ARTICLE | doi:10.20944/preprints202312.0224.v1
Subject: Physical Sciences, Other Keywords: BSM physics; BBN constraints; neutrino oscillations; sterile neutrino; lepton asymmetry; drak radiation.
Online: 4 December 2023 (17:30:57 CET)
We use Big Bang Nucleosynthesis (BBN) to probe Beyond Standard Model physics in the neutrino sector. Recently the abundances of primordially produced light elements D and He-4 were determined from observations with better accuracy. The good agreement between the theoretically predicted abundances of primordially produced and derived from observations light elements allows to update the BBN constraints on Beyond Standard Models (BSM) physics. We provide numerical analysis of several BSM models of BBN and obtain precise cosmological constraints and indications for new neutrino physics. Namely, we derive more stringent BBN constraints on electron neutrino-sterile neutrino oscillations corresponding to 1% uncertainty of the observational determination of the primordial He-4. The cosmological constraints are obtained both for the case of zero and non-zero initial population of the sterle neutrino state. Then in a degenerate BBN model with neutrino νe↔νs oscillations we analyze the change of the cosmological constraints in case lepton asymmetry L is big enough to suppress oscillations. We obtain constraints on the lepton asymmetry L . We discuss a possible solution to the dark radiation problem in degenerate BBN models with νe↔νs oscillations in case L is large enough to suppress neutrino oscillations during BBN epoch. Interestingly, the required value of L for solving DR problem is close to L indicated by EMPRESS experiment and close to the value of lepton asymmetry necessary to relax Hubble tension.
REVIEW | doi:10.20944/preprints202311.1630.v1
Subject: Physical Sciences, Other Keywords: Nonlinear Schrö dinger Equation; NLSE; energy-conserving methods; Hamiltonian Boundary Value Methods; HBVMs; spectral accuracy
Online: 28 November 2023 (01:44:26 CET)
In this review we collect some recent achievements in the accurate and efficient solution of the Nonlinear Schrödinger Equation (NLSE), with the preservation of its Hamiltonian structure. This is achieved by using the energy-conserving Runge-Kutta methods named Hamiltonian Boundary Value Methods (HBVMs) after a proper space semi-discretization. The main facts about HBVMs, along with their application for solving the given problem, are here recalled and explained in detail. In particular, their use as spectral methods in time, which allows efficiently solving the problems with spectral space-time accuracy.
ARTICLE | doi:10.20944/preprints202311.0955.v2
Subject: Physical Sciences, Other Keywords: Pilates; perceived value; continuous behavioral intention; Extended Theory of Planned Behavior (ETPB)
Online: 22 November 2023 (14:53:21 CET)
This study examined the relationships between attitude, subjective norms, perceived behavioral control, and behavioral intention through the perceived value of Pilates participants. The participants of this study were 301 Pilates students using Pilates studios located in Busan, Ulsan, and Gyeongbuk Province. The participants were selected by convenient sampling, a non-probability sampling method. The collected data were analyzed using descriptive analysis, reliability analysis, correlation analysis, confirmatory factor analysis, and structural equation modeling analysis using SPSS 22.0 and AMOS 24.0. The results can be summarized as follows. First, among the three subfactors of perceived value, functional and social values had a positive effect on attitude. Second, attitude, subjective norms, and perceived behavioral control, which are three main components of the Theory of Planned Behavior, had a positive effect on the behavioral intention for Pilates. These results suggest that Pilates instructors require meticulous planning and efforts to develop an environment for promoting spontaneous interest and participation to attract students and engage their attention and interest in the field.
ARTICLE | doi:10.20944/preprints202311.0365.v1
Subject: Physical Sciences, Other Keywords: ADMET; antimicrobial agents; effects of chain length; molecular docking; regioselective acylation; structure-activity relationship; sugar fatty acid ester (SFAE).
Online: 6 November 2023 (15:08:45 CET)
The approval of sucrose fatty acid esters (SFAEs) as food additives/preservatives has triggered enormous interest in discovering new applications for these materials. Accordingly, many researchers reported that SFAEs consist of various sugar moieties, and hydrophobic side chains are highly active against certain fungal species. The combination of chain length and site of acylation is crucial in endowing the SFAE with high antimicrobial potency against Aspergillus species. Following several important studies, we herein present the synthesis and an assessment of the effects of acylation site and chain length (i.e., C-6 vs. C-2, C-3, C-4, and long-chain vs. short-chain) on the antimicrobial activity of mannopyranoside fatty acid esters. In vitro tests revealed that the fatty acid chain length in mannopyranoside esters significantly affects the antifungal activity where C12 chains are more potent against Aspergillus species. In terms of acylation site, mannopyranoside esters with a C8 chain substituted at the C-6 position are more active in antifungal inhibition. Molecular docking also revealed that these mannopyranoside esters had comparatively better stable binding energy, and hence better inhibition, with the fungal enzymes lanosterol 14-alpha-demethylase (3LD6), urate oxidase (1R51), and glucoamylase (1KUL) than the standard antifungal drug fluconazole. Additionally, the thermodynamic, orbital, drug-likeness, and safety profiles of these mannopyranoside esters were calculated and discussed, along with the structure-activity relationships (SAR). This study thus highlights the importance of the acylation site and lipid-like fatty acid chain length that govern the antimicrobial activity of mannopyranoside-based SFAE.
ARTICLE | doi:10.20944/preprints202310.1944.v1
Subject: Physical Sciences, Other Keywords: universe evolution; gravitational repulsion and antiparticles; baryon symmetry of the universe
Online: 30 October 2023 (16:11:23 CET)
By combining general relativity and CPT symmetry, the theory of CPT gravity predicts gravitational repulsion between matter and CPT-transformed matter, i.e. antimatter inhabiting an inverted space-time. Such repulsive gravity turned out to be an excellent candidate for explaining the accelerated expansion of the Universe, without the need for dark energy. The recent results of the ALPHA-g experiment, which show gravitational attraction between antihydrogen atoms and the Earth, seem to undermine this success in the cosmological field. Analyzing the above theory, we find two solutions that can be consistent with the experimental results, while preserving the large-scale gravitational repulsion. The first highlights how repulsive gravity can be the result of the interaction with an inverted space-time, but occupied by matter and not antimatter, and therefore the antimatter present in our space-time has no reason to exhibit gravitational repulsion. The second retains the original CPT transformation, resulting in repulsive gravity between matter and antimatter, but with the caveat that antimatter immersed in our space-time cannot exhibit the PT transformation which is the cause of the repulsion. Finally, it is shown that, in a Newtonian approximation of the geodesic equation, time reversal is not a necessary operation for repulsive gravity, therefore opening the possibility of an expanding cosmos with a single time direction.
ARTICLE | doi:10.20944/preprints202310.1751.v1
Subject: Physical Sciences, Other Keywords: Lightning; Land Cover and Land Use; Topographic Effects, Itacaiúnas River Hydrographic Basin
Online: 30 October 2023 (06:52:52 CET)
Keywords: Lightning; Land Cover and Land Use; Topographic Effects, Itacaiúnas River Hydrographic Basin
REVIEW | doi:10.20944/preprints202310.1515.v1
Subject: Physical Sciences, Other Keywords: seasonality; autism; time of birth; infection; nutrition; vitamin; geographic location; photoperiod; immigration
Online: 24 October 2023 (10:18:59 CEST)
This paper offers an in-depth exploration of the complex relationship between seasonality and Autism Spectrum Disorder (ASD). It reviews existing research, providing a comprehensive summary of findings and highlighting the multifaceted dimensions of seasonality as an environmental factor that influences the etiology of ASD. The discussion encompasses various factors, including birth months, maternal health, dietary choices, and vitamin D deficiency, and delves into the intricate interplay of seasonality with environmental influences such as viral infections and solar radiation. The present study raises essential questions regarding the timing of environmental influences and the factors contributing to the rising prevalence of ASD. Ultimately, it underscores the need for future epidemiological research to incorporate more extensive investigations of environmental risk factors and employ advanced statistical analyses. This comprehensive overview contributes to a deeper understanding of how seasonality factors may be linked to the occurrence of ASD and its increasing prevalence, recognizing the multifaceted and diverse nature of these interactions.
COMMUNICATION | doi:10.20944/preprints202310.1266.v1
Subject: Physical Sciences, Other Keywords: DLA; Dielectric Laser Accelerator; Dual Grating; Single Drive
Online: 19 October 2023 (11:04:53 CEST)
Although hundreds of keV in energy gain have already been demonstrated in dielectric laser accelerators (DLAs), there remains challenge in creating structures that can confine electrons for multiple millimeters. We focus here on dual gratings with single sided drive, which have experimentally demonstrated energy modulation numerous times. Using a FTDT simulation to find the fields within various DLA structures and correlating these results with particle tracking simulation, we look at the impact of teeth height and width, as well as gap and offset, on the performance of these structures. We find a tradeoff between electron throughput and acceleration, but that for any given grating geometry there is a gap and offset that will allow some charge acceleration. For our 780 nm laser wavelength, this results in a 1200 nm optimal gap size for most gratings.
ARTICLE | doi:10.20944/preprints202310.1259.v1
Subject: Physical Sciences, Other Keywords: political polarization; statistical physics approaches for social dynamics
Online: 19 October 2023 (10:21:43 CEST)
This article belongs in the emerging area of research seeking ways to depolarize societies in the short run (around events such elections) as well as in a sustainable fashion. We approach the depolarization process with a model of three homophilic groups (US Democrats, Republicans and Independents interacting in the context of upcoming federal elections). We expand a previous polarization model, which assumed that each individual interacts with all other individuals in its group with mean-field interactions. We add a depolarization field which is analogous to the Blume-Capel model’s crystal field. There are currently numerous depolarization efforts around the world, some of which act in ways similar to this depolarization field. We find that for low values of the depolarization field, the system continues to be polarized. When the depolarization field increases, the polarization decreases.
ARTICLE | doi:10.20944/preprints202310.1032.v1
Subject: Physical Sciences, Other Keywords: distributed feedback (DFB) semiconductor lasers; modulation bandwidth enhancement; detuned-loading effect; reconstruction-equivalent-chirp (REC) technique
Online: 17 October 2023 (08:04:07 CEST)
A novel high-speed directly modulated two-section distributed feedback (TS-DFB) semiconductor laser based on the detuned-loading effect is proposed and simulated. Grating structure is designed by reconstruction-equivalent-chirp (REC) technique. A π phase-shift is introduced into the reflection grating, which can provide a narrow-band reflection region with a sharp falling slope on both sides of the reflection spectrum, thus enhancing the detuned-loading effect. Owing to its unique dual-falling-edges structure the bandwidth can be improved even when the lasing wavelength shifts beyond the left falling edge due to thermal effect in actual test, in which condition the detuned-loading effect can be used twice, which greatly improves the yield. The modulation bandwidth is increased from 17.5 GHz for a single DFB laser to around 24 GHz when the lasing wavelength is located on the left falling edge of the TS-DFB laser based on detuned-loading effect, and can be increased to 22 GHz for the right side. An eight-channel laser array with precise wavelength spacing is investigated, with side mode suppression ratio (SMSR) > 36dB. Besides, TS-DFB lasers with uniform reflection grating are studied and simulated result shows that modulation characteristic is far inferior to the laser with a phase-shifted grating reflector.
ARTICLE | doi:10.20944/preprints202310.0477.v1
Subject: Physical Sciences, Other Keywords: field electron emission; DFT; Au (100); Fowler-Nordheim; laser field emission
Online: 10 October 2023 (03:20:46 CEST)
Field electron emission, or electron tunneling through a potential barrier under the influence of a strong electrostatic field, is of broad interest to the accelerator physics community. For example, it is the source of undesirable dark currents in resonant cavities, providing a limit to high-field operation. The classical approach to field electron emission is the Fowler-Nordheim (FN) framework, which incorporates a simplified surface potential and various assumptions. Here we build a more realistic model using the potential and charge densities derived from a density-functional theory (DFT) calculation. We examine the correction factors associated with each model assumption. Compared to the FN framework, our results can be extended up to 80 GV/m, a limit that has been reached in laser-induced strong field emission scenarios.
ARTICLE | doi:10.20944/preprints202310.0388.v1
Subject: Physical Sciences, Other Keywords: Motion; Equation of motion; Irreversibility of motion; Time-inverse motion; Reverse motion; Two-particle collision; Detailed balance
Online: 9 October 2023 (10:54:31 CEST)
People have long had a problem: the equations of motion that reflect the laws of physics are invariance under time inversion, while there always are irreversible processes for gases compose of microscopic particles. This article solves this problem. The point is that we should distinguish between the concepts of the equation of motion and motion. We also need to distinguish between the concepts of time-inverse motion and reverse motion. The former is anticlockwise, which is a frictional motion, while the latter is clockwise. For the single-particle motions in classical mechanics and in quantum mechanics, we present mathematical expressions for time-inversion motion and reverse motion, respectively. We demonstrate that single-particle motion is irreversible. The definition of the reversibility of two-particle collisions is given. According to the definition, the two-particle collision as a microscopic motion processes is irreversible. Consequently, for a gas consisting of a large number of particles colliding with each other, its movement should be irreversible, unless the condition of detailed balance is met. We give a physical explanation for the detailed balance, which does not concern the meaning of microscopic reversibility. The detailed balance means that after a pair of reciprocal collisions occur, the distribution function of the particles remains unchanged. Therefore, microscopic two-particle collision events are irreversible, but the statistical average of a large number of collision events makes it possible for the macroscopic process of a gas to be reversible. Conclusively, we clarify the microscopic mechanism of the irreversible process of gases.
ARTICLE | doi:10.20944/preprints202309.2011.v1
Subject: Physical Sciences, Other Keywords: Burundi; Wind farm site selection; multi-criteria decision-making (MCDM); Fuzzy AHP logic tool; GIS
Online: 5 October 2023 (02:53:18 CEST)
The electricity generated from fossil fuel and nuclear energy has negative impacts on the environment and has shown a need to search for and promote the use of clean, renewable and sustainable energy resources such as wind, solar and geothermal resources. Nowadays, wind energy resource has emerged as the fastest-growing source of energy on an overall scale. However, the selection of the best location for constructing a wind farm is a vital issue that can be considered a site selection problem, which involves various conflicting factors. Therefore, it is classified as a multi-criteria decision-making (MCDM) problem. In this research, the site selection of wind power plants is conducted in Burundi country. The Fuzzy Analytic Hierarchy Process (FAHP) was used to weigh the criteria considering their relative importance. The main factors affecting optimal wind farm location considered in this study are wind speed, slope, distance from the grid network, distance to roads, and land use/land cover (LULC). Furthermore, a geographic information system (GIS) is utilized to generate the final suitability wind farm locations map. The obtained results show that 20.91% of the total study area is suitable; nevertheless, only 1.96% is highly suitable for wind farm placement. The western part of Burundi is concluded to be the most suitable area for wind farm construction and the most area is situated in Lake Tanganyika.
ARTICLE | doi:10.20944/preprints202309.1254.v1
Subject: Physical Sciences, Other Keywords: GPR; Depth Resolutions; 500Mhz GPR Antenna; MALA GPR equipment; 500MHz shielded Antenna; subsurface; Materials; GPR Survey
Online: 19 September 2023 (08:22:21 CEST)
This research work was aimed at investigating and determining the depth resolution of a 500Mhz GPR Antenna. The survey was conducted in an open space at the Physics Department, College of science-KNUST. The MALA GPR equipment with 500MHz shielded Antenna in the common offset-mode was used to investigate the depth at which materials were buried. Concrete block, tree roots, plastic bottle with water, glass bottle and Electric wire were each buried in cavities with five different burial depths. The real depth of each material was measured both along and across the cavity and compared to their corresponding GPR measured depth. The comparison of the Real depth and the GPR depth showed almost identical depth measurements with a root mean square deviation of 0.028m. The implication of this is that the 500 Mhz GPR antenna can accurately locate and detect the position of buried materials in the subsurface at a depth within the range (0.20-0.66) m.
ARTICLE | doi:10.20944/preprints202309.0995.v1
Subject: Physical Sciences, Other Keywords: attosecond electron bunches; ionization injection; two-color ionization injection; Resonant multi-pulse ionization injection; trojan horse
Online: 14 September 2023 (11:44:59 CEST)
High-quality ionization injection methods for Wake Field Acceleration driven by lasers or charged beams (LWFA/PWFA) can be optimised so as to generate high-brightness electron beams with tuneable duration in the attosecond range. We present a model of the minimum bunch duration obtainable with low-emittance ionization injection schemes, by spotting the roles of the ionization pulse duration, of the wake field longitudinal shape and of the delay of the ionization pulse position with respect to the node of the accelerating field. The model is tested for the resonant multi-pulse ionization injection (ReMPI) scheme, showing that bunches having length of about 300as can be obtained with a ionization pulse having duration of 30fs FWHM
ARTICLE | doi:10.20944/preprints202309.0082.v1
Subject: Physical Sciences, Other Keywords: CO2; CH4; CO; Bivariate polar diagram; weather conditions; Lamto; Côte d’Ivoire
Online: 5 September 2023 (10:26:05 CEST)
CO2, CH4 and CO are the most critical atmospheric gases in terms of their impact on the radiative system, air quality and health. This work provides information on the direction of source areas and potential sources of emissions and shows many aspects of these gases by a statistical analysis using bivariate polar diagrams and local weather conditions (e.g., temperature, wind speed and wind direction) recorded at the Lamto station (LTO, 6°31N and 5°02W) in Côte d’Ivoire over the 2014-2018 period. The results show that the main regions contributing to the high concentrations of CH4 (> 1925 ppb) and CO2 (> 420 ppm) in the GSS, GSP, PSS and PSP seasons are the North and Northwest sectors of Lamto. In these directions, CH4 and CO2 concentrations are associated with wind speeds less than 6 m.s-1, due to the influences of local sources as emissions resulting from the degradation of organic matter submerged during the impoundment of the Taabo dam, and/nor human activities linked to the practice of intensive agriculture. In addition, the high concentrations of CO (> 350 ppb) are observed in GSS in the North, North-West, North-East and East sectors for wind speeds less than or equal to 9 m.s-1, due to the influences of both local and distant sources. The correlation coefficients between CH4 and CO, and between CH4 and CO2 are positive and significant in all sectors. However, those calculated between CO2 and CO have showed both low and high values in all seasons.
ARTICLE | doi:10.20944/preprints202308.1880.v1
Subject: Physical Sciences, Other Keywords: unmanned aerial vehicle (UAV); microwave absorber; reduced graphene oxide
Online: 29 August 2023 (03:44:44 CEST)
In the work the enhanced security of unmanned aerial vehicles (UAVs) electronics in RF environment was investigated. UAVs are commonly used in many areas and the cellular networks as the parallel helping networks for systems: LTE, 5G or especially for future 6G are very perspective and needed. For effective communications in channels: “air-to-ground” as well as “drone-to-drone” the important task is undisturbed work of transportation platforms, ie. UAV. However, high level of outside electromagnetic radiation can affect the correct electronics work. The problem is due to non-conformity of RF environment regulations. The electromagnetic compatibility (EMC) standards guarantee correct electronics work when the radiation level is not higher than established EMC levels. In case of commercially available devices, like UAVs, this level is 3 V/m. On the other hand, permissive exposure level, treated as RF environment emitted by cellular base stations, can reach the level of 61 V/m. Such level of electromagnetic wave pollution, can damage unprotected electronics with fatal consequences. This can cause the unchecked drone flight or unchecked fall down. As a result, due to unchecked flight, the UAV can cause the sudden communication interruption with operator or other drones. To reduce the level of damaging RF field we propose to cover the UAV housing with microwave absorber. In this case absorber must ensure good electromagnetic protection as well as lightweight and resistant on weather conditions. The shielding property of reduced graphene oxide (RGO) as an absorber was investigated. For proposed material the shielding effectiveness (SE) was investigated in the frequency range from 100 MHz to 10 GHz. It has been proved that such material can be a good candidate as an absorber for UAV having low reflection coefficient and high absorption ability. In this work the shielding effectiveness of RGO was analyzed for two layers of 3 and 5 mm at typical frequencies as RF environment, ie. 3.6 GHz (5G system) and 5.8 GHz (LTE). Investigated absorber guarantees the value of SE of 25 dB and 30 dB for 3 mm layer at 3.6 GHz and 5.8 GHz respectively and of 29 dB and 39.5 dB for 5 mm layer at these frequencies respectively.
ARTICLE | doi:10.20944/preprints202308.1519.v1
Subject: Physical Sciences, Other Keywords: G-Brownian motion; exponential and LG2 estimates; boundedness; Convergence
Online: 22 August 2023 (07:24:21 CEST)
Generally, stochastic functional differential equations (SFDEs) pose a challenge as they often lack explicit exact solutions. Consequently, it becomes necessary to seek certain favorable conditions under which numerical solutions can converge towards the exact solutions. This article aims to delve into the convergence analysis of solutions for stochastic functional differential equations by employing the framework of G-Brownian motion. To establish the goal, we find a set of useful monotone type conditions and work within the space Cr((−∞,0];Rn). The investigation conducted in this article confirms the mean square boundedness of solutions. Furthermore, this study enables us to compute both LG2 and exponential estimates.
ARTICLE | doi:10.20944/preprints202308.1344.v1
Subject: Physical Sciences, Other Keywords: vibroimpact system; bifurcation; Chebyshev polynomial; uncertain parameter
Online: 18 August 2023 (11:32:37 CEST)
The inherent non-smoothness of vibroimpact system leads to complex behaviors as well as strong sensitive dependence on parameter changes. Unfortunately, uncertainties and errors in system parameters are inevitable in mechanical engineering. Therefore, the investigations of dynamical behaviors for vibroimpact systems with stochastic parameters are highly essential. The present study aims to analyze the dynamical characteristics of the three-degree-of-freedom vibroimpact system with an uncertain parameter by means of the Chebyshev polynomial approximation method. Specifically, the vibroimpact system model considered is one with unilateral constraint. Firstly, the three-degree-of-freedom vibroimpact system with an uncertain parameter is transformed into an equivalent deterministic form by the Chebyshev orthogonal approximation. Then, the ensemble means responses of the stochastic vibroimpact system are derived. Numerical simulations are performed to verify the effectiveness of the approximation method. Furthermore, the periodic and chaos motions under different system parameters are investigated, and the bifurcations of the vibroimpact system are analyzed by the Poincaré map. The results demonstrate that both the restitution coefficient and the random factor can induce the appearance of the periodic bifurcation. It is worth noting that the bifurcations fundamentally differ between the stochastic and deterministic systems. The former has a bifurcation interval, while the latter occurs at a critical point.
ARTICLE | doi:10.20944/preprints202308.0137.v2
Subject: Physical Sciences, Other Keywords: foundations of physics; chaos; block-universe; quantum-classical transition
Online: 18 August 2023 (11:23:32 CEST)
The following is undisputed: 1. The conceptual relation between QM, describing microscopic physics, and macroscopic irreversible physics, is as mysterious today as eighty years ago. 2. When propagating chaotic equations, arbitrarily small scales gradually become significant at arbitrarily large scales. It follows that, the long-time behavior of chaotic systems is as mysterious today as eighty years ago. Previous work by the author sheds new light on the quantum-classical riddle, suggesting that quantum weirdness is a signature of a non mechanistic ontology, viz., one not describable by some generalized state-vector plus evolution rule thereof. It is argued that neither an empirical nor a theoretical case exists against such non mechanistic ontology manifesting in certain macroscopic chaotic systems. Bell's inequality violation by separated but previously coupled such systems is one example. More radically, it is hypothesized that certain systems could fuzzily `remember their future' in the sense that, a future perturbation applied to them could be inferred from their present behavior with probability>0.5. Experiments utilizing machine learning are proposed for testing such hypotheses.
ARTICLE | doi:10.20944/preprints202308.0388.v1
Subject: Physical Sciences, Other Keywords: COVID-19; modified LDL; Z-scan; UV-visible spectroscopy; Lipoprint
Online: 4 August 2023 (11:03:56 CEST)
This study aimed to investigate the atherogenicity (quality) of LDL particles in patients with acute and recovered from COVID-19 infection. The participants were adults, aged 18 years or older of both sexes. Those with positive RT-PCR results at baseline were included in the Acute COVID-19 group (n=33), and those with negative RT-PCR six months after acute infection, were included in the Recovered COVID-19 group (n=30). The LDL quality was evaluated using three validated methods: Z-scan, UV-visible spectroscopy, and Lipoprint. The Recovered COVID-19 group showed significantly higher numbers of large LDL particles (less atherogenic) than the Acute COVID-19 group (P<0.05). We also found that COVID-19 infection was associated with the oxidative modification of LDL particles. D-dimer and CRP levels were correlated with Z-scan results and antioxidant-amount estimate. Moreover, we noticed that the infection left a sequel in LDL quality, even after six months of recovery. These findings highlight the importance of monitoring lipids during and after recovery from COVID-19 infection, and their potential deleterious effect on the LDL profile might correlate with the progression of atherosclerosis and poor clinical outcomes.
ARTICLE | doi:10.20944/preprints202307.1634.v1
Subject: Physical Sciences, Other Keywords: Symmetry; Nanoscale; Mean Square Deviation of Position; Quantum-Relativistic Effects; Analytical Modeling; Unification; Holism; Vacuum Energy.
Online: 25 July 2023 (08:11:10 CEST)
Analytical modeling has symmetries and aesthetic-mathematical characteristics that distinguish it from numerical computation. Nanoscience plays an extremely important role in unification efforts that also include holistic aspects of reality. In this paper I present new discovered results about the complete analytical quantum relativistic form of the mean square deviation of position false related to a lately appeared Drude-Lorentz-like model (DS model), already performed at classical, quantum and relativistic level. The function false gives precise information about the distance crossed by carriers (electrons, ions, etc.) inside a nanostructure, considering both quantum effects and relativistic velocities. The model has a wide scale range of applicability; the nanoscale is considered in this paper, but it holds from sub-pico-level to macro-level because of the existence of a gauge factor, making it applicable to every oscillating processes in Nature. Examples of application and suggestions supplement the paper, as well as interesting developments to be studied related to the model and to one of the basic elements of a current unified holistic approach based on the vacuum energy.
ARTICLE | doi:10.20944/preprints202307.1301.v1
Online: 19 July 2023 (07:20:01 CEST)
This article studies a class of pursuit problems admitting both a simple geometric solution as well as a more general analytic treatment. The results are specialized to demonstrate solutions to certain elementary problems typically posed to high schoolers, although a full analytic treatment, requiring some more comfort with geometry and calculus, is typically avoided at that stage.
ARTICLE | doi:10.20944/preprints202307.0877.v1
Subject: Physical Sciences, Other Keywords: Ouroboros Model; Analogical Algorithms; AI-Challenge; Large Language Models; Cybernetics; Synergetics; Understanding; Common Sense; Consciousness; Free Will.
Online: 13 July 2023 (12:28:07 CEST)
A topical challenge for algorithms in general and for automatic image categorization and generation in particular is presented with the aim of highlighting strengths and deficiencies of current Artificial Intelligence approaches while sketching a way forward. A general lack of encompassing symbol-embedding and (not only) -grounding in some bodily basis is made responsible for current deficiencies. A concomitant dearth of hierarchical organization of concepts follows suite. As a remedy for these shortcomings, it is proposed to take a wide step back and to newly incorporate aspects of cybernetics and analog control processes. It is claimed that a promising overarching perspective is provided by the Ouroboros Model with a valid and versatile algorithmic backbone for general cognition at all accessible levels of abstraction and capabilities.
ARTICLE | doi:10.20944/preprints202307.0474.v1
Subject: Physical Sciences, Other Keywords: Sociophysics; Stochastic Models; Galam’s Diffusion Model; Mathematical Programming; Parameter Optimisation
Online: 7 July 2023 (10:38:58 CEST)
The focus of this paper is on analyzing the role and the choice of parameters in sociophysics diffusion models, by leveraging the potentialities of sociophysics from a mathematical programming perspective. We first present a generalised version of Galam’s opinion diffusion model (see, e.g. , ). For a given selection of the coefficients in our model, this proposal yields the original Galam’s model. The generalised model suggests guidelines for possible alternative selection of its parameters that allow to foster diffusion. Examples of the parameters selection process as steered by numerical optimisation, taking into account various objectives, are provided.
REVIEW | doi:10.20944/preprints202306.2108.v1
Online: 29 June 2023 (11:18:08 CEST)
Optical immunosensors are one of the most popular category of immunosensors with applications in many fields including diagnostics, environmental and food analysis. The latter field is of particular interest not only for the scientists but also for the regulatory authorities and the public since food is essential for life but can be also the source of many health problems. In this context, the current review aims to provide an overview of the different types of optical immunosensors focusing onto their application for the determination of pathogenic bacteria in food samples. In particular, after the description of main optical transduction techniques, their implementation for the immunochemical determination of bacteria will be discussed. Finally, a short commentary about the future trends in optical immunosensors for food safety applications will be provided.
ARTICLE | doi:10.20944/preprints202306.0823.v1
Subject: Physical Sciences, Other Keywords: white noises; probability distributions; fractional calculus; colours of noise; classification of noises; kurtosis; codifference
Online: 12 June 2023 (10:22:50 CEST)
White noise is fundamentally linked to many processes, it has a flat power spectral density and a delta-correlated autocorrelation. Operators acting on white noise can result in coloured noise, whether they operate in the time domain, like fractional calculus, or in the frequency domain, like spectral processing. We investigate whether any of the white noise properties remain in the coloured noises produced by the action of an operator. For a coloured noise, which drives a physical system, we provide evidence to pinpoint the mother process from which it came. We demonstrate the existence of two indices, that is, kurtosis and codifference, whose values can categorise coloured noises according to their mother process. Four different mother processes are used in this study: Gaussian, Laplace, Cauchy, and Uniform white noise distributions. The mother process determines the kurtosis value of the coloured noises that are produced. It maintains its value for Gaussian, never converges for Cauchy, and takes values for Laplace and Uniform that are within a range of its white noise value. In addition, the codifference function maintains its value for zero lag-time essentially constant around the value of the corresponding white noise.
ARTICLE | doi:10.20944/preprints202306.0536.v1
Subject: Physical Sciences, Other Keywords: Fluid conveying carbon nanotubes; Timoshenko beams; Small-scale effects; Magnetic flux; Non-local strain gradients
Online: 7 June 2023 (10:39:43 CEST)
In this work,the wave behaviour propagation of single-walled fluid conveying carbon nanotubes (SWCNT) under longitudinal magnetic fields and elastic foundations is studied, based on the nonlocal strain gradients theory(NSGT). With considertion of surface effect, the governing differential equation are obtained utilising Timoshenko beam theory and Hamilton's variational principle. The influence of small-scale parameters, fluid density, magnetic flux, surrounding elastic medium and surface effects on wave behaviour characteristics of carbon nanotubes are discussed in detail. The numerical results illustrated that with the magnetic flux increase，the phase velocities of the carbon nanotube will increase. When the fluid effects inside the carbon nanotube, the wave frequencies of the system reduces with increase in the non-local coefficient, while promotes with increase in the strain gradient coefficient. In addition, fluid density, surrounding elastic medium and surface effects have meaningful influence on the phase velocity of the system.
ARTICLE | doi:10.20944/preprints202305.1951.v1
Subject: Physical Sciences, Other Keywords: neutrophil; exhaustive exercise; inflammation; cytokines; reactive oxygen species; acute kidney injury
Online: 29 May 2023 (03:07:44 CEST)
Prolonged exercise induces acute renal injury; however, the precise mechanism remains unclear. We investigated the effects of neutrophil depletion in male C57BL/6J mice. Male C57BL/6J mice were divided into four groups: sedentary with control antibody, sedentary with antineutrophil antibody, exhaustive exercise with control antibody, and exhaustive exercise with antineutrophil antibody. Antineutrophil (1A8) or control antibody was administered intraperitoneally to the mice prior to their running on a treadmill. Renal histology was assessed 24 h after exhaustive exercise, and the concentration of kidney injury molecule (KIM)-1 was measured using enzyme-linked immunosorbent assay. The expression levels of inflammatory cytokines were measured using quantitative reverse transcriptase-polymerase chain reaction. Furthermore, nicotinamide adenine dinucleotide phosphate oxidase activity and hydrogen peroxide concentration in the kidneys were measured. The pathologic changes were manifested as congested and swollen glomeruli, tubular dilatation, and nuclear infiltration after exhaustive exercise. These changes were suppressed by the administration of the 1A8 antibodies. KIM-1 concentration increased after exhaustive exercise but were reduced by the 1A8 antibodies. Treatment with the 1A8 antibody also decreased exhaustive exercise-induced inflammation and reactive oxygen species levels in the kidney. These results suggest that neutrophils contribute to exercise-induced acute renal injury by regulating inflammation and reactive oxygen species levels.
ARTICLE | doi:10.20944/preprints202305.1622.v1
Subject: Physical Sciences, Other Keywords: direction-of-arrival; sparse Bayesian learning; hierarchical Bayesian prior; sparse recovery
Online: 23 May 2023 (08:29:54 CEST)
Sparse direction-of-arrival (DOA) estimation of wideband signal has attracted widespread researches for its unique high-resolution performance. Numerous existing methods based on sparse Bayesian learning (SBL) don’t possess the ability to enhance sparsity even if they have already enjoyed high favor among sparse recovery approaches. In view of this, we propose a novel hierarchical Bayesian prior framework that enhance sparsity evidently and derive its corresponding iterative algorithm. On analysis, the computational complexity of the iterative are less than most existing other state-of-the-art algorithms. Not only that, proposed method possesses high angular estimation precision and sparsity performance by utilizing joint sparsity of multiple measure vector (MMV) models. Last but not least, the method obtains the ability to stabilize the estimated values between different frequencies or snapshots such that flat spatial spectrum. Extensive simulation results are presented to prove the superior performance of our methods
ARTICLE | doi:10.20944/preprints202304.1173.v1
Subject: Physical Sciences, Other Keywords: Zn-Al-Green Dyes Nanohybrids; PVA-Zn-Al-Dyes nanocomposite; UV–Vis absorption spectra; Band gap; Scanning electron microscopy; Thermal analyses
Online: 28 April 2023 (11:08:48 CEST)
In the present research, groups of nanolayered structures and nanohybrids based on organic green dyes and inorganic species are designated to act as fillers for PVA for inducing new optical sites and increasing its thermal stability through producing polymeric nanocomposites. In this trend, different percentages of Naphthol green B were intercalated as pillars inside the Zn-Al nanolayered structures to form green organic-inorganic nanohybrids. The two-dimensional green nanohybrids were identified by X-ray diffraction, TEM and SEM. According to the thermal analyses, the nanohybrid, which has the highest amount of green dyes, was used for modifying the PVA through two series. In the first series, three nanocomposites were prepared depending on the green nanohybrid as prepared. In the second series, the yellow nanohybrid, which was produced from the green nanohybrid by thermal treatment, was used to produce another three nanocomposites. The optical properties revealed that the polymeric nanocomposites depending on green nanohybrids became optical-active in UV and visible regions because the energy band gap decreased to be 2.2 eV. In addition, the energy band gap of the nanocomposites depended on yellow nanohybrids was 2.5 eV. The thermal analyses indicated that the polymeric nanocomposites are thermally more stable than that of the original PVA. Finally, the dual functionality of organic-inorganic nanohybrids that produced from the confinement of organic dyes and the thermal stability of inorganic species converted the non-optical PVA to optical-active polymer in a wide range with high thermal stability
ARTICLE | doi:10.20944/preprints202304.0818.v1
Subject: Physical Sciences, Other Keywords: dynamic phase transition; alternating magnetic field; magnetic nanoparticle; hyperthermia; specific loss power
Online: 24 April 2023 (04:16:54 CEST)
Magnetic nanoparticles (MNPs) have attracted a great interest in nanomedical research. MNPs exhibit many important properties, particularly, magnetic hyperthermia for selective killing of cancer cells is one of them. In hyperthermia treatment, MNPs act as nano-heaters when they are under the influence of an alternating magnetic field (AMF). In this work, micromagnetic simulations have been used to investigate the magnetization dynamics of a single-domain nanoparticle of magnetite in an external AMF. Special attention is paid to the circumstances dealing with a dynamic phase transition (DPT). Besides, we focus on the influence of the orientation of the magnetic easy-axis of the MNP on the dynamic magnetic properties. For amplitudes of the external AMF above certain critical value, the system is not able to follow the magnetic field and it is found in a dynamically ordered phase; whereas for larger amplitudes, the state corresponds to a dynamically disordered phase and the magnetization follows the external AMF. Our results suggest that the way how the order-disorder DPT takes place, and both the metastable lifetime as well as the specific loss power (SLP), are strongly dependent on the interplay between the orientation of the magnetic easy-axis and the amplitude of the external AMF.
ARTICLE | doi:10.20944/preprints202304.0752.v1
Subject: Physical Sciences, Other Keywords: Non-Gaussian time series; MRW; Bohmian quantum; Stock market
Online: 23 April 2023 (03:48:53 CEST)
We have implemented quantum modeling mainly based on Bohmian Mechanics to study time series that contain strong coupling between their events. Compared to time series with normal densities, such time series are associated with rare events. Hence, employing Gaussian statistics drastically underestimates the occurrence of their rare events. The central objective of this study is to investigate the effects of rare events in the probability densities of time series from the point of view of quantum measurements. For this purpose, we first model the non-Gaussian behavior of time series using the multifractal random walk (MRW) approach. Then, we examine the role of the key parameter of MRW, λ, which controls the degree of non-Gaussianity, in quantum potentials derived for time series. Our Bohmian quantum analysis shows that the derived potential takes some negative values in high frequencies (its mean values), then substantially increases, and the value drops again for rare events. Thus, rare events can generate a potential barrier in the high-frequency region of the quantum potential, and the effect of such a barrier becomes prominent when the system transverses it. Finally, as an example of applying quantum potential beyond the microscopic world, we compute quantum potentials for the S&P financial market time series to verify the presence of rare events in the non-Gaussian densities and demonstrate deviation from the Gaussian case.
ARTICLE | doi:10.20944/preprints202304.0490.v1
Online: 18 April 2023 (05:13:26 CEST)
This paper presents a simple model and explanation for the flat rotation curves of Spiral Galaxies without resorting to: (1) The introduction of Dark Matter, (2) a modification of Newton's 2nd law (MOND) or (3) a modification of Einstein's theory of General Relativity. The model that is developed involves a rotating baryonic disk (a rotating frame of reference with an "effective angular velocity" about its center surrounded by a rotating cloud of hydrogen (HI). The model also assumes that the measurements that are made on the rotating HI cloud are made from an earth based inertial frame of reference. The predictions of the model rely on the relationship between velocities as measured by earth based radio telescopes and the velocities as measured in the rotating frame. Calculations of the rotation curves of three galaxies are made using this model and compared with readily available experimental data
ARTICLE | doi:10.20944/preprints202303.0503.v1
Subject: Physical Sciences, Other Keywords: dynamical systems; self-organization; temporal periodicity; attractor topology; phase transitions; synchronization patterns; physical vacuum; elementary particles; unification of forces
Online: 29 March 2023 (07:08:35 CEST)
The phenomenon of dissipative self-organization is studied on the example of time-crystal networks. Particular attention was given to transient processes, attractor topologies, phase transitions, and asymptotic stability. New concepts were introduced, including topological phases, spinorial states, and bond flavors. Concepts such as ground states, chemical potentials, elastic forces, temperature, and statistical distributions were endowed with a new meaning associated with asymptotic stability. Phenomena usually attributed exclusively to quantum physics have been shown to occur in this essentially classical environment. They coexist with, and in some cases, such as charge quantization, are related to the phenomenon of time dilation. The approach was applied to model vacuum self-organization. We have shown that under the ac-tion of competing forces, such as gravity and antigravity, a cascade of phase transitions can transform an unorganized vacuum into phases in which interactions, fields and waves resemble electromagnetic, weak, and strong, and their elements can be used as building blocks for prototype particles. In addition, some interrelation field parameters and probabilities of particle transmutations were calculated, which are not predicted by the standard model. The results are consistent with the experiment. The presented material and methodology may be of interest for studying self-organization in different environments.
ARTICLE | doi:10.20944/preprints202303.0471.v1
Subject: Physical Sciences, Other Keywords: Foam; Node; Film; Marangoni flow; Plateau Border; Bubble; Reflux; Foam fractionation
Online: 28 March 2023 (03:54:44 CEST)
Marangoni flow in foam fractionation in the lamellar film for the interior and exterior of a micro-foam was investigated. The three-dimensional node-film-Plateau Border system was modeled using computational fluid dynamics. The importance of the surfactant concentration of the foam fractionation column and air-liquid interface mobility on the Marangoni velocity in the film was emphasized. The study found that an increase in surfactant concentration in the reflux column significantly increases the Marangoni velocities. Additionally, a mobile interface results in a higher Marangoni flow, while a rigid interface leads to less intensive flow. The behavior of the Marangoni flow in both interior and exterior foam was explored, revealing that the flow in exterior foam has different behavior due to the presence of the wall, which reduces the Marangoni velocity compared to interior films.
ARTICLE | doi:10.20944/preprints202301.0289.v1
Subject: Physical Sciences, Other Keywords: Measurement problem; Convivial Solipsism; Everett’s interpretation; QBism; Perspectival interpretation; Realism; Entanglement; Non-locality; EPR experiment; First person point of view; Wigner’s friend
Online: 17 January 2023 (01:32:40 CET)
I show how the quantum paradoxes occurring when we adopt a standard realist framework (or a framework in which the collapse implies a physical change of the state of the system) vanish if we abandon the idea that a measurement is related (directly or indirectly) to a physical change of state. In Convivial Solipsism, similarly to Everett’s interpretation, there is no collapse of the wave function. But contrary to Everett’s interpretation, there is only one world. This allows also to get rid of any non-locality and to provide a solution to the Wigner’s friend problem and its more recent versions.
ARTICLE | doi:10.20944/preprints202210.0419.v2
Subject: Physical Sciences, Other Keywords: Swarm dynamics; Criticality; Ising Model; Collective behavior
Online: 7 November 2022 (02:40:22 CET)
Social insects, such as honey bees exhibit complex behavioral patterns and their inconspicuous coordination enables decision-making on the colony level. It is thus proposed, that a high-level description of their collective behavior might share commonalities with neural processes in the brains. At the same time, recent research concerning overarching features of neural activity implies that brains are poised at the edge of the critical phase transition and that such a state is enabling maximal computational power and adaptability. In our research, we applied some tools developed in the computational neuroscience field to the dataset of bee trajectories recorded within the hive, during the course of many days. Our results imply that certain characteristics of the system are remarkably similar to the Ising model when it operates at critical temperature and also shares some of the features with the human brain at the resting state
ARTICLE | doi:10.20944/preprints202207.0382.v1
Subject: Physical Sciences, Other Keywords: opinion dynamics; bounded confidence; higher-order interaction; HK model
Online: 26 July 2022 (03:49:08 CEST)
The higher-order interactions in complex systems are gaining attention. Extending the classic bounded confidence model where an agent’s opinion update is the average opinion of its peers, this paper proposes a higher-order version of the bounded confidence model. Each agent organizes a group opinion discussion among its peers. Then, the discussion’s result influences all participants’ opinions. Since an agent is also the peer of its peers, the agent actually participates in multiple group discussions. We assume the agent’s opinion update is the average over multiple group discussions. The opinion dynamics rules can be arbitrary in each discussion. In this work, we experiment with two discussion rules: centralized and decentralized. We show that the centralized rule is equivalent to the classic bounded confidence model. The decentralized rule, however, can promote opinion consensus. In need of modeling specific real-life scenarios, the higher-order bounded confidence is convenient to combine with other higher-order dynamics, from the contagion process to evolutionary dynamics.
ARTICLE | doi:10.20944/preprints202206.0332.v1
Subject: Physical Sciences, Other Keywords: Innovation in teaching; Electromagnetic induction; High school students; Qualitative methods
Online: 24 June 2022 (07:43:23 CEST)
We present here a five hours experimentation of a didactical path about the electromagnetic induction addressed to students of the last year of an Italian scientific high school and oriented to better understand the physical origin of the induced electromotive force. The expression of the induced electromotive force as the sum of the term linked to the time variation of the magnetic field and of the motional one has been obtained in a detailed way, still suitable for presentation at high school. Many examples have been proposed to the students in order to clarify the conceptual physical knots. The students’ responses to a 6-questions multiple choice questionnaire have been analyzed. It emerged that our approach is concretely feasible although we find the well-known difficulties in calculating flux and circulation of a vector field. Furthermore, it emerged that an integral approach to the problem masks the understanding of the nature of the forces acting locally on the charges. Hence our proposal of a “redefinition” of the induced electric field in terms of the magnetic vector potential is also presented.
ARTICLE | doi:10.20944/preprints202103.0368.v1
Subject: Physical Sciences, Other Keywords: Contact; Rough Surfaces; Elastic-Perfectly Plastic Solid
Online: 15 March 2021 (11:26:47 CET)
In this paper, an incremental eqivalent contact model is developed for elastic-perfectly plastic solids with rough surfaces. The contact of rough surface is modeled by the accumulation of circular contacts with varying radius, which is estimated from the geometrical contact area and the number of contact patches. For three typical rough surfaces with various mechanical properties, the present model gives accurate predictions of the load-area relation, which are verified by direct finite element simulations. An approximately linear load-area relation is observed for elastic-plastic contact up to a large contact fraction of 15%, and the influence of yield stress is addressed.
ARTICLE | doi:10.20944/preprints202003.0178.v2
Subject: Physical Sciences, Other Keywords: consciousness; pre-reflective self-consciousness; physicalism; dynamism; causal productivity; meta-causation
Online: 29 March 2020 (11:56:10 CEST)
How, if at all, consciousness can be part of the physical universe remains a baffling problem. This article outlines a new, developing philosophical theory of how it could do so, and offers a preliminary mathematical formulation of a physical grounding for key aspects of the theory. Because the philosophical side has radical elements, so does the physical-theory side. The philosophical side is radical, first, in proposing that the productivity or dynamism in the universe that many believe to be responsible for its systematic regularities is actually itself a physical constituent of the universe, along with more familiar entities. It also proposes that instances of dynamism can themselves take part in physical interactions with other entities, this interaction then being “meta-dynamism” (a type of metacausation). Secondly, the theory is radical, and unique, in arguing that consciousness is necessarily partly constituted of meta-dynamic auto-sensitivity, in other words it must react via meta-dynamism to its own dynamism, and also in conjecturing that some specific form of this sensitivity is sufficient for and indeed constitutive of consciousness. This leads to a proposal for how physical laws could be modified to accommodate meta-dynamism, via the radical step of including elements that explicitly refer to dynamism itself.
ARTICLE | doi:10.20944/preprints201808.0299.v1
Subject: Physical Sciences, Other Keywords: chromatic polynomial; chromatically equivalent; chromatically unique; necklace graph
Online: 17 August 2018 (11:24:33 CEST)
For a graph G, let P(G, λ) be its chromatic polynomial. Two graphs G and H are said to be chromatically equivalent if P(G,λ) = P(H,λ). A graph is said to be chromatically unique if no other graph shares its chromatic polynomial. In this paper, chromatic polynomial of the necklace graph Nn, for n ≥ 2 has been determined. It is further shown that N3 is chromatically unique.