7,644 research outputs found
Low-Altitude Reconnection Inflow-Outflow Observations during a 2010 November 3 Solar Eruption
For a solar flare occurring on 2010 November 3, we present observations using
several SDO/AIA extreme-ultraviolet (EUV) passbands of an erupting flux rope
followed by inflows sweeping into a current sheet region. The inflows are soon
followed by outflows appearing to originate from near the termination point of
the inflowing motion - an observation in line with standard magnetic
reconnection models. We measure average inflow plane-of-sky speeds to range
from ~150-690 km/s with the initial, high-temperature inflows being the
fastest. Using the inflow speeds and a range of Alfven speeds, we estimate the
Alfvenic Mach number which appears to decrease with time. We also provide
inflow and outflow times with respect to RHESSI count rates and find that the
fast, high-temperature inflows occur simultaneously with a peak in the RHESSI
thermal lightcurve. Five candidate inflow-outflow pairs are identified with no
more than a minute delay between detections. The inflow speeds of these pairs
are measured to be 10^2 km/s with outflow speeds ranging from 10^2-10^3 km/s -
indicating acceleration during the reconnection process. The fastest of these
outflows are in the form of apparently traveling density enhancements along the
legs of the loops rather than the loop apexes themselves. These flows could
either be accelerated plasma, shocks, or waves prompted by reconnection. The
measurements presented here show an order of magnitude difference between the
retraction speeds of the loops and the speed of the density enhancements within
the loops - presumably exiting the reconnection site.Comment: 31 pages, 13 figures, 1 table, Accepted to ApJ (expected publication
~July 2012
PUK5 EPOETIN ALFA AND DARBEPOETIN ALFA DOSING PATTERNS IN ANEMIC PRE-DIALYSIS CHRONIC KIDNEY DISEASE PATIENTS
Factors inhibiting local government engagement in environmental sustainability
The literature on local government management of the environment in Australia has been limited in that it has typically focused on the urban sphere. In contrast, this paper places rurality at the centre of its inquiry. It uses data from 15 case studies of rural local governments in Australia to identify the main factors that inhibit natural resource management by rural councils. These barriers mobilise around four key themes: capacity, commitment, co-ordination and community. While many of the issues raised in this study of non-urban shires have been described in previous research, the paper argues that the geographic location of the areas under investigation aggravates barriers to engaging sustainability initiatives. It is contended that rural local governments need to be resourced accordingly to ensure that natural resource management at the local government level in Australia is not compromised
Three new species of Pyricularia are isolated as Zingiberaceous endophytes from Thailand
A new taxon with Dyrithium-like characteristics was collected from Lake Fuxian in China. The taxon is typical of the Amphisphaeriaceae in that it has relatively large, ostiolate, immersed ascomata, unitunicate asci with a J+ subapical ring, and brown ascospores. It is similar to Dyrithium in that it has muriform ascospores, but considerable confusion surrounds this genus. In Dyrithium asci are bitunicate and lack a J+ subapical ring, while this was not true of our species. A new genus, Dyrithiopsis, therefore is established to accommodate this new taxon. Details of its anamorph also are provided, based on cultural studies. Parsimony analyses of part of the large-subunit rDNA provide further evidence to support the familial placement of this new genus in the Amphisphaeriaceae. The taxonomic position of Dyrithium also is discussed.published_or_final_versio
Severe Lumbar Disability Is Associated With Decreased Psoas Cross-Sectional Area in Degenerative Spondylolisthesis
Study Design: Retrospective cohort. Objectives: Alterations in lumbar paraspinal muscle cross-sectional area (CSA) may correlate with lumbar pathology. The purpose of this study was to compare paraspinal CSA in patients with degenerative spondylolisthesis and severe lumbar disability to those with mild or moderate lumbar disability, as determined by the Oswestry Disability Index (ODI). Methods: We retrospectively reviewed the medical records of 101 patients undergoing lumbar fusion for degenerative spondylolisthesis. Patients were divided into ODI score ≤40 (mild/moderate disability, MMD) and ODI score \u3e40 (severe disability, SD) groups. The total CSA of the psoas and paraspinal muscles were measured on preoperative magnetic resonance imaging (MRI). Results: There were 37 patients in the SD group and 64 in the MMD group. Average age and body mass index were similar between groups. For the paraspinal muscles, we were unable to demonstrate any significant differences in total CSA between the groups. Psoas muscle CSA was significantly decreased in the SD group compared with the MMD group (1010.08 vs 1178.6 mm2, P =.041). Multivariate analysis found that psoas CSA in the upper quartile was significantly protective against severe disability (P =.013). Conclusions: We found that patients with severe lumbar disability had no significant differences in posterior lumbar paraspinal CSA when compared with those with mild/moderate disability. However, severely disabled patients had significantly decreased psoas CSA, and larger psoas CSA was strongly protective against severe disability, suggestive of a potential association with psoas atrophy and worsening severity of lumbar pathology. © The Author(s) 2018
PMS67 TWO YEAR MAINTENANCE INFLIXIMAB DOSING AND ADMINISTRATION PATTERNS IN PATIENTS WITH RHEUMATOID ARTHRITIS
Understanding soil erosion impacts in temperate agroecosystems:Bridging the gap between geomorphology and soil ecology using nematodes as a model organism
Soil is a key asset of natural capital, providing a myriad of goods and
ecosystem services that sustain life through regulating, supporting and
provisioning roles, delivered by chemical, physical and biological
processes. One of the greatest threats to soil is accelerated erosion, which
raises a natural process to unsustainable levels, and has downstream
consequences (e.g.~economic, environmental and social). Global
intensification of agroecosystems is a recognised major cause of soil
erosion which, in light of predicted population growth and increased demand
for food security, will continue or increase. Transport and redistribution
of biota by soil erosion has hitherto been ignored and thus is poorly
understood. With the move to sustainable intensification this is a key
knowledge gap that needs to be addressed. Here we highlight the
erosion-energy and effective-erosion-depth continuum in soils,
differentiating between different forms of soil erosion, and argue that
nematodes are an appropriate model taxa to investigate impacts of erosion on
soil biota across scales. We review the different known mechanisms of soil
erosion that impact on soil biota in general, and nematodes in particular,
and highlight the few detailed studies, primarily from tropical regions,
that have considered soil biota. Based on the limited literature and
using nematodes as a model organism we outline future research priorities to
initially address the important interrelationships between soil erosion
processes and soil biota
Ion-Acoustic Solitons in Bi-Ion Dusty Plasma
The propagation of ion-acoustic solitons in a warm dusty plasma containing
two ion species is investigated theoretically. Using an approach based on the
Korteveg-de-Vries equation, it is shown that the critical value of the negative
ion density that separates the domains of existence of compressi- on and
rarefaction solitons depends continuously on the dust density. A modified
Korteveg-de Vries equation for the critical density is derived in the higher
order of the expansion in the small parameter. It is found that the nonlinear
coefficient of this equation is positive for any values of the dust density and
the masses of positive and negative ions. For the case where the negative ion
density is close to its critical value, a soliton solution is found that takes
into account both the quadratic and cubic nonlinearities. The propagation of a
solitary wave of arbitrary amplitude is investigated by the quasi-potential
method. It is shown that the range of the dust densities around the critical
value within which solitary waves with positive and negative potentials can
exist simultaneously is relatively wide.Comment: 17 pages, 5 figure
Advanced Placement Course-Taking and ACT Test Outcomes in Arkansas
Since 2008, Arkansas has sought to dramatically increase the number of students participating in Advanced Placement (AP) classes. This program, which allows students to access college -level content while still enrolled in high school, has been linked to higher student achievement and attainment. This brief shares recent research from the Office for Education Policy investigating whether students who take AP courses demonstrate better college readiness and examines how these trends vary for different demographic and socioeconomic groups in the state
Does the Timing of Money Matter? A Case Study of the Arkansas Academic Challenge Scholarship
In 2008, legislation passed to dramatically increase a small merit-aid program—the Arkansas Academic Challenge Scholarship (ACS) using newly created funds from the Arkansas Lottery. The expansion of this program created three unique groups of students eligible for funding: Prior Recipients, Traditional Recipients, and Current Achievers. Recent research from the Department of Education Reform at the University of Arkansas investigates how the scholarship influenced student outcomes for Current Achievers, who were already enrolled in college at the time the money was distributed. The study also investigates whether GPA, credit accumulation, and graduation rates vary depending on which year of college students were in when they received funding
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