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Revolution and empire on the northern frontier : Ira Allen of Vermont, 1751-1814.
Ira Allen was the quintessential late-eighteenth-century frontier entrepreneur. At the age of 21, he founded the Onion River Land Company, a loose family partnership designed to speculate in land titles to the disputed northern New England territory known as the New Hampshire Grants. By the time he turned 40, Allen claimed ownership of more than 100,000 choice acres along the eastern shore of Lake Champlain. Where most of his contemporaries saw an inhospitable wilderness, Allen anticipated a Champlain Valley of thriving communities, busy commercial centers, and extensive trade, all under his profitable control. Combining a romantic faith in the future of the backcountry with a relentless drive to acquire more land, he devoted his life to the elusive goal of prosperity in the area he called the country my soul delighted in. Yet there was more to Allen\u27s tangled career than land speculation and development schemes. He was a key figure in the oligarchy that preserved the independence of the fledgling State of Vermont during the American Revolution, serving as Vermont\u27s first Treasurer, Surveyor-General, and tireless ambassador-at-large. Absorbing the rhetoric of the national struggle against England, he adapted it for local application by writing books, pamphlets and broadsides that described Vermont as an unyielding opponent of foreign and domestic tyranny. After the war, Allen led the drive to create the University of Vermont, which he envisioned as a beacon of republican virtue and educational opportunity for the common man. When his Green Mountain empire collapsed, he planned revolutions in Canada and Mexico in desperate, unsuccessful attempts to regain his lost power and wealth. In his grand dreams, remarkable achievements, and ultimate failure, Ira Allen was an outstanding example of the backwoods leaders whose blending of personal and public priorities influenced the development of the American frontier from Maine to the Carolinas
Rosat observations of superflares on RS CVn systems
The following thesis involves the analysis of a number of X-ray observations of two RS CVn systems, made using the ROSAT satellite. These observations have revealed a number of long-duration flares lasting several days (much longer than previously observed in the X-ray energy band) and emitting energies which total a few percent of the available magnetic energy of the stellar system and thus far greater than previously encountered. Calculations based on the spectrally fitted parameters show that simple flare mechanisms and standard two-ribbon flare models cannot explain the observations satisfactorily and continued heating was observed during the outbursts. This is the first time that such departures from two-ribbon flare models have been identified unambiguously for such large flares, however for some of these outbursts the situation is complicated by the fact that other flaring activity may have been superimposed on the observed lightcurves. By analysing the general decay of the flares, loop heights were derived. Although these loop heights are dependendent on the amount of heating assumed, the calculations were performed for a wide range of reasonable heating values. For these cases the flare heights obtained for these outbursts were of the order of the inter-binary separation and inter-binary flares are suggested as the cause of the outbursts
CU Virginis - The First Stellar Pulsar
CU Virginis is one of the brightest radio emitting members of the magnetic
chemically peculiar (MCP) stars and also one of the fastest rotating. We have
now discovered that CU Vir is unique among stellar radio sources in generating
a persistent, highly collimated, beam of coherent, 100% polarised, radiation
from one of its magnetic poles that sweeps across the Earth every time the star
rotates. This makes the star strikingly similar to a pulsar. This similarity is
further strengthened by the observation that the rotating period of the star is
lengthening at a phenomenal rate (significantly faster than any other
astrophysical source - including pulsars) due to a braking mechanism related to
its very strong magnetic field.Comment: 10 pages including 2 figure
A Randomized Evaluation of Bispectral Index-Augmented Sedation Assessment in Neurological Patients
To assess whether monitoring sedation status using bispectral index (BIS) as an adjunct to clinical evaluation was associated with a reduction in the total amount of sedative drug used in a 12 h period
Synchrotron emission from the T Tauri binary system V773 Tau A
The pre-main sequence binary system V773 Tau A shows remarkable flaring
activity around periastron passage. Here, we present the observation of such a
flare at a wavelength of 3 mm (90 GHz) performed with the Plateau de Bure
Interferometer. We examine different possible causes for the energy losses
responsible for the e-folding time of 2.3 hours of that flare. We exclude
synchrotron, collisional, and inverse Compton losses because they are not
consistent with observational constraints, and we propose that the fading of
the emission is due to the leakage of electrons themselves at each reflection
between the two mirror points of the magnetic structure partially trapping
them. The magnetic structure compatible with both our leakage model and
previous observations is that of a helmet streamer that, as in the solar case,
can occur at the top of the X-ray-emitting, stellar-sized coronal loops of one
of the stars. The streamer may extend up to 20 R and interact with the corona
of the other star at periastron passage, causing recurring flares. The inferred
magnetic field strength at the two mirror points of the helmet streamer is in
the range 0.12 - 125 G, and the corresponding Lorentz factor, gamma, of the
partially trapped electrons is in the range 20 < gamma < 632. We therefore rule
out that the emission could be of gyro-synchrotron nature: the derived high
Lorentz factor proves that the nature of the emission at 90 GHz from this
pre-main binary system is synchrotron radiation.
Based on observations carried out with the IRAM Plateau de Bure
Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN
(Spain).Comment: 8 pages, 5 figures, A&A in pres
Continuous heating of a giant X-ray flare on Algol
Giant flares can release large amounts of energy within a few days: X-ray
emission alone can be up to ten percent of the star's bolometric luminosity.
These flares exceed the luminosities of the largest solar flares by many orders
of magnitude, which suggests that the underlying physical mechanisms supplying
the energy are different from those on the Sun. Magnetic coupling between the
components in a binary system or between a young star and an accretion disk has
been proposed as a prerequisite for giant flares. Here we report X-ray
observations of a giant flare on Algol B, a giant star in an eclipsing binary
system. We observed a total X-ray eclipse of the flare, which demonstrates that
the plasma was confined to Algol B, and reached a maximum height of 0.6 stellar
radii above its surface. The flare occurred around the south pole of Algol B,
and energy must have been released continously throughout its life. We conclude
that a specific extrastellar environment is not required for the presence of a
flare, and that the processes at work are therefore similar to those on the
Sun.Comment: Nature, Sept. 2 199
The Structure of Stellar Coronae in Active Binary Systems
A survey of 28 stars using EUV spectra has been conducted to establish the
structure of stellar coronae in active binary systems from the EMD, electron
densities, and scale sizes. Observations obtained by the EUVE during 9 years of
operation are included for the stars in the sample. EUVE data allow a
continuous EMD to be constructed in the range log T~5.6-7.4, using iron
emission lines. These data are complemented with IUE observations to model the
lower temperature range. Inspection of the EMD shows an outstanding narrow
enhancement, or ``bump'' peaking around log T~6.9 in 25 of the stars, defining
a fundamental coronal structure. The emission measure per unit stellar area
decreases with increasing orbital (or photometric) periods of the target stars;
stars in binaries generally have more material at coronal temperatures than
slowly rotating single stars. High electron densities (Ne>10^12 cm^-3) are
derived at ~10 MK for some targets, implying small emitting volumes. The
observations suggest the magnetic stellar coronae of these stars are consistent
with two basic classes of magnetic loops: solar-like loops with maximum
temperature around log T~6.3 and lower electron densities (Ne>10^9-10.5), and
hotter loops peaking around log T~6.9 with higher electron densities
(Ne>10^12). For the most active stars, material exists at much higher
temperatures (log T>6.9) as well. However, current ab initio stellar loop
models cannot reproduce such a configuration. Analysis of the light curves of
these systems reveals signatures of rotation of coronal material, as well as
apparent seasonal changes in the activity levels.Comment: 45 pages, 9 figures (with 20 eps files). Accepted for its publication
in ApJ
Automation Hooks Architecture Trade Study for Flexible Test Orchestration
We describe the conclusions of a technology and communities survey supported by concurrent and follow-on proof-of-concept prototyping to evaluate feasibility of defining a durable, versatile, reliable, visible software interface to support strategic modularization of test software development. The objective is that test sets and support software with diverse origins, ages, and abilities can be reliably integrated into test configurations that assemble and tear down and reassemble with scalable complexity in order to conduct both parametric tests and monitored trial runs. The resulting approach is based on integration of three recognized technologies that are currently gaining acceptance within the test industry and when combined provide a simple, open and scalable test orchestration architecture that addresses the objectives of the Automation Hooks task. The technologies are automated discovery using multicast DNS Zero Configuration Networking (zeroconf), commanding and data retrieval using resource-oriented Restful Web Services, and XML data transfer formats based on Automatic Test Markup Language (ATML). This open-source standards-based approach provides direct integration with existing commercial off-the-shelf (COTS) analysis software tools
Evaluating Active U: an Internet-mediated physical activity program.
Background:
Engaging in regular physical activity can be challenging, particularly during the winter months. To promote physical activity at the University of Michigan during the winter months, an eight-week Internet-mediated program (Active U) was developed providing participants with an online physical activity log, goal setting, motivational emails, and optional team participation and competition.
Methods:
This study is a program evaluation of Active U. Approximately 47,000 faculty, staff, and graduate students were invited to participate in the online Active U intervention in the winter of 2007. Participants were assigned a physical activity goal and were asked to record each physical activity episode into the activity log for eight weeks. Statistics for program reach, effectiveness, adoption, and implementation were calculated using the Re-Aim framework. Multilevel regression analyses were used to assess the decline in rates of data entry and goal attainment during the program, to assess the likelihood of joining a team by demographic characteristics, to test the association between various predictors and the number of weeks an individual met his or her goal, and to analyze server load.
Results:
Overall, 7,483 individuals registered with the Active U website (â16% of eligible), and 79% participated in the program by logging valid data at least once. Staff members, older participants, and those with a BMI < 25 were more likely to meet their weekly physical activity goals, and average rate of meeting goals was higher among participants who joined a competitive team compared to those who participated individually (IRR = 1.28, P < .001).
Conclusion:
Internet-mediated physical activity interventions that focus on physical activity logging and goal setting while incorporating team competition may help a significant percentage of the target population maintain their physical activity during the winter months
On the binary nature of 1RXS J162848.1-415241
We present spectroscopy of the optical counterpart to 1RXS J162848.1-41524,
also known as the microquasar candidate MCQC J162847-4152. All the data
indicate that this X-ray source is not a microquasar, and that it is a
single-lined chromospherically active binary system with a likely orbital
period of 4.9 days. Our analysis supports a K3IV spectral classification for
the star, which is dominant at optical wavelengths. The unseen binary component
is most likely a late-type (K7-M) dwarf or a white dwarf. Using the high
resolution spectra we have measured the K3 star's rotational broadening to be
vsini = 43 +/- 3 km/s and determined a lower limit to the binary mass ratio of
q(=M2/M1)>2.0. The high rotational broadening together with the strong CaII H &
K / Halpha emission and high-amplitude photometric variations indicate that the
evolved star is very chromospherically active and responsible for the
X-ray/radio emission.Comment: 15 pages, 5 figures, accepted for publication in Ap
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