1,124 research outputs found

    AhR, inflammation and breast cancer

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    Aryl hydrocarbon receptor (AhR), an evolutionary conserved transcription factor, is a pleiotropic signal transductor. Thanks to its promiscuous ligand binding domain, during the evolution of eukaryotic cells its developmental functions were integrated with biosensor functions. Its activation by a multitude of endogenous and exogenous molecules stimulates its participation in several pathways, some of which are linked to inflammation and breast cancer (BC). Over time, the study of this malignancy has led to the identification of several therapeutic targets in cancer cells. An intense area of study is dedicated to BC phenotypes lacking adequate targets. In this context, due to its high constitutive activation in BC, AhR is currently gaining more and more attention

    Hyperaccurate thermoelectric currents

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    Thermodynamic currents, such as energy, heat, and entropy production, can fluctuate significantly at the nanoscale. However, some fluctuate less than others. Hyperaccurate currents are defined as those which fluctuate the least, in the sense that they maximize the signal-to-noise ratio (precision). In this Letter we analytically determine what are the hyperaccurate currents in quantum thermoelectrics, modeled by coherent transport in the Landauer-Büttiker formalism. Our results yield a tight and general bound on precision, which replace the classical thermodynamic uncertainty relations, that can be violated in quantum thermoelectrics. They also allow us to address the question of how close to hyperaccurate is a given current. We illustrate our findings for smooth boxcar functions, and for a double quantum dot operating as a thermal machine. In the latter, we use our results to establish the parameter ranges for which the output power of an autonomous engine can become hyperaccurate arbitrarily far from equilibrium

    Thermodynamics of precision in quantum nanomachines

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    Fluctuations strongly affect the dynamics and functionality of nanoscale thermal machines. Recent developments in stochastic thermodynamics have shown that fluctuations in many far-from-equilibrium systems are constrained by the rate of entropy production via so-called thermodynamic uncertainty relations. These relations imply that increasing the reliability or precision of an engine's power output comes at a greater thermodynamic cost. Here we study the thermodynamics of precision for small thermal machines in the quantum regime. In particular, we derive exact relations between the power, power fluctuations, and entropy production rate for several models of few-qubit engines (both autonomous and cyclic) that perform work on a quantized load. Depending on the context, we find that quantum coherence can either help or hinder where power fluctuations are concerned. We discuss design principles for reducing such fluctuations in quantum nanomachines and propose an autonomous three-qubit engine whose power output for a given entropy production is more reliable than would be allowed by any classical Markovian model

    On The Distribution Of Siphonops Paulensis Boettger, 1892 (gymnophiona: Siphonopidae): Four New Brazilian State Records

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    Siphonops paulensis Boettger, 1892 is a Neotropical siphonopid caecilian widely distributed in South America. Herein, we fill knowledge gaps in the distribution of S. paulensis mostly in northeastern Brazil, including four new state records. © 2016 Check List and Authors.12
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