3,953 research outputs found
Central oxytocin and food intake: focus on macronutrient-driven reward
Centrally acting oxytocin (OT) is known to terminate food consumption in response to excessive stomach distension, increase in salt loading, and presence of toxins. Hypothalamic-hindbrain OT pathways facilitate these aspects of OT-induced hypophagia. However, recent discoveries have implicated OT in modifications of feeding via reward circuits: OT has been found to differentially affect consumption of individual macronutrients in choice and no-choice paradigms. In this mini-review, we focus on presenting and interpreting evidence that defines OT as a key component of mechanisms that reduce eating for pleasure and shape macronutrient preferences. We also provide remarks on challenges in integrating the knowledge on physiological and pathophysiological states in which both OT activity and macronutrient preferences are affected
Efficient bounds on quantum communication rates via their reduced variants
We investigate one-way communication scenarios where Bob manipulating on his
parts can transfer some sub-system to the environment. We define reduced
versions of quantum communication rates and further, prove new upper bounds on
one-way quantum secret key, distillable entanglement and quantum channel
capacity by means of their reduced versions. It is shown that in some cases
they drastically improve their estimation.Comment: 6 pages, RevTe
Generic emergence of classical features in quantum Darwinism
Quantum Darwinism explains the emergence of classical reality from the
underlying quantum reality by the fact that a quantum system is observed
indirectly, by looking at parts of its environment, so that only specific
information about the system that is redundantly proliferated to many parts of
the environment becomes accessible and objective. However it is not clear under
what conditions this mechanism holds true. Here we rigorously prove that the
emergence of classicality is a general feature of any quantum dynamics:
observers who acquire information about a quantum system indirectly have access
at most to classical information about one and the same measurement of the
quantum system; moreover, if such information is available to many observers,
they necessarily agree. Remarkably, our analysis goes beyond the
system-environment categorization. We also provide a full characterization of
the so-called quantum discord in terms of local redistribution of correlations.Comment: Closer to published versio
Mesoscopic Fluctuations of the Pairing Gap
A description of mesoscopic fluctuations of the pairing gap in finite-sized
quantum systems based on periodic orbit theory is presented. The size of the
fluctuations are found to depend on quite general properties. We distinguish
between systems where corresponding classical motion is regular or chaotic, and
describe in detail fluctuations of the BCS gap as a function of the size of the
system. The theory is applied to different mesoscopic systems: atomic nuclei,
metallic grains, and ultracold fermionic gases. We also present a detailed
description of pairing gap variation with particle number for nuclei based on a
deformed cavity potential.Comment: Conference Proceeding of Mesoscopic Workshop WNMP0
Quasi-deterministic transport of Brownian particles in an oscillating periodic potential
We consider overdamped Brownian dynamics in a periodic potential with
temporally oscillating amplitude. We analyze the transport which shows
effective diffusion enhanced by the oscillations and derive approximate
expressions for the diffusion coefficient. Furthermore we analyze the effect of
the oscillating potential on the transport if additionally a constant force is
applied. We show the existence of synchronization regimes at which the
deterministic dynamics is in resonance with the potential oscillations giving
rise to transport with extremely low dispersion. We distinguish slow and fast
oscillatory driving and give analytical expressions for the mean velocity and
effective diffusion.Comment: submitted: Feb 12th, 201
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