A5005171664- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Receptor Mechanisms and Signaling
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Plasma Diagnostics and Applications
- Neuropeptides and Animal Physiology
- Laser-Plasma Interactions and Diagnostics
- Superconducting Materials and Applications
- Neuroscience and Neuropharmacology Research
- Stress Responses and Cortisol
- Laser-induced spectroscopy and plasma
- Digital Holography and Microscopy
- Pharmacological Receptor Mechanisms and Effects
- Nuclear Physics and Applications
- Neurotransmitter Receptor Influence on Behavior
- Growth Hormone and Insulin-like Growth Factors
- Protein Kinase Regulation and GTPase Signaling
- Estrogen and related hormone effects
- Ion channel regulation and function
- Hormonal Regulation and Hypertension
- Semiconductor materials and devices
- Neuroendocrine regulation and behavior
- Laser Design and Applications
- Solar and Space Plasma Dynamics
Oak Ridge Associated Universities
2024
Third Dimension Technologies (United States)
2007-2021
Uniformed Services University of the Health Sciences
1992-2021
Oak Ridge National Laboratory
1989-2013
Khon Kaen University
2007
Fusion Academy
1983-1995
Georgia Institute of Technology
1986-1992
Princeton University
1984-1987
National Institutes of Health
1978-1986
Health and Human Development (2HD) Research Network
1984-1986
The transport effects induced by resistive ballooning modes are estimated from a theory, and found to be mainly thermal electron conduction losses. An expression for diffusivity ${\ensuremath{\chi}}_{e}$ is derived. theoretical predictions agree well with experimental values of obtained power balance the ISX-$B$ plasmas at high poloidal beta.
The dopamine receptor in the intermediate lobe (IL) of hypophysis rat is characterized on basis ability and other dopaminergic agonists to decrease consequences activation β-adrenoceptor. Stimulation diminishes L-isoproterenol- induced accumulation cAMP catecholaminestimulated enhancement adenylate cyclase activity. IL can be assigned category designated D-2 following criteria: 1) occupancy does not result activity or an cAMP, 2) ergots apomorphine mimic inhibitory effect upon formation αMSH...
The D-2 dopamine receptor mediates inhibition of adenylate cyclase in rat intermediate lobe; this is linked to by the inhibitory guanyl nucleotide-binding protein (Ni).The functioning components system was compared control and pertussis toxin-treated tissues.(-)-N-n-Propylnorapomorphine ((-)-NPA), a agonist, 5'-guanylyl imidodiphosphate (Gpp(NH)p), nonhydrolyzable GTP analog, caused dose-dependent tissue.Pertussis toxin abolished receptor-mediated but did not alter Gpp(NH)p-induced...
Recent calculations have shown that when external momentum sources and plasma rotation are included in the neoclassical theory, standard results for impurity transport can be strongly altered. Under appropriate conditions, inward convection is reduced by co-injection enhanced counter-injection. In order to examine theoretical predictions, several observations of been made ISX-B tokamak during neutral-beam injection comparison with seen Ohmic heating alone. Both intrinsic contaminants...
In experiments using a cell-free homogenate of the intermediate lobe hypophysis rat, apomorphine, dopaminergic agonist, diminished both basal and L-isoproterenol-stimulated adenylate cyclase activity; antagonists from several chemical families reversed these inhibitory effects apomorphine. Apomorphine ability GTP to enhance activity but did not directly interfere with interaction between beta-adrenoceptor L-isoproterenol. The affinity D-2 dopamine receptor in for each antagonist used this...
Thyrotropin-releasing hormone (TRH) stimulated a rapid rise in inositol trisphosphate (IPS) formation and prolactin release from 7315c tumor cells.The potencies (half-maximal) of TRH stimulating IPS were 100 f 30 140 nM, respectively.Pretreatment the cells with pertussis toxin (for up to 24 h) had no effect on either process.Pretreatment cholera (30 I1M for also failed affect basal or TRHstimulated formation.TRH was able stimulate half-maximal potency 118 10 n M lysed cell preparation cells;...
Confinement studies on the Impurity Study Experiment (ISX-B) in beam-heated plasmas contaminated with small quantities of low-Z impurities are reported. Experimental results correlation particle and energy confinement presented. A linear relationship plasma density is observed. As increased further, this effect saturates becomes independent electron density. The experiments have been extended to higher beam power, resulting an expansion ISX-B operating space. Impurities other than neon...
After treatment with cholera toxin, homogenates of intact intermediate lobe (IL) tissue rat pituitary gland synthesized more cAMP than did untreated IL tissue, and only in the presence GTP dopamine or apomorphine diminish elevated adenylate cyclase activity toxin-treated tissue. Furthermore, when tested on 5'-guanylyl imidodiphosphate [Gpp(NH)p] two other nonhydrolyzable analogs inhibited absence either a dopaminergic agonist GTP; reversed Gpp(NH)p-induced inhibition activity. Apomorphine,...
Plasma fuelling with pellet injection, pacing of edge localized modes (ELMs) by small frequent pellets and disruption mitigation gas jets or injected solid material are some the most important technological capabilities needed for successful operation ITER. Tools being developed at Oak Ridge National Laboratory that can be employed on ITER to provide necessary core ELMs disruptions. Here we present progress development technology reliable high throughput inner wall fuelling, ELM frequency...
The β-adrenoceptor in the intermediate lobe (IL) of hypophysis rat is characterized on basis following: 1) ability β-adrenergic agonists to increase adenylate cyclase activity homogenates IL, and 2) drugs active upon compete with [l2I]hydroxybenzylpindolol, a radiolabeled antagonist, for high affinity (Kd = 232 pin) binding sites. values obtained either assay system are good agreement. relative potency among agonists,lisoproterenol > lepinephrine lnorepinephrine, suggests that receptor β-2...
High-speed pellet fuelling experiments have been performed on the ISX-B device in a new regime characterized by large global density rise both Ohmically and neutral-beam heated discharges. Hydrogen pellets of 1 mm diameter were injected plasma midplane at velocities exceeding km·s−1. In low-temperature Ohmic discharges, penetrate beyond magnetic axis, such cases sharp decrease ablation is observed as passes centre. This behaviour can be accounted for an model that includes dynamic cooling...
Neutral-beam injection of up to 2.5 MW into plasmas in the ISX-B tokamak (R0 = 0.93 m, a 0.27 BT 0.9–1.5 T, Ip 70–210 kA, e 2.5–10×1013 cm−3) has created with volume-averaged beta ∼ 2.5%, peak values 9%, and root-mean-square 3.5%. Energy confinement time is observed decrease by about factor two as beam power goes from 0 MW; caused predominantly electron falling below predictions 'Alcator scaling' 3–4 at high power. An empirical relationship form fits our measurements over wide range plasma...
Abstract Repeated daily cocaine injections have been shown to alter μ‐opioid receptor densities in the caudate putamen and nucleus accumbens of rat brain (Unterwald et al., 1991, 1992). Addenylyl cyclase activity was measured rostral following repeated administration determine functional consequences cocaine‐induced opioid changes. Male Fischer rats were injected for 14 days with saline or HC1 (30 45 mg/kg/day, i.p.) three equal doses at 1‐hr intervals. Basal adenylyl effects selective μ‐...
The TFTR tokamak has reached its original machine design specifications (Ip=2.5 MA and BT=5.2 T). Recently, the D degrees neutral beam heating power been increased to 6.3 MW. By operating at low plasma current (Ip approximately=0.8 MA) density (ne approximately=1*1019 m-3), high ion temperatures (9+or-2 keV) rotation speeds (7*105 m/s) have achieved during injection. At opposite extreme, pellet injection into plasmas used increase line-average 8*1019 m-3 central 1.6*1020 m-3. This wide range...
Stimulation of the D-2 dopamine receptor inhibits pro-opiomelanocortin (POMC) synthesis in isolated rat intermediate lobe tissue. Intermediate tissue was incubated absence or presence various dopaminergic compounds, and then its capacity to incorporate [3H]tyrosine into POMC tested. agonists caused a dose-dependent inhibition synthesis; maximal inhibitory effect approximately 50% reduction amount synthesized. antagonists blocked each agonist. Pretreatment with pertussis toxin abolished...
The ability of several chemically modified forms glucagon to activate adenylate cyclase have been compared with their displace 125I-glucagon from specific membrane binding sites. results demonstrate that both NH2-terminal and COOH-terminal portions the peptide, as well central region molecule, are all involved in receptor subsequent activation cyclase. Receptor was very sensitive chemical modification polar residues glucagon. For example, conversion sole lysine residue homoarginine resulted...
Treatment of rats with 2-Br-alpha-ergocryptine (bromocriptine; CB 154) elicits biochemical, physiological, and histological changes in the intermediate lobe (IL) rat pituitary gland, suggesting a decrease activity IL. 154 treatment decreases 1) capacity IL to synthesize proopiomelanocortin (POMC), 2) content mRNA directing synthesis POMC, 3) peptides desacetyl alpha MSH, N,O-diacetyl MSH. also causes 40% loss protein an atrophy has biphasic effect upon MSH-like peptides; drug first increases...
Adrenal cAMP and plasma corticosterone levels were determined in pre-weanling rats subjected to treatment with either ACTH (50 mU/rat) or histamine dihydrochloride (0.2 mg/g body wt). injection elevated both serum adrenal on all days tested. However, the ACTH-induced elevation of diminished steadily from day 2 8 then increased 16. Histamine resulted a pattern similar that response ACTH. did not result any significant increase 10. From 12 16 concentration rose parallel ther levels. These...
Abstract: Antibodies directed against the C‐terminal and N‐terminal regions of μ‐opioid receptor were generated to identify G proteins that coimmunoprecipitate with μ receptor. Two fusion constructed: One contained 50 amino acids receptor, other 61 near N terminus Antisera both capable immunoprecipitating ∼70% solubilized rat brain receptors as determined by [ 3 H][D‐Ala 2 , ‐Me‐Phe 4 ,Gly‐ol 5 ]‐enkephalin ([ H]DAMGO) saturation binding. The material immunoprecipitated antisera was...
The effects of varying the sodium concentration (at constant ionic strength) on opioid binding at mu- and delta-opioid receptors in 7315c NG108-15 cells has been examined. [3H]etorphine to mu-receptors was increased by replacing incubation medium with potassium or N-methyl-D-glucamine. This effect shown be attributable an increase affinity, no change maximum number sites, both cell membrane suspensions intact cells. Replacement N-methyl-D-glucamine also resulted binding, but these associated...
[3H]Spiroperidol ([3H]SPIRO) binds with high affinity (Kd = 0.3 nM) to cell-free homogenates of the neurointermediate lobe rat pituitary gland. The contains 19.2 fmol specific binding sites, 86% which occur in intermediate (IL). Compounds active upon D-2 dopamine receptor IL compete [3H] SPIRO for occupancy site. Guanosine 5′- triphosphate decreases agonists, but not antagonists, For each drug tested, methods derived from competitive enzyme kinetics were used calculate apparent constants...
The 7315c cell, derived from a rat anterior pituitary tumor, expresses an angiotensin II (AII) receptor. [3H]AII binds to membranes specifically and saturably (Kd = 2.1 +/- 0.6 x 10(-6) M, Bmax 282 33 fmol/mg of protein). GTP diminished the affinity for 4.1 0.4 10(-9) 210 26 binding was displaced by AII (Ki 1.3 M), III (AIII) 0.9 nonpeptide antagonist DuP753 1.4 10(-8) M). In contrast, second ligand, PD123177, did not compete sites. intact cells, AIII stimulated inositol trisphosphate (IP3)...