143 research outputs found
An ongoing case-control study to evaluate the NHS Bowel Cancer Screening Programme
© 2014 Massat et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
Spin-echo and quantum versus classical critical fluctuations in TmVO
Using spin-echo Nuclear Magnetic Resonance in the model Transverse-Field
Ising system TmVO, we show that low frequency quantum fluctuations at the
quantum critical point have a very different effect on V nuclear-spins
than classical low-frequency noise or fluctuations that arise at a finite
temperature critical point. Spin-echos filter out the low frequency classical
noise but not the quantum fluctuations. This allows us to directly visualize
the quantum critical fan and demonstrate the persistence of quantum
fluctuations at the critical coupling strength in TmVO to high temperatures
in an experiment that remains transparent to finite temperature classical phase
transitions. These results show that while dynamical decoupling schemes can be
quite effective in eliminating classical noise in a qubit, a quantum critical
environment may lead to rapid entanglement and decoherence.Comment: 10 pages, 5 figure
Second order Zeeman interaction and ferroquadrupolar order in TmVO
TmVO exhibits ferroquadrupolar order of the Tm 4f electronic orbitals
at low temperatures, and is a model system for Ising nematicity that can be
tuned continuously to a quantum phase transition via magnetic fields along the
-axis. Here we present V nuclear magnetic resonance data in magnetic
fields perpendicular to the -axis in a single crystal that has been
carefully cut by a plasma focused ion beam to an ellipsoidal shape to minimize
the inhomogeneity of the internal demagnetization field. The resulting dramatic
increase in spectral resolution enabled us to resolve the anisotropy of the
electric field gradient and to measure the magnetic and quadrupolar relaxation
channels separately. Perpendicular magnetic fields nominally do not couple to
the low energy degrees of freedom, but we find a significant nonlinear
contribution for sufficiently large fields that give rise to a rich phase
diagram. The in-plane magnetic field can act either as an effective transverse
or longitudinal field to the Ising nematic order, depending on the orientation
relative to the principle axes of the quadrupole order, and leads to a marked
in-plane anisotropy in both relaxation channels. We find that the small
in-plane transverse fields initially enhance the ferroquadrupolar ordering
temperature but eventually suppress the long-range order. We tentatively
ascribe this behavior to the competing effects of field-induced mixing of
higher energy crystal field states and the destabilizing effects of
field-induced quantum fluctuations.Comment: 15 pages, 13 figure
Lattice-shifted nematic quantum critical point in
We report the evolution of nematic fluctuations in single crystals as a function of Sulfur content x across the nematic quantum critical point (QCP) ~ 0.17 via Raman scattering. The Raman spectra in the nematic channel consist of two components, but only the low energy one displays clear fingerprints of critical behavior and is attributed to itinerant carriers.
Curie–Weiss analysis of the associated nematic susceptibility indicates a substantial effect of nemato-elastic coupling, which shifts
the location of the nematic QCP. We argue that this lattice-induced shift likely explains the absence of any enhancement of the
superconducting transition temperature at the QCP. The presence of two components in the nematic fluctuations spectrum is
attributed to the dual aspect of electronic degrees of freedom in Hund’s metals, with both itinerant carriers and local moments
contributing to the nematic susceptibility
Lattice-Shifted Nematic Quantum Critical Point in FeSeS
We report the evolution of nematic fluctuations in FeSeS single
crystals as a function of Sulfur content across the nematic quantum
critical point (QCP) 0.17 via Raman scattering. The Raman spectra in
the nematic channel consist of two components, but only the low energy
one displays clear fingerprints of critical behavior and is attributed to
itinerant carriers. Curie-Weiss analysis of the associated nematic
susceptibility indicates a substantial effect of nemato-elastic coupling which
shifts the location of the nematic QCP. We argue that this lattice-induced
shift likely explains the absence of any enhancement of the superconducting
transition temperature at the QCP. The presence of two components in the
nematic fluctuations spectrum is attributed to the dual aspect of electronic
degrees of freedom in Hund's metals, with both itinerant carriers and local
moments contributing to the nematic susceptibility.Comment: 10 pages, 5 figure
Circulating adrenomedullin estimates survival and reversibility of organ failure in sepsis: the prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock-1 (AdrenOSS-1) study
Background: Adrenomedullin (ADM) regulates vascular tone and endothelial permeability during sepsis. Levels of circulating biologically active ADM (bio-ADM) show an inverse relationship with blood pressure and a direct relationship with vasopressor requirement. In the present prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock 1 (, AdrenOSS-1) study, we assessed relationships between circulating bio-ADM during the initial intensive care unit (ICU) stay and short-term outcome in order to eventually design a biomarker-guided randomized controlled trial. Methods: AdrenOSS-1 was a prospective observational multinational study. The primary outcome was 28-day mortality. Secondary outcomes included organ failure as defined by Sequential Organ Failure Assessment (SOFA) score, organ support with focus on vasopressor/inotropic use, and need for renal replacement therapy. AdrenOSS-1 included 583 patients admitted to the ICU with sepsis or septic shock. Results: Circulating bio-ADM levels were measured upon admission and at day 2. Median bio-ADM concentration upon admission was 80.5 pg/ml [IQR 41.5-148.1 pg/ml]. Initial SOFA score was 7 [IQR 5-10], and 28-day mortality was 22%. We found marked associations between bio-ADM upon admission and 28-day mortality (unadjusted standardized HR 2.3 [CI 1.9-2.9]; adjusted HR 1.6 [CI 1.1-2.5]) and between bio-ADM levels and SOFA score (p < 0.0001). Need of vasopressor/inotrope, renal replacement therapy, and positive fluid balance were more prevalent in patients with a bio-ADM > 70 pg/ml upon admission than in those with bio-ADM ≤ 70 pg/ml. In patients with bio-ADM > 70 pg/ml upon admission, decrease in bio-ADM below 70 pg/ml at day 2 was associated with recovery of organ function at day 7 and better 28-day outcome (9.5% mortality). By contrast, persistently elevated bio-ADM at day 2 was associated with prolonged organ dysfunction and high 28-day mortality (38.1% mortality, HR 4.9, 95% CI 2.5-9.8). Conclusions: AdrenOSS-1 shows that early levels and rapid changes in bio-ADM estimate short-term outcome in sepsis and septic shock. These data are the backbone of the design of the biomarker-guided AdrenOSS-2 trial. Trial registration: ClinicalTrials.gov, NCT02393781. Registered on March 19, 2015
Evaluation of a service intervention to improve awareness and uptake of bowel cancer screening in ethnically-diverse areas
The Policy
Research Unit in Cancer Awareness, Screening and Early Diagnosis
receives funding for a research programme from the UK
Department of Health Policy Research Programme (grant no.
106/0001). It is a collaboration between researchers from seven
institutions (the Queen Mary University of London, the UCL, the
King’s College London, the London School of Hygiene and
Tropical Medicine, the Hull York Medical School, the Durham
University and the Peninsula Medical School)
Modular hybrid total hip arthroplasty. Experimental study in dogs
Background: This prospective experimental study evaluated the surgical procedure and results of modular hybrid total hip arthroplasty in dogs.Methods: Ten skeletally mature healthy mongrel dogs with weights varying between 19 and 27 kg were used. Cemented modular femoral stems and uncemented porous-coated acetabular cups were employed. Clinical and radiographic evaluations were performed before surgery and at 30, 60, 90, 120, 180 and 360 days post-operation.Results: Excellent weight bearing was noticed in the operated limb in seven dogs. Dislocation followed by loosening of the prosthesis was noticed in two dogs, which were therefore properly treated with a femoral head osteotomy. Femoral fracture occurred in one dog, which was promptly treated with full implant removal and femoral osteosynthesis.Conclusions: The canine modular hybrid total hip arthroplasty provided excellent functionality of the operated limb
Quantitative trait locus analysis identifies Gabra3 as a regulator of behavioral despair in mice
The Tail Suspension Test (TST), which measures behavioral despair, is widely used as an animal model of human depressive disorders and antidepressant efficacy. In order to identify novel genes involved in the regulation of TST performance, we crossed an inbred strain exhibiting low immobility in the TST (RIIIS/J) with two high-immobility strains (C57BL/6J and NZB/BlNJ) to create two distinct F2 hybrid populations. All F2 offspring (n = 655) were genotyped at high density with a panel of SNP markers. Whole-genome interval mapping of the F2 populations identified statistically significant quantitative trait loci (QTLs) on mouse chromosomes (MMU) 4, 6, and X. Microarray analysis of hippocampal gene expression in the three parental strains was used to identify potential candidate genes within the MMUX QTLs identified in the NZB/BlNJ × RIIIS/J cross. Expression of Gabra3, which encodes the GABAA receptor α3 subunit, was robust in the hippocampus of B6 and RIIIS mice but absent from NZB hippocampal tissue. To verify the role of Gabra3 in regulating TST behavior in vivo, mice were treated with SB-205384, a positive modulator of the α3 subunit. SB-205384 significantly reduced TST immobility in B6 mice without affecting general activity, but it had no effect on behavior in NZB mice. This work suggests that GABRA3 regulates a behavioral endophenotype of depression and establishes this gene as a viable new target for the study and treatment of human depression
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