600 research outputs found
Catastrophic Fermi surface reconstruction in the shape-memory alloy AuZn
AuZn undergoes a shape-memory transition at 67 K. The de Haas van Alphen
effect persists to 100 K enabling the observation of a change in the quantum
oscillation spectrum indicative of a catastrophic Fermi surface reconstruction
at the transition. Coexistence of both Fermi surfaces at low temperatures is
suggestive of an intrinsic phase separation in the bulk of the material. In
addition, a Dingle analysis reveals a sharp change in the scattering mechanism
at a threshold cyclotron radius, which we suggest to be related to the
underlying microstructure that drives the shape-memory effect.Comment: 4 pages, 4 figure
Fermi Surface as a Driver for the Shape-Memory Effect in AuZn
Martensites are materials that undergo diffusionless, solid-state
transitions. The martensitic transition yields properties that depend on the
history of the material and may allow it to recover its previous shape after
plastic deformation. This is known as the shape-memory effect (SME). We have
succeeded in identifying the primary electronic mechanism responsible for the
martensitic transition in the shape-memory alloy AuZn by using Fermi-surface
measurements (de Haas-van Alphen oscillations) and band-structure calculations.
This strongly suggests that electronic band structure is an important
consideration in the design of future SME alloys
Recommended from our members
Serum Concentrations of Organochlorine Pesticides and Growth among Russian Boys
Background: Limited human data suggest an association of organochlorine pesticides (OCPs) with adverse effects on children’s growth
The Moral Resilience of Young People Who Care
This paper draws on findings from a qualitative study of the social wellbeing of young people caring for a close family member. The research makes a novel contribution to the international literature by examining the moral resilience of young adult carers. Focus groups or individual, semi-structured interviews were undertaken with fifteen young people in South-East England during 2018–2019. The paper explores whether young people with a seriously ill or disabled family member define and conduct themselves in moral terms and how they respond to the moral challenges of a caring life. It was found that the participants saw moral value in their caring role and their actions reflected a desire to provide compassionate care. Previous research into young adult carers had indicated that the caring role stimulated their political consciousness, but this study suggests that the role also strengthens their moral consciousness. However, designating girls as carers in early life shifts the moral responsibility to females and compounds gender inequity in caring. Hence, there is a need to address social and gender inequalities in care. In addition, healthcare professionals should recognise when statutory input is necessary to facilitate young people’s broader lifeplans
MicroRNA132 Modulates Short-Term Synaptic Plasticity but Not Basal Release Probability in Hippocampal Neurons
MicroRNAs play important regulatory roles in a broad range of cellular processes including neuronal morphology and long-term synaptic plasticity. MicroRNA-132 (miR132) is a CREB-regulated miRNA that is induced by neuronal activity and neurotrophins, and plays a role in regulating neuronal morphology and cellular excitability. Little is known about the effects of miR132 expression on synaptic function. Here we show that overexpression of miR132 increases the paired-pulse ratio and decreases synaptic depression in cultured mouse hippocampal neurons without affecting the initial probability of neurotransmitter release, the calcium sensitivity of release, the amplitude of excitatory postsynaptic currents or the size of the readily releasable pool of synaptic vesicles. These findings are the first to demonstrate that microRNAs can regulate short-term plasticity in neurons
- …