3,036 research outputs found
Relevance of ERTS-1 to the State of Ohio
The author has identified the following significant results. During the first year of project effort the ability of ERTS-1 imagery to be used for mapping and inventorying strip-mined areas in southeastern Ohio, the potential of using ERTS-1 imagery in water quality and coastal zone management in the Lake Erie region, and the extent that ERTS-1 imagery could contribute to localized (metropolitan/urban), multicounty, and overall state land use needs were experimentally demonstrated and reported as significant project results
Resource management implications of ERTS-1 data to Ohio
Initial experimental analysis of ERTS-1 imagery has demonstrated that remote sensing from space is a means of delineating and inventorying Ohio's strip-mined areas, detecting power plant smoke plumes, and proving the data necessary for periodically compiling land use maps for the entire state. The nature and extent of these problems throughout Ohio, how ERTS data can contribute to their solution, and estimates of the long term significance of these initial findings to overall resource management interests in Ohio are summarized
Age-related shifts in bacterial diversity in a reef coral
This study investigated the relationship between microbial communities in differently sized colonies of the massive coral Coelastrea aspera at Phuket, Thailand where colony size could be used as a proxy for age. Results indicated significant differences between the bacterial diversity (ANOSIM, R = 0.76, p = 0.001) of differently sized colonies from the same intertidal reef habitat. Juvenile and small colonies (28 cm mean diam). Bacterial diversity increased in a step-wise pattern from juvenilessmallmedium colonies, which was then followed by a slight decrease in the two largest size classes. These changes appear to resemble a successional process which occurs over time, similar to that observed in the ageing human gut. Furthermore, the dominant bacterial ribotypes present in the tissues of medium and large sized colonies of C. aspera, (such as Halomicronema, an Oscillospira and an unidentified cyanobacterium) were also the dominant ribotypes found within the endolithic algal band of the coral skeleton; a result providing some support for the hypothesis that the endolithic algae of corals may directly influence the bacterial community present in coral tissues.Barbara Brown recieved funding from the Leverhulme Trust [www.leverhulme.ac.uk]; Grant number: EM-2013-058. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Two-scale structure of the electron dissipation region during collisionless magnetic reconnection
Particle in cell (PIC) simulations of collisionless magnetic reconnection are
presented that demonstrate that the electron dissipation region develops a
distinct two-scale structure along the outflow direction. The length of the
electron current layer is found to decrease with decreasing electron mass,
approaching the ion inertial length for a proton-electron plasma. A surprise,
however, is that the electrons form a high-velocity outflow jet that remains
decoupled from the magnetic field and extends large distances downstream from
the x-line. The rate of reconnection remains fast in very large systems,
independent of boundary conditions and the mass of electrons.Comment: Submitted to Physical Review Letters, 4 pages, 4 figure
2MASS J06164006-6407194: The First Outer Halo L Subdwarf
We present the serendipitous discovery of an L subdwarf, 2MASS
J06164006-6407194, in a search of the Two Micron All Sky Survey for T dwarfs.
Its spectrum exhibits features indicative of both a cool and metal poor
atmosphere including a heavily pressured-broadened K I resonant doublet, Cs I
and Rb I lines, molecular bands of CaH, TiO, CrH, FeH, and H2O, and enhanced
collision induced absorption of H2. We assign 2MASS 0616-6407 a spectral type
of sdL5 based on a comparison of its red optical spectrum to that of near
solar-metallicity L dwarfs. Its high proper motion (mu =1.405+-0.008 arcsec
yr-1), large radial velocity (Vrad = 454+-15 km s-1), estimated uvw velocities
(94, -573, 125) km s-1 and Galactic orbit with an apogalacticon at ~29 kpc are
indicative of membership in the outer halo making 2MASS 0616-6407 the first
ultracool member of this population.Comment: Accepted for publication in Ap
Self-Regulation of Solar Coronal Heating Process via Collisionless Reconnection Condition
I propose a new paradigm for solar coronal heating viewed as a
self-regulating process keeping the plasma marginally collisionless. The
mechanism is based on the coupling between two effects. First, coronal density
controls the plasma collisionality and hence the transition between the slow
collisional Sweet-Parker and the fast collisionless reconnection regimes. In
turn, coronal energy release leads to chromospheric evaporation, increasing the
density and thus inhibiting subsequent reconnection of the newly-reconnected
loops. As a result, statistically, the density fluctuates around some critical
level, comparable to that observed in the corona. In the long run, coronal
heating can be represented by repeating cycles of fast reconnection events
(nano-flares), evaporation episodes, and long periods of slow magnetic stress
build-up and radiative cooling of the coronal plasma.Comment: 4 pages; Phys. Rev. Lett., in pres
Collisionless Magnetic Reconnection via Alfven Eigenmodes
We propose an analytic approach to the problem of collisionless magnetic
reconnection formulated as a process of Alfven eigenmodes' generation and
dissipation. Alfven eigenmodes are confined by the current sheet in the same
way that quantum mechanical waves are confined by the tanh^2 potential. The
dynamical time scale of reconnection is the system scale divided by the
eigenvalue propagation velocity of the n=1 mode. The prediction of the n=1 mode
shows good agreement with the in situ measurement of the
reconnection-associated Hall fields
Threading, Stitching, and Storytelling: Using CBPR and Blackfoot Knowledge and Cultural Practices to Improve Domestic Violence Services for Indigenous Women
This article discusses a community-based participatory research (CBPR) project at two women’s emergency shelters in rural southwestern Alberta. The CBPR project aimed to improve shelter services on and off reserve in our area by engaging the voices of Indigenous women who had experienced domestic violence. The project’s methods were participatory appraisal and arts-based work re-imagined through Blackfoot cultural practices of storytelling and shawl making. The project created a rare safe space where thirteen Blackfoot women emphasised DV services should provide opportunities to connect with family and community and role model Blackfoot knowledge. Role modelling traditional knowledges aids developing life and parenting skills, opening up pathways for Indigenous women to more positive, secure futures. These women’s recommendations impelled this article to challenge the individualized case management model and discourses of cultural competence dominating Canadian DV services, which isolate and marginalize Indigenous women when they seek help. We highlight resources existing in Blackfoot communities to manage and prevent violence by protecting and facilitating Indigenous women’s connections to their communities and cultures, and offer ways to utilize these more effectively in service settings
Effective dynamics using conditional expectations
The question of coarse-graining is ubiquitous in molecular dynamics. In this
article, we are interested in deriving effective properties for the dynamics of
a coarse-grained variable , where describes the configuration of
the system in a high-dimensional space , and is a smooth function
with value in (typically a reaction coordinate). It is well known that,
given a Boltzmann-Gibbs distribution on , the equilibrium
properties on are completely determined by the free energy. On the
other hand, the question of the effective dynamics on is much more
difficult to address. Starting from an overdamped Langevin equation on , we propose an effective dynamics for using conditional
expectations. Using entropy methods, we give sufficient conditions for the time
marginals of the effective dynamics to be close to the original ones. We check
numerically on some toy examples that these sufficient conditions yield an
effective dynamics which accurately reproduces the residence times in the
potential energy wells. We also discuss the accuracy of the effective dynamics
in a pathwise sense, and the relevance of the free energy to build a
coarse-grained dynamics
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