In this work, we introduce two models of Feynman's ratchet and pawl system. Molecular dynamics is carried out to simulate the two designs for Feynman's ratchet and pawl systems followed by a Langevin dynamics simulation of the reduced system. We find that the ratchet will rotate as designed when the temperature of the pawl chamber is lower than that of the ratchet chamber, which is consistent w...

We present a model for a thermal Brownian motor based on Feynman’s famous ratchet and pawl device. Its main feature is that the ratchet and the pawl are in different thermal baths and connected by an harmonic spring. We simulate its dynamics, explore its main features and also derive an approximate analytical solution for the mean velocity as a function of the external torque applied and the te...

this article generates the first persian academic word list (pawl) which comprises the most frequently used academic vocabulary in persian academic texts. the pawl was compiled from a corpus of 927,008 running words from academic resources. two principles of range and frequency of word families guided the selection and arrangement of the word list. the corpus included seven books and one hundre...

The present corpus-based lexical study reports the development of a Pharmacy Academic Word List (PAWL); a list of the most frequent words from a corpus of 3,458,445 tokens made up of 800 most recent pharmacy texts including research articles, review articles, and short communications in four sub-disciplines of pharmacy. WordSmith (Scott, 2017) and AntWordProfiler (Anthony, 2014) were used to sc...

We introduce a simple, discrete model of Feynman's ratchet and pawl, operating between two heat reservoirs. We solve exactly for the steady-state directed motion and heat flows produced, first in the absence and then in the presence of an external load. We show that the model can act both as a heat engine and as a refrigerator. We finally investigate the behavior of the system near equilibrium,...

We introduce a simple, discrete model of Feynman's ratchet and pawl, operating between two heat reservoirs. We solve exactly for the steady-state directed motion and heat flows produced, first in the absence and then in the presence of an external load. We show that the model can act both as a heat engine and as a refrigerator. We finally investigate the behavior of the system near equilibrium,...

Classical and quantum aspects of fluctuations are reviewed in a discussion on the universality of the second law. Consideration is given to the need of information and the requirement of a ratchet and pawl-type mechanism for the utilization of energy from fluctuations. Some aspects of the quantum theory of the Copenhagen school are compared to those of Bohm within the discussion.

The overall goal of this project was to identify the neural circuitry involved in paw withdrawal learning (PaWL) in complete spinal cord transected (ST) mice. Pseudorabies virus (PRV)-Bartha 152 was injected into the tibialis anterior (TA), the primary muscle involved in this learning. The use of PRV, a transsynaptic retrograde marker, allowed labeling of the TA motoneurons and its associated i...