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Renal Infarct After Endovascular Abdominal Aortic Aneurysm Repair: Consider in Back Pain Differential
As hypertension, obesity, and hyperlipidemia become more widespread, the prevalence of abdominal aortic aneurysms (AAA) has also increased.1 Traditionally those with multiple comorbidities – also those with greatest AAA mortality – were considered too high risk for operative repair. In recent decades, however, endovascular abdominal aortic aneurysm repair (EVAR) has become a popular option, especially for high-risk patients. Overall, short-term outcomes are comparable to traditional open repair despite higher patient baseline risk. However, EVAR comes with its own risks, which the emergency physician should be aware of. Here, we present a rare complication of EVAR: device thrombosis with subsequent renal infarct
Vagrancy, Vice, and Victimhood: The Evolution of Homeless Persecution
Through the examination of how urban space is constructed, one can see how the city testifies to the ways that history and memory come to shape human experience and the vocabularies with which it is understood and remembered. This paper will diverge from contemporary discussions of history and memory through an investigation of the roles of affect and social location have in shaping how the city is thought of and remembered differently. It will compare historical constructions of city folk in an attempt to understand the role of hegemonic social, economic, and political conditions in the construction of “history.” This paper draws on the work of affective communication theory, and analyzes how memory is impacted by homeless erasure through the lenses of discourse, spatiality, and performance. This paper will conclude by using Jacques Derrida’s conception of hauntology to prove that affect comes to inform all parts of the memory-making process, and argue that remaining attune to the keenly-felt absences of historical memories often bequeaths entirely new counter-histories of their own
The staphylococcal QacR multidrug regulator binds a correctly spaced operator as a pair of dimers
Expression of the Staphylococcus aureus plasmid-encoded QacA multidrug transporter is regulated by the
divergently encoded QacR repressor protein. To circumvent the formation of disulfide-bonded degradation
products, site-directed mutagenesis to replace the two cysteine residues in wild-type QacR was undertaken.
Analysis of a resultant cysteineless QacR derivative indicated that it retained full DNA-binding activities in
vivo and in vitro and continued to be fully proficient for the mediation of induction of qacA expression in
response to a range of structurally dissimilar multidrug transporter substrates. The cysteineless QacR protein
was used in cross-linking and dynamic light-scattering experiments to show that its native form was a dimer,
whereas gel filtration indicated that four QacR molecules bound per DNA operator site. The addition of
inducing compounds led to the dissociation of the four operator-bound QacR molecules from the DNA as
dimers. Binding of QacR dimers to DNA was found to be dependent on the correct spacing of the operator
half-sites. A revised model proposed for the regulation of qacA expression by QacR features the unusual
characteristic of one dimer of the regulatory protein binding to each operator half-site by a process that does
not appear to require the prior self-assembly of QacR into tetramers
Chiral Extrapolation: An Analogy with Effective Field Theory
We draw an analogy between the chiral extrapolation of lattice QCD
calculations from large to small quark masses and the interpolation between the
large mass (weak field) and small mass (strong field) limits of the
Euler--Heisenberg QED effective action. In the latter case, where the exact
answer is known, a simple extrapolation of a form analogous to those proposed
for the QCD applications is shown to be surprisingly accurate over the entire
parameter range.Comment: 6 pp, revtex, 3 figs; minor changes -- version to appear in PL
Meningococcal disease in children in Merseyside, England:a 31 year descriptive study
Meningococcal disease (MCD) is the leading infectious cause of death in early childhood in the United Kingdom, making it a public health priority. MCD most commonly presents as meningococcal meningitis (MM), septicaemia (MS), or as a combination of the two syndromes (MM/MS). We describe the changing epidemiology and clinical presentation of MCD, and explore associations with socioeconomic status and other risk factors. A hospital-based study of children admitted to a tertiary children's centre, Alder Hey Children's Foundation Trust, with MCD, was undertaken between 1977 to 2007 (n = 1157). Demographics, clinical presentations, microbiological confirmation and measures of deprivation were described. The majority of cases occurred in the 1-4 year age group and there was a dramatic fall in serogroup C cases observed with the introduction of the meningococcal C conjugate (MCC) vaccine. The proportion of MS cases increased over the study period, from 11% in the first quarter to 35% in the final quarter. Presentation with MS (compared to MM) and serogroup C disease (compared to serogroup B) were demonstrated to be independent risk factors for mortality, with odds ratios of 3.5 (95% CI 1.18 to 10.08) and 2.18 (95% CI 1.26 to 3.80) respectively. Cases admitted to Alder Hey were from a relatively more deprived population (mean Townsend score 1.25, 95% CI 1.09 to 1.41) than the Merseyside reference population. Our findings represent one of the largest single-centre studies of MCD. The presentation of MS is confirmed to be a risk factor of mortality from MCD. Our study supports the association between social deprivation and MCD
Chiral Extrapolations and Exotic Meson Spectrum
We examine the chiral corrections to exotic meson masses calculated in
lattice QCD. In particular, we ask whether the non-linear chiral behavior at
small quark masses, which has been found in other hadronic systems, could lead
to large corrections to the predictions of exotic meson masses based on linear
extrapolations to the chiral limit. We find that our present understanding of
exotic meson decay dynamics suggests that open channels may not make a
significant contribution to such non-linearities whereas the virtual, closed
channels may be important.Comment: 13 pagers, 2 figure
Plant exudates may stabilize or weaken soil depending on species, origin and time
We hypothesized that plant exudates could either gel or disperse soil depending on their chemical characteristics. Barley (Hordeum vulgare L. cv. Optic) and maize (Zea mays L.cv. Freya) root exudates were collected using an aerated hydroponic method and compared to chia (Salvia hispanica L.) seed exudate, a commonly used root exudate analogue. Sandy loam soil passed through a 500-μm mesh was treated with each exudate at a concentrationof 4.6 mg exudate g-1 dry soil. Two sets of soil samples were prepared, One set of treated soil samples was maintained at 4oC to suppress microbial processes. To characterize the effect of decomposition, the second set of samples was incubated at 16C for 2 weeks at – 30 kPa matric potential. Gas chromatography–mass spectrometry (GC–MS) analysis of the exudates found that barley had the largest organic acid content and chia the largest content of sugars (polysaccharide-derived or free), and maize was in between barley and chia. Yield stress of amended soil samples was measured by an oscillatory strain sweep test with a cone plate rheometer. When microbial decomposition was suppressed at 4oC, yield stress increased 20-fold for chia seed exudate and two-fold for maize root exudate compared to the control, whereas for barley root exudate it decreased to half. The yield stress after 2 weeks of incubation compared to soil with suppressed microbial decomposition increased by 85% for barley root exudate, but for chia and maize it decreased to by 87% and 54%, respectively. Barley root exudation might therefore disperse soil and this could facilitate nutrient release. The maize root and chia seed exudates gelled soil, which could create a more stable soil structure around roots or seeds
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