Probing the Role of Magnetic-Field Variations in NOAA AR 8038 in Producing Solar Flare and CME on 12 May 1997

We carried out a multi-wavelength study of a CME and a medium-size 1B/C1.3 flare occurring on 12 May 1997. We present the investigation of magnetic-field variations in the NOAA Active Region 8038 which was observed on the Sun during 7--16 May 1997. Analyses of H{\alpha} filtergrams and MDI/SOHO magnetograms revealed continual but discrete surge activity, and emergence and cancellation of flux in this active region. The movie of these magnetograms revealed two important results that the major opposite polarities of pre-existing region as well as in the emerging flux region (EFR) were approaching towards each other and moving magnetic features (MMF) were ejecting out from the major north polarity at a quasi-periodicity of about ten hrs during 10--13 May 1997. These activities were probably caused by the magnetic reconnection in the lower atmosphere driven by photospheric convergence motions, which were evident in magnetograms. The magnetic field variations such as flux, gradient, and sunspot rotation revealed that free energy was slowly being stored in the corona. The slow low-layer magnetic reconnection may be responsible for this storage and the formation of a sigmoidal core field or a flux rope leading to the eventual eruption. The occurrence of EUV brightenings in the sigmoidal core field prior to the rise of a flux rope suggests that the eruption was triggered by the inner tether-cutting reconnection, but not the external breakout reconnection. An impulsive acceleration revealed from fast separation of the H{\alpha} ribbons of the first 150 seconds suggests the CME accelerated in the inner corona, which is consistent with the temporal profile of the reconnection electric field. In conclusion, we propose a qualitative model in view of framework of a solar eruption involving, mass ejections, filament eruption, CME, and subsequent flare.Comment: 8 figures, accepted for publication in Solar Physic

Electric current circuits in astrophysics

Cosmic magnetic structures have in common that they are anchored in a dynamo, that an external driver converts kinetic energy into internal magnetic energy, that this magnetic energy is transported as Poynting fl ux across the magnetically dominated structure, and that the magnetic energy is released in the form of particle acceleration, heating, bulk motion, MHD waves, and radiation. The investigation of the electric current system is particularly illuminating as to the course of events and the physics involved. We demonstrate this for the radio pulsar wind, the solar flare, and terrestrial magnetic storms

Origins of the Ambient Solar Wind: Implications for Space Weather

The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its ability to forecast how variations in the solar wind (i.e., fast and slow wind streams) impact the Earth. Although the last few decades have seen significant progress in observations and modeling, we still do not have a complete understanding of the relevant physical processes, nor do we have a quantitatively precise census of which coronal structures contribute to specific types of solar wind. Fast streams are known to be connected to the central regions of large coronal holes. Slow streams, however, appear to come from a wide range of sources, including streamers, pseudostreamers, coronal loops, active regions, and coronal hole boundaries. Complicating our understanding even more is the fact that processes such as turbulence, stream-stream interactions, and Coulomb collisions can make it difficult to unambiguously map a parcel measured at 1 AU back down to its coronal source. We also review recent progress -- in theoretical modeling, observational data analysis, and forecasting techniques that sit at the interface between data and theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue connected with a 2016 ISSI workshop on "The Scientific Foundations of Space Weather." 44 pages, 9 figure

Involking silvern voices in healthcare : transforming practice by engaging older adults in collaborative partnerships

Canada's population is aging. This growing trend will ultimately have an impact on nursing practice as older individuals continue to seek healthcare services. Nurses must be able to work in collaboration with the older population to provide quality care. This action research study explored participative healthcare from an older adult's perspective. This study revealed that older adults prefer to be active participants in their care. The major theme that emerged was true partnership. Three sub-themes that emerged were communication, respect, and trust. These three sub-themes work in unity to contribute to a healthcare experience that exemplifies true partnerships. This study proposes a definition of true partnership as being open to and inviting mutual communication in an atmosphere that encourages equity sharing of information contributing to respect and the development of trust that results in confident collaboration in care

State-of-the-art in Micro-Hotplates

Micro-hotplate (MHP) is a microheater fabricated with integrated circuit (IC) technology and micromachining on silicon substrate. Because of low power consumption, fast thermal response, and ability of integrating with ICs, the MHP is a very useful device to develop microsensors and biochips, and to study heat transfer in microscale. The state-of-the art in MHP and future directions are reviewed in this paper

Measuring disease activity in psoriatic arthritis

10.1155/2012/839425International Journal of Rheumatology201283942

Integration of horizontal carbon nanotube devices on silicon substrate using liquid evaporation

This paper presents a process to fabricate horizontal carbon nanotube (CNT) components with controllable orientations and positions on silicon substrate. This process makes use of capillary effect to pull down inclined CNT bundles. Liquid wettable to both CNT bundles and silicon substrates was used to generate attractive force to level the CNT. The final orientation of CNT bundles was determined by the initial inclination of the CNT grown. The geometric patterns of catalyst film have significant effect on the initial inclination. Using the electron-shading effect, specially designed catalyst patterns and the liquid evaporation process, we demonstrated good control on the positions, the dimensions, and the orientations of on-chip grown CNT, thus facilitating the on-chip integration of CNT components. © 2010 IEEE

Towards future VLSI interconnects using aligned carbon nanotubes

The copper interconnects cannot keep pace with the IC interconnect requirements as the feature size continues to scale down to nanoscale. Theoretical works predicted that carbon nanotube (CNT) is more superior than copper for future VLSI interconnects in terms of electrical conductivity, thermal management and reliability. Technology breakthroughs are required to bridge the gaps between the theoretical predictions and what is achievable with current CNT technology. In this paper, we shall describe our experimental efforts on the controlled growth of aligned CNTs; the integrations of CNT interconnects with IC technology; and the electrical characterization of the CNT interconnect. We also present the electro-migration test result of CNT-based interconnects to demonstrate the potential of CNT as robust VLSI interconnects. We hope our works provide useful data on the potential of CNT for VLSI interconnect applications. © 2011 IEEE