory , *ACCURACY - Abstract
A number of studies have provided evidence that the visual system statistically summarizes large amounts of information that would exceed the limitations of attention and working memory (ensemble coding). However the necessity of working memory resources for ensemble coding has not yet been tested directly. In the current study, we used a dual task design to test the effect of object and spatial visual working memory load on size averaging accuracy. In Experiment 1, we tested participants' accuracy in comparing the mean size of two sets under various levels of object visual working memory load. Although the accuracy of average size judgments depended on the difference in mean size between the two sets, we found no effect of working memory load. In Experiment 2, we tested the same average size judgment while participants were under spatial visual working memory load, again finding no effect of load on averaging accuracy. Overall our results reveal that ensemble coding can proceed unimpeded and highly accurately under both object and spatial visual working memory load, providing further evidence that ensemble coding reflects a basic perceptual process distinct from that of individual object processing. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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16. Thermo-electro-chemical storage (TECS) of solar energy.
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Wenger, Erez, Epstein, Michael, and Kribus, Abraham
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SOLAR power plants , *THERMOELECTRIC effects , *ENERGY storage , *ZINC ions , *STORAGE batteries - Abstract
A new approach for solar electricity generation and storage is proposed, based on the concept of thermally regenerative batteries. Concentrated sunlight is used for external thermo-chemical charging of a flow battery, and electricity is produced by conventional electro-chemical discharge of the battery. The battery replaces the steam turbine, currently used in commercial concentrated solar power (CSP) plants, potentially leading to much higher conversion efficiency. This approach offers potential performance, cost and operational advantages compared to existing solar technologies, and to existing storage solutions for management of an electrical grid with a significant contribution of intermittent solar electricity generation. Here we analyze the theoretical conversion efficiency for new thermo-electro-chemical storage (TECS) plant schemes based on the electro-chemical systems of sodium-sulfur (Na-S) and zinc-air. The thermodynamic upper limit of solar to electricity conversion efficiency for an ideal TECS cycle is about 60% for Na-S at reactor temperature of 1550 K, and 65% for the zinc-air system at 1750 K, both under sunlight concentration of 3000. A hybrid process with carbothermic reduction in the zinc-air system reaches 60% theoretical efficiency at the more practical conditions of reaction temperature <1200 K and concentration <1000. Practical TECS plant efficiency, estimated from these upper limits, may then be much higher compared to existing solar electricity technologies. The technical and economical feasibility of the proposed cycle are also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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17. Neurophysiological mechanisms of cortical plasticity impairments in schizophrenia and modulation by the NMDA receptor agonist D-serine.
- Author
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Kantrowitz, Joshua T., Epstein, Michael L., Beggel, Odeta, Rohrig, Stephanie, Lehrfeld, Jonathan M., Revheim, Nadine, Lehrfeld, Nayla P., Reep, Jacob, Parker, Emily, Silipo, Gail, Ahissar, Merav, and Javitt, Daniel C.
- Subjects
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METHYL aspartate receptors , *SERINE , *SCHIZOPHRENIA , *NEUROPHYSIOLOGY , *NEUROPLASTICITY , *BRAIN physiology , *DRUG therapy for psychoses , *AUDITORY evoked response , *CELL receptors , *COMPARATIVE studies , *LONGITUDINAL method , *RESEARCH methodology , *MEDICAL cooperation , *PSYCHOSES , *RESEARCH , *RESEARCH funding , *WORD deafness , *EVALUATION research , *RANDOMIZED controlled trials , *EXCITATORY amino acid agonists ,DRUG therapy for schizophrenia - Abstract
Schizophrenia is associated with deficits in cortical plasticity that affect sensory brain regions and lead to impaired cognitive performance. Here we examined underlying neural mechanisms of auditory plasticity deficits using combined behavioural and neurophysiological assessment, along with neuropharmacological manipulation targeted at the N-methyl-D-aspartate type glutamate receptor (NMDAR). Cortical plasticity was assessed in a cohort of 40 schizophrenia/schizoaffective patients relative to 42 healthy control subjects using a fixed reference tone auditory plasticity task. In a second cohort (n = 21 schizophrenia/schizoaffective patients, n = 13 healthy controls), event-related potential and event-related time-frequency measures of auditory dysfunction were assessed during administration of the NMDAR agonist d-serine. Mismatch negativity was used as a functional read-out of auditory-level function. Clinical trials registration numbers were NCT01474395/NCT02156908 Schizophrenia/schizoaffective patients showed significantly reduced auditory plasticity versus healthy controls (P = 0.001) that correlated with measures of cognitive, occupational and social dysfunction. In event-related potential/time-frequency analyses, patients showed highly significant reductions in sensory N1 that reflected underlying impairments in θ responses (P < 0.001), along with reduced θ and β-power modulation during retention and motor-preparation intervals. Repeated administration of d-serine led to intercorrelated improvements in (i) auditory plasticity (P < 0.001); (ii) θ-frequency response (P < 0.05); and (iii) mismatch negativity generation to trained versus untrained tones (P = 0.02). Schizophrenia/schizoaffective patients show highly significant deficits in auditory plasticity that contribute to cognitive, occupational and social dysfunction. d-serine studies suggest first that NMDAR dysfunction may contribute to underlying cortical plasticity deficits and, second, that repeated NMDAR agonist administration may enhance cortical plasticity in schizophrenia. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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18. Toward a Differential Diagnosis of Hidden Hearing Loss in Humans.
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Liberman, M. Charles, Epstein, Michael J., Cleveland, Sandra S., Wang, Haobing, and Maison, Stéphane F.
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DIAGNOSIS of deafness , *HUMAN abnormalities , *NEURODEGENERATION , *DIFFERENTIAL diagnosis , *ELECTROCOCHLEOGRAPHY , *HEARING levels , *HIDDEN hearing loss - Abstract
Recent work suggests that hair cells are not the most vulnerable elements in the inner ear; rather, it is the synapses between hair cells and cochlear nerve terminals that degenerate first in the aging or noise-exposed ear. This primary neural degeneration does not affect hearing thresholds, but likely contributes to problems understanding speech in difficult listening environments, and may be important in the generation of tinnitus and/or hyperacusis. To look for signs of cochlear synaptopathy in humans, we recruited college students and divided them into low-risk and high-risk groups based on self-report of noise exposure and use of hearing protection. Cochlear function was assessed by otoacoustic emissions and click-evoked electrocochleography; hearing was assessed by behavioral audiometry and word recognition with or without noise or time compression and reverberation. Both groups had normal thresholds at standard audiometric frequencies, however, the high-risk group showed significant threshold elevation at high frequencies (10–16 kHz), consistent with early stages of noise damage. Electrocochleography showed a significant difference in the ratio between the waveform peaks generated by hair cells (Summating Potential; SP) vs. cochlear neurons (Action Potential; AP), i.e. the SP/AP ratio, consistent with selective neural loss. The high-risk group also showed significantly poorer performance on word recognition in noise or with time compression and reverberation, and reported heightened reactions to sound consistent with hyperacusis. These results suggest that the SP/AP ratio may be useful in the diagnosis of “hidden hearing loss” and that, as suggested by animal models, the noise-induced loss of cochlear nerve synapses leads to deficits in hearing abilities in difficult listening situations, despite the presence of normal thresholds at standard audiometric frequencies. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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19. A Statistical Approach for Rare-Variant Association Testing in Affected Sibships.
- Author
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Epstein, Michael P., Duncan, Richard, Ware, Erin B., Jhun, Min A., Bielak, Lawrence F., Zhao, Wei, Smith, Jennifer A., Peyser, Patricia A., Kardia, Sharon L.R., and Satten, Glen A.
- Subjects
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HUMAN genetic variation , *GENETIC testing , *NUCLEOTIDE sequencing , *FAMILIAL diseases , *DISEASE susceptibility - Abstract
Sequencing and exome-chip technologies have motivated development of novel statistical tests to identify rare genetic variation that influences complex diseases. Although many rare-variant association tests exist for case-control or cross-sectional studies, far fewer methods exist for testing association in families. This is unfortunate, because cosegregation of rare variation and disease status in families can amplify association signals for rare variants. Many researchers have begun sequencing (or genotyping via exome chips) familial samples that were either recently collected or previously collected for linkage studies. Because many linkage studies of complex diseases sampled affected sibships, we propose a strategy for association testing of rare variants for use in this study design. The logic behind our approach is that rare susceptibility variants should be found more often on regions shared identical by descent by affected sibling pairs than on regions not shared identical by descent. We propose both burden and variance-component tests of rare variation that are applicable to affected sibships of arbitrary size and that do not require genotype information from unaffected siblings or independent controls. Our approaches are robust to population stratification and produce analytic p values, thereby enabling our approach to scale easily to genome-wide studies of rare variation. We illustrate our methods by using simulated data and exome chip data from sibships ascertained for hypertension collected as part of the Genetic Epidemiology Network of Arteriopathy (GENOA) study. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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20. Biosimilars: The Need, The Challenge, The Future: The FDA Perspective.
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Epstein, Michael S, Ehrenpreis, Eli D, and Kulkarni, Prasad M
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BIOLOGICALS , *MEDICAL technology , *GENERIC drugs , *DRUG approval - Abstract
OBJECTIVES:This article summarizes the brief history of the biosimilars industry, the FDA's regulations and guidance for biosimilars development, and the issues and challenges facing developers and regulators in bringing biosimilars to market.METHODS:Current literature, regulations, and FDA guidance documents were summarized and interpreted to define biosimilars and to present their financial and clinical implications.RESULTS:Some biologic agents that will lose patent protection during the next few years may be replaced with lower cost follow-on biologics. However, unlike generic drugs, biosimilars may be structurally and functionally different from the reference product they are designed to resemble. The FDA has yet to approve any agent via the abbreviated licensure pathway for biosimilars that was passed as part of the Affordable Care Act. The FDA has issued new guidance describing processes by which manufacturers may demonstrate either biosimilarity or interchangeability with an FDA-approved biologic agent, which is required for abbreviated licensure. Biosimilars approved in Europe consist of relatively small molecules; complex large-molecule biosimilars could be subjected to a rigorous and prolonged FDA approval process, which would defeat attempts to develop lower-cost versions of biologic drugs.CONCLUSIONS:Biosimilar development is a consequence of the financial success of biologic therapies and their eventual patent expiration. The pharmaceutical industry must now develop complex biosimilars that resemble FDA-approved biologic agents and invent analytical tools and end points to demonstrate similarity to regulatory authorities. Already in development is a new wave of 'biobetter' or 'biosuperior' drugs that mimic but also improve upon a biologic drug's chemistry, formulation, or delivery. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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21. Differences in Emotional and Behavioral Problems of Students over Time: A 22-Year Cross-Sectional Cohort Study.
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Mason, W. Alex, Lambert, Matthew C., and Epstein, Michael H.
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EMOTIONAL problems of children , *BEHAVIOR disorders in children , *STRUCTURAL equation modeling , *COHORT analysis , *CROSS-sectional method , *FEAR - Abstract
Levels of emotional and behavioral problems in children and adolescents demonstrate secular changes over time, warranting ongoing investigation. Prior studies examining secular trends in a range of such problems have been conducted in the U.S. and internationally. Research in this area generally has not fully considered the school setting. This study compared emotional and behavioral problems across two cohorts of students in the U.S. assessed over a 22-year time period as part of measurement development efforts for the Scales for Assessing Emotional Disturbance Rating Scale (SAED-RSRS; Epstein et al., 2020). Specifically, analyses drew from data collected via teacher report on matched cohorts of students for the 1998 (data collected from 1996 to 1997; n = 1,148) and 2020 (data collected from 2016 to 2018; n = 1,148) editions of the SAED-RS. After establishing measurement invariance across cohorts and testing for gender differences, structural equation modeling revealed statistically significant cohort mean differences on two of the five factors of the SAED-RS, suggesting increases over time in Inability to Learn (β = 0.09, p =.024) and Physical Symptoms and Fears (β = 0.14, p =.005) that were comparable for girls and boys. There were no statistically significant differences on the remaining factors: Relationship Problems, Inappropriate Behavior, and Unhappiness/Depression. Supplemental item-level tests revealed differences on 8 of the 39 SAED-RS items. Findings suggest increases in specific problem areas that could benefit from ongoing monitoring and targeted interventions to support contemporary students. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
22. Characteristics of emotional disturbance of female and male students in elementary, middle, and high school.
- Author
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Cullinan, Douglas, Lambert, Matthew C., and Epstein, Michael H.
- Subjects
- *
HIGH schools , *ANALYSIS of covariance , *TEACHER evaluation , *PSYCHOLOGY of teachers , *STUDENTS with disabilities , *SPECIAL education teachers , *PHYSICAL education teachers - Abstract
Provide data on the five characteristics of emotional disturbance (ED). For 503 students with ED and 2016 without disabilities, teachers rated the characteristics (Inability to Learn; Relationship Problems; Inappropriate Behavior; Unhappiness or Depression; Physical Symptoms or Fears), plus Socially Maladjusted. We applied a 2 (ED, without disabilities) × 2 (female, male) × 3 (elementary, middle, high school) covariance analysis, with follow‐up comparisons. Students with ED showed greater problems than students without disabilities on all five characteristics, and Socially Maladjusted. On Inability to Learn, among students with ED genders did not differ at elementary but males had greater problems at middle school. On Inappropriate Behavior and Physical Symptoms or Fears, students with ED varied across school levels but students without disabilities did not. All five characteristics discriminated students with ED from those without disabilities. Differences between genders and school levels varied across characteristics. Practitioner points: On all five IDEA characteristics of emotional disturbance (ED), students with ED show significantly more serious problems than their peers with no disabilities.Assessment of all five characteristics of ED can help the multidisciplinary team determine whether a student qualifies as ED.Assessment of the five characteristics can also suggest directions for school intervention. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
23. The Cost-Effectiveness of New York City’s Safe Routes to School Program.
- Author
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Muennig, Peter A., Epstein, Michael, Guohua Li, and DiMaggio, Charles
- Subjects
- *
TRAFFIC safety , *DEATH , *WOUNDS & injuries , *METROPOLITAN areas , *CHILDREN'S accident prevention , *COMPUTER simulation , *COST effectiveness , *INVESTMENTS , *RESEARCH funding , *SPATIAL behavior , *STUDENTS , *PREDICTIVE tests , *QUALITY-adjusted life years , *DESCRIPTIVE statistics , *ECONOMICS , *PREVENTION - Abstract
Objective. We evaluated the cost-effectiveness of a package of roadway modifications in New York City funded under the Safe Routes to School (SRTS) program. Methods. We used a Markov model to estimate long-term impacts of SRTS on injury reduction and the associated savings in medical costs, lifelong disability, and death. Model inputs included societal costs (in 2013 US dollars) and observed spatiotemporal changes in injury rates associated with New York City’s implementation of SRTS relative to control intersections. Structural changes to roadways were assumed to last 50 years before further investment is required. Therefore, costs were discounted over 50 consecutive cohorts of modified roadway users under SRTS. Results. SRTS was associated with an overall net societal benefit of $230 million and 2055 quality-adjusted life years gained in New York City. Conclusions. SRTS reduces injuries and saves money over the long run. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
24. Emotional and Behavioral Screener: Test–Retest Reliability, Inter-Rater Reliability, and Convergent Validity.
- Author
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Nordness, Philip D., Epstein, Michael H., Cullinan, Douglas, and Pierce, Corey D.
- Published
- 2014
- Full Text
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25. Emotional and Behavioral Screener: Test–Retest Reliability, Inter-Rater Reliability, and Convergent Validity.
- Author
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Nordness, Philip D., Epstein, Michael H., Cullinan, Douglas, and Pierce, Corey D.
- Subjects
- *
CHILD psychopathology , *CHILD behavior , *SCALE analysis (Psychology) , *TEENAGERS' conduct of life , *INTER-observer reliability , *RESEARCH methodology evaluation , *COLLEGE teacher attitudes , *DESCRIPTIVE statistics ,RESEARCH evaluation - Abstract
The Emotional and Behavioral Screener (EBS) is a universal screening instrument designed to identify students whose excessive problem behaviors put them at risk of the education disability category of emotional disturbance (ED). This article reports findings from three studies that address the reliability and validity of the EBS. Studies 1 and 2 examined the test–retest and inter-rater reliability of the EBS. Study 3 investigated the convergent validity of the EBS by comparing it to the Behavioral and Emotional Screening System. The results from these studies support the reliability and validity of the EBS as a universal screening instrument for identifying students who may be at risk of ED or those who may require a greater degree of monitoring, decision-making, formal assessment, or intervention to restore normal behavior functioning and prevent identification as ED. Implications, research limitations, and future research needs are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
26. Psychotropic Medication Management Within Residential Treatment Centers: Physician Opinions About Difficulties and Barriers.
- Author
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Griffith, Annette, Epstein, Michael, and Huefner, Jonathan
- Subjects
- *
PSYCHIATRIC drugs , *QUESTIONNAIRES , *RESIDENTIAL care , *DATA analysis software , *PHYSICIANS' attitudes , *ADOLESCENCE - Abstract
Research has shown that between 40 and 98 % of youth entering residential treatment are taking at least one psychotropic medication and that psychotropic medication management is often an integral component of treatment in residential settings. To determine physician opinion about the difficulty of managing psychotropic medications for youth in residential treatment and to determine the resources that are used in the process, a survey study was conducted. Overall, physicians indicated that youth involved in residential settings were much more complex than those in traditional outpatient settings, due to multiple mental health diagnoses, polypharmacy, and unknown treatment histories. They also reported that many existing resources are not applicable to youth, particularly those in residential settings, and that they are difficult to read and interpret. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
27. Psychometrics and Measurement Invariance of the Emotional and Behavioral Screener.
- Author
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Lambert, Matthew C., Epstein, Michael, Ingram, Stephanie, Simpson, Amy, and Bernstein, Seth
- Subjects
- *
MENTAL status examination , *AFFECTIVE disorders , *BEHAVIOR disorders in children , *ANALYSIS of variance , *FACTOR analysis , *PSYCHOMETRICS , *SEX distribution , *STATISTICS , *DATA analysis , *CHILDREN , *DIAGNOSIS - Abstract
Many students who exhibit behavioral and emotional problems during adolescence often show less severe problems in school in early grades. Screening for these early indicators can help educational professionals direct support to students who are more likely to benefit from increased support. The screening protocol needs to be psychometrically sound, accurate in identifying students at risk, and resource efficient. The present study explored the psychometric properties of a brief behavioral screener—the 10-item Emotional and Behavioral Screener (EBS)—for a sample of 5,109 first-grade students assessed as part of a universal screening process. Confirmatory factor analysis and Rasch measurement techniques were used in conjunction to evaluate the factorial validity, item quality, rating scale functioning, and measurement invariance across gender o f the EBS. Results indicated that the EBS has largely strong psychometric properties, with a few notable exceptions: potential multidimensionality, significant differential item functioning across gender, and only moderate differentiation between rating-scale categories (i.e., response options). Limitations and directions for research to clarify some remaining questions about this screening procedure are also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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28. Revealing Individual Signatures of Human T Cell CDR3 Sequence Repertoires with Kidera Factors.
- Author
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Epstein, Michael, Barenco, Martino, Klein, Nigel, Hubank, Michael, and Callard, Robin E.
- Subjects
- *
HUMAN T cells , *COMPLEMENTARITY (Physics) , *FOOD combining , *IMMUNOLOGY , *COMPUTATIONAL biology , *IMMUNE system - Abstract
The recent development of High Throughput Sequencing technologies has enabled an individual’s TCR repertoire to be efficiently analysed at the nucleotide level. However, with unique clonotypes ranging in the tens of millions per individual, this approach gives a surfeit of information that is difficult to analyse and interpret in a biological context and gives little information about TCR structural diversity. Using publicly available TCR CDR3 sequence data, we analysed TCR repertoires by converting the encoded CDR3 amino acid sequences into Kidera Factors, a set of orthogonal physico-chemical properties that reflect protein structure. This approach enabled the TCR repertoire from different individuals to be distinguished and demonstrated the close similarity of the repertoire in different samples from the same individual. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
29. Using Direct Observation to Assist in Eligibility Decisions and Intervention Planning: The Scales for Assessing Emotional Disturbance–2 Observation Form.
- Author
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Nordness, Philip D., Epstein, Michael H., and Cullinan, Douglas
- Subjects
- *
OBSERVATION (Educational method) , *STUDENT attitudes , *STUDENTS' conduct of life , *BEHAVIORAL assessment , *CLASSROOM management ,FUNCTIONAL assessment of problem children - Abstract
The article presents the case study on the use of direct observation to aid in eligibility decisions and intervention planning to identify students with emotional disturbance (ED). The study employs Scales for Assessing Emotional Disturbance-Second Edition (SAED) observation form (OF) and functional behavioral assessment (FBA). Results reveal that through observation measures, observers can attend to classroom management that can reinforce the problem behaviors of student.
- Published
- 2013
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30. A Permutation Procedure to Correct for Confounders in Case-Control Studies, Including Tests of Rare Variation
- Author
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Epstein, Michael P., Duncan, Richard, Jiang, Yunxuan, Conneely, Karen N., Allen, Andrew S., and Satten, Glen A.
- Subjects
- *
POPULATION genetics , *HYPERGEOMETRIC distribution , *DATA analysis , *ENERGY metabolism , *PERMUTATIONS , *CASE-control method - Abstract
Many case-control tests of rare variation are implemented in statistical frameworks that make correction for confounders like population stratification difficult. Simple permutation of disease status is unacceptable for resolving this issue because the replicate data sets do not have the same confounding as the original data set. These limitations make it difficult to apply rare-variant tests to samples in which confounding most likely exists, e.g., samples collected from admixed populations. To enable the use of such rare-variant methods in structured samples, as well as to facilitate permutation tests for any situation in which case-control tests require adjustment for confounding covariates, we propose to establish the significance of a rare-variant test via a modified permutation procedure. Our procedure uses Fisher’s noncentral hypergeometric distribution to generate permuted data sets with the same structure present in the actual data set such that inference is valid in the presence of confounding factors. We use simulated sequence data based on coalescent models to show that our permutation strategy corrects for confounding due to population stratification that, if ignored, would otherwise inflate the size of a rare-variant test. We further illustrate the approach by using sequence data from the Dallas Heart Study of energy metabolism traits. Researchers can implement our permutation approach by using the R package BiasedUrn. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
31. The FMR1 Premutation and Attention-Deficit Hyperactivity Disorder (ADHD): Evidence for a Complex Inheritance.
- Author
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Hunter, Jessica, Epstein, Michael, Tinker, Stuart, Abramowitz, Ann, and Sherman, Stephanie
- Subjects
- *
ATTENTION-deficit hyperactivity disorder , *MONOGENIC & polygenic inheritance (Genetics) , *HYPERACTIVE children , *MEDICAL research , *BEHAVIOR genetics - Abstract
We recently reported elevated symptoms associated with attention-deficit hyperactivity disorder (ADHD) among adult female carriers of the FMR1 premutation. To gain insight into the contribution of this mutation in the context of polygenes, we examined the proportion of variation in these symptoms due to residual genetic factors after adjustment for the effect of the premutation. To accomplish this, we performed a familial aggregation analysis of ADHD symptoms among 231 females from 82 pedigrees using scores from the Connors Adult ADHD Rating Scales. Results indicate that after accounting for the effect of FMR1, there are significant residual polygenic effects on self-reported symptoms of ADHD, as measured by the ADHD Index ( p = 0.0117) and problems with self-concept ( p = 0.0110), one specific symptom domain associated with ADHD. For both measures, FMR1 accounts for ~5% of the variance while polygenes account for ~50% of the residual variance, suggesting that the premutation acts in concert with additional genetic loci to influence the severity of ADHD symptoms. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
32. Binaural loudness summation for speech presented via earphones and loudspeaker with and without visual cues.
- Author
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Epstein, Michael and Florentine, Mary
- Subjects
- *
LOUDSPEAKERS , *AUDIO equipment , *ECOLOGY , *HEADPHONES - Abstract
Preliminary data [M. Epstein and M. Florentine, Ear. Hear. 30, 234-237 (2009)] obtained using speech stimuli from a visually present talker heard via loudspeakers in a sound-attenuating chamber indicate little difference in loudness when listening with one or two ears (i.e., significantly reduced binaural loudness summation, BLS), which is known as 'binaural loudness constancy.' These data challenge current understanding drawn from laboratory measurements that indicate a tone presented binaurally is louder than the same tone presented monaurally. Twelve normal listeners were presented recorded spondees, monaurally and binaurally across a wide range of levels via earphones and a loudspeaker with and without visual cues. Statistical analyses of binaural-to-monaural ratios of magnitude estimates indicate that the amount of BLS is significantly less for speech presented via a loudspeaker with visual cues than for stimuli with any other combination of test parameters (i.e., speech presented via earphones or a loudspeaker without visual cues, and speech presented via earphones with visual cues). These results indicate that the loudness of a visually present talker in daily environments is little affected by switching between binaural and monaural listening. This supports the phenomenon of binaural loudness constancy and underscores the importance of ecological validity in loudness research. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
33. Objective estimation of loudness growth in hearing-impaired listeners.
- Author
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Silva, Ikaro and Epstein, Michael
- Subjects
- *
LOUDNESS , *OTOACOUSTIC emissions , *BRAIN stem , *PSYCHOACOUSTICS , *STANDARD deviations - Abstract
A methodology for the estimation of individual loudness growth functions using tone-burst otoacoustic emissions (TBOAEs) and tone-burst auditory brainstem responses (TBABRs) was proposed by Silva and Epstein [J. Acoust. Soc. Am. 127, 3629-3642 (2010)]. This work attempted to investigate the application of such technique to the more challenging cases of hearing-impaired listeners. The specific aims of this study were to (1) verify the accuracy of this technique with eight hearing-impaired listeners for 1- and 4-kHz tone-burst stimuli, (2) investigate the effect of residual noise levels from the TBABRs on the quality of the loudness growth estimation, and (3) provide a public dataset of physiological and psychoacoustical responses to a wide range of stimuli intensity. The results show that some of the physiological loudness growth estimates were within the mean-square-error range for standard psychoacoustical procedures, with closer agreement at 1 kHz. The median residual noise in the TBABRs was found to be related to the performance of the estimation, with some listeners showing strong improvements in the estimated loudness growth function when controlling for noise levels. This suggests that future studies using evoked potentials to estimate loudness growth should control for the estimated averaged residual noise levels of the TBABRs. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
34. Thermolysis of methane in a solar reactor for mass-production of hydrogen and carbon nano-materials
- Author
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Yeheskel, Jacob and Epstein, Michael
- Subjects
- *
HYDROGEN production , *METHANE , *CHEMICAL decomposition , *MASS production , *CARBON , *NANOSTRUCTURED materials , *SOLAR thermal energy , *CHEMICAL reactors - Abstract
Abstract: Solar thermolysis of methane to produce hydrogen and carbon nano-materials in a volumetric reactor/receiver with carbon particles cloud either priory seeded or chemically produced in the reactor, has been developed and tested. The reactor is based on absorbing of the concentrated solar radiation by the carbon particles and maintaining a reaction core at high temperature while the reactor walls are kept at relatively low temperatures, compatible with existing ceramic materials. The main advantage of the volumetric approach lies in its excellent heat transfer effectiveness and scalability to larger scales. As a result of computational fluid dynamics (CFD) analysis a compound reactor was designed and tested. The reactor’s most important characteristics are: high reaction temperature, transparent window protection and directional streaming flow (tornado) without boundary layer separation. Experimentally, high temperatures (up to 1500°C) in the reaction domain were achieved resulting in complete conversion of methane to hydrogen and solid carbon nano particles. Experiments were operated for periods of about 60min with steady-state temperatures and reaction products. Organometallic catalysts were mixed together with the methane feed to produce multiwalled carbon nanotubes (MWCNT). In the catalytic experiments lower temperatures were maintained which, although resulted in lower methane conversion, enhanced the MWCNT production. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
35. POTENTIAL FOR STEAM EXPLOSIONS CONSIDERING DROPLET SOLIDIFICATION AND CRUST STABILITY.
- Author
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EPSTEIN, MICHAEL, FAUSKE, HANS K., and LUANGDILOK, WISON
- Subjects
- *
THERMAL conductivity , *TRANSPORT theory , *MOLECULAR weights , *PRESSURE vessels , *ALUMINUM oxide - Abstract
It is well known that under certain circumstances a mixture of coarse, hot (molten) drops in water that forms from pouring a hot melt into water explodes. This so-called "steam explosion" is generally believed to involve fine fragmentation of the melt drops induced by steam bubble collapse and concomitant water vaporization on a timescale that is short compared with the steam pressure relief time. Motivated by a previously published idea that rapid solidification would render uranium oxide (UO2)-containing (corium) melt drops stiff and resistant to the fragmentation induced by steam bubble collapse that is requisite for an explosion, here we combine solidification theory with an available theory of the stability of thin, submerged crusts subject to acceleration to predict the "cutoff time" beyond which melt drop fragmentation is suppressed by crust cover rigidity. Illustrative calculations show that the cutoff time for corium melt drops in water is a fraction of a second and probably shorter than the time it takes to form the coarse-premixture configuration of melt drops in water that is a prerequisite for an explosion, while the opposite is true for the molten aluminum oxide (Al2O3)--water system for which the window of opportunity for an explosion is predicted to be several seconds. These theoretical findings are consistent with previous experiments that revealed molten UO2 or corium pours into water to be nonexplosive and produced steam explosions upon pouring molten Al2O3 into water. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
36. Listening Habits of iPod Users.
- Author
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Epstein, Michael, Marozeau, Jeremy, and Cleveland, Sandra
- Subjects
- *
ANALYSIS of variance , *HABIT , *MUSIC , *NOISE , *POCKET computers , *RESEARCH funding , *ENVIRONMENTAL exposure - Abstract
Purpose: To estimate real-environment iPod listening levels for listeners in 4 environments to gain insight into whether average listeners receive dosages exceeding occupational noise exposure guidelines as a result of their listening habits. Method: The earbud outputs of iPods were connected directly into the inputs of a digital recorder to make recordings of listening levels. These recordings were used to estimate listening levels using reference recordings made in a real ear. Recordings were made in 4 environments with a wide range of background noises: (a) a library, (b) a student center, (c) busy streets, and (d) the subway. Results: None of the 64 listeners were estimated to exceed allowable occupational dosages, with a maximum dose of 7.57% based on Occupational Safety and Health Administration (OSHA; 1998) methods and 10.83% based on National Institute for Occupational Safety and Health (NIOSH; 1998) methods. Conclusions: All of the listeners surveyed were exposed to dosages well below OSHA and NIOSH occupational regulations. Although this does not guarantee individual safety, the results do not support the widespread concern regarding the safety of common iPod usage. However, measurements made in this study agree with the finding that iPod output can exceed safe levels and further support recommendations to monitor and limit listening volume and listening duration. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
37. A novel power block for CSP systems
- Author
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Mittelman, Gur and Epstein, Michael
- Subjects
- *
SOLAR thermal energy , *PARABOLIC troughs , *SOLAR technology , *RANKINE cycle , *SOLAR power plants , *COST effectiveness , *COMBINED cycle power plants , *CONDENSATION - Abstract
Abstract: Concentrating Solar Thermal Power (CSP) and in particular parabolic trough, is a proven large-scale solar power technology. However, CSP cost is not yet competitive with conventional alternatives unless subsidized. Current CSP plants typically include a condensing steam cycle power block which was preferably designed for a continuous operation and higher operating conditions and therefore, limits the overall plant cost effectiveness and deployment. The drawbacks of this power block are as follows: (i) no power generation during low insolation periods (ii) expensive, large condenser (typically water cooled) due to the poor extracted steam properties (high specific volume, sub-atmospheric pressure) and (iii) high installation and operation costs. In the current study, a different power block scheme is proposed to eliminate these obstacles. This power block includes a top Rankine cycle with a back pressure steam turbine and a bottoming Kalina cycle comprising another back pressure turbine and using ammonia–water mixture as a working fluid. The bottoming (moderate temperature) cycle allows power production during low insolation periods. Because of the superior ammonia–water vapor properties, the condensing system requirements are much less demanding and the operation costs are lowered. Accordingly, air cooled condensers can be used with lower economical penalty. Another advantage is that back pressure steam turbines have a less complex design than condensing steam turbines which make their costs lower. All of these improvements could make the combined cycle unit more cost effective. This unit can be applicable in both parabolic trough and central receiver (solar tower) plants. The potential advantage of the new power block is illustrated by a detailed techno-economical analysis of two 50MW parabolic trough power plants, comparing between the standard and the novel power block. The results indicate that the proposed plant suggests a 4–11% electricity cost saving. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
38. Heritability of acoustic startle magnitude, prepulse inhibition, and startle latency in schizophrenia and control families
- Author
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Hasenkamp, Wendy, Epstein, Michael P., Green, Amanda, Wilcox, Lisette, Boshoven, William, Lewison, Barbara, and Duncan, Erica
- Subjects
- *
PEOPLE with schizophrenia , *HERITABILITY , *HABITUATION (Neuropsychology) , *STARTLE reaction , *SCHIZOPHRENIA , *GENETICS of schizophrenia , *PREVENTION - Abstract
Abstract: Prepulse inhibition (PPI) is an acoustic startle paradigm that has been used as an operational measure of sensorimotor gating. Many patients with schizophrenia have impaired PPI, and several lines of evidence suggest that PPI may represent a heritable endophenotype in this disease. We examined startle magnitude and latencies in 40 schizophrenia patients, 58 first-degree relatives of these patients, and 100 healthy controls. After removing low-startlers, we investigated PPI and startle habituation in 34 schizophrenia patients, 43 relatives, and 86 control subjects. Heritability analyses were conducted using a variance-component approach. We found significant heritability of 45% for PPI at the 60-ms interval and 67% for startle magnitude. Onset latency heritability estimates ranged between 39% and 90% across trial types, and those for peak latency ranged from 29% to 68%. Heritability of startle habituation trended toward significance at 31%. We did not detect differences between controls and either schizophrenia patients or their family members for PPI, startle magnitude, or habituation. Startle latencies were generally longer in schizophrenia patients than controls. The heritability findings give impetus to applying genetic analyses to PPI variables, and suggest that startle latency may also be a useful measure in the study of potential endophenotypes for schizophrenia. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
39. Cleaner pathways of hydrogen, carbon nano-materials and metals production via solar thermal processing
- Author
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Ozalp, Nesrin, Epstein, Michael, and Kogan, Abraham
- Subjects
- *
CLEANING compounds , *HYDROGEN , *NANOSTRUCTURED materials , *SOLAR thermal energy , *CARBON-black , *CARBON dioxide , *EMISSIONS (Air pollution) , *ECOLOGICAL impact - Abstract
Abstract: This paper describes various solar thermochemical processes for the production of hydrogen, carbon nano particles, industrial grade carbon black, and metals with substantially reduced CO2 emission footprint. The paper introduces an innovative approach of a three-dimensional volumetric production of carbon nano particles via thermal cracking of methane gained by carbon seeding as an alternative to the existing two dimensional modes. The paper also describes an alternative pathway for hydrogen production via three consecutive solar thermochemical processes, namely, solar cracking of methane, solar carbo-reduction of ZnO and CO reduction of CdO, providing long term storage of solar energy. Finally, the paper provides an example solar windowed reactor for clean production of hydrogen, and it presents numerical analysis of the solar reactor based on computational fluid dynamics results, simulating one of the major problems with natural gas cracking in solar reactors, namely, carbon contamination of the transparent window and clogging of the reactor. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
40. Estimating loudness growth from tone-burst evoked responses.
- Author
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Silva, Ikaro and Epstein, Michael
- Subjects
- *
AUDITORY evoked response , *AUDITORY perception , *BRAIN stem , *PSYCHOACOUSTICS , *PSYCHOPHYSICS - Abstract
Several studies have investigated the relationship between click-evoked auditory brainstem responses (ABRs) and loudness growth in human listeners. While some of these studies have reported promising results, showing a correlative relationship between click ABR and loudness growth as a function of level, additional studies are necessary to determine if similar results can be obtained with frequency-specific stimuli and more specific details of the loudness function can be derived from ABR recordings. The aims of this study, therefore, were to (1) develop a fully objective procedure that segments specific features of evoked, tone-burst ABR recordings, (2) investigate the feasibility of using information derived from these recordings for estimating frequency-specific loudness-growth functions, and (3) determine to what extent the loudness-growth estimation performance through ABR can be improved by controlling for residual noise levels and parametric fitting. Results from eight normal-hearing listeners using 1- and 4-kHz stimuli show that the average mean-square error of the loudness-growth estimation obtained through the procedure is comparable to that of standard psychoacoustical procedures used to estimate loudness growth. The data set has been made publicly available at www.physionet.org. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
41. Preschool Behavioral and Emotional Rating Scale (PreBERS): Test-Retest and Inter-Rater Reliability for Children with Disabilities.
- Author
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Cress, Cynthia J., Epstein, Michael H., and Synhorst, Lori
- Subjects
- *
CHILDREN with disabilities , *PRESCHOOL children , *CHILD psychology , *TEACHERS' assistants , *EMOTIONAL problems of children , *PARAPROFESSIONALS , *EDUCATION research , *STATISTICAL correlation , *BEHAVIOR disorders in children - Abstract
This article reports three studies that evaluated the test-retest and inter-rater reliability of the Preschool Behavioral and Emotional Rating Scale (PreBERS) (Epstein & Synhorst, 2009). First, teachers rated 63 children receiving school services for disability on the PreBERS, with two ratings one month apart. Second, paraprofessionals rated the same children on the PreBERS, with two ratings one month apart. Third, teacher and paraprofessional ratings were compared for inter-rater reliability between these observers. Correlations were large to very large in each of these studies, indicating that the PreBERS is a stable measure across time and raters. Recommendations for use of the PreBERS with preschool children with disabilities as well as directions for future research are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
42. Developing aftercare: Phase I: Consumer feedback
- Author
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Trout, Alexandra L. and Epstein, Michael H.
- Subjects
- *
AFTERCARE services , *CONSUMER attitudes , *TEENAGERS with disabilities , *SCHOOL failure , *COLLEGE dropouts , *PARENT attitudes , *HOME care services , *COMMUNITY schools , *HOME & school , *SOCIAL integration - Abstract
Abstract: For many adolescents with disabilities the reintegration into the home and school settings following a stay in out-of-home care is fraught with difficulties. Although many return to environments that do not facilitate school success, few services and supports are available. As a result these youth are more likely to demonstrate poor homework completion, academic failure, and dropout prior to graduation. To date, no known empirically based intervention exists to address these risks and support these youth and their families during this critical reintegration period. This article reports the findings from Phase 1 in the development of an academic-based aftercare for adolescents reintegrating into the home and community school settings following a stay in out-of-home care. Data were collected from 31 youth, parents, and school professionals through 9 structured nominal group technique focus groups to determine factors that would contribute to participant buy-in and long-term participation. Common themes identified include the desire for program flexibility, 24-hour on-call support, and well trained, supportive staff. Service and training implications, study limitations, and future research are discussed. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
43. Analysis of parameters for the estimation of loudness from tone-burst otoacoustic emissions.
- Author
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Epstein, Michael and Silva, Ikaro
- Subjects
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LOUDNESS , *OTOACOUSTIC emissions , *TONE (Phonetics) , *LISTENING , *PSYCHOACOUSTICS , *BIOACOUSTICS , *SOUND , *PHONETICS - Abstract
There is evidence that tone-burst otoacoustic emissions (TBOAEs) might be useful for estimating loudness. However, within-listener comparisons between loudness and TBOAE measurements are an essential prerequisite to determine appropriate analysis parameters for loudness estimation from TBOAE measurements. The purpose of the present work was to collect TBOAE measurements and loudness estimates across a wide range of levels in the same listeners. Therefore, TBOAEs were recorded for 1- and 4-kHz stimuli and then analyzed using a wide range of parameters to determine which parameter set yielded the lowest mean-square-error estimation of loudness with respect to a psychoacoustical, cross-modality-matching procedure and the inflected exponential (INEX) loudness model. The present results show strong agreement between 1-kHz loudness estimates derived from TBOAEs and loudness estimated using cross-modality matching (CMM), with TBOAE estimation accounting for almost 90% of the CMM variance. Additionally, the results indicate that analysis parameters may vary within a reasonable range without compromising the results (i.e., the estimates exhibit some parametric robustness). The lack of adequate parametric optimization for TBOAEs at 4 kHz suggests that measurements at this frequency are strongly contaminated by ear-canal resonances, meaning that deriving loudness estimates from TBOAEs at this frequency is significantly more challenging than at 1 kHz. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
44. Development and Standardization of a Test to Measure the Emotional and Behavioral Strengths of Preschool Children.
- Author
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Epstein, Michael H., Synhorst, Lori L., Cress, Cynthia J., and Allen, Elizabeth A.
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CHILD development , *PRESCHOOL children , *EMOTIONAL environment , *BEHAVIORAL assessment of children , *FACTOR structure , *FACTOR analysis , *READINESS for school , *CONFIDENCE in children , *CHILDREN with disabilities - Abstract
The purpose of the present study was to document the development and standardization of the Preschool Behavioral and Emotional Rating Scale and to examine its factor structure, internal consistency, and criterion validity. Data from a nationally representative sample (N = 1,471) of preschool children with and without disabilities were collected. An exploratory factor analysis identified four factors: Emotional Regulation, School Readiness, Social Confidence, and Family Involvement. The subscales and total instrument appear remarkably stable and consistent (.838 to .983). Age differences across 3-, 4-, and 5-year olds were small in magnitude, although girls were rated as possessing significantly more strengths than boys. Preschool children with disabilities were seen as having less emotional and behavioral strength than their peers without disabilities. The limitations and future research needs are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
45. Preschool Behavioral and Emotional Rating Scale (PreBERS): Test–Retest Reliability and Inter-Rater Reliability.
- Author
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Epstein, Michael and Synhorst, Lori
- Subjects
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RESEARCH on students , *PRESCHOOL children , *BEHAVIORAL assessment , *BEHAVIORAL assessment of children , *CHILD psychology , *STATISTICAL reliability - Abstract
The Preschool Behavioral and Emotional Rating Scale (PreBERS) is a standardized, norm-referenced instrument that assesses the emotional and behavioral strengths of preschool children. Two studies that investigated the test–retest and inter-rater reliability of the PreBERS are reported. In the first study, teachers rated preschool children ( N = 96) on two occasions with 1 month between ratings. Reliability coefficients for the four subscales and total score of the PreBERS were all at or above 0.86. In the second study teachers and paraprofessionals rated the same preschool children ( N = 88). All of the correlations were over 0.72. In both studies the magnitude of correlations were large indicating that the PreBERS is a stable measure across time and raters. Based on the data the PreBERS appears to be a psychometrically sound instrument appropriate for use with preschool children. Recommendations for use with preschool children as well as future research are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
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46. Probabilistic performance of state estimation across a lossy network
- Author
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Epstein, Michael, Shi, Ling, Tiwari, Abhishek, and Murray, Richard M.
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ESTIMATION theory , *PROBABILISTIC automata , *OBSERVABILITY (Control theory) , *KALMAN filtering , *ANALYSIS of covariance , *PREDICTION theory - Abstract
Abstract: We consider a discrete time state estimation problem over a packet-based network. In each discrete time step, a measurement packet is sent across a lossy network to an estimator unit consisting of a modified Kalman filter. Using the designed estimator algorithm, the importance of placing a measurement buffer at the sensor that allows transmission of the current and several previous measurements is shown. Previous pioneering work on Kalman filtering with intermittent observation losses is concerned with the asymptotic behavior of the expected value of the error covariance, i.e. as . We consider a different performance metric, namely a probabilistic statement of the error covariance , meaning that with high probability the error covariance is bounded above at any instant in time. Provided the estimator error covariance has an upper bound whenever a measurement packet arrives, we show that for any finite this statement will hold so long as the probability of receiving a measurement packet is nonzero. We also give an explicit relationship between and and provide examples to illustrate the theory. [Copyright &y& Elsevier]
- Published
- 2008
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47. A simple approach to the prediction of waterhammer transients in a pipe line with entrapped air
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Epstein, Michael
- Subjects
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PRESSURE measurement , *PARTIAL differential equations , *COMPRESSIBILITY , *PIPELINES - Abstract
Abstract: The pressure histories within entrapped air bubbles in a pipe line during a waterhammer transient are treated theoretically. A convenient integral method is introduced, which takes full account of air/water interface movement and liquid compressibility. The significance of the method is that it provides a simple equation set for approximating, with good accuracy and with a small degree of conservatism, the solution to a problem that otherwise involves coupled partial differential equations on time dependent domains with non-linear boundary conditions. The accuracy of the method is defined by its comparison with available numerical-solution-predictions and measurements of the pressure within an entrapped-air-bubble at a dead end in a pipe. The method is shown to be a computationally simple and efficient way of assessing the impact of liquid compressibility on pressure rise when multiple water columns and air pockets are present in a pipe line. [Copyright &y& Elsevier]
- Published
- 2008
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48. THERMAL STABILITY AND SAFE VENTING OF THE TRI-N-BUTYL PHOSPHATE-NITRIC ACID-WATER ("RED OIL") SYSTEM--II: EXPERIMENTAL DATA ON REACTION SELF-HEAT RATES AND GAS PRODUCTION AND THEIR CORRELATION.
- Author
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EPSTEIN, MICHAEL, FAUSKE, HANS K., ASKONAS, CHARLES F., VIAL, MARC A., and PAVIET-HARTMANN, PATRICIA
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CALORIMETRY , *ARRHENIUS equation , *NITRIC acid , *CHEMICAL reactions , *OLEIC acid , *MASS transfer - Abstract
Adiabatic calorimetry testing was performed to determine the Arrhenius relations for the chemical self-heat rates generated by the oxidation of tri-n-butyl phosphate saturated with nitric acid ("organic phase"). The adiabatic calorimetry tests showed that the runaway reaction is tempered at ~109°C when the organic phase rests on top of a layer of aqueous nitric acid ("aqueous phase"). It is believed that tempering in the laboratory-scale two-layer organic/aqueous system is mainly due to the upward transport of dissolved water from the aqueous phase to the organic phase where the water evaporates into rising reaction product gas bubbles. The rate of water transport depends strongly on the location and rate of product gas bubble generation. Isothermal tests were performed that clearly reveal that the reaction product gas bubbles originate in the underlying aqueous layer and that their rate of generation is bubbling enhanced reactant mass transfer controlled. A semiempirical expression for the rate of gas generation was developed from the measurements and from available correlations on enhanced mass transfer in bubbling pools. The empirical and semiempirical relations reported here for chemical self-heat rates and reaction product gas production are necessary to determine the thermal stability boundaries of single-layer and two-layer systems, predictions of which appear in the companion paper, "Thermal Stability and Safe Venting of the Tri-N-Butyl Phosphate-Nitric Acid-Water ("Red Oil") System--Ill: Predictions of Thermal Stability Boundaries and Required Vent Size," Nuclear Technology, Vol. 163, p. 307 (2008). [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
49. THERMAL STABILITY AND SAFE VENTING OF THE TRI-N-BUTYL PHOSPHATE-NITRIC ACID-WATER ("RED OIL") SYSTEM--I: TWO-LAYER SYSTEM MASS TRANSFER THEORY.
- Author
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EPSTEIN, MICHAEL, FAUSKE, HANS K., ASKONAS, CHARLES F., VIAL, MARC A., and PAVIET-HARTMANN, PATRICIA
- Subjects
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MASS transfer , *NITRIC acid , *NUCLEAR reactions , *HEAT transfer , *THERMODYNAMICS , *TRANSPORT theory - Abstract
Accurate prediction of the bubble-enhanced mass transport rate of dissolved water from a layer of aqueous nitric acid ("aqueous phase") to an overlying, reactive layer of tri-n-butyl phosphate and nitric acid ("organic phase") is crucial to assessing the conditions for a runaway reaction in the organic phase. This paper presents a rational, predictive model of the concentration profile history of a dissolved species in a vertical column comprising an organic phase overlying an aqueous phase. The model incorporates both interfacial and axial dispersion limitations to species transport. Open-literature correlations on enhanced heat transfer in bubbling pools, after conversion to mass transfer correlations, provide the model's needed interfacial resistance coefficients. The model shows that in laboratory-scale systems interfacial limitations to dissolved species mass transport are controlling while in full-scale columns mass transport is axial dispersion controlled. The model is capable of rationalizing available measurements of dissolved species mass transfer between the organic and aqueous phases. A previous interpretation of the measurements is shown to be incorrect. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
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50. THERMAL STABILITY AND SAFE VENTING OF THE TRI-N-BUTYL PHOSPHATE-NITRIC ACID-WATER ("RED OIL") SYSTEM--III: PREDICTIONS OF THERMAL STABILITY BOUNDARIES AND REQUIRED VENT SIZE.
- Author
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EPSTEIN, MICHAEL, FAUSKE, HANS K., ASKONAS, CHARLES F., VIAL, MARC A., and PAVIET-HARTMANN, PATRICIA
- Subjects
- *
OLEIC acid , *NITRIC acid , *CHEMICAL reactions , *CALORIMETRY , *NUCLEAR energy , *COAL gas - Abstract
A Semenov-type analysis is made of the conditions for an exothermic runaway reaction in an "organic phase" (or "red oil") made up of tri-n-butyl phosphate (TBP) saturated with nitric acid (HN03). Also, a theoretical framework is developed to predict the critical organic layer depth above which a runaway will occur when the organic layer rests on a layer of aqueous nitric acid ("aqueous phase"). Available calorimetry data on peak pressurization rates during vented TBP/HON3 reactions are rationalized using orifice flow theory, which provides a simple criterion for the required vent area for vessel pressure relief during a red oil runaway. Finally, it is shown that the Toms-7 accident can be explained by a combination of weak reaction tempering at the vessel relief valve set pressure and insufficient venting capacity. The formulations for determining the onset of a TB/ HN03 runaway outlined in this paper rely heavily on the empirical and semiempirical equations developed in the companion paper "Thermal Stability and Safe Venting of the Tri-N-Butyl Phosphate-Nitric Acid-Water ( "Red Oil") System--II: Experimental Data on Reaction Self-Heat Rates and Gas Production and Their Correlation," Nuclear Technology, Vol. 163, p. 294 (2008), which deals with the chemical self-heat rate in the organic phase, the gas production rate in the organic phase, and the superficial gas velocity across the aqueous-organic interface of a two-layer organic over acueous configuration. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
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