1,445 research outputs found
Antiferromagnetic and Orbital Ordering on a Diamond Lattice Near Quantum Criticality
We present neutron scattering measurements on powder samples of the spinel
FeSc2S4 that reveal a previously unobserved magnetic ordering transition
occurring at 11.8(2)~K. Magnetic ordering occurs subsequent to a subtle
cubic-to-tetragonal structural transition which distorts Fe coordinating sulfur
tetrahedra lifting the orbital degeneracy. The application of 1~GPa hydrostatic
pressure appears to destabilize this N\'eel state, reducing the transition
temperature to 8.6(8)~K and redistributing magnetic spectral weight to higher
energies. The relative magnitudes of ordered
and fluctuating moments show that the
magnetically ordered ground state of FeSc2S4 is drastically renormalized and in
proximity to criticality.Comment: 16 pages, 12 figure
Failure of systemic ketosis to control cachexia and the growth rate of the Walker 256 carcinosarcoma in rats.
The Walker 256 carcinosarcoma was shown to lack the enzyme 3-ketoacid CoA transferase. This suggests that ketone bodies cannot be used as a major substrate for the energy metabolism of this tumour. Systemic ketosis (1-2 mM acetoacetate plus 3-hydroxybutyrate) was induced both in tumour-bearing and in non-tumour-bearing rats with a diet containing 70% medium chain triglyceride. However, in rats bearing the Walker 256 tumour, this dietary ketosis did not reduce the tumour growth rate nor did it prevent the subsequent decrease in host body weight. Host body nitrogen losses were similarly unaffected. The ketosis induced in tumour bearing rats was shown to be abnormal since the blood glucose concentration of ketotic, tumour-bearing rats was significantly higher compared with that of ketotic non-tumour bearing rats (5.2 +/- 0.4 mM cf 3.4 +/- 0.6 mM, P less than 0.01). These results may partly explain why systemic ketosis failed to alter the growth and cachexia induced by the Walker 256 carcinosarcoma
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Using the delphi approach to identify priority areas for health visiting practice in an area of deprivation
Families with children living in areas of high deprivation face multiple health and social challenges, and this high level of need has impacts on the work of health practitioners working in such areas. All families in the UK with children under five years have access to health visiting services, and health visitors have a key role in mitigating the effects of deprivation by addressing health needs through evidence based practice. This paper reports the first stage of a project in Tower Hamlets, London, an area of significant deprivation, which aims to develop an evidence-based toolkit to support health visitors in their practice with families. The first stage used a modified Delphi process to identify the priority health needs of families in the area between June and July 2012. The three-stage Delphi process involved 25 people: four health visitors, four other members of the health visiting service, and 17 representatives of other services working with families. A focus group event was followed by a second event where individuals completed a questionnaire ranking the 27 priorities identified in the first event. The consultation process concluded with participants completing a second questionnaire, by email, confirming or changing their prioritisation of the topics
Single spin-polarised Fermi surface in SrTiO thin films
The 2D electron gas (2DEG) formed at the surface of SrTiO(001) has
attracted great interest because of its fascinating physical properties and
potential as a novel electronic platform, but up to now has eluded a
comprehensible way to tune its properties. Using angle-resolved photoemission
spectroscopy with and without spin detection we here show that the band filling
can be controlled by growing thin SrTiO films on Nb doped SrTiO(001)
substrates. This results in a single spin-polarised 2D Fermi surface, which
bears potential as platform for Majorana physics. Based on our results it can
furthermore be concluded that the 2DEG does not extend more than 2 unit cells
into the film and that its properties depend on the amount of SrO at the
surface and possibly the dielectric response of the system
Evolution from a nodeless gap to d(x2-y2) form in underdoped La(2-x)SrxCuO4
Using angle-resolved photoemission (ARPES), it is revealed that the
low-energy electronic excitation spectra of highly underdoped superconducting
and non-superconducting La(2-x)SrxCuO4 cuprates are gapped along the entire
underlying Fermi surface at low temperatures. We show how the gap function
evolves to a d(x2-y2) form as increasing temperature or doping, consistent with
the vast majority of ARPES studies of cuprates. Our results provide essential
information for uncovering the symmetry of the order parameter(s) in strongly
underdoped cuprates, which is a prerequisite for understanding the pairing
mechanism and how superconductivity emerges from a Mott insulator.Comment: 5 pages, 4 figure
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