3,582 research outputs found
Fission-induced plasmas
The possibility of creating a plasma from fission fragments, and to utilize the energy of the particles to create population inversion that would lead to laser action is investigated. An investigation was made of various laser materials which could be used for nuclear-pumped lasing. The most likely candidate for a fissioning material in the gaseous form is uranium hexafluoride - UF6, and experiments were performed to investigate materials that would be compatible with it. One of the central problems in understanding a fission-induced plasma is to obtain a model of the electron behavior, and some preliminary calculations are presented. In particular, the rates of various processes are discussed. A simple intuitive model of the electron energy distribution function is also shown. The results were useful for considering a mathematical model of a nuclear-pumped laser. Next a theoretical model of a (3)He-Ar nuclear-pumped laser is presented. The theory showed good qualitative agreement with the experimental results
3D Location of Circular and Spherical Features by Monocular Model-Based Vision
This paper addresses the mathematics for using monocular model-based vision to find the 3-D positions of circular and spherical model features, and, for the circular case, orientations as well. Monocular model-based vision here refers to the use of a single projective image of modeled objects to solve for the 3-D positions and orientations of the objects in the scene. The mathematics for solving 3-dimensional position and orientation of the object from matched model and image points/lines features are well known. However, no known paper addresses spherical features arid very few papers address the mathematics involving circular model features. This paper describes a novel closed-formed solution for the 3-D position and orientation of a circular features and the 3-D position of a spherical feature. The number of solutions for the circular case is found to be two in general, but there is only one solution when the surface normal of the circular feature passes through the center of projection. There is only one solution for the circular case. Advantages of this method are: (1) Handles spherical as well as circular features. (2) Closed-form solution. (3) Gives only the necessary number of solutions (no redundant solutions). (4) Simple mathematics involving 3-D analytic Geometry. (5) Geometrically intuitive
Anomalous U(1)_A and Electroweak Symmetry Breaking
We suggest a new mechanism for electroweak symmetry breaking in the
supersymmetric Standard Model. Our suggestion is based on the presence of an
anomalous U(1)_A gauge symmetry, which naturally arises in the four dimensional
superstring theory, and heavily relies on the value of the corresponding
Fayet-Illiopoulos \xi-term.Comment: Latex, 11 pages, discussions and references adde
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A case series of primary cutaneous coccidioidomycosis after a record-breaking rainy season.
Studies of new media radiation induced laser
Various lasants were investigated especially, 2-iodohepafluoropropane (i-C3F7I) for the direct solar pumped lasers. Optical pumping of iodine laser was achieved using a small flashlamp. Using i-C3F7I as a laser gain medium, threshold inversion density, small signal gain, and laser performance at the elevated temperature were measured. The experimental results and analysis are presented. The iodine laser kinetics of the C3F7I and IBr system were numerically simulated. The concept of a direct solar-pumped laser amplifier using (i-C3F7I) as the laser material was evaluated and several kinetic coefficients for i-C3F7I laser system were reexamined. The results are discussed
Correlation between plasma phospholipid transfer protein activity and low density lipoprotein subfractions pattern in subjects with type 2 diabetes mellitus
published_or_final_versio
Multiple cations interdiffusion in In0.53Ga0.47As/In0.52Al0.48As quantum well
Theme: Infrared applications of semiconductors: materials, processing and devicesMultiple cations interdiffusion in Ino.53Gao.47As/Ino.52Alo.48As quantum well (QW) structure is investigated by using the model of expanded form of Fick's second law. The model is fitted to the measured concentration data in order to determine their diffusion coefficients. Once the concentration distribution is obtained, the types of strain and their variation across the QW can be determined, thus the subbands and transitions can be gathered. Result shows interesting phenomena due to this three species interdiffusion.published_or_final_versio
Association between serum concentrations of soluble lectin-like oxidized low density lipoprotein receptor-1 and serum amyloid A in type 2 diabetes
This journal suppl. entitled: Abstracts of the 10th International Diabetes Federation-Western Pacific Region Congress and the 6th AASD Scientific MeetingPosters: no. PO020BACKGROUND: Lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) mediates the uptake of oxidized LDL in endothelial cells and macrophages, and has been implicated in the pathogenesis of vascular inflammation and atherosclerosis. The extracellular domain of LOX-1 can be proteolytically cleaved and released as a soluble form (sLOX-1). It has been suggested that circulating level of sLOX-1 reflects LOX-1 expression and can act as a biomarker. LOX-1 expression is inducible and recent experimental data have shown that serum amyloid A (SAA), an acute phase protein, can induce LOX-1 expression in macrophages in vitro. Since type 2 diabetes is associated with subclinical inflammation, we have evaluated whether serum sLOX-1 level is ...postprin
Nitrate and ammonium lead to distinct global dynamic phosphorylation patterns when resupplied to nitrogen-starved Arabidopsis seedlings
Nitrogen is an essential macronutrient for plant growth and development. Inorganic nitrogen and its assimilation products control various metabolic, physiological and developmental processes. Although the transcriptional responses induced by nitrogen have been extensively studied in the past, our work here focused on the discovery of candidate proteins for regulatory events that are complementary to transcriptional changes. Most signaling pathways involve modulation of protein abundance and/or activity by protein phosphorylation. Therefore, we analyzed the dynamic changes in protein phosphorylation in membrane and soluble proteins from plants exposed to rapid changes in nutrient availability over a time course of 30 min. Plants were starved of nitrogen and subsequently resupplied with nitrogen in the form of nitrate or ammonium. Proteins with maximum change in their phosphorylation level at up to 5 min after nitrogen resupply (fast responses) included GPI-anchored proteins, receptor kinases and transcription factors, while proteins with maximum change in their phosphorylation level after 10 min of nitrogen resupply (late responses) included proteins involved in protein synthesis and degradation, as well as proteins with functions in central metabolism and hormone metabolism. Resupply of nitrogen in the form of nitrate or ammonium resulted in distinct phosphorylation patterns, mainly of proteins with signaling functions, transcription factors and transporters
Serum Level of Soluble Receptor for Advanced Glycation End Products Is Associated with A Disintegrin And Metalloproteinase 10 in Type 1 Diabetes
Background
The receptor for advanced glycation end products (RAGE) is involved in the pathogenesis of diabetic complications, and soluble forms of the receptor (sRAGE) can counteract the detrimental action of the full-length receptor by acting as decoy. Soluble RAGE is produced by alternative splicing [endogenous secretory RAGE (esRAGE)] and/or by proteolytic cleavage of the membrane-bound receptor. We have investigated the role of A Disintegrin And Metalloproteinase 10 (ADAM10) in the ectodomain shedding of RAGE.
Methods
Constitutive and insulin-induced shedding of RAGE in THP-1 macrophages by ADAM10 was evaluated using an ADAM10-specific metalloproteinase inhibitor. Serum ADAM10 level was measured in type 1 diabetes and control subjects, and the association with serum soluble RAGE was determined. Serum total sRAGE and esRAGE were assayed by ELISA and the difference between total sRAGE and esRAGE gave an estimated measure of soluble RAGE formed by cleavage (cRAGE).
Results
RAGE shedding (constitutive and insulin-induced) was significantly reduced after inhibition of ADAM10 in macrophages, and insulin stimulated ADAM10 expression and activity. Diabetic subjects have higher serum total sRAGE and esRAGE (p<0.01) than controls, and serum ADAM10 was also increased (p<0.01). Serum ADAM10 correlated with serum cRAGE in type 1 diabetes (r = 0.40, p<0.01) and in controls (r = 0.31. p<0.01) but no correlations were seen with esRAGE. The association remained significant after adjusting for age, gender, BMI, smoking status and HbA1c.
Conclusion
Our data suggested that ADAM10 contributed to the shedding of RAGE. Serum ADAM10 level was increased in type 1 diabetes and was a significant determinant of circulating cRAGE.published_or_final_versio
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