2,351 research outputs found
Mechanisms and Observations of Coronal Dimming for the 2010 August 7 Event
Coronal dimming of extreme ultraviolet (EUV) emission has the potential to be
a useful forecaster of coronal mass ejections (CMEs). As emitting material
leaves the corona, a temporary void is left behind which can be observed in
spectral images and irradiance measurements. The velocity and mass of the CMEs
should impact the character of those observations. However, other physical
processes can confuse the observations. We describe these processes and the
expected observational signature, with special emphasis placed on the
differences. We then apply this understanding to a coronal dimming event with
an associated CME that occurred on 2010 August 7. Data from the Solar Dynamics
Observatory's (SDO) Atmospheric Imaging Assembly (AIA) and EUV Variability
Experiment (EVE) are used for observations of the dimming, while the Solar and
Heliospheric Observatory's (SOHO) Large Angle and Spectrometric Coronagraph
(LASCO) and the Solar Terrestrial Relations Observatory's (STEREO) COR1 and
COR2 are used to obtain velocity and mass estimates for the associated CME. We
develop a technique for mitigating temperature effects in coronal dimming from
full-disk irradiance measurements taken by EVE. We find that for this event,
nearly 100% of the dimming is due to mass loss in the corona
Practical implementation of an interior point nonmonotone line search filter method
Versão não definitiva do artigoHere we present a primal-dual interior point nonmonotone line search
filter method for nonlinear programming. The filter relies on three
measures, the feasibility, the centrality and the optimality
presented in the optimality conditions, considers relaxed
acceptability criteria for the step size and includes a feasibility
restoration phase. The evaluation of the method is until now made on
small problems and a comparison is provided with a merit function
approach
To Kick Against the Pricks: An Examination of the Oresteia and the Acts of the Apostles
The major themes found in the Oresteia and the books of Luke and Acts of the Apostles are compared. By focusing on the similarities found in the themes of Justice, Religion, and New versus Old, the reader may determine if the phrase in question is being used as a literary allusion in the book of Acts of the Apostles to the Oresteia trilogy. The author believes this to be the case and believes that to arrive at a full understanding of the literary meaning of the phrase in question, an understanding of the major themes of the Oresteia is necessary
A Droplet State in an Interacting Two-Dimensional Electron System
It is well known that the dielectric constant of two-dimensional (2D)
electron system goes negative at low electron densities. A consequence of the
negative dielectric constant could be the formation of the droplet state. The
droplet state is a two-phase coexistence region of high density liquid and low
density "gas". In this paper, we carry out energetic calculations to study the
stability of the droplet ground state. The possible relevance of the droplet
state to recently observed 2D metal-insulator transition is also discussed.Comment: 4 pages, 4 figures. To appear in Phys. Rev. B (Rapid Communications
A Comparison of Arch Height Index Measures Between Collegiate Basketball and National Basketball Association Players
The rate of game related basketball injuries is 2xs greater in professionals than collegiate players and the most common injuries occur in the lower extremity. Arch mechanics are often cited as a related factor and the Arch Height Index Measurement System (AHIMS) is a reliable and valid system for quantifying mobility. However, normative or comparative values for basketball athletes have not been reported.https://ecommons.udayton.edu/dpt_symposium/1028/thumbnail.jp
Effects of extraction conditions on antioxidant properties of sapodilla fruit (Manilkara zapota)
This study investigated the effects of different percentages of ethanol (0 - 100%), extraction times (1 - 5 h) and temperatures (25 - 60°C) on total phenolic content (TPC) and antioxidant activity (AA) of sapodilla pulp and peel. TPC was determined by Folin-Ciocalteu reagent method, while AA was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, 2,2-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay, ferric reducing antioxidant power (FRAP) assay and ß-carotene bleaching (BCB) assay. Based on the optimal extraction conditions used, sapodilla pulp extract had TPC of 3.89 mg GAE/g, 63.20% of DPPH scavenging activity, 4.30% of ABTS scavenging activity, 19.17% of BCB activity, and FRAP value of 15.24 mg TE/g; while its peel extract had TPC of 9.23 mg GAE/g, 92.95% of DPPH scavenging activity, 5.36% of ABTS scavenging activity, 8.14% of BCB activity, and 27.85 mg TE/g (FRAP value). Using the optimal extraction conditions for sapodilla pulp (40% ethanol as extraction solvent that extracted at 60°C for 4 h) and sapodilla peel (80% ethanol and 2 h extraction time at 40°C), highest antioxidants can be extracted from the pulp and peel
High energy Coulomb-scattered electrons for relativistic particle beam diagnostics
A new system used for monitoring energetic Coulomb-scattered electrons as the
main diagnostic for accurately aligning the electron and ion beams in the new
Relativistic Heavy Ion Collider (RHIC) electron lenses is described in detail.
The theory of electron scattering from relativistic ions is developed and
applied to the design and implementation of the system used to achieve and
maintain the alignment. Commissioning with gold and 3He beams is then described
as well as the successful utilization of the new system during the 2015 RHIC
polarized proton run. Systematic errors of the new method are then estimated.
Finally, some possible future applications of Coulomb-scattered electrons for
beam diagnostics are briefly discussed.Comment: 16 pages, 23 figure
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