ABSTRACT
We present a statistical study of Jupiter's disk X-ray emissions using 19 years of Chandra X-Ray Observatory (CXO) observations. Previous work has suggested that these emissions are consistent with solar X-rays elastically scattered from Jupiter's upper atmosphere. We showcase a new pulse invariant (PI) filtering method that minimizes instrumental effects which may produce unphysical trends in photon counts across the nearly two-decade span of the observations. We compare the CXO results with solar X-ray flux data from the Geostationary Operational Environmental Satellites X-ray Sensor for the wavelength band 1-8 Å (long channel), to quantify the correlation between solar activity and Jovian disk counts. We find a statistically significant Pearson's Correlation Coefficient of 0.9, which confirms that emitted Jovian disk X-rays are predominantly governed by solar activity. We also utilize the high spatial resolution of the High Resolution Camera Instrument on-board the CXO to map the disk photons to their positions on Jupiter's surface. Voronoi tessellation diagrams were constructed with the Juno Reference Model through Perijove 9 internal field model overlaid to identify any spatial preference of equatorial photons. After accounting for area and scattering across the curved surface of the planet, we find a preference of Jovian disk emission at 2-3.5 Gauss surface magnetic field strength. This suggests that a portion of the disk X-rays may be linked to processes other than solar scattering: the spatial preference associated with magnetic field strength may imply increased precipitation from the radiation belts, as previously postulated.
ABSTRACT
For almost 20 years the physical nature of globally propagating waves in the solar corona (commonly called "EIT waves") has been controversial and subject to debate. Additional theories have been proposed over the years to explain observations that did not agree with the originally proposed fast-mode wave interpretation. However, the incompatibility of observations made using the Extreme-ultraviolet Imaging Telescope (EIT) onboard the Solar and Heliospheric Observatory with the fast-mode wave interpretation was challenged by differing viewpoints from the twin Solar Terrestrial Relations Observatory spacecraft and data with higher spatial and temporal resolution from the Solar Dynamics Observatory. In this article, we reexamine the theories proposed to explain EIT waves to identify measurable properties and behaviours that can be compared to current and future observations. Most of us conclude that the so-called EIT waves are best described as fast-mode large-amplitude waves or shocks that are initially driven by the impulsive expansion of an erupting coronal mass ejection in the low corona.
ABSTRACT
A series of N-alkyl-N-arylmethylpiperidin-4-amines have been prepared and are demonstrated to be inhibitors of both serotonin and norepinephrine reuptake.
Subject(s)
Norepinephrine/antagonists & inhibitors , Piperidines/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Piperidines/chemistry , Selective Serotonin Reuptake Inhibitors/chemistry , Structure-Activity RelationshipABSTRACT
A series of benzothienyloxy propylamines have been prepared and are demonstrated to be inhibitors of both serotonin and norepinephrine reuptake.
Subject(s)
Adrenergic Uptake Inhibitors/chemical synthesis , Antidepressive Agents/chemical synthesis , Norepinephrine/antagonists & inhibitors , Propylamines/chemical synthesis , Selective Serotonin Reuptake Inhibitors/chemical synthesis , Thiophenes/chemical synthesis , Adrenergic Uptake Inhibitors/pharmacology , Antidepressive Agents/pharmacology , Dopamine Plasma Membrane Transport Proteins , Humans , In Vitro Techniques , Membrane Glycoproteins/metabolism , Membrane Transport Proteins/metabolism , Microsomes, Liver/metabolism , Nerve Tissue Proteins/metabolism , Norepinephrine/metabolism , Norepinephrine Plasma Membrane Transport Proteins , Propylamines/pharmacology , Serotonin Plasma Membrane Transport Proteins , Selective Serotonin Reuptake Inhibitors/pharmacology , Stereoisomerism , Structure-Activity Relationship , Symporters/metabolism , Thiophenes/pharmacologyABSTRACT
A series of naphthalenyloxy-arylpropylamines have been prepared and are demonstrated to be inhibitors of both serotonin and norepinephrine reuptake. One member of this series, duloxetine (Cymbalta) has proven to be effective in clinical trials for the treatment of depression.
Subject(s)
Norepinephrine/antagonists & inhibitors , Selective Serotonin Reuptake Inhibitors/chemistry , Thiophenes/chemistry , Antidepressive Agents/chemical synthesis , Antidepressive Agents/therapeutic use , Binding Sites , Clinical Trials as Topic , Depressive Disorder/drug therapy , Duloxetine Hydrochloride , Humans , Kinetics , Selective Serotonin Reuptake Inhibitors/chemical synthesis , Selective Serotonin Reuptake Inhibitors/pharmacology , Structure-Activity Relationship , Thiophenes/therapeutic useABSTRACT
D-Amino acid oxidase activity was demonstrated in peroxisomes of rat liver using unfixed cryostat sections and a histochemical technique using cerium ions as capture reagent for hydrogen peroxide and diaminobenzidine, cobalt ions and exogenous hydrogen peroxide to visualize the final reaction product for light microscopical analysis. Cytophotometric analysis of liver sections revealed similar zero-order reaction velocities of D-amino acid oxidase with activity twice as high in periportal areas as in pericentral areas of liver lobuli when using either D-proline or D,L-thiazolidine-2-carboxylic acid as substrates. On the other hand, a 4-5 times higher KM value was found for D-proline than for D,L-thiazolidine-2-carboxylic acid. The KM values in periportal and pericentral areas were similar for each substrate. These findings support the suggestion that the physiological substrate for D-amino acid oxidase may be D,L-thiazolidine-2-carboxylic acid, the adduct of cysteamine and glyoxylic acid. D-Amino acid oxidase may play a role in vivo in the production of oxalate which may participate in metabolic control processes as an intracellular messenger molecule.
Subject(s)
D-Amino-Acid Oxidase/metabolism , Liver/enzymology , Animals , Histocytochemistry , Kinetics , Male , Proline/analogs & derivatives , Proline/metabolism , Rats , Rats, Wistar , Substrate Specificity , ThiazolidinesABSTRACT
A series of 5-acyl-3-substituted-benzofuran-2(3H)-ones and their respective ring-opened o-hydroxy acids were synthesized. The antiinflammatory activity was evaluated in terms of their ability to improve adjuvant induced arthritis in rats. Their effect on the production of both cyclooxygenase (CO) and lipoxygenase (LO) metabolites of arachidonic acid in guinea pig peritoneal polymorphonuclear neutrophils (PMNs) was also examined. No correlation between the antiinflammatory activity and increasing stability of the lactones could be found. The degree of activity in general shown by the benzofuranones was similar to that of their corresponding o-hydroxy acids. This, coupled with the evidence from studies on opening of the lactone ring, suggests an in vivo transformation of the former into the latter. Benzofuranones displayed a dual inhibition of CO and LO products, while a moderate reduction in CO metabolites was shown by their acids.