Although reliever-triggered inhaled glucocorticoid therapy can reduce asthma exacerbations, this approach has not been well studied in Black and Latinx populations, who bear disproportionate asthma ...morbidity and mortality. In a pragmatic trial involving Black and Latinx patients, the asthma exacerbation rate was lower with reliever-triggered inhaled glucocorticoid use than with usual care.
Terrestrial ecosystems contribute significant amounts of dissolved organic carbon (DOC) to aquatic ecosystems. Temperate lakes vary in DOC concentration as a result of variation in the spatial ...configuration and composition of vegetation within the watershed, hydrology, and within-lake processes. We have developed and parameterized a spatially explicit model of lake DOC concentrations, using data from 428 watersheds in the Adirondack Park of New York. Our analysis estimates watershed loading to each lake as a function of the cover type of each 10 x 10 m grid cell within the watershed, and its flow-path distance to the lake. The estimated export rates for the three main forest cover types were$37.7-47.0 kg C\cdot ha^{-1}\cdot yr^{-1}$. The four main wetland cover types had much higher rates of export per unit area ($188.4-227.0 kg C\cdot ha^{-1}\cdot yr^{-1}$), but wetlands occupied only 11%, on average, of watershed area. As a result, upland forests were the source of ~70% of DOC loading. There was evidence of significant interannual variation in DOC loading, correlated with interannual variation in precipitation. Estimated net in situ DOC production within the lakes was extremely low ($<1 kg C\cdot ha^{-1}\cdot yr^{-1}$). Many of the lakes have large watersheds relative to lake volume and have correspondingly high flushing rates. As a result, losses due to lake discharge generally had a larger effect on lake DOC concentrations than in-lake decay. Our approach can be readily incorporated within a GIS framework and allows examination of scenarios such as loss of wetlands, alterations in forest management, or increases in conserved areas, as a function of the unique configuration of individual watersheds.
The time-dependent radial and poloidal velocity of edge turbulence is evaluated using a 2D time-delayed cross-correlation analysis of fast camera data from the gas puff imaging (GPI) diagnostic ...viewing the outer midplane region in Alcator C-Mod. The local poloidal velocity fluctuations are averaged over the poloidal viewing region of the GPI diagnostic and radially resolved over ±2 cm around the separatrix. The resulting poloidal velocity usually has a broadband frequency spectrum in the range ∼1-20 kHz, and a radial correlation width which decreases with increasing line-averaged density. In some cases with ICRH heating there was also a coherent poloidal velocity oscillation at 6-7 kHz which was highly correlated with a poloidal magnetic field oscillation at the same frequency. Some of these results are similar to the geodesic acoustic modes and/or zonal flows described in previous experiments and theory.
Visible imaging has been used to provide the 2D spatial structure and temporal evolution of the profile of high-energy neutrals introduced by neutral beam injection, the fast ion profile and a ...variety of plasma instabilities in DIII-D plasmas; the combination of these techniques form a comprehensive fast ion physics diagnostic suite. The injected neutral profile is imaged in Doppler shifted
D
α
light induced by collisional excitation. Fast ion profile information was obtained through imaging of Doppler shifted fast ion
D
α
light (FIDA) emitted by re-neutralized energetic ions. Imaging of FIDA emission during sawtooth events shows a large central depletion following sawtooth crashes—indicative of a broad redistribution of fast ions. Two examples of instability structure measurements are given. Measurements of the detailed 2D poloidal structure of rotating tearing modes were obtained using spectrally filtered fast imaging of broadband visible bremsstrahlung emission, a method which is capable of imaging with high resolution the structure of coherent oscillations in the core of current and next-step fusion plasma experiments and can be applied to virtually any mode with a finite perturbed bremsstrahlung emissivity and frequency in the laboratory frame. Measurements are also presented of the
n
= 0 energetic particle geodesic acoustic mode which were made by observing fluctuations in active emission.
LaryngoPharyngeal Reflux (LPR) is characterized by symptoms, signs, and/or tissue damage
resulting from the aggression of the gastrointestinal contents in the upper airways. The Reflux Finding
Score ...(RFS) assesses the laryngeal signs through laryngoscopy. The Reflux Symptom Index (RSI) scores
the LPR symptoms. The objective of this real-world study was to compare RFS with RSI in a cohort of
Italian LPR patients. Globally, 3932 patients with LPR were evaluated and RFS and RSI were assessed in
all subjects. A moderate correlation was found between RSI and RFS (r=0.484, p<0.0001). In conclusion,
the RSI and RFS can easily be included in the LPR work-up as objective and consistent parameters,
with low cost and high practicality. Based on these clinical outcomes, the specialist can easily use these
tests in clinical practice.
Cytomegalovirus retinitis is the most common opportunistic infection of the eye in patients with the acquired immunodeficiency syndrome (AIDS).
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If untreated, cytomegalovirus retinitis is ...invariably progressive, leading to retinal necrosis and loss of vision.
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Three antiviral drugs — ganciclovir, foscarnet, and cidofovir — are approved for the treatment of cytomegalovirus retinitis. Although these drugs are initially effective in delaying the progression of cytomegalovirus retinitis,
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relapse during intravenous maintenance therapy is common,
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and such a finding is thought to be inevitable with sufficient follow-up.
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Concern about limited efficacy, the toxicity of each drug,
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Magnetohydrodynamic (MHD) instabilities in tokamak plasmas manifest in a variety of ways, characterized by different scale lengths and mode frequencies. MHD activity can cause significant degradation ...of plasma performance due to transport of particles, energy and current. Among the many different types of MHD, arguably fishbones, sawteeth and Alfvén eigenmodes (AEs) are observed to cause the largest fluxes of superthermal ions. DIII-D's expansive suite of diagnostics makes it possible to rigorously characterize these instabilities and study their interaction with fast ions. This review paper first presents an overview of the recent additions to DIII-D's collection of fast-ion diagnostics. The extended diagnostic capabilities are employed in a series of experiments to investigate fast-ion dynamics in the presence of fishbones, sawteeth and AEs. Results from these seemingly unrelated studies are highlighted, and they reveal that mode-particle resonances play the central role in the observed deterioration of fast-ion confinement.
Evidence has accumulated suggesting that HIV-infected patients are under chronic oxidative stress. Perturbations to the antioxidant defense system, including changes in levels of ascorbic acid, ...tocopherols, carotenoids, selenium, superoxide dismutase, and glutathione, have been observed in various tissues of these patients. Elevated serum levels of hydroperoxides and malondialdehyde also have been noted and are indicative of oxidative stress during HIV infection. Indications of oxidative stress are observed in asymptomatic HIV-infected patients early in the course of the disease. Oxidative stress may contribute to several aspects of HIV disease pathogenesis, including viral replication, inflammatory response, decreased immune cell proliferation, loss of immune function, apoptosis, chronic weight loss, and increased sensitivity to drug toxicities. Glutathione may play a role in these processes, and thus, agents that replete glutathione may offer a promising treatment for HIV-infected patients. Clinical studies are underway to evaluate the efficacy of the glutathione-repleting agents, L-2-oxothiazolidine-4-carboxylic acid (OTC) and
N-acetylcysteine (NAC), in HIV-infected patients.
A general criterion is proposed and found to successfully predict the emergence of chirping oscillations of unstable Alfvénic eigenmodes in tokamak plasma experiments. The model includes realistic ...eigenfunction structure, detailed phase-space dependences of the instability drive, stochastic scattering and the Coulomb drag. The stochastic scattering combines the effects of collisional pitch angle scattering and micro-turbulence spatial diffusion. The latter mechanism is essential to accurately identify the transition between the fixed-frequency mode behavior and rapid chirping in tokamaks and to resolve the disparity with respect to chirping observation in spherical and conventional tokamaks.
Experiments in the DIII-D tokamak show that many overlapping small-amplitude Alfvén eigenmodes (AEs) cause fast-ion transport to sharply increase above a critical threshold in beam power, leading to ...fast-ion density profile resilience and reduced fusion performance. The threshold is above the AE linear stability limit and varies between diagnostics that are sensitive to different parts of fast-ion phase-space. Comparison with theoretical analysis using the nova and orbit codes shows that, for the neutral particle diagnostic, the threshold corresponds to the onset of stochastic particle orbits due to wave-particle resonances with AEs in the measured region of phase space. The bulk fast-ion distribution and instability behavior was manipulated through variations in beam deposition geometry, and no significant differences in the onset threshold outside of measurement uncertainties were found, in agreement with the theoretical stochastic threshold analysis. Simulations using the 'kick model' produce beam ion density gradients consistent with the empirically measured radial critical gradient and highlight the importance of including the energy and pitch dependence of the fast-ion distribution function in critical gradient models. The addition of electron cyclotron heating changes the types of AEs present in the experiment, comparatively increasing the measured fast-ion density and radial gradient. These studies provide the basis for understanding how to avoid AE transport that can undesirably redistribute current and cause fast-ion losses, and the measurements are being used to validate AE-induced transport models that use the critical gradient paradigm, giving greater confidence when applied to ITER.
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