5,008 research outputs found
Thermodynamics of Heat Shock Response
Production of heat shock proteins are induced when a living cell is exposed
to a rise in temperature. The heat shock response of protein DnaK synthesis in
E.coli for temperature shifts from temperature T to T plus 7 degrees,
respectively to T minus 7 degrees is measured as function of the initial
temperature T. We observe a reversed heat shock at low T. The magnitude of the
shock increases when one increase the distance to the temperature , thereby mimicking the non monotous stability of proteins at low
temperature. Further we found that the variation of the heat shock with T
quantitatively follows the thermodynamic stability of proteins with
temperature. This suggest that stability related to hot as well as cold
unfolding of proteins is directly implemented in the biological control of
protein folding. We demonstrate that such an implementation is possible in a
minimalistic chemical network.Comment: To be published in Physical Review Letter
A systematic review of cost-effectiveness analyses of complex wound interventions reveals optimal treatments for specific wound types.
BackgroundComplex wounds present a substantial economic burden on healthcare systems, costing billions of dollars annually in North America alone. The prevalence of complex wounds is a significant patient and societal healthcare concern and cost-effective wound care management remains unclear. This article summarizes the cost-effectiveness of interventions for complex wound care through a systematic review of the evidence base.MethodsWe searched multiple databases (MEDLINE, EMBASE, Cochrane Library) for cost-effectiveness studies that examined adults treated for complex wounds. Two reviewers independently screened the literature, abstracted data from full-text articles, and assessed methodological quality using the Drummond 10-item methodological quality tool. Incremental cost-effectiveness ratios were reported, or, if not reported, calculated and converted to United States Dollars for the year 2013.ResultsOverall, 59 cost-effectiveness analyses were included; 71% (42 out of 59) of the included studies scored 8 or more points on the Drummond 10-item checklist tool. Based on these, 22 interventions were found to be more effective and less costly (i.e., dominant) compared to the study comparators: 9 for diabetic ulcers, 8 for venous ulcers, 3 for pressure ulcers, 1 for mixed venous and venous/arterial ulcers, and 1 for mixed complex wound types.ConclusionsOur results can be used by decision-makers in maximizing the deployment of clinically effective and resource efficient wound care interventions. Our analysis also highlights specific treatments that are not cost-effective, thereby indicating areas of resource savings. Please see related article: http://dx.doi.org/10.1186/s12916-015-0288-5
On the Formation Height of the SDO/HMI Fe 6173 Doppler Signal
The Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics
Observatory (SDO) is designed to study oscillations and the mag- netic field in
the solar photosphere. It observes the full solar disk in the Fe I absorption
line at 6173\AA . We use the output of a high-resolution 3D, time- dependent,
radiation-hydrodynamic simulation based on the CO5BOLD code to calculate
profiles F({\lambda},x,y,t) for the Fe I 6173{\AA} line. The emerging profiles
F({\lambda},x,y,t) are multiplied by a representative set of HMI filter
transmission profiles R_i({\lambda},1 \leq i \leq 6) and filtergrams
I_i(x,y,t;1 \leq i \leq 6) are constructed for six wavelengths. Doppler
velocities V_HMI(x,y,t) are determined from these filtergrams using a
simplified version of the HMI pipeline. The Doppler velocities are correlated
with the original velocities in the simulated atmosphere. The cross-
correlation peaks near 100 km, suggesting that the HMI Doppler velocity signal
is formed rather low in the solar atmosphere. The same analysis is performed
for the SOHO/MDI Ni I line at 6768\AA . The MDI Doppler signal is formed
slightly higher at around 125 km. Taking into account the limited spatial
resolution of the instruments, the apparent formation height of both the HMI
and MDI Doppler signal increases by 40 to 50 km. We also study how
uncertainties in the HMI filter-transmission profiles affect the calculated
velocities.Comment: 15 pages, 11 Figure
Comparison of High-degree Solar Acoustic Frequencies and Asymmetry between Velocity and Intensity Data
Using the local helioseismic technique of ring diagram we analyze the
frequencies of high--degree f- and p-modes derived from both velocity and
continuum intensity data observed by MDI. Fitting the spectra with asymmetric
peak profiles, we find that the asymmetry associated with velocity line
profiles is negative for all frequency ranges agreeing with previous
observations while the asymmetry of the intensity profiles shows a complex and
frequency dependent behavior. We also observe systematic frequency differences
between intensity and velocity spectra at the high end of the frequency range,
mostly above 4 mHz. We infer that this difference arises from the fitting of
the intensity rather than the velocity spectra. We also show that the frequency
differences between intensity and velocity do not vary significantly from the
disk center to the limb when the spectra are fitted with the asymmetric profile
and conclude that only a part of the background is correlated with the
intensity oscillations.Comment: Accepted for publication in Astrophysical Journa
Radiocarbon dating the late upper paleolithic of Cantabrian Spain: El Mirón Cave Date List IV
Crohn's Disease and Urinary Bladder Mass
The presence of a bladder mass in a patient with inflammatory bowel disease poses a diagnostic
dilemma. We present the case of a 26-year-old male with a bladder mass who had not previously
been diagnosed with Crohn's disease. Initial biopsies of the bladder mass were consistent with inflammatory
changes, but superficial transitional cell carcinoma could not be reliably excluded.
Subsequent evaluation confirmed the presence of Crohn's disease with bladder involvement, and the
patient underwent bowel resection and partial cystectomy. Pathologic evaluation demonstrated
Crohn’s disease and no evidence of malignancy. Accurate differentiation of benign and malignant
bladder masses in patients with inflammatory bowel disease may be difficult and requires cooperation
between pathologists and clinicians
Benchmarking Fast-to-Alfv\'en Mode Conversion in a Cold MHD Plasma. II. How to get Alfv\'en waves through the Solar Transition Region
Alfv\'en waves may be difficult to excite at the photosphere due to low
ionization fraction and suffer near-total reflection at the transition region
(TR). Yet they are ubiquitous in the corona and heliosphere. To overcome these
difficulties, we show that they may instead be generated high in the
chromosphere by conversion from reflecting fast magnetohydrodynamic waves, and
that Alfv\'enic transition region reflection is greatly reduced if the fast
reflection point is within a few scale heights of the TR. The influence of mode
conversion on the phase of the reflected fast wave is also explored. This phase
can potentially be misinterpreted as a travel speed perturbation, with
implications for the practical seismic probing of active regions.Comment: 13 pages, 10 figures, accepted by ApJ 17 March 201
Differentiating patterns of violence in the family
The feasibility and prevalence of Reciprocal, Hierarchical and Paternal patterns of family aggression hypothesised by Dixon and Browne (2003) were explored within a sample of maltreating families. The psychological reports of 67 families referred to services for alleged child maltreatment that evidenced concurrent physical intimate partner violence and child maltreatment were investigated. Of these, 29 (43.3%) cases were characterised by hierarchical; 28 (41.8%) Reciprocal and 10 (14.9%) Paternal patterns. Significant differences in the form of child maltreatment perpetrated by mothers and fathers and parent dyads living in different patterns were found. In Hierarchical sub-patterns, fathers were significantly more likely to have been convicted for a violent and/or sexual offence than mothers and were significantly less likely to be biologically related to the child. The findings demonstrate the existence of the different patterns in a sample of families involved in the Child Care Protection process in England and Wales, supporting the utility of a holistic approach to understanding aggression in the family
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