786 research outputs found
Report : Petition of S. Thomasson
Report : Petition of S. Thomasson. [2826] Creek war of 1836; Georgia; Cherokee disturbances of 1838
Enhancement of magnetic fields arising from galactic encounters
Galactic encounters are usually marked by a substantial increase of
synchrotron emission of the interacting galaxies compared to the typical
emission from similar isolated galaxies. This is believed to be associated with
an increase of the star formation rate and the associated turbulent magnetic
fields. The regular magnetic field is usually believed to decrease. We consider
a simple, however rather realistic, mean-field galactic dynamo model where the
effects of small-scale generation are represented by random injections of
magnetic field from star forming regions. We represent an encounter by the
introduction of large-scale streaming velocities and by an increase in
small-scale magnetic field injections. The latter describes the effect of an
increase of the star formation rate caused by the encounter. We demonstrate
that large-scale streaming, with associated deviations in the rotation curve,
can result in an enhancement of the anisotropic turbulent (ordered) magnetic
field strength, mainly along the azimuthal direction, leading to a significant
temporary increase of the total magnetic energy during the encounter; the
representation of an increase in star formation rate has an additional strong
effect. In contrast to expectations, the large-scale (regular) magnetic field
structure is not significantly destroyed by the encounter. It may be somewhat
weakened for a relatively short period, and its direction after the encounter
may be reversed. The encounter causes enhanced total and polarized emission
without increase of the regular magnetic field strength. The increase of
synchrotron emission caused by the large-scale streaming can be comparable to
the effect of the increase of the star formation rate, depending on the choice
of parameters.The effects of the encounter on the total magnetic field energy
last only slightly longer than the duration of the encounter (ca. 1 Gyr).Comment: 9 pages, 11 figures minor changes in response to referee's
comments+linguistic/stylistic change
Heat & Frost Insulators & Allied Workers Loc. 16 v. Lab. Comm’r; Univ. of Nev., Reno; & CORE Constr., 134 Nev. Adv. Op. 1 (Jan. 4, 2018)
NRS 233B.130(2)(c)(1)’s service requirement is mandatory and jurisdictional. Further, under NRS 233B.130(5), the district court has jurisdiction to extend time for service for good cause, either before or after the 45-day service period has run
The Formation of Ultra-Compact Dwarf Galaxies
Recent spectroscopic observations of galaxies in the Fornax-Cluster reveal
nearly unresolved `star-like' objects with red-shifts appropriate to the
Fornax-Cluster. These objects have intrinsic sizes of about 100 pc and absolute
B-band magnitudes in the range -14 < M_B < -11.5 mag and lower limits for the
central surface brightness mu_B > 23 mag/arcsec^2 (Phillipps et al. 2001), and
so appear to constitute a new population of ultra-compact dwarf galaxies
(UCDs). Such compact dwarfs were predicted to form from the amalgamation of
stellar super-clusters (Kroupa 1998), which are rich aggregates of young
massive star clusters (YMCs) that can form in collisions between gas-rich
galaxies. Here we present the evolution of super-clusters in a tidal field. The
YMCs merge on a few super-cluster crossing times. Super-clusters that are
initially as concentrated and massive as knot~S in the interacting Antennae
galaxies (Whitmore et al. 1999) evolve to merger objects that are long-lived
and show properties comparable to the newly discovered UCDs. Less massive
super-clusters resembling knot 430 in the Antennae may evolve to omega-Cen-type
systems. Low-concentration super-clusters are disrupted by the tidal field,
dispersing their surviving star clusters while the remaining merger objects
rapidly evolve into the mu_B-M_B region populated by low-mass Milky-Way dSph
satellites.Comment: MNRAS, accepted, 10 pages, 10 figure
Abdominal intercostal hernia: a rare complication after blunt trauma.
Abdominal intercostal hernia (AIH) is uncommonly reported in the literature with only 20 cases reported to date.1–3 We report a case of a delayed incarcerated AIH secondary to blunt trauma from a motor vehicle accident in which the colon and diaphragm herniated through an associated chest defect that was repaired successfully through a transabdominal approach using primary repair of the defect in combination with onlay porcine patch reinforcement
X-ray polarimetry with an active-matrix pixel proportional counter
We report the first results from an X-ray polarimeter with a micropattern gas
proportional counter using an amorphous silicon active matrix readout. With
100% polarized X-rays at 4.5 keV, we obtain a modulation factor of 0.33 +/-
0.03, confirming previous reports of the high polarization sensitivity of a
finely segmented pixel proportional counter. The detector described here has a
geometry suitable for the focal plane of an astronomical X-ray telescope.
Amorphous silicon readout technology will enable additional extensions and
improvements.Comment: 4 pages, 4 figures, 1 tabl
Enablers and barriers in German online food retailing
This article discusses enablers and barriers in online food retailing in Germany. The German food retail sector is one of the largest in Europe; however, its online or Internet provision for customers lags way behind the United Kingdom and France. Prior research has considered the demand-consumer side of this dyad; however, little has been done on the online food supply-retail side. This article addresses that gap through exploratory empirical research with three retailers, three logistics service providers, and a marketing agency. There is good potential in this market but costs of fulfilment and service quality currently represent major barriers
Money and mental contents
It can be hard to see where money fits in the world. Money seems both real and imaginary, since it has obvious causal powers, but is also, just as obviously, something humans have just made up. Recent philosophical accounts of money have declared it to be real, but for very different reasons. John Searle and Francesco Guala disagree over whether money is just whatever acts like money, or just whatever people believe to be money. In developing their accounts of institutions as a part of social reality, each uses money as a paradigm institution, but they disagree on how institutions exist. Searle argues that the institution of money belongs to an ontological level separate from the physical world, held up by the collective intentions of a group, while Guala claims that money is a part of the ordinary physical world and is just whatever performs a “money-like function” in a group, regardless of what that group believes about it. Here, we argue that any purely functional account like Guala’s will be unable to capture the distinctive phenomenon of money, since monetary transactions are defined by the attitudes transactors hold toward them. Money will be obscured or misidentified if defined functionally. As we go on to show by examining recent work by Smit et al., belief in money does not require taking on all of Searle’s ontological commitments, but money and mental contents will stand or fall together
Formation of massive clouds and dwarf galaxies during tidal encounters
Gerola et al. (1983) propose that isolated dwarf galaxies can form during galaxy interactions. As evidence of this process, Mirabel et al. (1991) find 10(exp 9) solar mass clouds and star formation complexes at the outer ends of the tidal arms in the Antennae and Superantennae galaxies. We describe observations of HI clouds with mass greater than 10(exp 8) solar mass in the interacting galaxy pair IC 2163/NGC 2207. This pair is important because we believe it represents an early stage in the formation of giant clouds during an encounter. We use a gravitational instability model to explain why the observed clouds are so massive and discuss a two-dimensional N-body simulation of an encounter that produces giant clouds
A possible radio supernova in the outer part of NGC 3310
As part of an on-going radio supernova monitoring program, we have discovered
a variable, compact steep spectrum radio source ~65 arcsec (~4 kpc) from the
centre of the starburst galaxy NGC 3310. If the source is at the distance of
NGC 3310, then its 5 GHz luminosity is ~3 x 10^{19} WHz^-1. The source
luminosity, together with its variability characteristics, compact structure
(<17 mas) and its association with a group of HII regions, leads us to propose
that it is a previously uncatalogued type II radio supernova. A search of
archival data also shows an associated X-ray source with a luminosity similar
to known radio supernova.Comment: 5 pages, 3 figures. Accepted by MNRA
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