21 results
Changes in evening-shifted loss of control eating severity following treatment for binge-eating disorder
- Angeline R. Bottera, Elizabeth N. Dougherty, Glen Forester, Carol B. Peterson, Ross D. Crosby, Scott G. Engel, Scott J. Crow, Jennifer E. Wildes, Stephen A. Wonderlich
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- Journal:
- Psychological Medicine , First View
- Published online by Cambridge University Press:
- 28 February 2024, pp. 1-8
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Background
Loss of control eating is more likely to occur in the evening and is uniquely associated with distress. No studies have examined the effect of treatment on within-day timing of loss of control eating severity. We examined whether time of day differentially predicted loss of control eating severity at baseline (i.e. pretreatment), end-of-treatment, and 6-month follow-up for individuals with binge-eating disorder (BED), hypothesizing that loss of control eating severity would increase throughout the day pretreatment and that this pattern would be less pronounced following treatment. We explored differential treatment effects of cognitive-behavioral guided self-help (CBTgsh) and Integrative Cognitive-Affective Therapy (ICAT).
MethodsIndividuals with BED (N = 112) were randomized to receive CBTgsh or ICAT and completed a 1-week ecological momentary assessment protocol at baseline, end-of-treatment, and 6-month follow-up to assess loss of control eating severity. We used multilevel models to assess within-day slope trajectories of loss of control eating severity across assessment periods and treatment type.
ResultsWithin-day increases in loss of control eating severity were reduced at end-of-treatment and 6-month follow-up relative to baseline. Evening acceleration of loss of control eating severity was greater at 6-month follow-up relative to end-of-treatment. Within-day increases in loss of control severity did not differ between treatments at end-of-treatment; however, evening loss of control severity intensified for individuals who received CBTgsh relative to those who received ICAT at 6-month follow-up.
ConclusionsFindings suggest that treatment reduces evening-shifted loss of control eating severity, and that this effect may be more durable following ICAT relative to CBTgsh.
Prospects for a high-field, compact break-even axisymmetric mirror (BEAM) and applications
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- C.B. Forest, J.K. Anderson, D. Endrizzi, J. Egedal, S. Frank, K. Furlong, M. Ialovega, J. Kirch, R.W. Harvey, B. Lindley, Yu.V. Petrov, J. Pizzo, T. Qian, K. Sanwalka, O. Schmitz, J. Wallace, D. Yakovlev, M. Yu
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- Journal:
- Journal of Plasma Physics / Volume 90 / Issue 1 / June 2024
- Published online by Cambridge University Press:
- 17 January 2024, 975900101
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This paper explores the feasibility of a break-even-class mirror referred to as BEAM (break-even axisymmetric mirror): a neutral-beam-heated simple mirror capable of thermonuclear-grade parameters and $Q\sim 1$ conditions. Compared with earlier mirror experiments in the 1980s, BEAM would have: higher-energy neutral beams, a larger and denser plasma at higher magnetic field, both an edge and a core and capabilities to address both magnetohydrodynamic and kinetic stability of the simple mirror in higher-temperature plasmas. Axisymmetry and high-field magnets make this possible at a modest scale enabling a short development time and lower capital cost. Such a $Q\sim 1$ configuration will be useful as a fusion technology development platform, in which tritium handling, materials and blankets can be tested in a real fusion environment, and as a base for development of higher-$Q$ mirrors.
Physics basis for the Wisconsin HTS Axisymmetric Mirror (WHAM)
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- D. Endrizzi, J.K. Anderson, M. Brown, J. Egedal, B. Geiger, R.W. Harvey, M. Ialovega, J. Kirch, E. Peterson, Yu.V. Petrov, J. Pizzo, T. Qian, K. Sanwalka, O. Schmitz, J. Wallace, D. Yakovlev, M. Yu, C.B. Forest
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- Journal:
- Journal of Plasma Physics / Volume 89 / Issue 5 / October 2023
- Published online by Cambridge University Press:
- 20 September 2023, 975890501
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The Wisconsin high-temperature superconductor axisymmetric mirror experiment (WHAM) will be a high-field platform for prototyping technologies, validating interchange stabilization techniques and benchmarking numerical code performance, enabling the next step up to reactor parameters. A detailed overview of the experimental apparatus and its various subsystems is presented. WHAM will use electron cyclotron heating to ionize and build a dense target plasma for neutral beam injection of fast ions, stabilized by edge-biased sheared flow. At 25 keV injection energies, charge exchange dominates over impact ionization and limits the effectiveness of neutral beam injection fuelling. This paper outlines an iterative technique for self-consistently predicting the neutral beam driven anisotropic ion distribution and its role in the finite beta equilibrium. Beginning with recent work by Egedal et al. (Nucl. Fusion, vol. 62, no. 12, 2022, p. 126053) on the WHAM geometry, we detail how the FIDASIM code is used to model the charge exchange sources and sinks in the distribution function, and both are combined with an anisotropic magnetohydrodynamic equilibrium solver method to self-consistently reach an equilibrium. We compare this with recent results using the CQL3D code adapted for the mirror geometry, which includes the high-harmonic fast wave heating of fast ions.
Study rationale and baseline data for pilot trial of dronabinol adjunctive treatment of agitation in Alzheimer’s dementia (THC-AD)
- Leah M. Cohen, Eleanor Ash, John D. Outen, Ryan Vandrey, Halima Amjad, Marc Agronin, M. Haroon Burhanullah, Patricia Walsh, James M. Wilkins, Jeannie-Marie Leoutsakos, Milap A. Nowrangi, David Harper, Paul B. Rosenberg, Brent P. Forester
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- International Psychogeriatrics , First View
- Published online by Cambridge University Press:
- 11 October 2021, pp. 1-6
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Agitation is a common complication of Alzheimer’s dementia (Agit-AD) associated with substantial morbidity, high healthcare service utilization, and adverse emotional and physical impact on care partners. There are currently no FDA-approved pharmacological treatments for Agit-AD. We present the study design and baseline data for an ongoing multisite, three-week, double-blind, placebo-controlled, randomized clinical trial of dronabinol (synthetic tetrahydrocannabinol [THC]), titrated to a dose of 10 mg daily, in 80 participants to examine the safety and efficacy of dronabinol as an adjunctive treatment for Agit-AD. Preliminary findings for 44 participants enrolled thus far show a predominately female, white sample with advanced cognitive impairment (Mini Mental Status Examination mean 7.8) and agitation (Neuropsychiatric Inventory-Clinician Agitation subscale mean 14.1). Adjustments to study design in light of the COVID-19 pandemic are described. Findings from this study will provide guidance for the clinical utility of dronabinol for Agit-AD. ClinicalTrials.gov Identifier: NCT02792257.
Laminar and turbulent plasmoid ejection in a laboratory Parker Spiral current sheet
- Ethan E. Peterson, Douglass A. Endrizzi, Michael Clark, Jan Egedal, Kenneth Flanagan, Nuno F. Loureiro, Jason Milhone, Joseph Olson, Carl R. Sovinec, John Wallace, Cary B. Forest
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- Journal:
- Journal of Plasma Physics / Volume 87 / Issue 4 / August 2021
- Published online by Cambridge University Press:
- 05 August 2021, 905870410
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Quasi-periodic plasmoid formation at the tip of magnetic streamer structures is observed to occur in experiments on the Big Red Ball as well as in simulations of these experiments performed with the extended magnetohydrodynamics code, NIMROD. This plasmoid formation is found to occur on a characteristic time scale dependent on pressure gradients and magnetic curvature in both experiment and simulation. Single mode, or laminar, plasmoids exist when the pressure gradient is modest, but give way to turbulent plasmoid ejection when the system drive is higher, which produces plasmoids of many sizes. However, a critical pressure gradient is also observed, below which plasmoids are never formed. A simple heuristic model of this plasmoid formation process is presented and suggested to be a consequence of a dynamic loss of equilibrium in the high-$\beta$ region of the helmet streamer. This model is capable of explaining the periodicity of plasmoids observed in the experiment and simulations, and produces plasmoid periods of 90 minutes when applied to two-dimensional models of solar streamers with a height of $3R_\odot$. This is consistent with the location and frequency at which periodic plasma blobs have been observed to form by Large Angle and Spectrometric Coronograph and Sun Earth Connection Coronal and Heliospheric Investigation instruments.
Regulation of the normalized rate of driven magnetic reconnection through shocked flux pileup
- Joseph Olson, Jan Egedal, Michael Clark, Douglass A. Endrizzi, Samuel Greess, Alexander Millet-Ayala, Rachel Myers, Ethan E. Peterson, John Wallace, Cary B. Forest
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- Journal:
- Journal of Plasma Physics / Volume 87 / Issue 3 / June 2021
- Published online by Cambridge University Press:
- 29 June 2021, 175870301
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Magnetic reconnection is explored on the Terrestrial Reconnection Experiment (TREX) for asymmetric inflow conditions and in a configuration where the absolute rate of reconnection is set by an external drive. Magnetic pileup enhances the upstream magnetic field of the high-density inflow, leading to an increased upstream Alfvén speed and helping to lower the normalized reconnection rate to values expected from theoretical consideration. In addition, a shock interface between the far upstream supersonic plasma inflow and the region of magnetic flux pileup is observed, important to the overall force balance of the system, thereby demonstrating the role of shock formation for configurations including a supersonically driven inflow. Despite the specialized geometry where a strong reconnection drive is applied from only one side of the reconnection layer, previous numerical and theoretical results remain robust and are shown to accurately predict the normalized rate of reconnection for the range of system sizes considered. This experimental rate of reconnection is dependent on system size, reaching values as high as 0.8 at the smallest normalized system size applied.
Formation of transient high-β plasmas in a magnetized, weakly collisional regime
- T. Byvank, D. A. Endrizzi, C. B. Forest, S. J. Langendorf, K. J. McCollam, S. C. Hsu
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- Journal:
- Journal of Plasma Physics / Volume 87 / Issue 1 / February 2021
- Published online by Cambridge University Press:
- 20 January 2021, 905870102
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We present experimental data providing evidence for the formation of transient (${\sim }20\ \mathrm {\mu }\textrm {s}$) plasmas that are simultaneously weakly magnetized (i.e. Hall magnetization parameter $\omega \tau > 1$) and dominated by thermal pressure (i.e. ratio of thermal-to-magnetic pressure $\beta > 1$). Particle collisional mean free paths are an appreciable fraction of the overall system size. These plasmas are formed via the head-on merging of two plasmas launched by magnetized coaxial guns. The ratio $\lambda _{\textrm {gun}}=\mu _0 I_{\textrm {gun}}/\psi _{\textrm {gun}}$ of gun current $I_{\textrm {gun}}$ to applied magnetic flux $\psi _{\textrm {gun}}$ is an experimental knob for exploring the parameter space of $\beta$ and $\omega \tau$. These experiments were conducted on the Big Red Ball at the Wisconsin Plasma Physics Laboratory. The transient formation of such plasmas can potentially open up new regimes for the laboratory study of weakly collisional, magnetized, high-$\beta$ plasma physics; processes relevant to astrophysical objects and phenomena; and novel magnetized plasma targets for magneto-inertial fusion.
Long-term Treatment with Lurasidone in Older Adults with Bipolar Depression: Results of a 6 Month Open-label Study
- B. Forester, M. Sajatovic, J. Tsai, H. Kroger, A. Pikalov, J. Cucchiaro, A. Loebel
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- European Psychiatry / Volume 30 / Issue S1 / March 2015
- Published online by Cambridge University Press:
- 15 April 2020, p. 1
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Introduction
Long-term treatment of bipolar depression in the elderly has not been well-studied.
Objectives/AimsTo evaluate the long-term safety and tolerability of lurasidone in older adults (age ≥55 years) with bipolar I depression (BPD).
MethodsThe older adult sample was analyzed from an extension study in which patients who completed one of three 6 week, double-blind, placebo-controlled trials received 6 months of open-label treatment with flexible doses of lurasidone 18.5-111 mg/d, either as monotherapy, or adjunctive to lithium or valproate.
ResultsThe older adult sample consisted of 55 patients (17.4% of total) on lurasidone monotherapy and 86 patients (17.3%) on adjunctive lurasidone. At the end of 6 months of treatment with lurasidone, monotherapy and adjunctive therapy, respectively, minimal changes were observed in mean weight (-1.0 kg; -0.4 kg); and median total cholesterol (-2.0 mg/dL; +6.0 md/dL), triglycerides (+2.5 mg/dL; +6.0 mg/dL), and HbA1c (0.0%; -0.1%). The 3 most common adverse events were fatigue (18.4%), insomnia (18.4%), headache (15.8%) in the monotherapy group, and akathisia (31.7%), insomnia (22.0%), tremor (19.5%) in the adjunctive group. Discontinuation due to adverse events was low in both groups (monotherapy, 7.3%; adjunctive, 9.3%). Improvement in depression was maintained during 6 months of treatment, with a mean change in MADRS scores of -15.7 for the monotherapy group, and -17.8 for the adjunctive therapy group (from acute study baseline).
ConclusionsResults of these secondary analyses suggest that lurasidone, in doses of 18.5-111 mg/day, was a safe and well-tolerated long-term treatment for bipolar depression in older adults.
NCT00868959.
Sponsored by Sunovion Pharmaceuticals Inc.
Efficacy and Tolerability of Lurasidone in Older Adults with Bipolar Depression: Analysis of Two 6-week Double-blind, Placebo-controlled Studies
- M. Sajatovic, B. Forester, J. Tsai, H. Kroger, A. Pikalov, J. Cucchiaro, A. Loebel
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- European Psychiatry / Volume 30 / Issue S1 / March 2015
- Published online by Cambridge University Press:
- 15 April 2020, p. 1
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Introduction
The acute treatment of bipolar depression in the elderly has not been well-studied.
Objectives/AimsTo evaluate the acute efficacy and tolerability of lurasidone in older adults (age ≥55 years) with bipolar I depression (BPD).
MethodsThe older adult sample was analyzed from two, randomized, double-blind, 6-week studies of BPD patients with a Montgomery-Asberg Depression Rating Scale (MADRS) score ≥20: a monotherapy trial (lurasidone 18.5-56 mg/d vs 74-111 mg/d vs placebo); and an adjunctive trial (with lithium or valproate; lurasidone 18.5-111 mg/d vs placebo).
ResultsThe older adult sample consisted of 83 patients (17.1%) on monotherapy, and 53 patients (15.6%) on adjunctive therapy. At Week 6, mean change in MADRS was significantly greater for lurasidone 18.5-56 mg (-15.4; P<0.01; effect size=0.86) and 74-111 mg (-14.1; P<0.02; effect size=0.74) vs placebo (-7.1). Adjunctive therapy with lurasidone (vs placebo) was associated with numerically greater improvement at Week 6 in MADRS (-13.9 vs. -11.1; ns; effect size=0.26). Among older adults in the monotherapy study, discontinuation due to adverse events occurred in 7.7% of patients on lurasidone 18.5-56 mg, 6.7% on lurasidone 74-111 mg, and 3.7% on placebo; and in the adjunctive therapy study, discontinuation due to adverse events occurred in 3.8% of patients on lurasidone, and 7.4% on placebo.
ConclusionsResults of these analyses suggest that lurasidone, in doses of 18.5-111 mg, was an efficacious and well-tolerated acute treatment for bipolar depression in older adults. Significance vs placebo was achieved with lurasidone monotherapy, however, adjunctive therapy with lurasidone did not reach statistical significance.
NCT00868699, NCT00868452.
Sponsored by Sunovion Pharmaceuticals Inc.
Two new early Asteroidea (Echinodermata) and early asteroid evolution
- Daniel B. Blake, Forest J. Gahn, Thomas E. Guensburg
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- Journal of Paleontology / Volume 94 / Issue 4 / July 2020
- Published online by Cambridge University Press:
- 02 April 2020, pp. 734-747
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Aerliceaster nexosus n. gen. n. sp. (Echinodermata), one of the oldest of known asteroids, is based on six specimens from the Floian (Early Ordovician) Garden City Formation of Idaho, and Kolataster perplexus n. gen. n. sp. is based on two specimens from the Sandian (Late Ordovician) Mifflin Formation of Illinois. Although the asterozoan skeleton is subdivided into few ossicular categories, evolutionary derivations of all the categories are not fully established, and therefore published evaluations differ. Beginning with phylogenetic work placing asteroid ancestry within the Somasteroidea together with the new taxa described herein, aspects of early asteroid morphology are evaluated and ambiguities in need of further study identified. Uncertainties are considered to be founded in rapid early asterozoan diversification and the scanty fossil record.
UUID: http://zoobank.org/b43d07cc-c8fb-4a84-bc6f-40aa6e0daea2
An Early Ordovician (Floian) asterozoan (Echinodermata) of problematic class-level affinities
- Daniel B. Blake, Forest J. Gahn, Thomas E. Guensburg
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- Journal of Paleontology / Volume 94 / Issue 2 / March 2020
- Published online by Cambridge University Press:
- 28 October 2019, pp. 358-365
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Falloaster anquiroisitus new genus new species (Asterozoa, Echinodermata) is described from the Floian (Early Ordovician) Garden City Formation of Idaho. The new taxon is known from a single small specimen. Because of weathering, remaining disk elements are incomplete. Dorsal surfaces of the ambulacral ossicles of two arms are available, one well preserved, whereas those of a third arm expose the ambulacrals essentially as they would appear in ventral view. Ambulacral ossicles were all but entirely lost on the remaining two arms.
Albeit asterozoan, F. anquiroisitus is not assignable at the class level. It is suggestive of the Asteroidea in presence of a domal disk, five abruptly tapering triangular, arched arms, and ambulacral ossicles vaulted to form a furrow. Ambulacral morphology, including the presence of very large podial pores, is unlike that of early asteroids. In addition, no adambulacral or other virgal-series derivatives are present; ambital framework ossicles are absent; a single series of enlarged, plate-like arm ossicles, one series on each side of the arm, come together at the arm midline; and the plate-like series were supported laterally by recurved ambulacral margins. Only remnants of the disk near the periphery survive, these of overall expression unlike any other echinoderm, including asterozoans. The mouth frame is unknown. Falloaster anquiroisitus is argued to represent an extinct lineage apart from the four recognized asterozoan classes, thereby joining a limited number of other problematic early Asterozoa.
UUID: http://zoobank.org/a13a5417-44b6-4ac3-90cf-9dc8fb5902bd
High ionisation fraction plasmas in a low temperature, multidipole cusp plasma
- V. Désangles, J. Milhone, C. Cooper, D. B. Weisberg, M. D. Nornberg, C. B. Forest
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- Journal of Plasma Physics / Volume 84 / Issue 3 / June 2018
- Published online by Cambridge University Press:
- 19 June 2018, 905840312
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The depletion of neutral helium atoms has been studied in an unmagnetised spherical plasma created by DC discharge in a multidipole confinement field. Knowing the neutral density profile is critical to predicting the equilibrium flow of such plasmas. A model of the emissivity due to electron-impact excitation of neutral atoms in the plasma has been derived and used to fit radiance measurements of several neutral transitions to extract the radial profile of neutral density for plasmas of varying temperature and density. We report a depletion of the core neutral density varying between negligible levels to 80 % of the edge neutral density depending on the input power and fuelling. The corresponding ionisation fraction varies between 30–80 % in the plasma core. A simple neutral diffusion model is sufficient to describe the shape of neutral density profile implied by the radiance measurements. We have used the measurements to include a drag force due to neutral charge-exchange collisions in simulations of driven plasma flow. The simulation predicts a better fit to Mach probe flow measurements when this neutral drag is accounted for. This work shows that accounting for a realistic neutral profile is important to predict the plasma flow geometry and its magnetohydrodynamics (MHD) stability.
Driving magnetic turbulence using flux ropes in a moderate guide field linear system
- Matthew I. Brookhart, Aaron Stemo, Roger Waleffe, Cary B. Forest
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- Journal of Plasma Physics / Volume 83 / Issue 6 / December 2017
- Published online by Cambridge University Press:
- 09 November 2017, 905830604
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We present a series of experiments on novel, line-tied plasma geometries as a study of the generation of chaos and turbulence in line-tied systems. Plasma production and the injection scale for magnetic energy is provided by spatially discrete plasma guns that inject both plasma and current. The guns represent a technique for controlling the injection scale of magnetic energy. A two-dimensional (2-D) array of magnetic probes provides spatially resolved time histories of the magnetic fluctuations at a single cross-section of the experimental cylinder, allowing simultaneous spatial measurements of chaotic and turbulent behaviour. The first experiment shows chaotic fluctuations and self-organization in a hollow-current line-tied screw pinch. These dynamics is modulated primarily by the applied magnetic field and weakly by the plasma current and safety factor. The second experiment analyses the interactions of multiple line-tied flux ropes. The flux ropes all exhibit chaotic behaviour, and under certain conditions develop an inverse cascade to larger scales and a turbulent inertial range with magnetic energy ($E$) related to perpendicular wave number ($k_{\bot }$) as $E\propto k_{\bot }^{-2.5\pm 0.5}$.
The Wisconsin Plasma Astrophysics Laboratory
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- C. B. Forest, K. Flanagan, M. Brookhart, M. Clark, C. M. Cooper, V. Désangles, J. Egedal, D. Endrizzi, I. V. Khalzov, H. Li, M. Miesch, J. Milhone, M. Nornberg, J. Olson, E. Peterson, F. Roesler, A. Schekochihin, O. Schmitz, R. Siller, A. Spitkovsky, A. Stemo, J. Wallace, D. Weisberg, E. Zweibel
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- Journal:
- Journal of Plasma Physics / Volume 81 / Issue 5 / October 2015
- Published online by Cambridge University Press:
- 07 August 2015, 345810501
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The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a $10~\text{m}^{3}$, fully ionized, magnetic-field-free plasma in a spherical geometry. Plasma parameters of $T_{e}\approx 5$ to $20~\text{eV}$ and $n_{e}\approx 10^{11}$ to $5\times 10^{12}~\text{cm}^{-3}$ provide an ideal testbed for a range of astrophysical experiments, including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds and more. This article describes the capabilities of WiPAL, along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
Prospects for observing the magnetorotational instability in the plasma Couette experiment
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- K. Flanagan, M. Clark, C. Collins, C. M. Cooper, I. V. Khalzov, J. Wallace, C. B. Forest
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- Journal:
- Journal of Plasma Physics / Volume 81 / Issue 4 / August 2015
- Published online by Cambridge University Press:
- 06 May 2015, 345810401
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Many astrophysical disks, such as protoplanetary disks, are in a regime where non-ideal, plasma-specific magnetohydrodynamic (MHD) effects can significantly influence the behaviour of the magnetorotational instability (MRI). The possibility of studying these effects in the plasma Couette experiment (PCX) is discussed. An incompressible, dissipative global stability analysis is developed to include plasma-specific two-fluid effects and neutral collisions, which are inherently absent in analyses of Taylor–Couette flows (TCFs) in liquid metal experiments. It is shown that with boundary driven flows, a ion-neutral collision drag body force significantly affects the azimuthal velocity profile, thus limiting the flows to regime where the MRI is not present. Electrically driven flow (EDF) is proposed as an alternative body force flow drive in which the MRI can destabilize at more easily achievable plasma parameters. Scenarios for reaching MRI relevant parameter space and necessary hardware upgrades are described.
The wall-pressure spectrum of high-Reynolds-number turbulent boundary-layer flows over rough surfaces
- Timothy Meyers, Jonathan B. Forest, William J. Devenport
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- Journal:
- Journal of Fluid Mechanics / Volume 768 / 10 April 2015
- Published online by Cambridge University Press:
- 09 March 2015, pp. 261-293
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Experiments have been performed on a series of high-Reynolds-number flat-plate turbulent boundary layers formed over rough and smooth walls. The boundary layers were fully rough, yet the elements remained a very small fraction $({<}1.4\,\%)$ of the boundary-layer thickness, ensuring conditions free of transitional effects. The wall-pressure spectrum and its scaling were studied in detail. One of the major findings is that the rough-wall turbulent pressure spectrum at vehicle relevant conditions is comprised of three scaling regions. These include a newly discovered high-frequency region where the pressure spectrum has a viscous scaling controlled by the friction velocity, adjusted to exclude the pressure drag on the roughness elements.
Pressure fluctuations produced by forward steps immersed in a turbulent boundary layer
- Manuj Awasthi, William J. Devenport, Stewart A. L. Glegg, Jonathan B. Forest
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- Journal:
- Journal of Fluid Mechanics / Volume 756 / 10 October 2014
- Published online by Cambridge University Press:
- 02 September 2014, pp. 384-421
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Experiments have been performed on the disturbance of a high-Reynolds-number turbulent boundary layer by three forward steps with sizes close to 3.8, 15 and 60 % of the boundary layer thickness. Particular attention is focused on the impact of the steps on the fluctuating surface pressure field. Measurements were made from 5 boundary layer thicknesses upstream to 22 boundary layer thicknesses downstream of the step, a distance equivalent to over 600 step heights for the smallest step size. Flow speeds of 30 and $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}60\ \mathrm{m}\ {\mathrm{s}}^{-1}$ were studied, corresponding to boundary layer momentum thickness Reynolds numbers of 15 500 and 26 600 and step size Reynolds numbers from 6640 to 213 000. The steps produce a disturbance to the boundary layer pressure spectrum that scales on step size and decays remarkably slowly with distance downstream. When normalized on step height and free-stream velocity, the disturbance is self-similar and appears to develop almost independently of the enveloping boundary layer. The disturbance is still clearly visible at 150 step heights downstream of the mid-size step. Pressure correlations show the disturbance to be characterized by organized quasiperiodic motions that become visible well downstream of reattachment. The coherence and scale of these motions, as seen in the wall pressure correlations, scales on the step height and thus their visibility relative to the boundary layer grows rapidly as the step size is increased.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. 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Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. 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Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
- Print publication:
- 20 September 2010, pp xi-xliv
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Ostracodes as Hydrologic Indicators in Springs, Streams and Wetlands: A Tool for Environmental and Paleoenvironmental Assessment
- Alison J. Smith, Jesse W. Davis, Donald F. Palmer, Richard M. Forester, B. Brandon Curry
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- Journal:
- The Paleontological Society Papers / Volume 9 / November 2003
- Published online by Cambridge University Press:
- 21 July 2017, pp. 203-222
- Print publication:
- November 2003
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Although the majority of publications on extant nonmarine ostracode species in North America are concerned with lacustrine settings, many species that are potentially valuable as indicators of water quality changes live in non-lacustrine settings. Ostracode distributions in 157 springs, wetlands and streams in the United States are examined here in order to assess 1) species richness, 2) association with physical and chemical parameters of their habitats and 3) the presence of potentially useful biomonitors and environmental sentinels. The 157 non-lacustrine sites are a subset of a large database (North American Non-marine Ostracode Database: NANODe version 1) consisting of 611 mostly lacustrine sites with ostracode species, presence-absence data, hydrochemistry and climate data (Forester et al., in review). Of the 89 species represented in NANODe version 1, 51 species are found in springs, 59 species are found in wetlands and only 15 species are found in streams. Many species are found in at least two of these habitats and some in all three. Principal Components Analysis of these 157 sites indicates that 71% of the variance is explained by salinity (total ionic concentration), alkalinity and temperature, a result consistent with previously published analyses of natural water. Cluster analysis shows that spring species are most strongly tied to temperature, whereas wetlands and streams are most strongly tied to ionic composition. Three species are found to be potentially valuable biomonitors: Cavernocypris wardi in springs, Fabaeformiscandona rawsoni in wetlands and Physocypria globula in streams.
Diagnostic depressive symptoms of the mixed bipolar episode
- F. CASSIDY, E. AHEARN, E. MURRY, K. FOREST, B. J. CARROLL
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- Journal:
- Psychological Medicine / Volume 30 / Issue 2 / March 2000
- Published online by Cambridge University Press:
- 01 March 2000, pp. 403-411
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Background. There is not yet consensus on the best diagnostic definition of mixed bipolar episodes. Many have suggested the DSM-III-R/-IV definition is too rigid. We propose alternative criteria using data from a large patient cohort.
Methods. We evaluated 237 manic in-patients using DSM-III-R criteria and the Scale for Manic States (SMS). A bimodally distributed factor of dysphoric mood has been reported from the SMS data. We used both the factor and the DSM-III-R classifications to identify candidate depressive symptoms and then developed three candidate depressive symptom sets. Using ROC analysis we determined the optimal threshold number of symptoms in each set and compared the three ROC solutions. The optimal solution was tested against the DSM-III-R classification for cross-validation.
Results. The optimal ROC solution was a set, derived from both the DSM-III-R and the SMS, and the optimal threshold for diagnosis was two or more symptoms. Applying this set iteratively to the DSM-III-R classification produced the identical ROC solution. The prevalence of mixed episodes in the cohort was 13·9% by DSM-III-R, 20·2% by the dysphoria factor and 27·4% by the new ROC solution.
Conclusions. A diagnostic set of six dysphoric symptoms (depressed mood, anhedonia, guilt, suicide, fatigue and anxiety), with a threshold of two symptoms, is proposed for a mixed episode. This new definition has a foundation in clinical data, in the proved diagnostic performance of the qualifying symptoms, and in ROC validation against two previous definitions that each have face validity.