Distribution Profiles Research Articles

Application of Finite Pointset Method to Study Two‐Way Coupled Transient Bio‐Thermoelastic Effects in Skin Tissue

ABSTRACTIn this research, we introduce the finite pointset method as an innovative approach for approximating transient linear thermoelasticity in biological tissue, addressing the complex interplay between thermal and elastic effects under three distinct shock conditions. Numerical simulations are performed to solve the coupled thermoelasticity equations, demonstrating the temperature distribution, displacement, and stress profiles within the tissue. The results highlight the influence of shock conditions on the thermal and mechanical responses of the tissue, emphasizing the impact of coupling parameter and perfusion rate. Numerical simulations are applied to several benchmark thermoelasticity problems, providing numerical results that validate the approach. Notably, our findings reveal the cooling effects induced by perfusion under both coupled and uncoupled scenarios and highlight the variability of temperature, displacement and stresses based on the coupling parameter. This work contributes to the field of biomedical engineering by providing insights into tissue behavior under thermal stress and offering potential applications in medical technology and therapeutic interventions. The use of FPM not only enhances the accuracy of modeling thermal and mechanical effects in biological tissues but also paves the way for advancements in medical technology. These findings have the potential to inform the development of new therapeutic strategies, particularly in areas related to laser treatments, thermal therapies, and other medical interventions requiring precise control of temperature and stress within tissues.

Impact of Short-Wave Solar Absorptivity on Jointed Plain Concrete Pavement Response

This study investigates the impact of the pavement’s short-wave solar absorptivity (SA) on the temperature profile and subsequent thermal-stress distribution through rigid pavement slabs. A one-dimensional heat transfer model is proposed to simulate the pavement temperature using a modified Blasius solution to estimate the heat convection coefficient at the pavement surface. In-service slab temperatures are used to verify the feasibility of the proposed model. It was found that an increase in SA amplifies both the magnitude and non-linearity of the temperature gradients in the slab, thus raising the linear bending stress and self-equilibrating stresses through the slab. Concrete surface materials must be properly characterized in order to accurately assess the thermal-induced stress development in concrete pavement structures and to better estimate the longevity of its service life.

Factors Related to Drug Abuse as Perceived by Maranao College Freshmen Students of Mindanao State University

This study aimed to investigate the perceptions of Maranao freshman college students at Mindanao State University (MSU) regarding drug abuse. It examined selected factors related to drug abuse, which serve as the baseline for formulating a training model for the guidance program. The study also explored the relationship between drug abuse and specific factors as perceived by the students. The study sought to answer the following questions: 1. What is the profile distribution of respondents in terms of sex, age, and civil status, knowledge of someone who is a drug user, number of drug users known, and their relation to the user? 2. What is the profile distribution of first-year college students regarding their perceptions of factors affecting drug abuse in terms of relief from problems, sense of security, curiosity, and "pakikisama"? or peer pressure. 3. What are the most common drugs used by drug abusers as perceived by the respondents? 4. Is there a significant relationship between drug abuse and the factors in terms of relief from problems, curiosity, "pakikisama" or sense of security, peer group influence, and pleasure? 5. What training model for a guidance program can be formulated from the findings of the study? The Maranao respondents were college freshmen students of Mindanao State University selected through random sampling. To gather the necessary data, a questionnaire was distributed, and the responses were analyzed using frequency and percentage computations.

Clinical Pharmacokinetics of N,N-Dimethyltryptamine (DMT): A Systematic Review and Post-hoc Analysis.

N,N-Dimethyltryptamine (DMT) is currently being studied for its therapeutic potential in various psychiatric disorders. An understanding of its pharmacokinetics (PK) is essential to determine appropriate dose ranges in future clinical studies. We conducted a systematic literature review on the PK of DMT. Clinical studies that administered known amounts of DMT and reported PK data and/or parameters in humans were included. Additionally, raw PK data were requested from authors and/or extracted from publications. In total, 219 references were retrieved, of which 13 publications were included, covering eight distinct datasets. All studies administered DMT intravenously in various infusion schemes, except for one intramuscular administration. High variability in dose-normalized exposure parameters and differences in exposure for bolus versus infusion administration were observed. DMT is extensively redistributed to other tissues, based on its biphasic elimination profile and high volume of distribution in the terminal elimination phase (range 123-1084 L). It is eliminated rapidly, with a half-life of 4.8-19.0 min and clearance of 8.1-46.8 L/min. This is a result of the rapid metabolization of DMT to indole-3-acetic acid (IAA), which is also reflected in the fact that the time of maximum concentration of IAA is similar to that of DMT. This review demonstrates that the PK of DMT in humans have been characterized to a limited extent, and publications lack details with regards to demographics, absolute doses, and PK parameters. Additional studies are necessary to investigate high intersubject variability and differences in exposure following bolus or prolonged infusion. Addressing these issues is essential for the development of DMT as a pharmacotherapeutic in neuropsychiatry.

Antimicrobial resistance pattern and species distribution profile of aerobic bacteria causing sterile body fluid infection from a tertiary care hospital

Objectives: Body fluids such as pleural fluid, ascitic fluid, and cerebrospinal fluid are sterile but they can get infected by different microorganisms leading to life-threatening infections. We conducted this study to evaluate the distribution profile of various aerobic bacteria and their antimicrobial resistance pattern isolated from sterile body fluids from the patients attending a tertiary care hospital in North India. Materials and Methods: This hospital-based cross-sectional observational study was conducted in the Department of Microbiology of a tertiary care hospital. A total of 495 sterile body fluid samples were processed for species-level identification of aerobic bacteria by conventional methods following standard laboratory procedures. The antimicrobial susceptibility testing was performed by Kirby–Bauer disc diffusion method according to clinical and laboratory standards institute guidelines 2020. Results: Out of a total of 495 sterile body fluid samples, 48 were found positive on culture for bacterial pathogens. The predominant organisms isolated from sterile body fluids were Acinetobacter species (35%), followed by Klebsiella species (23%), Escherichia coli (13%), Pseudomonas species (12%), Staphylococcus aureus (13%), and Streptococcus species (4%). All of the Gram-negative isolates were 100% sensitive to Colistin followed by amikacin (67.50%) and gentamicin (60%). The Gram-positive isolates were 100% sensitive to vancomycin and linezolid followed by gentamicin (50%). Conclusion: Infections of sterile body fluids can lead to high morbidity and mortality. The knowledge of the bacteriological and antimicrobial resistance profile of bacteria causing sterile body fluid infections is vital in determining appropriate antimicrobial therapy.

AI in the classroom: Exploring students’ interaction with ChatGPT in programming learning

Abstract As being more prevalent in educational settings, understanding the impact of artificial intelligence tools on student behaviors and interactions has become crucial. In this regard, this study investigates the dynamic interactions between students and ChatGPT in programming learning, focusing on how different instructional interventions influence their learning and AI-interaction. Conducted over three sessions, students were allowed to use ChatGPT to complete programming tasks. The first session had no guidance, the second included hands-on training in prompt writing and effective ChatGPT use, and the third provided a lab guide with sample prompts. After each session, students took a post-test on the activity’s subject. Analyzing students’ prompting behaviors, five AI interaction profiles were identified: AI-Reliant Code Generators, AI-Reliant Code Generator & Refiners, AI-Collaborative Coders, AI-Assisted Code Refiners, and AI-Independent Coders. These profiles were examined to understand their evolution across interventions and their relationship with students’ learning performance. Findings revealed significant changes in profile distribution across interventions, and a notable difference between students’ post-test scores and their AI interaction profiles. Besides, training in prompting skills and effective use of AI significantly impacted students’ interactions with AI. These insights can contribute to the knowledge of integrating generative AI tools in education, highlighting how AI can enhance teaching practices. Understanding student-AI interaction dynamics can allow educators to tailor instructional strategies for optimal learning. This study also underscores the importance of guidance on effective AI use and prompting skills, which can lead students to use AI more meaningfully for their learning.

Migración internacional y trabajo en México: un análisis contemporáneo

Migration, an undeniable driver for development according to the UN's Agenda 2030, plays a pivotal role in Mexico, serving as a point of origin, transit, and destination for migrants. This article presents a detailed analysis of international migration in Mexico with a focus on its impact on economic activity. Utilizing microdata from the National Occupation and Employment Survey (ENOE) for the third quarter of 2023, comprising a sample of 150,449 households, various aspects are explored, from migrants' origins to their sociodemographic profile and geographical distribution. Furthermore, an innovative methodology from CEPAL (2023) is employed to estimate the contribution to the Gross Domestic Product by migratory origin and sector of activity of international migrants in Mexico. This approach provides a deep and updated understanding of migration in Mexico, emphasizing its significance for the national economic dynamics and its role in shaping the country's labor and business landscape. The findings offer valuable insights for policy formulation and understanding the economic implications of migration.

Simultaneous vibration and soil moisture sensing using a single mode fiber for structural health monitoring applications

A dual-purpose single mode optical fiber sensor was developed for simultaneous soil moisture and structural health monitoring. Unmodified G655 SMF with polarization coupled phase components was used to detect environmental changes due to ground movement and moisture content variations. Spectral distribution profiles of the baseband frequencies below 10 Hz were analyzed for structural health monitoring, while resonant peak frequencies higher than 110 Hz had notable dependence on the damping effect of moisture on the spectral peak intensity of the detected acoustic waves. Using these peaks, moisture content was measured within a root mean square error value of +/−0.04. The sensor demonstrates a critical resource optimization tool for distributed sensing applications and monitoring in PON systems.

Polarization force driven FHD flow over a permeable disc with geothermal viscosity

In this paper, we investigate the Bödewadt boundary layer flow of ferrous oxide-based electrically non-conducting Nanofluid considering the influence of thermal radiation and viscous dissipation over a permeable disc with slip conditions. Here, viscosity is taken as a function of temperature and depth. The equation of energy incorporates the radiative heat flux as described by the Rosseland approximation. The Von Kármán Model alters the constitutive nonlinear coupled partial differential equations of motion, which include slip boundary conditions. The final system of equations in PDE is solved computationally using a shooting approach in MATLAB with ode45, and the results are elucidated, through graphs and tables. The effects of all the above-considered physical entities including the geothermal viscosity on the velocity profile and temperature distribution over the disc are examined. An exhaustive analysis of all the above-investigated results is presented for the record. It is observed that the geothermal viscosity with considered boundary conditions retards the motion of the fluid causing decay in the net molecular movement and the thermal diffusion.

The Study Analyzed Soil Samples from the Bellary District of Karnataka, India, and Revealed Activity Concentrations of 238U, 232Th, and 40K

Research has been conducted to examine the depth profile distribution of natural occurring radioactive elements, including 40K, 232Th, and 238U, in the soil of the Bellary District of Karnataka, India. Gamma-ray spectrometry techniques were employed to evaluate samples from five talukas in the Bellary districts employing 4˝x4˝ NaI (TI) Scintillation detectors. According to depth profiles and the distribution of naturally found radionuclides, the soil samples exhibit an amount of 238U at 91.81 Bq/kg, with the greatest concentration at 189.74 Bq/kg. But the concentration of 232Th also varies, ranging from 106.51 to 303.55 Bq/kg. Between 604.88 and 1080.29 Bq/kg, the range corresponds to a 40K activity concentration. In these areas, there has been no evident correlation between the quantities of 238U and 232Th in a soil surrounding the residences. 40K/232Th and 40K/238U proportion forecasts were also made using surface-level samples, which could not have included identical ratios as the ones being examined.

Nanoformulation of Polymyxin E Through Complex Coacervation: A Pharmacokinetic Analysis.

Objectives: Polymyxin E (PME), a polymyxin antibiotic, serves as a final resort against antibiotic resistance. Nephrotoxicity is the primary concern when employing PME. To alleviate this issue, researchers have explored strategies including dosing adjustments and innovative formulations. This study employed complex coacervation to create PME nanoformulations, capitalizing on PME's charge properties. The research question and hypothesis posed pertained to whether neutralization of PME's positive charge during formulation would reduce its antibiotic efficacy and alter its tissue distribution and other pharmacokinetic parameters. Our objective was to evaluate the capability of complex coacervation to mitigate the adverse effects of PME while preserving its antibacterial potency and therapeutic effectiveness. Methods: Three negatively charged polyions: potassium sucrose octasulfate, polytamic acid, and sodium hyaluronate, were used for formulation. We performed characterization on the nanocomplex formed by the polyions and PME. The nanoformulations underwent several tests, including minimum inhibitory concentration, in vivo efficacy on an infected mouse model, pharmacokinetic assessments, tissue distribution, and toxicity. Results: the three polyions formed coacervation complexes with PME at varying charge ratios, yielding nanoparticles smaller than 30 nm with low polydispersity (PDI < 0.3). The results demonstrated that complex coacervation-mediated PME nanoformulations exhibited equivalent or superior antibacterial activity, increased maximum tolerant dose, and fewer adverse reactions in animal tests. Conclusions: Utilizing complex coacervation, PME nanoformulations were developed, demonstrating efficacy in the formulation process. Pharmacokinetic assessments revealed absorption and distribution profiles akin to those of standalone PME. The positive charge inherent in PME causing its toxicity was mitigated after complex coacervation.

A Comparative Study of Two WAAM Patterns for Structures with Grid Fin Characteristics.

As a critical component of rocket systems, the grid fin is widely applied in the aerospace industry. Compared to traditional manufacturing methods and other additive manufacturing (AM) techniques, wire arc additive manufacturing (WAAM) is more advantageous in its time and cost efficiency, especially when it is utilized in the large-scale production of components. Given the significant effect of the welding strategies on the quality of manufactured parts, we investigated two distinct WAAM printing orientations, horizontal, or lie (L), and perpendicular, or stand (S), using a small-scale model. The feasibility of these two printing approaches was evaluated by analyzing the surface quality, microstructure, and mechanical properties at the junctions of the grid fin. Furthermore, a finite element analysis (FEA) was adopted to simulate and analyze the main factors, including the temperature distribution, deformation, and stress profiles at the welding joints, in both AM strategies. The integrated approach adopted in this study provides important insights for optimizing the application of WAAM in grid fin manufacturing. In summary, our results indicate that while the L mode is easily manufacturable and exhibits stable properties, the S mode holds significant market potential if its welding parameters are optimized.

Sex-Specific Analysis of the Relationship Between Ventricular Premature Contractions Frequency Distribution and Heart Rate: A Cross-Sectional Study in Chinese Adults.

To investigate the correlation between premature ventricular contraction (PVC) frequency and heart rate (HR) in Chinese adults, with an emphasis on sex-specific differences in clinical characteristics. This retrospective study analyzed 24-hour Holter monitoring data from 478 inpatients at the First People's Hospital of Yibin between January 2021 and December 2022. The inclusion criteria were age ≥18 years, ≥20hours of Holter recording, frequent PVCs (≥ 500 PVCs), and complete clinical profiles. Patients were stratified into three groups on the basis of the hourly correlation between PVC counts and HR: fast heart rate-related PVC (F-HR-PVC), slow heart rate-related PVC (S-HR-PVC), and independent heart rate-related PVC (I-HR-PVC). Heart rate variability (HRV) indices were assessed to evaluate autonomic nervous system activity. Among the 478 patients, 267 were males and 211 were females with a mean age of 65.7±13.0 years. The mean PVC burden was 5.7±7.0%, and the mean left ventricular ejection fraction (LVEF) was 59.1±8.7%. In males, the F-HR-PVC group was most common (45.3%), while in females, the I-HR-PVC group was most prevalent (50.2%). Despite these observed differences, a chi-square test did not reveal statistically significant differences in the distribution of VPC profiles between sexes (P=0.167). Analysis of clinical characteristics and Holter indices across sex groups showed significant differences in males, particularly in age, maximum heart rate, and minimum heart rate (P < 0.05). In females, significant intergroup differences were observed in VPC burden (P < 0.05). Although no significant sex differences were observed in the correlation between PVC frequency and HR, the study suggests a potential gender influence on VPC characteristics. These findings may inform future research and have implications for the development of sex-specific diagnostic and therapeutic strategies for PVCs.

In-human Nanofluidic Air Transport through Respirators and Masks

During the COVID-19 pandemic, the mandatory use of multiple surgical masks or N95 respirators in public raised concerns about potential health issues associated with the increased breathing force needed to maintain the breathing cycle. To address these concerns, we conducted a comprehensive study investigating the transportation and filtering mechanisms of heterogeneous nanoparticles and virus-like particles through surgical masks and N95 respirators. Our multifaceted approach combined in vitro experiments utilising aerosol spray paints containing nanoparticles and in vivo validation on human volunteer inhaling city air. We employed scanning electron microscopy and transmission electron microscopy to analyse the distribution of nanoparticles across various mask layers and pristine silicon substrates placed on human skin. In addition, we provide analytical insights into the pressure distribution and fluid velocity profiles within the complex polymer fibre network of the masks. Our findings remarkably revealed that both single surgical masks and N95 respirators exhibited similar nanofluidic performance in filtering colloidal and jet-stream nanoparticles in the air. These results have significant implications for policymakers in developing regulations to manage airborne pandemics and air pollution control, ultimately enhancing public health and safety during respiratory health crises.

Statistical analysis and numerical simulation of wire coating process with sisko nanofluid: exploring variable thermophysical properties

The wire coating process enhances wire durability, safety, and performance, preventing corrosion and providing insulation against abrasion, temperature changes, and chemicals. To evaluate process quality, characteristics like fluid flow and heat transfer in the die are analysed. This work focuses on understanding molten polymer rheology via momentum, thermal distribution, and nanoparticle volume fraction profiles. A mathematical model is developed for a Sisko fluid using the Buongiorno model, which includes temperature-dependent thermophysical properties. The governing equation is reduced to dimensionless form using non-dimensional parameters and solved using the numerical technique. The results are visualised graphically for the parameters like Sisko fluid parameter, viscosity parameter (between 0 and 1), Brinkmann number, Hartmann number (between 2 and 10) using 2D and 3D plots. The study shows that the thermal field is enhanced by nanofluid factors, which subsequently enhances the heat transfer rate in the presence of nanoparticles. The optimization of the responses: shear stress rate ( S rz ) and rate of heat transfer ( Nur ) is carried out concurrently using the Surface Response Method. Furthermore, a sensitivity analysis has been conducted. The findings indicate that the viscosity parameter significantly impacts the sensitivity of the both shear stress rate and heat transfer rate.

Radiative convective heat transfer and magneto-hydrodynamic flow in a viscous fluid-saturated porous channel with variable thermal conductivity

The proposed model offers a wide range of practical use, including nuclear energy plants, oil recovery, geothermal extraction, solar systems, dispersing fog, electrical power generation, hydro-metallurgical industry and advancements in medical sciences. The article explores the impact of radiative-convective heat transfer(HT) and magneto-hydrodynamic flow of a viscous fluid in a vertical porous channel with varying thermal conductivity and viscosity. The developing mathematical model analyses fluid flow and temperature distribution profiles. The nonlinear coupled differential equations (DEs) have been solved analytically and numerically. The numerical solution has been obtained from the Chebyshev spectral collocation method and a significant agreement is found with the analytical solution in the special case. The obtained solution offers a graphical representation of velocity, and temperature profiles have been found with respect to involving various parameters. The authors also study the behaviour of fluid flow near the surface and heat transfer from high to low temperatures at the walls. Correlations have been established for skin friction and Nusselt number in relation to involving parameters. The study reveals that the velocity profile is more pronounced when thermal conductivity changes compared to variable viscosity. The purpose of the study is to enhance the efficiency of oil recovery, geothermal extraction, etc., models.

Comprehensive Analysis of β-1,3-Glucanase Genes in Wolfberry and Their Implications in Pollen Development.

β-1,3-Glucanases (Glu) are key enzymes involved in plant defense and physiological processes through the hydrolysis of β-1,3-glucans. This study provides a comprehensive analysis of the β-1,3-glucanase gene family in wolfberry (Lycium barbarum), including their chromosomal distribution, evolutionary relationships, and expression profiles. A total of 58 Glu genes were identified, distributed across all 12 chromosomes. Evolutionary analysis revealed six distinct branches within wolfberry and nine distinct branches when compared with Arabidopsis thaliana. Expression analysis showed that 45 Glu genes were expressed in berries, with specific genes also being expressed in flowers and leaves. Notably, LbaGlu28 exhibited significant expression during the tetrad stage of pollen development and was localized in the cell wall. These findings provide valuable insights into the functional significance of Glu genes in wolfberry, highlighting their roles in development and their potential involvement in reproductive processes, particularly in pollen development.

Integrated approach to determining the effectiveness of the reservoir pressure maintenance system in carbonate reservoirs

Relevance. The need to improve the oil recovery factor from carbonate reservoirs by increasing sweep/displacement coefficients, as well as by searching for ways to improve the efficiency of the reservoir pressure maintenance system. Aim. To increase the efficiency of developing carbonate reservoirs using a reservoir pressure maintenance system through an integrated approach to studying the impact of injected fluid on reservoir systems with natural and man-made fracturing. Objects. Bashkir (C2bsh) and Vereisky (C2vr) Middle Carboniferous objects of the Dachnoe structure of the Dachnoe deposit of the Republic of Tatarstan, tectonically confined to the Ulyanovsk structure of the South Tatar arch. Methods. Seismic, acoustic, radioactive, hydrodynamic methods, as well as methods of ground microseismic monitoring to identify the nature of the activation of natural and man-made fracturing during hydraulic fracturing and cyclic injection into injection wells. Results. The authors have carried out an analysis of the hydrodynamic system of carbonate reservoirs of the Vereiskian-Bashkirian deposits; identified filtration channels; assessed the direction of injected fluid movement; carried out the analysis of the impact of the formation pressure maintenance system on producing wells at various injection modes and compensation levels in carbonate reservoirs. When carrying out hydraulic fracturing in the reservoirs under consideration, it was established that the crack propagates to both objects, thereby forming a single hydrodynamic system. The conclusions obtained from the work indicate the effectiveness of the system for maintaining reservoir pressure in these carbonate reservoirs. Clarification of data on the filtration channels of both the working agent and the oil displaced by it, in combination with knowledge of the rates of movement of the injected liquid and its distribution profiles, makes it possible to effectively manage the oil field development.

Antifungal susceptibility profile of Candida species and uncommon yeasts from drug abusers with oral candidiasis

In Iran, there is limited information regarding the species distribution and antifungal susceptibility profiles of yeast isolates from drug addicts suffering from oral candidiasis (OC). In this study, 104 yeast isolates, including 98 Candida species and 6 uncommon yeasts, were collected from 71 drug abusers with OC. The susceptibility profiles of Candida spp. and uncommon yeasts to amphotericin B (AMB), itraconazole (ITC), nystatin (NYC), fluconazole (FLC), and caspofungin (CAS) were evaluated using the CLSI broth microdilution method. The prevalence of OC in the sampled population was found to be 29%. The susceptibility profile of Candida spp. revealed remarkable sensitivity, with 100% and 99% of isolates susceptible to NYC and AMB, respectively. However, concerning levels of resistance or non-wild-type minimum inhibitory concentrations (MICs) were observed, with 13.2% of Candida isolates showing resistance to FLC, 13.2% to ITC, and 16.3% to CAS. Notably, 35.2% of patients showed mixed yeast species, while 5.1% of Candida isolates exhibited multidrug resistance. The analysis of the uncommon yeast species showed that the overall frequencies of the highest MICs were observed for CAS. Furthermore, within the six non-Candida species identified, Hanseniaspora opuntiae and one isolate of Pichia kluyveri exhibited resistance to FLC and ITC, respectively, while all non-Candida species were susceptible to AMB and NYC. Additionally, one isolate of Pichia kluyveri exhibited simultaneously high MICs to two drugs ITC and CAS. Furthermore, the Hanseniaspora opuntiae isolate showed high MICs to CAS and FLC. The findings from the present study suggest that AMB and NYC can be suitable choices for empiric treatment of both common Candida species and uncommon yeast infections in substance abuse patients.

Influence of substrate material and coating thickness on biomechanical stress distribution

This study investigates the influence of TiO₂ coating thickness on the mechanical performance of metallic substrates 316L stainless steel and Ti6Al4V, commonly used in biomedical applications. A finite element analysis (FEA) was conducted to evaluate stress and pressure distributions under varying coating thicknesses during simulated mechanical loading. The analysis aimed to optimize coating parameters to enhance stress resistance and load distribution while minimizing potential substrate failure. Results revealed that increasing TiO₂ coating thickness significantly alters the stress profile and pressure distribution, with specific thicknesses providing optimal load-bearing capabilities. Ti6Al4V demonstrated superior mechanical performance compared to 316L under identical conditions, attributed to its higher strength-to-weight ratio. The findings highlight the critical role of coating thickness and substrate material selection in improving mechanical reliability and longevity of biomedical implants. This study provides valuable insights for designing durable and efficient coated metallic biomaterials, paving the way for advanced applications in the medical field.