scholarly journals Biophotons and Emergence of Quantum Coherence—A Diffusion Entropy Analysis

Entropy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. 554
Author(s):  
Maurizio Benfatto ◽  
Elisabetta Pace ◽  
Catalina Curceanu ◽  
Alessandro Scordo ◽  
Alberto Clozza ◽  
...  
Keyword(s):  
Correlation Function ◽  
Quantum Coherence ◽  
Photon Emission ◽  
Entropy Analysis ◽  
Dark Count ◽  
Infinite Memory ◽  
Temporal Complexity ◽  
Physiological Processes ◽  
Diffusion Entropy ◽  
Germinating Seeds

We study the emission of photons from germinating seeds using an experimental technique designed to detect light of extremely small intensity. We analyze the dark count signal without germinating seeds as well as the photon emission during the germination process. The technique of analysis adopted here, called diffusion entropy analysis (DEA) and originally designed to measure the temporal complexity of astrophysical, sociological and physiological processes, rests on Kolmogorov complexity. The updated version of DEA used in this paper is designed to determine if the signal complexity is generated either by non-ergodic crucial events with a non-stationary correlation function or by the infinite memory of a stationary but non-integrable correlation function or by a mixture of both processes. We find that dark count yields the ordinary scaling, thereby showing that no complexity of either kinds may occur without any seeds in the chamber. In the presence of seeds in the chamber anomalous scaling emerges, reminiscent of that found in neuro-physiological processes. However, this is a mixture of both processes and with the progress of germination the non-ergodic component tends to vanish and complexity becomes dominated by the stationary infinite memory. We illustrate some conjectures ranging from stress induced annihilation of crucial events to the emergence of quantum coherence.

scholarly journals Biophotons: low signal/noise ratio reveals crucial events

2019 ◽  
Author(s):  
Maurizio Benfatto ◽  
Elisabetta Pace ◽  
Catalina Curceanu ◽  
Alessandro Scordo ◽  
Alberto Clozza ◽  
...  
Keyword(s):  
Correlation Function ◽  
Quantum Coherence ◽  
Photon Emission ◽  
Dark Count ◽  
Infinite Memory ◽  
Signal Noise ◽  
Temporal Complexity ◽  
Physiological Processes ◽  
Noise Ratio ◽  
Germinating Seeds

We study the emission of photons from germinating seeds using an experimental technique designed to detect photons of extremely small intensity when the signal/noise ratio is low. We analyze the dark count signal in the absence of germinating seeds as well as the photon emission during the germination process. The technique of analysis adopted here was originally designed to measure the temporal complexity of astrophysical, sociological and physiological processes. The foundation of this method, called Diffusion Entropy Analysis (DEA), rests on Kolmogorov complexity. The updated version of DEA used in this paper is designed to determine if the signal complexity is generated by either non-ergodic crucial events with a non-stationary correlation function or by the infinite memory of a stationary but non-integrable correlation function or by a mixture of both processes. We find that dark count yields the ordinary scaling, thereby showing that no complexity of either kinds may occur in the absence of any seeds in the chamber. In the presence of seeds in the chamber anomalous scaling emerges, reminiscent of that found in neuro-physiological processes. However, this is a mixture of both processes and with the progress of germination the non-ergodic component tends to vanish and complexity is dominated by the stationary infinite memory. We argue that this may be a sign of quantum coherence that according to some authors is the important ingredient of cognition.

The coupling of single-photon exciton–biexciton quantum dot and cavity

2017 ◽  
Vol 26 (03) ◽  
pp. 1750029 ◽  
Author(s):  
Lina Jaya Diguna ◽  
Yudi Darma ◽  
Muhammad Danang Birowosuto
Keyword(s):  
Correlation Function ◽  
Quantum Dot ◽  
Density Matrix ◽  
High Probability ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Properties ◽  
Proposed Model ◽  
Cavity System

We investigate the influence of multiple excitons on the photon emission properties of a quantum dot (QD)-cavity system via the master equation for the density matrix. We show that in the intermediate to strong coupling regimes, the multiple excitons lead to the suppressed QD emissions as well as the absence of anti-crossing near zero detuning, arising from the interaction between the multiple excitons and cavity. Furthermore, we analyze the role of the cavity-biexciton detuning in the photon emission properties of cavity and exciton through the second-order correlation function. The small cavity-biexciton detuning yields the significant Purcell effect and the high probability of single photon emissions. The proposed model offers the fundamental approach in developing efficient single-photon emitting devices.

Biophysical and functional characterizations of recombinant RimI acetyltransferase from Mycobacterium tuberculosis

2019 ◽  
Vol 51 (9) ◽  
pp. 960-968
Author(s):  
Meijing Hou ◽  
Jie Zhuang ◽  
Shihui Fan ◽  
Huilin Wang ◽  
Chenyun Guo ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Quantum Coherence ◽  
Protein Modification ◽  
Structural Information ◽  
Biochemical Properties ◽  
Structural Determination ◽  
Physiological Processes ◽  
High Quality Protein ◽  
Wide Range ◽  
Docking Approach

Abstract Nα-acetylation is a universal protein modification related to a wide range of physiological processes in eukaryotes and prokaryotes. RimI, an Nα-acetyltransferase in Mycobacterium tuberculosis, is responsible for the acetylation of the α-amino group of the N-terminal residue in the ribosomal protein S18. Despite growing evidence that protein acetylation may be correlated with the pathogenesis of tuberculosis, no structural information is yet available for mechanistically understanding the MtRimI acetylation. To enable structural studies for MtRimI, we constructed a serial of recombinant MtRimI proteins and assessed their biochemical properties. We then chose an optimal construct MtRimIC21A4-153 and expressed and purified the truncated high-quality protein for further biophysical and functional characterizations. The 2D 1H-15N heteronuclear single quantum coherence spectrum of MtRimIC21A4-153 exhibits wider chemical shift dispersion and favorable peak isolation, indicating that MtRimIC21A4-153 is amendable for further structural determination. Moreover, bio-layer interferometry experiments showed that MtRimIC21A4-153 possessed similar micromolar affinity to full-length MtRimI for binding the hexapeptide substrate Ala-Arg-Tyr-Phe-Arg-Arg. Enzyme kinetic assays also exhibited that MtRimIC21A4-153 had almost identical enzymatic activity to MtRimI, indicating insignificant influence of the recombinant variations on enzymatic functions. Furthermore, binding sites of the peptide were predicted by molecular docking approach, suggesting that this substrate binds to MtRimI primarily through electrostatic and hydrogen bonding interactions. Our results lay a foundation for the further structural determination and dynamics detection of MtRimI.

scholarly journals Electrocortical temporal complexity during wakefulness and sleep: an updated account

2020 ◽  
Author(s):  
Joaquín González ◽  
Matias Cavelli ◽  
Alejandra Mondino ◽  
Claudia Pascovich ◽  
Santiago Castro-Zaballa ◽  
...  
Keyword(s):  
Electrode Configuration ◽  
Behavioral State ◽  
Complex Activity ◽  
Temporal Complexity ◽  
Physiological Processes ◽  
Brain Signals ◽  
Controversial Topic ◽  
The Brain

AbstractThe states of sleep and wakefulness are critical physiological processes associated with different brain patterns of activity. The intracranial electroencephalogram allows us to measure these changes, thus, it is a critical tool for its study. Recently, we showed that the electrocortical temporal complexity decreased from wakefulness to sleep. Nevertheless, the origin of this complex activity remains a controversial topic due to the existence of possible artifacts contaminating the brain signals. In this work, we showed that complexity decreases during sleep, independently of the electrode configuration employed. This fact strongly suggests that the basis for the behavioral-state differences in complexity does not have an extracranial origin; i.e., generated from the brain.

scholarly journals Superior properties in room-temperature colloidal-dot quantum emitters revealed by ultralow-dark-count detections of temporally-purified single photons

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Toshiyuki Ihara ◽  
Shigehito Miki ◽  
Toshiki Yamada ◽  
Takahiro Kaji ◽  
Akira Otomo ◽  
...  
Keyword(s):  
Room Temperature ◽  
Quantum Information Processing ◽  
Single Photon ◽  
Photon Emission ◽  
Light Sources ◽  
Single Photons ◽  
Dark Count ◽  
Photon Detectors ◽  
High Quality ◽  
Quantum Emitters

Abstract The realization of high-quality quantum emitters that can operate at room temperature is important for accelerating the application of quantum technologies, such as quantum communication, quantum information processing, and quantum metrology. In this work, we study the photon-antibunching properties on room-temperature emission from individual colloidal quantum dots (CQDs) using superconducting-nanowire single-photon detectors and temporal filtering of the photoluminescence decay curve. We find that high single-photon purities and high photon-generation rates can be simultaneously achieved by removing the signals originating from the sequential two-photon emission of biexcitons created by multiple excitation pulses. We successfully demonstrate that the ultrahigh performance of the room-temperature single-photon sources showing g(2)(0) ≪ 10−2 can be confirmed by the ultralow-dark-count detection of the temporally purified single photons. These findings provide strong evidence for the attractiveness of CQDs as candidates for high-quality room-temperature quantum light sources.

Diffusion entropy analysis in billiard systems

2019 ◽  
Vol 100 (4) ◽  
Author(s):  
Gabriel I. Díaz ◽  
Matheus S. Palmero ◽  
Iberê Luiz Caldas ◽  
Edson D. Leonel
Keyword(s):  
Entropy Analysis ◽  
Diffusion Entropy

Nonextensive Diffusion Entropy Analysis and Teen Birth Phenomena

2004 ◽  
Author(s):  
N. Scafetta ◽  
P. Grigolin
Keyword(s):  
Complex System ◽  
Time Series ◽  
Entropy Analysis ◽  
Fractal Structures ◽  
Mathematical Methods ◽  
Teen Birth ◽  
Working Definition ◽  
Diffusion Entropy ◽  
Wavelet Multiresolution Analysis ◽  
Definition Of

A complex process is often a balance between nonscaling and scaling components. We show how the nonextensive Tsallis g-entropy indicator may be interpreted as a measure of the nonscaling condition in time series. This is done by applying the nonextensive entropy formalism to the diffusion entropy analysis (DEA). We apply the analysis to the study of the teen birth phenomenon. We find that the number of unmarried teen births is strongly influenced by social processes that induce an anomalous memory in the data. This memory is related to the strength of the nonscaling component of the signal and is more intense than that in the married teen birth time series. By using a wavelet multiresolution analysis, we attempt to provide a social interpretation of this effect…. One of the most exciting and rapidly developing areas of modern research is the quantitative study of "complexity." Complexity has special interdisciplinary impacts in the fields of physics, mathematics, information science, biology, sociology, and medicine. No definition of a complex system has been universally embraced, so here we adopt the working definition, "an arrangement of parts so intricate as to be hard to understand or deal with." Therefore, the main goal of the science of complexity is to develop mathematical methods in order to discriminate among the fundamental microscopic and macroscopic constituents of a complex system and to describe their interrelations in a concise way. Experiments usually yield results in the form of time series for physical observables. Typically, these time series contain both a slow regular variation, usually called a "signal," and a rapid erratic fluctuation, usually called "noise." Historically, the techniques applied to processing such time series have been based on equilibrium statistical mechanics and, therefore, they are not applicable to phenomena far from equilibrium. Among the fluctuating phenomena, a particularly important place is occupied by those phenomena characterized by some type of self-similar or scaling-fractal structures [4]. In this chapter we show that the nonextensive Tsallis g-entropy indicator may be interpreted as a measure of the strength of the nonscaling component of a time series.

Sign in / Sign up

Export Citation Format

Share Document