Malliavin calculus for fractional heat equation

In this article, we give some existence and smoothness results for the law of the solution to a stochastic heat equation driven by a finite dimensional fractional Brownian motion with Hurst parameter $H>1/2$. Our results rely on recent tools of Young integration for convolutional integrals combined with stochastic analysis methods for the study of laws of random variables defined on a Wiener space.Comment: Dedicated to David Nualart on occasion of his 60th birthda

Postsynaptic Signals Mediating Induction of Long-Term Synaptic Depression in the Entorhinal Cortex

The entorhinal cortex receives a large projection from the piriform cortex, and synaptic plasticity in this pathway may affect olfactory processing. In vitro whole cell recordings have been used here to investigate postsynaptic signalling mechanisms that mediate the induction of long-term synaptic depression (LTD) in layer II entorhinal cortex cells. To induce LTD, pairs of pulses, using a 30-millisecond interval, were delivered at 1 Hz for 15 minutes. Induction of LTD was blocked by the NMDA receptor antagonist APV and by the calcium chelator BAPTA, consistent with a requirement for calcium influx via NMDA receptors. Induction of LTD was blocked when the FK506 was included in the intracellular solution to block the phosphatase calcineurin. Okadaic acid, which blocks activation of protein phosphatases 1 and 2a, also prevented LTD. Activation of protein phosphatases following calcium influx therefore contributes to induction of LTD in layer II of the entorhinal cortex

Does the predicate ‘is true’ specify a genuine property of assertions?

Theorists are divided as to whether truth is or is not a substantive property. In a nutshell, those that maintain that it is, pragmatists, coherentists, and correspondence theorists among others, oppose deflationists who claim that ascribing truth to an assertion is nothing more, or little more, than simply making the assertion. Deflationists typically refuse to grant truth a metaphysical standing, although we must recognise deflationism is not just a statement about the metaphysical status of truth. Unfortunately, propertihood is elusive to define in relation to truth, but to deny it is to say that truth is not a quality bestowed on truth-bearers, one that they possess;1 or to say that truth is not the kind of philosophical entity apt for dissection into constituents and common to all true assertions; or to say that truth ascription is a mere convenience, a façon de parler that eases conversation and confers style; or to say that truth is in some sense a trivial logical fragment that all but disappears upon closer inspection. Intuitions and theories vary on the details of what it takes to be a property, but some or all of these premises are accepted in embracing deflationism. Whiteness, for example, is an uncontroversial property of snow, even if it is arguably a relational one; what deflationism rejects is the analogous property of truth-bearers

Magnon diffusion lengths in bulk and thin film Fe3O4 for spin Seebeck applications

The magnon diffusion length (MDL) is understood to play a major role in the thickness dependence of spin Seebeck effect (SSE) voltages in Fe3O4/Pt thin films. Here we extract the MDL in an Fe3O4 single crystal using inelastic neutron scattering (INS) and in Fe3O4/Pt thin films using accurate heat flux SSE and static magnetization measurements. The INS MDLs were 34 ± 8 nm at 300 K and 27 ± 6 nm at 50 K. The SSE MDLs decreased with temperature (19 ± 2 nm at 300 K and 13 ± 4 nm at 50 K), but were markedly smaller. Whilst the bulk MDL is expected to be an upper limit of the MDL in thin films, we show that the film magnetization must be considered to obtain MDLs from SSE measurements. This study highlights the importance of disentangling the role of various effects in SSE measurements which is crucial in increasing the efficiencies of thermomagnetic energy harvesting devices