Penetration Factor Research Articles

Evaluation of static bending caused damage of glass-fiber composite structure using terahertz inspection

Abstract Composite materials find increasing applications in modern industry and transport. However, they may lose desirable mechanical properties due to external mechanical excitations, ultraviolet radiation, moisture penetration, or other factors. Therefore, an effective way to assess the condition of materials is necessary. In this article, a nondestructive evaluation of glass fiber-reinforced composite subjected to five-stage static bending is presented. For this reason, pulsed excitation terahertz imaging was utilized, and a data processing/exploration scheme was proposed. The proposed, novel approach consists of an efficient data registration algorithm based on surface approximation (for surface roughness and unevenness elimination) and a parametrization scheme applied for the signals gained from the time response of the glass fiber-reinforced polymer layer. Obtained parameters enable the global description of the evaluated material state and prediction of failure effectively, even in the early stages of destruction.

A study of the fine-structure constant dependence of radiative capture in Halo-EFT

We study the fine structure constant dependence of the rates of some selected radiative capture reactions within the framework of so-called Halo Effective Field Theory in order to assess the adequacy of some assumptions made on the Coulomb penetrability. We find that this dependence deviates from that implied by a parameterization of the cross sections of this effect via a simple penetration factor. Some features of this fine-structure dependence are discussed, in particular its potential impact on the abundances of the light elements in primordial nucleosynthesis.

Advancing superconductivity research: Insights from numerical simulations of potassium fullerenide-60 and gold and with Ginzburg-Landau theory

There are many types of superconductors, including gold ormus and some fullerene derivatives. Gold can become a superconductor at extremely low temperatures (<1 K), allowing it to conduct electricity without resistance. While not as commonly used as materials like niobium or lead, gold superconductors are valuable for research and development in superconductivity. Fullerene derivatives like potassium fullerenide-60 also exhibit high superconductivity. Limited studies have been conducted on both gold ormus and superconducting fullerene derivatives. Our study of numerical simulations of the Ginzburg-Landau theory in superconductors for gold ormus and potassium fullerenide-60 has yielded important results. We have successfully simulated class-I and class-II superconducting gold ormus, as well as potassium fullerenide-60, using the Runge-Kutta fourth order method. Our analysis demonstrates the convergence of our simulation outcomes and highlights the importance of considering truncation error and selecting appropriate step sizes for accurate results. The periodic factor of penetration (PFP) for each superconductor has been determined, with class-I superconducting gold having a PFP of 250 nm, class-II superconducting gold having a PFP of 566.2 nm, and potassium fullerenide-60 having a PFP of 1.374 nm. Additionally, our study reveals the relationship between the periodic penetration factor and the length of the penetration depth, showing that the PFP reaches a minimum value at a penetration depth length of 130 nm. Overall, our findings contribute to a better understanding of superconductivity in gold ormus and potassium fullerenide-60, emphasizing the importance of accurate numerical simulations for studying complex physical phenomena. Our study confirmed the accuracy of the Runge-Kutta fourth-order method in simulating superconductors. By examining the PFP for various superconducting materials, we identified trends in penetration depth, shedding light on superconductivity. Our simulations give valuable insights for advancing research in this field, with the Runge-Kutta fourth-order method striking a balance between accuracy and efficiency. Careful parameter adjustment ensures reliable simulations and contributes to progress in superconductivity research.

Robust fractional-order load frequency control for hybrid power system concerning high wind penetration

Hybrid power systems concerning wind farms have witnessed significant dynamic characteristic changes due to unpredicted generation output and integration mode conversion between frequency-sensitive wind plants and non-scheduled ones. This work presents a robust fractional-order load frequency control (LFC) method for a multi-area hybrid power system in the presence of wind penetration uncertainties. To characterize the injection effect of wind farms, the power system is described by a model with an uncertain wind penetration factor in a pre-estimated range. Then, an enhancement of Levy’s identification method is developed to convert this model into a fractional-order reduced structure to design the load frequency controller, which is in a form of fractional-order PID with a filter for ease of engineering implementation. The closed-loop stability is analyzed by the stability boundary locus (SBL) method under different wind penetration levels. It is shown that superior frequency response performance and system robustness can be obtained if the controller is designed in terms of the model with the worse-case wind penetration. Illustrative examples including a three-area hybrid power system under a variety of wind penetration variations are given to show the effectiveness of the proposed method.

Probing the Electric Field Response of a Water Molecule Confined in Small Carbon Nanocages: A Density Functional Theory Investigation.

We consider a water molecule under tight confinement in the small-sized fullerenes (C28, C30, C32) within the density functional theory (DFT) calculations with suitable exchange-correlation functionals. Such nanoscopic molecular cages provide an ideal setup to study their characteristic properties not present in the condensed phase. The water molecule entirely loses its feature of typical water when it is confined in small fullerenes of size equal to C30or smaller, in which the asymmetric O-H stretching vibration occurs at a lower wavenumber than the symmetric stretching. We study the response of the confined water molecule to the applied electric fields in terms of change in geometrical parameters, NMR spin-spin coupling constants, dipole moment, HOMO-LUMO (HL) gap, and vibrational frequency shift. The electric field shielding property of small-sized fullerene cages is explored and found to be strongly correlated with the HL gap. Since the electric field modulates the gap to decrease generally, shielding efficiency varies with field strength, thereby making large fields better shielded than small fields for the small penetration factor at large fields. The results that hold significance for technological applications are discussed.

The impact of policy and technology infrastructure on telehealth utilization.

The COVID-19 outbreak resulted in an unprecedented surge in telehealth utilization. However, the effects of policy enactment on utilization remain understudied in the literature. Our research examines the impact of policy mandates relating to federal incentive programs on telehealth utilization across states during the pandemic by considering technology infrastructure, such as broadband penetration and equipment possession. This study also considers the impact of political orientation and control factors, including income attributes, on telehealth utilization. Considering telehealth utilization in the Medicare program as a test case, this study employed the partial least square and structural equation model to analyze data from the Centers for Medicare & Medicaid Services, the American Community Survey, and the Microsoft Airband Project to draw inferences. Our study finds that telehealth legislation, broadband penetration, political orientation, and control factors have a direct significant impact on telehealth utilization, whereas incentive programs and equipment possession have an indirect impact through broadband penetration.

Interpretive modeling of tungsten divertor leakage during experiments with neon gas seeding

Many existing and future tokamaks with tungsten divertors operate, or will operate, with low-Z impurity seeding, but the direct effect of these seeded impurities on tungsten Scrape-off-Layer (SOL) transport has not been explored in detail. This paper reports on a DIII-D experiment designed to test how tungsten divertor leakage from the Small-Angle Slot V-Shaped, tungsten-coated divertor is impacted by neon seeding at a variety of injection rates and poloidal injection locations. Measurements from the experiment show an inverse relationship between the neon injection rate and the tungsten core penetration factor. Interpretive modeling is performed with a combination of the SOLPS-ITER and DIVIMP codes to assess the underlying tungsten behavior. The modeling results show that the reduction in tungsten divertor leakage is driven by both an increase in the divertor collisionality as well as a reduction in the ion temperature gradient near the divertor target. Collisions between low-Z impurities and tungsten impurities are found to have a significant impact on the tungsten SOL transport, such that ignoring the low-Z impurity collisional effects on the tungsten transport can result in an overestimate of the divertor leakage by an order-of-magnitude. Given the importance of these localized interactions, neon seeding from the closed, slot-like divertor has a clear advantage in being able to reduce tungsten divertor leakage without the high levels of neon core contamination that occur when seeding from other poloidal locations.

Whole-body distribution of tenofovir, emtricitabine and dolutegravir in non-human primates.

One major barrier to HIV cure is the persistence of virus, possibly linked to an insufficient antiretroviral drug (ARV) distribution into tissues. To draw the whole-body distribution of three antiretroviral drugs-tenofovir disoproxil fumarate, emtricitabine and dolutegravir-in non-human primates (NHPs). Eight uninfected NHPs received a single injection of a solution containing the three ARVs. Forty-five different tissues were sampled 24 h after injection. Median tissue penetration factors (TPFs) were 45.4, 5.8 and 0.5 for tenofovir, emtricitabine and dolutegravir, respectively, and were statistically different between the three ARVs. Tissues were grouped by system, because TPFs were consistent according to these groups, and ranked in order of decreasing TPFs. The digestive system was the system with the highest tissue concentrations. Next came the two main sites of elimination, the liver and the kidney, as well as the tissues of the cardiopulmonary and urinary systems. Then, it was the whole lymphatic system. The next group included the reproductive system, the adipose tissue and the skin. The last two systems were the muscle and the CNS. The intra-tissue variability was rather low with a median coefficient of variation of the concentrations around 15% and no value greater than 80%. Overall, this study determines the first whole-body distribution in a validated NHP model. These data have important implications for future preclinical and clinical studies for the development of novel HIV therapies towards an HIV cure.

Underluminous tidal disruption events

Abstract We have evidence of X-ray flares in several galaxies consistent with a a star being tidally disrupted by a supermassive black hole (MBH). If the star starts on a nearly parabolic orbit relative to the MBH, one can derive that the fallback rate follows a t−5/3 decay. Depending on the penetration factor, β, a star will be torn apart differently, and relativistic effects play a role. We have modified the standard version of the smoothed-particle hydrodynamics (SPH) code Gadget to include a relativistic treatment of the gravitational forces between the gas particles of a main-sequence (MS) star and a MBH. We include non-spinning post-Newtonian corrections to incorpore the periapsis shift and the spin-orbit coupling up to next-to-lowest order. We find that tidal disruptions around MBHs in the relativistic cases are underluminous for values starting at β≧2.25; i.e. the fallback curves produced in the relativistic cases are progressively lower compared to the Newtonian simulations as the penetration parameter increases. While the Newtonian cases display a total disruption, we find that all relativistic counterparts feature a survival core for penetration factors going to values as high as 12.05. We perform a additional dynamical numerical study which shows that the geodesics of the elements in the star converge at periapsis. We confirm these findings with an analytical study of the geodesic separation equation. The luminosity of TDEs must be lower than predicted theoretically due to the fact that the star will partially survive when relativistic effects are taken into account. A survival core should consistently emerge from any TDE with β≧2.25.

Multi-objective optimal sizing and design of renewable and diesel-based autonomous microgrids with hydrogen storage considering economic, environmental, and social uncertainties

The multifaceted nature of human society necessitates the consideration of various indicators when planning and designing energy systems. The success of energy systems is contingent on their ability to reliably meet demands while satisfying different objectives that align with societal needs. This paper presents the multi-objective optimal design and configuration of hydrogen-storage-based microgrids to reliably meet electric load demands in remote regions while considering economic, environmental and social uncertainties. A comprehensive Mixed Integer Linear Programming (MILP) was adopted to model the microgrid consisting of renewable energy systems (RES), hydrogen energy storage system (HESS), battery energy storage system (BESS), and diesel generator (DG). Advanced Interactive Multidimensional Modelling System (AIMMS) was used to perform the deterministic and robust optimisation with special consideration on cost-greenhouse emissions minisation and employment generation maximisation. This study further performs a comparative analysis between hydrogen-based microgrids and lithium-ion battery-based microgrids in terms of the key objectives. In overall performance, the configuration consisting of photovoltaic (PV), wind turbine (WT), fuel cell (FC), electrolyser (EL) and low-pressure tank (LPT) outplays the other configurations considered in terms of total job factor, levelised cost of electricity, renewable energy penetration factor, carbon emission reduction capability. Considering both deterministic and robust solutions of the configuration, the levelised cost of electricity ranges between 0.131 and 0.169 $/kWh, the total lifetime cost varies from $2,002,100 to $6,784,740, and the job provision factor ranges between 0.339 and 0.447. Nevertheless, there is a need for further reduction of the investment cost for its continued technological and market penetration. This is a good basis for the adoption of hydrogen-based storage systems with renewable energy systems.

Mechanistic indoor air quality model and data-driven calibration for intelligent HVAC AI control system through real-time data in underground buildings

Abstract Modeling the dynamics of indoor air quality (IAQ) in subway environments is challenging due to the complex interplay of variables like subway schedules, ventilation, and passenger numbers. This study developed a high-precision mechanistic model for IAQ management and intelligent HVAC control in underground buildings, focusing on Y-station. Global Sensitivity Analysis (GSA) highlighted the significance of the train piston factor during operational hours and the increased sensitivity of penetration and deposition factors when trains are not operational. The model, calibrated in real-time using a Genetic Algorithm (GA), exhibited remarkable accuracy in simulating PM2.5 levels, affirming its effectiveness in forecasting future air quality. The model adeptly captures the complexities of air quality dynamics, providing a comprehensive understanding of temporal IAQ variations. The result demonstrates the model’s efficacy as a tool offering a foundation for strategies to forecast IAQ and control the HVAC system in underground buildings.

Indoor concentrations of radioactive aerosols from nuclear accidents.

In previous studies, some of the important factors that affect the spread of radioactive aerosols into indoors were considered. The studies were based on a new CFD approach and provided good descriptions for the deposition of aerosol particles inside small spaces and the penetration of aerosols into buildings through wall cracks. In this article, an application of those studies is implemented, where all the graphical relations that are required to estimate the indoor concentrations of radioactive aerosols from nuclear accidents are provided. This includes the deposition velocities, deposition rate, and the penetration factor. Particular interest is in the Fukushima-Daiichi nuclear power plant accident that took place in Japan in 2011. The aerosols carrying the radioiodine iodine-131 and the radiocesium cesium-134 and cesium-137 are studied. Based on the model's assumptions, and assuming steady-state air concentrations, the radioactive aerosols' concentrations in indoor air are about 97% of the concentrations in outdoor air. The applications demonstrate the model to be convenient and practical.

Preclinical Pharmacokinetic Study and Lung Penetration of a Coumarin Extracted from Zanthoxylum tingoassuiba.

The compound 6-methoxyseselin, derived from Zanthoxylum tingoassuiba, demonstrates various therapeutic properties, including vasorelaxation, antinociceptive, anti-inflammatory, and immunomodulatory effects, along with recently discovered antiasthmatic properties. This study aimed to evaluate its preclinical pharmacokinetics and pulmonary delivery in Balb/c mice. The method involved administering the compound via inhalation and intravenous routes, followed by blood sample collection for analysis using high-performance liquid chromatography with diode array detection (HPLC-DAD). The results indicated good linearity, precision, accuracy, and stability of the compound in the biological samples. Pharmacokinetic parameters such as the rate of elimination, half-life, clearance, volume of distribution, area under the curve, and mean residence time were determined for both administration routes, showing similar profiles. The lung concentrations were notably higher than the plasma concentrations, indicating significant lung penetration. These findings suggest 6-methoxyseselin as a promising candidate for new anti-asthmatic drugs, supported by its favorable pharmacokinetic profiles and high lung penetration factors. This study represents the first exploration of the pharmacokinetics and pulmonary delivery of 6-methoxyseselin in mice, highlighting its potential for further drug development.

Resonant tunnelling of wave packet

This paper examines tunnelling through potential well protected by double barriers as well as the motion of a wave packet encountering this type of potential. Various options for the left and right barriers’ penetration factors are taken into consideration. When one of the penetration factors has limiting value of 0.5, the transmission coefficients turns out to be independent of incoming energy of the particle and the width of potential well. When both penetration factors have a limiting value of 0.5, a scenario similar to resonance tunneling is achieved. Furthermore, by doing the wave packet analysis, we found that the width and height of potential barriers have a negligible impact on the probability of finding the particle inside the potential well in the limit of large penetration factors.

Association of ITGA4 and ICAM-1 gene polymorphisms with the risk and clinicopathological characteristics of Crohn's disease

To assess the association between the polymorphism of integral protein α4 (ITGA4) and intercellular adhesion molecule 1 (ICAM-1) genes and the risk and clinicopathological characteristics of Crohn's disease (CD) among Chinese patients. From January 2010 to January 2021, a total of 215 CD patients and 529 gender- and age-matched healthy controls were enrolled from the Second Affiliated Hospital of Wenzhou Medical University as the study subjects. Genotypes of ITGA4 (rs6740847, rs7562325) and ICAM-1 (rs5498) were determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Harvey-Bradshaw Index (HBI) was applied to assess the disease activity of CD, and the patients were further divided into subgroups based on the Montreal Classification Criteria of CD. Unconditional logistic regression was employed to analyze the distribution of ITGA4 (rs6740847, rs7562325) and ICAM-1 (rs5498) polymorphisms between the patients and healthy controls and their association with the clinicopathological characteristics of the patients. The frequencies of T allele and CT+TT genotypes of ITGA4 (rs7562325) were higher in CD patients than the healthy controls (40.70% vs. 31.57%, P = 0.001; 62.79% vs. 54.36%, P = 0.042). The G variant and AG+GG genotypes of ITGA4 (rs6740847) were less common in patients with moderately to severely active CD compared with those with mildly active CD (31.18% vs. 51.72%, P = 0.002; 55.91% vs. 75.86%, P = 0.042). However, the opposite conclusion was drawn for the G allele (G) and AG+GG genotypes of ICAM-1 (rs5498) (31.45% vs. 17.24%, P = 0.027; 54.30% vs. 31.04%, P = 0.020). Compared with patients with terminal ileal or ileocolic CD, G allele and AG+GG genotypes of ITGA4 (rs6740847) were more prevalent in patients with colonic CD (55.26% vs. 29.38%, P < 0.001; 84.21% vs. 53.11%, P<0.001). The same conclusion could also be drawn for the G allele and AG+GG genotypes of ICAM-1 (rs5498) (42.11% vs. 26.84%, P = 0.008; 73.69% vs. 46.33%, P = 0.002). The frequency of homozygous GG genotype of ICAM-1 (rs5498) was lower in patients with stricturing and penetrating CD than those with non-stricturing and non-penetrating CD (0.00% vs. 12.32%, P = 0.001). The G allele and AG+GG genotypes of the ITGA4 (rs6740847) were more common in patients with perianal lesions than those without (40.28% vs. 30.77%, P = 0.049; 72.22% vs. 51.75%, P = 0.004). Variants of the ITGA4 (rs7562325) may be a risk factor for CD, whilst those of the ITGA4 (rs6740847) may be associated with the decline of disease activity and risk for colon involvement and perianal lesions. Variants of the ICAM-1 (rs5498) may increase the risk of disease activity and colonic involvement in CD patients, however, it may be a protective factor for stenosis and penetration. In addition, variants of the ITGA4 (rs6740847) and ICAM-1 (rs5498) may be associated with the early onset of CD.

“Tidal Peeling Events”: Low-eccentricity Tidal Disruption of a Star by a Stellar-mass Black Hole

Close encounters between stellar-mass black holes (BHs) and stars occur frequently in dense star clusters and in the disks of active galactic nuclei. Recent studies have shown that in highly eccentric close encounters, the star can be tidally disrupted by the BH in a microtidal disruption event (microTDE), resulting in rapid mass accretion and possibly bright electromagnetic signatures. Here we consider a scenario in which the star might approach the stellar-mass BH in a gradual, nearly circular inspiral, under the influence of dynamical friction in a circum-binary gas disk or three-body interactions in a star cluster. We perform hydrodynamics simulations of this scenario using the smoothed particle hydrodynamics code PHANTOM. We find that under certain circumstances (for initial eccentricity e 0 ≳ 0.4 and penetration factor β = 1, or e 0 < 0.4 and β ≲ 0.67), the mass of the star is slowly stripped away by the BH. We call this gradual tidal disruption a “tidal-peeling event.” Additionally, we discover that some low-eccentricity microTDEs (e 0 < 0.4 and β = 1) are a new form of fast luminous transients similar to parabolic microTDEs. Depending on the initial distance and eccentricity of the encounter, these low-eccentricity microTDEs might exhibit significant accretion rates and orbital evolution distinct from those of a typical (eccentric) microTDE.

Analysis of Influencing Factors of Pile Penetration of Jacket Platform Skirt Pile

Analysis of Influencing Factors of Pile Penetration of Jacket Platform Skirt Pile

R-MATRIX CALCULATIONS OF THE DEUTERIUM-TRITIUM FUSION CROSS SECTION BASED ON PRECISE COULOMB FUNCTIONS

Due to the availability of fuel, favorable kinetics, and high output energy, the deuterium-tritium (D-T) fusion reaction is dominantly used in thermonuclear fusion. This paper presents a detailed, step-by-step theoretical calculation of the D-T fusion cross-section within the framework of the phenomenological R-matrix method.The fundamental principles of the phenomenological R-matrix method are outlined.Nuclear and Coulomb interactions are addressed by the R-matrix formalism, which classifies the configuration space into internal and external regions, respectively.Precise Coulomb functions are utilized in the calculations, essential for the accurate determination of the penetration and shift factors.Precise Coulomb functions for the D+T,4He+12C systems have been calculated. The penetration and shift factors for the D+T system for a given angular momentum have been obtained.Two different R-matrix models with parameters from recent scientific papers are employed to calculate D-T fusion cross-sections and reaction rates, which are then compared with those obtained from the ENDF/B-VIII.0 library data. Within a crucial low-energy range (from 0 to 0.1 MeV), important for fusion technology, our results show quite good agreement with experimental data, while in a high-energy range, the obtained results are slightly underestimated due to non-resonant 5He levels not being taken into account. These findings indicate that the models can be used for future thermonuclear fusion applications.

Tidal Disruption Events through the Lens of the Cooling Envelope Model

The cooling envelope model for tidal disruption events (TDEs) postulates that while the stellar debris streams rapidly dissipate their bulk kinetic energy (“circularize”), this does not necessarily imply rapid feeding of the supermassive black hole (SMBH). The bound material instead forms a large pressure-supported envelope that powers optical/UV emission as it undergoes gradual Kelvin–Helmholtz contraction. We present results interpreting a sample of 15 optical TDEs within the cooling envelope model in order to constrain the SMBH mass M BH, stellar mass M ⋆, and orbital penetration factor β. The distributions of inferred properties from our sample broadly follow the theoretical expectations of loss-cone analysis assuming a standard stellar initial mass function. However, we find a deficit of events with M BH ≲ 5 × 105 and M ⋆ ≲ 0.5 M ⊙, which could result in part from the reduced detectability of TDEs with these properties. Our model fits also illustrate the predicted long delay between the optical light-curve peak and when the SMBH accretion rate reaches its maximum. The latter occurs only once the envelope contracts to the circularization radius on a timescale of months to years, consistent with delayed-rising X-ray and nonthermal radio flares seen in a growing number of TDEs.

Sperm DNA damage in men with severe asthenozoospermia

Background. Sperm motility is a fundamental factor for sperm penetration into the oocyte and fertilization. According to the World Health Organization (WHO) 2021, less than 42% of motility is called asthenozoospermia, which is one of the most common causes of male infertility. This retrospective cohort study aims to investigate sperm DNA damage with TUNEL and SCSA methods and its relationship with sperm parameters, age, and body mass index (BMI) in severe asthenospermia (&lt;2% sperm motility) and normozoospermia. Methods. The study parameters between 111 subjects with severe asthenozoospermia and 113 subjects with normozoospermia were investigated. The 2010 World Health Organization guidelines were used to evaluate sperm parameters, and TUNEL and SCSA methods were used to assess sperm DNA damage. The statistical analysis was done using the t-test of two independent samples. Pearson's correlation coefficient was used to investigate the relationship between sperm DNA damage and sperm parameters, age, and BMI P&lt;0.05 was considered significant. Results. The mean seminal volume, sperm concentration and count, and the percentage of sperm total motility and progressive motility were significantly lower in severe asthenospermic subjects compared to normozoospermic subjects (P&lt;0.001). In addition, the mean percentage of sperm DNA damage in severe asthenozoospermic individuals was significantly higher than in normozoospermic individuals (P&lt;0.001). There was also a positive and significant relationship between sperm DNA damage and the age of severely asthenozoospermic men. Conclusion. Sperm motility, sperm DNA damage, and the father's age are essential in the successful conception, development, and health of the embryo. Therefore, the evaluation of sperm DNA damage is recommended in examining male fertility and selecting the appropriate treatment approach for men with severe asthenozoospermia. Practical Implications. Considering that the sperm genome constitutes 50% of the genetic material of the next generation, evaluating sperm DNA health to determine the appropriate treatment approach in infertile men can be influential in the success of assisted reproductive techniques and in maintaining the next generation’s health.