Principle Of Reversibility Research Articles

Evaluation of drug resistance mutations in patients with chronic hepatitis B.

Mutations occurring in viral polymerase gene of hepatitis B virus (HBV) due to the use of nucleos(t)id analogs reduce the activity of the drugs by causing antiviral resistance. In this study, it was aimed to evaluate mutations responsible for drug resistance and drug resistance mutation rates in patients followed up by the diagnosis of chronic hepatitis B (CHB). A total of 318 CHB patients were included in the study. HBV mutations were detected using the INNO-LiPA commercial kit based on the reverse hybridization principle. Drug resistance mutation was detected in 46.86% (149/318) of the patients. The rates of drug resistance were found 36.79% (117/318) for lamivudine resistance, 12.58% (40/318) for entecavir (ETV), and 7.86% (25/318) for adefovir. In 10 patients, the possible tenofovir (TDF) resistance (3.14%) was found. Single-drug and double-drug resistances were detected in 34.59% and in 11.01% of the patients, respectively. Triple drug resistance was detected in only 1.26% of the patients. Unlike various studies in Turkey and in other countries, remarkable resistance to ETV and TDF were found in this study. The high rate of the probable TDF resistance was striking, with 3.14%.

Light-driven molecular trap enables bidirectional manipulation of dynamic covalent systems.

Bond formation between two molecular entities in a closed system strictly obeys the principle of microscopic reversibility and occurs in favour of the thermodynamically more stable product. Here, we demonstrate how light can bypass this fundamental limitation by driving and controlling the reversible bimolecular reaction between an N-nucleophile and a photoswitchable carbonyl electrophile. Light-driven tautomerization cycles reverse the reactivity of the C=O/C=N-electrophiles ('umpolung') to activate substrates and remove products, respectively, solely depending on the illumination wavelength. By applying either red or blue light, selective and nearly quantitative intermolecular bond formation/scission can be achieved, even if the underlying condensation/hydrolysis equilibrium is thermodynamically disfavoured. Exploiting light-driven in situ C=N exchange, our approach can be used to externally regulate a closed dynamic covalent system by actively and reversibly removing specific components, resembling a molecular and bidirectional version of a macroscopic Dean-Stark trap.

Time reversal for wave refocusing and scatterer detection using machine learning

Conventional seismic migration and inversion are inherently limited in their ability to detect and characterize subsurface elements smaller than the seismic wavelength, such as faults, pinchouts, karsts, fractures, fluid contact, etc. However, those elements, playing an important role in seismic exploration and production, act as scattering objects, which can be effectively detected and positioned using the time reversal (TR) principle. We use TR to spatially localize subsurface sources in passive seismic scenarios and scatterers in active seismic surveys, both having the physical properties of a point diffractor. The method uses numerical back propagation of the time-reversed registered wavefield followed by an analysis of its obtained focusing, based on a supervised learning approach. In this novel approach, no imaging condition is applied. In addition, it does not require knowledge of the source wavelet and it accounts for multiple scattering. The usefulness of the method is demonstrated using synthetic and field examples.

Nuclease Activity of the DNA Polymerases: An Evasion of Microscopic Reversibility Leading to Fidelity in Excess of Kinetic Control Levels

The exonuclease and endonuclease activities of the DNA polymerases, which extend their proof-reading capabilities and maintain high fidelity in the replication process, apparently conflict with the principle of microscopic reversibility. However, in-depth mechanistic analysis of the reactions leads to fascinating insights into the kinetic and thermodynamic effects controlling the replication of the primary genetic material. Thus, nucleotide addition and excision involve different pathways, although a violation of microscopic reversibility is avoided as the overall reaction does not reach equilibrium. Intriguingly, however, this allows the fidelity levels to exceed those expected from simple kinetic control.

Computational study on focused microwave thermotherapy for knee pathological treatment

This study is a computational study on focused microwave thermotherapy for knee pathological treatment using the time reversal (TR) principle in musculoskeletal disorders. The authors presented a modified TR algorithm with amplitude compensation for an accurate beam focusing of the knee tumour location in a lossy medium. Furthermore, they proposed a new approach called the truncated threshold method, which could be used to apply an effective beam focusing on a tumour location in the knee while the unwanted hot spots are controlled in the normal tissue region. Compared to the other existing methods, this new approach has the advantages of being implemented simply in the unwanted hot spot control and having a similar performance to the beam focusing on the target location. The application of the proposed algorithm and the new hot spot control method to knee pathological tissue achieved acceptable electromagnetic (EM) and thermal results. The anatomical based two-dimensional (2D) knee model for the simulation analysis was implemented using a segmentation result of the Korean human body model obtained from magnetic resonance imaging. 2D finite-difference time-domain electromagnetic and thermal solvers were developed and applied to conduct the 915 MHz focused microwave thermotherapy for knee pathological treatment.

Acoustic nonreciprocity in a lattice incorporating nonlinearity, asymmetry, and internal scale hierarchy: Experimental study.

In linear time-invariant systems acoustic reciprocity holds by the Onsager-Casimir principle of microscopic reversibility, and it can be broken only by odd external biases, nonlinearities, or time-dependent properties. Recently it was shown that one-dimensional lattices composed of a finite number of identical nonlinear cells with internal scale hierarchy and asymmetry exhibit nonreciprocity both locally and globally. Considering a single cell composed of a large scale nonlinearly coupled to a small scale, local dynamic nonreciprocity corresponds to vibration energy transfer from the large to the small scale, but absence of energy transfer (and localization) from the small to the large scale. This has been recently proven both theoretically and experimentally. Then, considering the entire lattice, global acoustic nonreciprocity has been recently proven theoretically, corresponding to preferential energy transfer within the lattice under transient excitation applied at one of its boundaries, and absence of similar energy transfer (and localization) when the excitation is applied at its other boundary. This work provides experimental validation of the global acoustic nonreciprocity with a one-dimensional asymmetric lattice composed of three cells, with each cell incorporating nonlinearly coupled large and small scales. Due to the intentional asymmetry of the lattice, low impulsive excitations applied to one of its boundaries result in wave transmission through the lattice, whereas when the same excitations are applied to the other end, they lead in energy localization at the boundary and absence of wave transmission. This global nonreciprocity depends critically on energy (i.e., the intensity of the applied impulses), and reduced-order models recover the nonreciprocal acoustics and clarify the nonlinear mechanism generating nonreciprocity in this system.

Modified Linnik microscopic interferometry for quantitative depth evaluation of diffraction-limited microgroove

The quality control of microgrooves is extremely crucial to ensure the performance and stability of microstructures and improve their fabrication efficiency. This paper introduces a novel optical inspection method and a modified Linnik microscopic interferometer measurement system to detect the depth of microgrooves with a width less than the diffraction limit. Using this optical method, the depth of diffraction-limited microgrooves can be related to the near-field optical phase difference, which cannot be practically observed but can be computed from practical far-field observations. Thus, a modified Linnik microscopic interferometer system based on three identical objective lenses and an optical path reversibility principle were developed. In addition, experiments for standard grating microgrooves on the silicon surface were carried out to demonstrate the feasibility and repeatability of the proposed method and developed measurement system.

Stochastically pumped adaptation and directional motion of molecular machines

Recent developments in synthetic molecular motors and pumps have sprung from a remarkable confluence of experiment and theory. Synthetic accomplishments have facilitated the ability to design and create molecules, many of them featuring mechanically bonded components, to carry out specific functions in their environment—walking along a polymeric track, unidirectional circling of one ring about another, synthesizing stereoisomers according to an external protocol, or pumping rings onto a long rod-like molecule to form and maintain high-energy, complex, nonequilibrium structures from simpler antecedents. Progress in the theory of nanoscale stochastic thermodynamics, specifically the generalization and extension of the principle of microscopic reversibility to the single-molecule regime, has enhanced the understanding of the design requirements for achieving strong unidirectional motion and high efficiency of these synthetic molecular machines for harnessing energy from external fluctuations to carry out mechanical and/or chemical functions in their environment. A key insight is that the interaction between the fluctuations and the transition state energies plays a central role in determining the steady-state concentrations. Kinetic asymmetry, a requirement for stochastic adaptation, occurs when there is an imbalance in the effect of the fluctuations on the forward and reverse rate constants. Because of strong viscosity, the motions of the machine can be viewed as mechanical equilibrium processes where mechanical resonances are simply impossible but where the probability distributions for the state occupancies and trajectories are very different from those that would be expected at thermodynamic equilibrium.

IDENTIFIKASI MASALAH APLIKASI TEKNOLOGI PENGOLAHAN AIR PAYAU DENGAN SISTEM RO DI KABUPATEN REMBANG DAN CARA MENGATASINYA

A brackish water treatment process technology based on reverse osmosis principle has been applied in an Islamic school community “Raudlatuttalibin”, Rembang, since July 2008. Production capacity of the water treatment plant was designed 10M3 of drinking water per day. After running the system for one and a half years, a lot of problems were consecutively appearing untill the end of March 2010. This identification activity clarified all problems in detail and explained how to solve them. They are not only technical problems, but also social and cultural problems of the community. To solve them it must be started from increasing the capability of operators and applying the clean production concept. Finally by changing all the technically broken spareparts and running the RO unit system properly, they will be guaranteed to be able to produce good quality of drinking water. Keywords : water treatment plant, reverse osmosis, technical social problems.

Nonreciprocity in the dynamics of coupled oscillators with nonlinearity, asymmetry, and scale hierarchy.

In linear time-invariant dynamical and acoustical systems, reciprocity holds by the Onsager-Casimir principle of microscopic reversibility, and this can be broken only by odd external biases, nonlinearities, or time-dependent properties. A concept is proposed in this work for breaking dynamic reciprocity based on irreversible nonlinear energy transfers from large to small scales in a system with nonlinear hierarchical internal structure, asymmetry, and intentional strong stiffness nonlinearity. The resulting nonreciprocal large-to-small scale energy transfers mimic analogous nonlinear energy transfer cascades that occur in nature (e.g., in turbulent flows), and are caused by the strong frequency-energy dependence of the essentially nonlinear small-scale components of the system considered. The theoretical part of this work is mainly based on action-angle transformations, followed by direct numerical simulations of the resulting system of nonlinear coupled oscillators. The experimental part considers a system with two scales-a linear large-scale oscillator coupled to a small scale by a nonlinear spring-and validates the theoretical findings demonstrating nonreciprocal large-to-small scale energy transfer. The proposed study promotes a paradigm for designing nonreciprocal acoustic materials harnessing strong nonlinearity, which in a future application will be implemented in designing lattices incorporating nonlinear hierarchical internal structures, asymmetry, and scale mixing.

Non-uniqueness of the multi-temperature law of mass action. Application to 2T plasma composition calculation by means of a collisional-radiative model

This work is devoted to the calculation of the composition for a monoatomic plasma (argon in the case presented) for which the assumption of thermal equilibrium is not realized. The plasma composition is obtained from a CR model, taking into account free electrons and a great number of electronic levels of Ar atoms and Ar+ ions. This model is based on a large set of transition probabilities and reaction rate coefficients for radiative processes (spontaneous emission and radiative recombination) and on an extended database of direct and reverse reaction rate coefficients for collisional processes (excitation/de-excitation and ionization/recombination mechanisms). Assuming Maxwellian energy distribution functions for electrons and heavy chemical species, detailed balance equations are determined for all kind of reactions in the frame of the micro reversibility principle. From these balance equations, reverse rate coefficients are calculated as a function of direct reaction rates and of electrons and heavy particles translation temperatures (T e and T h respectively). Particular attention is paid to problematic chemical reactions with electrons involved on one side and only heavy species on the other side such as: Ar + Ar → Ar + Ar+ + e. The detailed balance relations obtained for ionization/recombination processes demonstrate the non-uniqueness of the multi-temperature Saha-Eggert law (i.e. non-uniqueness of the multi-temperature law of mass action). Multi-temperature argon plasma compositions obtained in the present work exhibit abrupt density variations. These sharp variations are characteristic of the transition between the domination of heavy particle reactions (at low temperature) and the predominance of electron collisions (at high temperature).

Broadband VHF Localization of Lightning Radiation Sources by EMTR

In this paper, a novel mapping algorithm by applying electromagnetic time reversal (EMTR) technique to broadband very high frequency (VHF) for the direction-of-arrival (DOA) estimation of lightning radiation sources is proposed and validated. Based on the theory of array signal DOA estimation and time reversal (TR) principle, the lightning radiation receiving model with broadband VHF array is established, and thereafter the TR synthesized signal for arbitrary direction is derived. It is proved that the direction with the maximum norm of synthesized signal is the optimal estimation for the incident direction, and hence the procedure for the EMTR-VHF method is derived. Numerical simulations are conducted for testing the algorithm and investigating the relationships between the array spatial resolution and the available signal frequencies, robustness of the algorithm, et al . Two metrics, amplitude ratio and energy ratio, are devised to filter false locations, and the acceptable ranges of them are further estimated by simulation. In order to further validate the EMTR-VHF algorithm, field experiments are carried out. The results show that the EMTR-VHF method performs well, especially for the sources with low elevations, with the error less than 1°. Finally, the application of EMTR-VHF method in locating a negative cloud-to-ground flash is presented. Temporal and spatial development of the leader-return stroke sequence could be well depicted. The results are generally consistent with the VHF interferometry technique, which confirm its ability in lightning localization. Besides, the discrepancy between this algorithm and broadband interferometry method are documented.

Bromamine Decomposition Revisited: A Holistic Approach for Analyzing Acid and Base Catalysis Kinetics.

Chloramine chemistry is complex, with a variety of reactions occurring in series and parallel and many that are acid or base catalyzed, resulting in numerous rate constants. Bromide presence increases system complexity even further with possible bromamine and bromochloramine formation. Therefore, techniques for parameter estimation must address this complexity through thoughtful experimental design and robust data analysis approaches. The current research outlines a rational basis for constrained data fitting using Brønsted theory, application of the microscopic reversibility principle to reversible acid or base catalyzed reactions, and characterization of the relative significance of parallel reactions using fictive product tracking. This holistic approach was used on a comprehensive and well-documented data set for bromamine decomposition, allowing new interpretations of existing data by revealing that a previously published reaction scheme was not robust; it was not able to describe monobromamine or dibromamine decay outside of the conditions for which it was calibrated. The current research's simplified model (3 reactions, 17 constants) represented the experimental data better than the previously published model (4 reactions, 28 constants). A final model evaluation was conducted based on representative drinking water conditions to determine a minimal model (3 reactions, 8 constants) applicable for drinking water conditions.

Carbon Kinetic Isotope Effects and the Mechanisms of Acid-Catalyzed Decarboxylation of 2,4-Dimethoxybenzoic Acid and CO2 Incorporation into 1,3-Dimethoxybenzene.

The rate of decarboxylation of 2,4-dimethoxybenzoic acid (1) is accelerated in parallel to the extent that the carboxyl group acquires a second proton (1H+). However, the conjugate acid would resist C-C bond breaking as that would lead to formation of doubly protonated CO2. An alternative via formation of a higher-energy protonated phenyl tautomer (2H+) prior to C-C bond breaking would produce protonated CO2, an energetically inaccessible species that can be avoided by transfer of the carboxyl proton to water in the same step. Headspace sampling of CO2 that evolves in the acid-catalyzed process and analysis by GC-IRMS gives a smaller than expected value of 1.022 for the carbon kinetic isotope (CKIE), k12/k13. While this value establishes that C-C cleavage is part of the rate-determining process, intrinsic CKIEs for decarboxylation reactions are typically greater than 1.03. Computational analysis of the C-C bond cleavage from 2H+ gives an intrinsic CKIE of 1.051 and suggests two partially rate-determining steps in the decarboxylation of 1: transfer of the second carboxyl proton to the adjacent phenyl carbon and C-C cleavage in which the carboxyl proton is also transferred to water. Applying the principle of microscopic reversibility to fixation of CO2 in acidic solutions reveals the importance of proton transfers to both carbon and oxygen in the overall fixation process.

Study and Design Sailboat Type Dinghy

The Objectives of this research are 1) to study the form of Dinghy boat 2) to design a Dinghy boat by using D Ronald K. Kiss Ship’s Iterative Process on Design Spiral, by studying the model’s data of Dinghy sailboats, including related Ideas, theories, and interviews with the yacht racing association of Thailand’s officers. The Purposive Sampling Method as used. After studied the form of the Dinghy boat, the designing process then started by using collected data, through analytical processes with conceptual framework for product design; The Quality Function Deployment, the Theory of Inventive Problem Solving, the Design Spiral which is an iterative Process, and the Reverse Engineering Principle. The experts from both the fields of Industrial Product Design and Sailing Boat, whom concern Dinghy Boat format, were included to evaluate the designing and model constructing process. The statistical methods used were Percentage, Median and Standard Deviation (SD.). The research found that 1) the current type of Dinghy sailboat is still unsafe for novice sailors; It is difficult for practicing, limited on sailor's weight, very difficult to relocate and take care of, it also were built from the expensive materials 2) In designing, the researcher designed the boat's hull by concentrate on its floating center The middle movement, which would have an effect on its floating aspect, which might tilt the boat, to be straight and highly secure. Researcher designed the parts to be able to disassemble and redesign shapes, and use wood as a material for maintenance purpose in accordance with the technical requirements that expected for Dinghy boat, from the Sailing Boat experts under Yacht racing association of Thailand. In the opinions of the honorable experts, the Dinghy Boat type 1 was scored following these factors; Meet the usage demand of the boat (Mean = 3.88, SD. = 0.33) The determination of size and dimension of the boat (Mean = 4.13, SD. = 0.33) The line pattern and shape of the boat ( Mean = 3.88, SD. = 0.33).

Violation of light beam reversibility principle in optical media with a random quasi-zero refractive index

We report on experimental and theoretical evidence of the violation of one of the fundamental principles in the Fresnel optics, namely, light beam reversibility, in new nanostructured composite metamaterials with silver nanoparticle in a polymer matrix. It is shown that optical transmittance of (PMMA + Ag)/glass samples in counter directions is not the same. We propose a theoretical explanation of this phenomenon based on the effect of photon localization on the surface of the composite layer with a random quasizero refractive index.

Art Scott and Michael Frank on energy-efficient computing

Clock speeds of computing chips have leveled off dramatically since 2005, and putting more cores in systems on a chip (SoC) has produced more heat, adding a new ceiling to further advances. Leading-edge researchers, like Mike Frank, and dedicated technologists with a wealth of experience, like Art Scott, represent a new vanguard of the leap-forward beyond Dennard scaling and Landauer's limit. Art looks for ways to reduce energy consumption and Mike looks for ways to "architect" future chips according to principles of reversibility. Is the future in reversible, adiabatic computing and simpler architectures using posit arithmetic? My guests think so.

FEEDBACK AND SELF REGULATION IN WRITING LEARNING ASSESMENT IN JUNIOR HIGH SCHOOL

This article aims to analyze the pattern of feedback and self-regulation in writing assessment in junior high school. The feedback in the writing assessment in junior high school is done quantitatively in the form of a score in the final product. Self-regulation in the assessment as a learning tool is done in the form of reflections on competencies that have been mastered and have not been mastered. The implementation of feedback and self-regulation in the learning assessment in junior high school is not suitable yet in terms of reversal principle and self-regulation in the context of assessment as a learning tool.

The reverse precautionary principle: science, the environment and the salmon aquaculture industry in Macquarie Harbour, Tasmania, Australia

Science is frequently used by opposing sides in environment–development debates. Scientific input from an environmental perspective can be inhibited if those in favour of development control research funding. We test whether such a situation can result in outcomes desired by neither of the protagonists, and seek to identify how negative outcomes can be avoided, using the example of fish farming in Macquarie Harbour, Tasmania. A marked decline in dissolved oxygen (DO) at 19–21m depth in Macquarie Harbour, Tasmania, occurred between 2009 and 2011. DO continues to be low. DO change was associated with changes in the benthic biota, with effects extending from fish farms into the Tasmanian Wilderness World Heritage Area and threatening a Tasmanian endemic fish. The reverse precautionary response of industry and government was to undertake further research because the causes of the changes were not fully understood. We present simple graphs and analyses that suggest that the only substantial predictor of benthic DO reduction is fish production from marine farms, with variability in discharge, catchment rainfall, wind speed, sea surface temperatures and sea level pressure having no effect. Adaptive management of fish farming in Macquarie Harbour seems to require an estuary-wide approach rather than the current attention to the effects of single pens. The broader implications of the case study are that the science related to the environmental impacts of an industry needs to be undertaken by scientists in secure positions funded independently of industry and government.

Wild Voices: Mimicry, Reversal, Metaphor, and the Emergence of Language

Why is it that, out of 220 primate species, we are the only one that talks? The relative inflexibility of primate vocal signaling reflects audience pressure for reliability. Where interests conflict, listeners’ resistance to being deceived drives signalers to limit their vocal repertoire to signals that cannot be faked. This constraint was lifted in the human case, we argue, because the original victims of our species’ first deceptive vocalizations were nonhuman animals. When our ancestors were vulnerable hominins equipped with limited weaponry, they kept predators away by increasing the range and diversity of their vocal calls. This led to choral singing, primarily by females, and deceptive mimicry of animal calls, primarily by scavenging and hunting males. A critical feature of our model is the core principle of reversal, whereby deceptive signals aimed originally by a coalition against an external target are subsequently redeployed for honest communicative purposes within the group. We argue that this ...